CATALYST ARTICLES AND EXHAUST GAS TREATMENT SYSTEMS

Abstract

To provide a diesel engine exhaust gas treatment system that prevents sulfation without increasing catalyst costs and has sufficient NOx purification capacity and HC poisoning resistance. [Solution] The solution is provided by a system comprising, from the upstream of the exhaust gas flow, (i) a first catalyst 2 containing palladium supported on zirconia and one or more of a zeolite material containing vanadium oxide or a metal, and (ii) a second catalyst 3 containing a platinum-group supported catalyst and one or more of a zeolite material containing vanadium oxide, tungsten oxide or a metal.

Description

[Technical Field]

[0001] The present invention relates generally to the field of selective catalytic reduction and oxidation catalysts. In particular, the present invention relates to catalytic articles for treating exhaust gas streams leaving diesel engines, exhaust gas treatment systems, and catalysts for selective catalytic reduction of NOx and oxidation of hydrocarbons. Additionally, the present invention relates to methods for making said articles, catalysts, and systems. [Background technology]

[0002] Nitrogen oxides (NO x ) harmful components cause air pollution. x NO is found in exhaust gases from internal combustion engines (e.g., in cars and trucks), combustion facilities (e.g., power plants fired by natural gas, oil, and coal), and nitric acid production plants. x Various treatment methods are used to reduce the amount of nitrogen oxides, thereby reducing atmospheric pollutants. One type of treatment involves catalytic reduction of nitrogen oxides. There are two types: (1) non-selective reduction methods, in which carbon monoxide, hydrogen, or lower hydrocarbons are used as reducing agents; and (2) selective reduction methods, in which ammonia or an ammonia precursor is used as a reducing agent. Selective reduction methods can achieve high levels of nitrogen oxide removal using small amounts of reducing agent.

[0003] Selective reduction processes are called SCR (selective catalytic reduction) processes, which use the catalytic reduction of nitrogen oxides with a reducing agent (e.g., ammonia or an ammonia precursor) in the presence of atmospheric oxygen, forming primarily nitrogen and steam.

[0004] 4NO+4NH3+O2→4N 2+ 6H2O (standard SCR reaction) 2NO2 + 4NH3 → 3N2 + 6H2O (slow SCR reaction) NO + NO2 + 2NH3 → 2N2 + 3H2O (fast SCR reaction)

[0005] This method is considered one of the most feasible techniques for removing nitrogen oxides from engine exhaust gases. In typical exhaust gases, nitrogen oxides consist primarily of NO (>90%), which is converted to nitrogen and water by an SCR catalyst in the presence of ammonia (standard SCR reaction). While urea can also be used as an ammonia precursor, NH3 is one of the most effective reducing agents. Generally, catalysts used in SCR processes should have good catalytic activity over a wide range of temperatures, e.g., from below 200°C to above 600°C. Higher temperatures are typically encountered during soot filter regeneration and SCR catalyst regeneration. In the context of soot filters, regeneration refers to the periodic need to remove soot accumulated within the filter. To effectively combust the soot, temperatures above 500°C are typically required for 20 minutes or more. Such temperatures are not encountered during normal engine operation.

[0006] Hydrocarbons, typically present in the exhaust as fuel or partially combusted fuel, are oxidized through a dedicated oxidation catalyst to generate the heat necessary to oxidize the soot collected in the filter. Depending on the location of the SCR catalyst relative to the filter, for example, if the SCR catalyst is located between a hydrocarbon source, such as the engine, and a DOC equipped to oxidize these hydrocarbons for heat generation, the SCR catalyst may be exposed to high hydrocarbon concentrations. Placing the SCR very close to the engine is intended to take advantage of more rapid heating during cold starts. The term "close-coupled" is often used and is defined below. Regeneration does not have the same meaning for SCR catalysts as it does for filters. In this case, trace components of the exhaust gas collect or interact with the SCR catalyst, reducing its effectiveness over time. Periodic removal of these pollutants is necessary to maintain high efficiency. For example, sulfur oxides react with ammonia to form ammonium sulfate, which can block active sites on the catalyst surface, resulting in loss of activity. Similarly, prolonged operation of SCR catalysts at temperatures below about 300° C. can lead to the accumulation of HCs on the catalyst surface. Ultimately, these hydrocarbons also block active sites, resulting in a loss of catalytic activity.

[0007] As with filters, higher temperatures are periodically required to remove these and other pollutants and maintain high catalyst efficiency. Achieving the temperature to regenerate the SCR catalyst requires hydrocarbon addition in combination with an oxidation catalyst to increase the exhaust temperature. The addition of an oxidation function to the SCR can also oxidize ammonia (which is added as part of the SCR reaction). This results in reduced SCR catalyst activity and, in some cases, NOx. x NO than lowering emissions x Emissions could potentially increase. Therefore, catalysts have been developed specifically to oxidize ammonia.

[0008] DE 10 2015 015 260 (A1) discloses an exhaust gas treatment system for an internal combustion engine, which comprises a first SCR catalyst containing vanadium oxide, a particulate filter located downstream of the first SCR catalyst, a second SCR catalyst, i.e., Cu-SCR, located downstream of the particulate filter, and an ammonia slip catalyst located downstream of the second catalyst. The first SCR catalyst has an effect comparable to that of a DOC for ensuring passive regeneration of the downstream particulate filter.

[0009] DE 102015016986 (A1) discloses an exhaust gas treatment system for an internal combustion engine comprising at least one first catalytic converter through which exhaust gases originating from the internal combustion engine can flow and at least one particulate filter immediately downstream of the catalytic converter, wherein the first catalytic converter comprises a first section which is a selective catalytic reduction (SCR) catalyst (V-SCR), a second section downstream of the first section which is an ammonia slip catalyst, and a third section downstream of the second section which is an oxidation catalyst, and SCR catalyst layers arranged in the second and third sections.

[0010] WO2015 / 130216(A1) discloses an exhaust gas treatment system comprising an oxidation catalyst, a first dosing device arranged downstream of the oxidation, a first reduction catalyst device arranged downstream of the dosing device, and a particulate filter arranged downstream of the first reduction catalyst. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] DE102015015260(A1) [Patent Document 2] DE102015016986(A1) [Patent Document 3] WO2015 / 130216(A1) Summary of the Invention [Problem to be solved by the invention]

[0012] It is a known problem that close-coupled selective catalytic reduction (SCR) catalysts based on copper-containing zeolite materials with a CHA-type framework structure can become sulfated over time due to sulfur trioxide emitted from the engine and generated internally by the SCR catalyst, even in the absence of an upstream oxidation catalyst. The term "close-coupled" catalyst is used herein to define a catalyst that is the first catalyst to receive the exhaust gas stream from the engine (this catalyst is located in close proximity (directly next to) the engine with no other catalytic components in between). Therefore, close-coupled SCR catalysts cannot achieve sufficient de-NOx to meet ultra-trace nitrogen oxide (NOx) and nitrous oxide (NO) emissions, such as CARB, after sulfation. [Means for solving the problem]

[0013] It was therefore an object of the present invention to provide an exhaust gas treatment system and catalyst article for treating an exhaust gas stream exiting a diesel engine that is cost effective and resistant to HC poisoning and prevents sulfation to maintain sufficient de-NOx to meet environmental requirements while avoiding engine measures such as increased exhaust gas temperatures. DETAILED DESCRIPTION OF THE INVENTION

[0014] I. Catalyst article Surprisingly, it has been found that catalyst articles according to the present invention are cost-effective and resistant to HC poisoning and sulfation to maintain sufficient de-NOx to meet environmental requirements while avoiding engine measures such as increased exhaust gas temperatures.

[0015] Thus, the present invention is directed to a catalyst article comprising a catalyst composition designed to oxidize hydrocarbons (HC) without oxidizing ammonia, and also to achieve activity for the NH3-SCR reaction. The catalyst composition includes at least two distinct components: a NOx reduction component, such as an SCR catalyst, and an oxidation catalyst component, such as a platinum group metal, impregnated on a porous support material. This dual-function catalyst composition is most useful in engine exhaust gas treatment systems that use hydrocarbons during the regeneration process of selective catalytic reduction (SCR) catalysts and soot filters. Hydrocarbons, such as fuel, can either be provided in the exhaust by engine management protocols or injected into the exhaust gas stream entering the catalyst article to increase the temperature of the SCR catalyst to remove pollutants from the SCR catalyst surface. The heat generated in the SCR catalyst by this dual-function catalyst can also be useful in removing accumulated soot from downstream filters. The hydrocarbon oxidation function does not involve ammonia oxidation, and therefore the SCR catalyst can reduce NOx by oxidizing ammonia. x Reduction can continue while simultaneously generating heat for regeneration. In certain embodiments, the flexibility of eliminating the upstream oxidation catalyst typically required to generate heat to clean the SCR catalyst or soot filter reduces the thermal mass between the engine and the SCR catalyst. Reducing the thermal mass reduces the time required to heat the SCR catalyst to operating temperature. Shorter heat-up times result in faster, lower emissions during cold operating cycles.

[0016] In applications where the SCR catalyst is located downstream from the filter, the oxidation activity built into the SCR catalyst facilitates the reduction of any unreacted hydrocarbons from the filter during regeneration without affecting the performance of the SCR catalyst. Thus, the dual activity of the disclosed catalyst composition not only provides for the oxidation of HCs, but also, within the appropriate temperature window, for example, NO xThe catalytic articles of the present invention do not interfere with SCR catalyst activity by causing oxidation of the ammonia and / or ammonia precursors required for conversion, thereby enabling an efficient hydrocarbon regeneration cycle in engine exhaust gas treatment systems to restore SCR catalyst activity.

[0017] The present invention provides a catalyst article comprising a substrate having a catalyst composition disposed thereon, the catalyst composition comprising a platinum group metal (PGM) impregnated on a porous support surface, and a selective catalytic reduction (SCR) catalyst, wherein the catalyst composition is substantially free of platinum (Pt), and the catalyst article is configured to reduce nitrogen oxides (NO x The present invention provides a catalyst article that is effective in reducing CO₂ and hydrocarbons (HC).

[0018] Preferably, the PGM is palladium (Pd), rhodium (Rh), or a combination thereof. More preferably, the PGM is palladium or rhodium. An exemplary PGM loading, calculated as PGM element, is about 5 g / ft 3 ~about 25g / ft 3 The PGM is impregnated into a porous support, preferably a refractory metal oxide material, for example, ceria, zirconia, yttria, lanthana, neodymia, praseodymia, or a combination thereof.

[0019] Preferably, the metal oxide is a ceria-zirconia composite. More preferably, the ceria and zirconia of the ceria-zirconia composite are each present in an amount ranging from about 5 to about 75% by weight (e.g., about 25 to about 60% by weight), based on the total weight of the ceria-zirconia oxide composite. Ceria is typically present in the ceria-zirconia composite in an amount ranging from about 30 to about 45% by weight, based on the total weight of the ceria-zirconia composite. Zirconia is typically present in an amount ranging from about 35 to about 55% by weight, based on the total weight of the ceria-zirconia composite. Alternatively, the refractory metal oxide material is preferably alumina.

[0020] The SCR catalyst may comprise a mixed metal oxide component or a metal ion-exchanged molecular sieve. Preferably, the mixed metal oxide component is FeTiO3, FeAl2O3, MgTiO3, MgAlO3, MnO x The metal is selected from the group consisting of TiO2, CuTiO3, CeZrO2, TiZrO2, V2O5 / TiO2, and mixtures thereof. For example, the mixed metal oxide component can be titania and vanadia (and optionally tungsten), such that the vanadia is present in the mixed metal oxide component in an amount ranging from about 1% to about 10% by weight, based on the total weight of the mixed metal oxide. When the SCR catalyst is a metal ion-exchanged molecular sieve, the metal can be selected from Cu, Co, Ni, La, Mn, Fe, V, Ag, Ce, Nd, Mo, Hf, Y, W, and combinations thereof. Preferably, the metal is Cu, Fe, or a combination thereof. The metal, calculated as the metal oxide, is typically present in an amount ranging from about 0.1% to about 10% by weight, based on the weight of the ion-exchanged molecular sieve. More preferably, the metal is Cu.

[0021] Certain zeolites are particularly advantageous for use as molecular sieves. For example, the zeolite may have a structure type selected from AEI, AFT, AFV, AFX, AVL, CHA, DDR, EAB, EEI, ERI, IFY, IRN, KFI, LEV, LTA, LTN, MER, MWF, NPT, PAU, RHO, RTE, RTH, SAS, SAT, SAV, SFW, TSC, and UFI, and combinations thereof. In the context of the present invention, "zeolite" may refer to a "zeolitic material" as defined in paragraphs II and III below. In the context of the present invention, the terms "structure type," "framework structure type," and "type of framework structure" are used interchangeably.

[0022] In the context of the present invention, it is preferred that the zeolite contained in the catalyst composition, more preferably having structural type CHA, has an average crystal size, as determined by scanning electron microscopy, of at least 0.5 micrometers, preferably in the range of 0.5 to 1.5 micrometers, more preferably in the range of 0.6 to 1.0 micrometers, more preferably in the range of 0.6 to 0.8 micrometers.

[0023] The substrate is typically a honeycomb substrate, which may be made of metal or ceramic. Exemplary honeycomb substrates are either flow-through substrates or wall-flow filters.

[0024] The catalyst composition can include multiple layers, such as a first layer and a second layer, where the first layer includes the SCR catalyst and the second layer includes the PGM impregnated on a porous support. The order of the layers can vary, including the first layer being disposed directly on the substrate and the second layer being disposed on top of the first layer, and the second layer being disposed directly on the substrate and the first layer being disposed on top of the second layer.

[0025] Alternatively, the catalyst composition can include a single layer. Preferably, the catalyst composition consists of a single layer. For example, the catalyst article of the present invention can be a first catalyst according to (i) in an exhaust gas treatment system defined in paragraph II, or a second catalyst according to (ii) in an exhaust gas treatment system defined in paragraph III.

[0026] As a further alternative, the first and second layers may be disposed directly on the substrate in a zoned configuration. In this regard, the substrate of the catalyst article preferably comprises a plurality of passages defined by the interior walls of the substrate having an inlet end, an outlet end, and a substrate length spanning the inlet end to the outlet end of the substrate. Preferably, the catalyst composition comprises a first layer and a second layer, the first layer comprising a PGM impregnated on a porous support surface, and the second layer comprising an SCR catalyst.

[0027] More preferably, the first layer extends from the inlet end to the outlet end of the substrate over 5 to 95% of the substrate length, and the second layer extends from the outlet end to the inlet end over 5 to 95% of the substrate length. More preferably, the first layer extends from the inlet end to the outlet end of the substrate over 20 to 80%, more preferably 30 to 70%, more preferably 40 to 60%, more preferably 45 to 55% of the substrate length, and the second layer extends from the outlet end to the inlet end over 20 to 80%, more preferably 30 to 70%, more preferably 40 to 60%, more preferably 45 to 55% of the substrate length.

[0028] According to said alternative, the first layer preferably comprises palladium impregnated in one or more of zirconia and alumina.

[0029] Preferably, the first layer has a palladium content of 5 to 100 g / f, calculated as elemental palladium. 3 in the range of 0.71 to 2.82 g / l (20 to 80 g / ft 3 ), more preferably in the range of 1.06 to 2.47 g / l (30 to 70 g / ft 3 ), more preferably in the range of 1.24 to 1.94 g / l (35 to 55 g / ft 3 ), more preferably in the range of 1.41 to 1.77 g / l (40 to 50 g / ft 3 ) containing palladium in a loading range.

[0030] It is preferable that 98 to 100 mass %, preferably 99 to 100 mass %, and more preferably 99.5 to 100 mass % of the first layer is made of palladium impregnated into one or more of zirconia and alumina.

[0031] Preferably, the SCR catalyst of the second layer comprises a Cu-containing zeolite, more preferably a zeolite having structure type CHA.

[0032] Preferably, the second layer further comprises a metal oxide bond material, preferably a metal oxide bond material as defined in paragraphs II and III below.

[0033] Preferably, 98 to 100% by weight, more preferably 99 to 100% by weight, more preferably 99.5 to 100% by weight of the second layer consists of a Cu-containing zeolite, preferably a zeolite having structure type CHA, and a metal oxide binder as defined in paragraphs II and III below.

[0034] Furthermore, the present invention provides a method for reducing nitrogen oxides (NO ) in an exhaust gas stream by contacting the gas with a catalytic article according to the present invention. x The present invention relates to a method for treating an exhaust gas stream, comprising the steps of: (a) reducing hydrocarbons (HC); and (b) reducing hydrocarbons (HC).

[0035] The present invention relates to an emissions treatment system for treating an exhaust gas stream, the system comprising: an engine (e.g., a diesel engine or other lean-burn engine) that generates the exhaust gas stream; a system in fluid communication with the exhaust gas stream; and a system for treating NO in the exhaust stream. x The present invention further relates to an emissions treatment system comprising a catalytic article according to the present invention located downstream from an engine, the catalytic article being adapted to reduce H and oxidize HC to form a treated exhaust gas stream, the catalytic article being positioned to preferably directly receive the engine exhaust gas stream produced by the engine without an intervening catalytic article; and an injector adapted to add a reducing agent (e.g., ammonia or an ammonia precursor) to the exhaust gas stream upstream of the catalytic article. The system may further include an injector located upstream of the catalytic article, the injector adapted to add hydrocarbons to the exhaust gas stream. Other catalytic articles, such as a diesel oxidation catalyst located downstream of the catalytic article, and / or a soot filter located downstream of the diesel oxidation catalyst, may be included.

[0036] When used in the context of paragraph I, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise.

[0037] As used herein, the term "catalyst" or "catalyst composition" refers to a substance that promotes a reaction. As used herein, the terms "upstream" and "downstream" refer to relative directions relative to the flow of the engine's exhaust gas stream from the engine to the exhaust pipe, with the engine being in the upstream position and the exhaust pipe and any pollutant reduction articles, such as filters and catalysts, being downstream from the engine.

[0038] As used herein, the term "stream" refers broadly to any combination of flowing gases that may contain solid or liquid particulate matter. The term "gas stream" or "exhaust gas stream" refers to a stream of gaseous constituents, such as the exhaust of a combustion engine, which may contain entrained non-gaseous components, such as liquid droplets, solid particulates, etc. The exhaust gas stream of a combustion engine typically contains products of combustion (CO and HO), products of incomplete combustion (carbon monoxide (CO) and hydrocarbons (HC)), oxides of nitrogen (NO), and the like. x ), combustible and / or carbonaceous particulate matter (soot), and unreacted oxygen and nitrogen.

[0039] As used herein, the term "substrate" preferably refers to a monolithic material onto which the catalyst composition is placed. As used herein, the term "support" preferably refers to any high surface area material, typically a metal oxide material, onto which the precious metal catalyst is applied.

[0040] As used in the context of paragraph I, the term "washcoat" has its ordinary meaning in the field of a thin, adherent coating of catalytic or other material applied to a substrate material, such as a honeycomb-type support member, that is sufficiently porous to permit the passage of the gas stream to be treated. Washcoats are formed by preparing a slurry containing particles of some solids content (e.g., 30% to 90% by weight) in a liquid vehicle, which is then coated onto the substrate and dried to obtain a washcoat layer.

[0041] As used herein, the term "catalyst article" refers to an element used to promote a desired reaction. For example, a catalyst article may include a washcoat containing a catalyst composition on a substrate. As used herein, "impregnated" or "impregnation" refers to the infiltration of a catalyst material into the porous structure of a support material. The term "reduction" refers to a decrease in amount caused by any means.

[0042] The present invention provides a method for producing nitrogen oxides (NO ) comprising a substrate having a catalyst composition disposed thereon. x The present invention is directed to a catalyst article effective for the reduction of NO and hydrocarbons (HC), wherein the catalyst composition comprises a platinum group metal (PGM) and a selective catalytic reduction (SCR) catalyst impregnated on a porous support, and is substantially free of platinum (Pt). Such catalyst articles are particularly useful in engine exhaust gas treatment systems where the regeneration methods for the selective catalytic reduction (SCR) catalyst and diesel particulate filter use hydrocarbons to increase exhaust temperatures. Hydrocarbons, such as fuel, are either pumped directly into the exhaust gas stream from the engine (e.g., as determined by the engine management system) or injected into the exhaust gas stream entering the catalyst article during a regeneration cycle to promote removal of pollutants at elevated temperatures from the SCR catalyst or downstream soot filter. In engine treatment systems including the catalyst articles of the present invention, the PGM component impregnated on the porous support is used to remove NO and hydrocarbons. x HCs can be oxidized without affecting the catalytic activity of the SCR catalyst for conversion. Thus, the HC oxidation catalyst component of the catalyst article will not cause significant oxidation of ammonia and / or ammonia precursors. As a result, an efficient regeneration cycle can be achieved, in which removal of pollutants from the catalyst using hydrocarbons can occur without adversely affecting SCR performance activity.

[0043] catalyst composition The catalyst composition of the present invention includes a platinum group metal (PGM) component impregnated on a porous support and an oxidation catalyst component, including a selective catalytic reduction (SCR) catalyst. As used in the context of paragraph I, "platinum group metal component" or "PGM component" refers to a platinum group metal or its oxide, such as palladium (Pd), ruthenium (Ru), rhodium (Rh), osmium (Os), iridium (Ir), and mixtures thereof. The PGM component does not include platinum (Pt). Preferably, the platinum group metal component is rhodium (Rh), palladium (Pd), or a combination thereof. More preferably, the platinum group metal component includes a combination of palladium (Pd) and rhodium (Rh), such as in a mass ratio of about 1:10 to about 10:1. Alternatively, more preferably, the platinum group metal is palladium or rhodium.

[0044] Preferably, the PGM components are impregnated into a porous support material, preferably a refractory metal oxide material. The concentration of the PGM components (e.g., Pd, Rh, or a combination thereof) can vary, but will typically be from about 0.1% to about 10% by weight, based on the weight of the impregnated support material. The catalyst composition is substantially free of platinum. As used herein, the term "substantially free of platinum" means that there is no additional platinum intentionally added to the catalyst composition, and preferably, any additional platinum is less than 0.01% by weight, based on the weight of the catalyst composition. Preferably, "substantially free of Pt" includes "free of Pt."

[0045] As used in the context of paragraph I, "refractory metal oxide material" refers to a metal-containing oxide material that exhibits chemical and physical stability at elevated temperatures, such as those associated with gasoline and diesel engine exhaust. Exemplary refractory metal oxide materials include alumina, silica, zirconia, titania, ceria, and physical or chemical mixtures thereof, including atomically doped combinations.

[0046] Preferably, the refractory metal oxide material is alumina.

[0047] Preferably, the "refractory metal oxide material" is modified with metal oxides of alkali, semi-metals and / or transition metals, such as La, Mg, Ba, Sr, Zr, Ti, Si, Ce, Mn, Nd, Pr, Sm, Nb, W, Y, Nd, Mo, Fe or combinations thereof.

[0048] Preferably, the amount of alkali, semi-metallic and / or transition metal oxide used to modify the "refractory metal oxide material" can range from about 0.5% to about 50% by weight, based on the amount of the "refractory metal oxide material." Exemplary combinations of refractory metal oxide materials include alumina-zirconia, ceria-zirconia, alumina-ceria-zirconia, lanthana-alumina, lanthana-zirconia, lanthana-zirconia-alumina, baria-alumina, baria lanthana-alumina, baria lanthana-neodymia-alumina, and alumina-ceria.

[0049] According to the present invention, in the catalyst article, the platinum group metal impregnated on the porous support is preferably palladium impregnated on zirconia, and the SCR catalyst preferably comprises one or more of a mixed metal oxide and a zeolite containing one or more of Cu and Fe. More preferably, the SCR catalyst comprises a zeolite containing Cu, more preferably a zeolite having a structure type CHA.

[0050] When the catalyst composition has a first layer and a second layer, it may be preferred that the SCR catalyst of the first layer comprises one or more of a mixed metal oxide and a zeolite comprising one or more of Cu and Fe, more preferably a mixed metal oxide, more preferably V2O5 / TiO2. More preferably, the PGM impregnated on the porous support is palladium or rhodium impregnated on ceria-zirconia. More preferably, the SCR catalyst of the first layer comprises V2O5 / TiO2. Alternatively, the SCR catalyst of the first layer preferably comprises a zeolite comprising one or more of Cu and Fe.

[0051] Preferably, a high surface area refractory metal oxide material is used, such as an alumina support material, also known as "gamma alumina" or "activated alumina," and has a surface area of ​​60 m 2 / g, often up to about 200m 2 / g or more. Preferably, the BET specific surface area is 60 m 2 / g over 200m 2 / g. "BET specific surface area" has its usual meaning, referring to the Brunauer, Emmett, and Teller method for determining surface area by N2 adsorption. Preferably, the BET specific surface area is determined as described in Reference Example 6. Preferably, the BET specific surface area is in the range of about 100 to about 150 m 2 / g, more preferably 100 to 150m 2 / g range. Useful commercial aluminas include high surface area aluminas, such as high bulk density gamma-alumina, and low or medium bulk density large pore gamma-alumina.

[0052] Preferably, the porous support includes ceria, zirconia (ZrO2), titania (TiO2), yttria (Y2O3), neodymia (Nd2O3), lanthana (La2O3), praseodymia (Pr6O 11 ), or mixtures thereof. Combinations of metal oxides are often referred to as mixed metal oxide composites. For example, a "ceria-zirconia composite" refers to a composite containing ceria and zirconia without specifying the amount of either component. Suitable ceria-zirconia composites include, but are not limited to, composites having a ceria content in the range of about 5 to about 75 wt.%, preferably about 10 to about 60 wt.%, more preferably about 20 to about 50 wt.%, and more preferably about 30 to about 45 wt.% (e.g., a ceria content of at least about 5 wt.%, preferably at least about 10 wt.%, more preferably at least about 20 wt.%, more preferably at least about 30 wt.%, and more preferably at least about 40 wt.%, with an upper limit of about 75 wt.%), based on the total weight of the ceria-zirconia composite.

[0053] Preferably, the zirconia content of a suitable ceria-zirconia composite is in the range of about 5 to about 75 wt%, preferably about 15 to about 70 wt%, more preferably about 25 to about 60 wt%, more preferably about 35 to about 55 wt% (e.g., at least about 5 wt%, preferably at least about 15 wt%, more preferably at least about 25 wt% ceria, more preferably at least about 35 wt%, more preferably at least about 45 wt%, with an upper limit of about 75 wt%), based on the total weight of the ceria-zirconia composite.

[0054] Preferably, the SCR catalyst comprises a mixed metal oxide component or a metal-promoted molecular sieve. In the case of an SCR catalyst comprising a mixed metal oxide component, the term "mixed metal oxide component," as used herein, refers to an oxide containing cations of more than one chemical element or cations of a single element in several oxidation states. More preferably, the mixed metal oxide is selected from the group consisting of Fe / titania (e.g., FeTiO), Fe / alumina (e.g., FeAlO), Mg / titania (e.g., MgTiO), Mg / alumina (e.g., MgAlO), Mn / alumina, Mn / titania (e.g., MnO). x / TiO2) (e.g. MnO x / Al2O3), Cu / titania (e.g., CuTiO3), Ce / Zr (e.g., CeZrO2), Ti / Zr (e.g., TiZrO2), vanadia / titania (e.g., V2O5 / TiO2) and mixtures thereof. More preferably, the mixed metal oxide component comprises vanadia / titania.

[0055] More preferably, the amount of vanadia present in the mixed metal oxide component (e.g., vanadia / titania) is in the range of about 1 to about 10 weight percent, preferably about 2 to about 8 weight percent, more preferably about 3 to about 6 weight percent, based on the total weight of the mixed metal oxide component (up to about 10%, preferably about 9%, more preferably about 8%, more preferably about 7%, more preferably about 6%, more preferably about 5%, more preferably about 4%, more preferably about 3%, more preferably about 2%, more preferably about 1 weight percent, based on the total weight of the mixed metal oxide component, with 0% being the lower limit).

[0056] More preferably, the mixed metal oxide component can be activated or stabilized. For example, vanadia / titania oxide can be activated or stabilized with tungsten (e.g., WO) to yield VO / TiO / WO. More preferably, the amount of tungsten present in the mixed metal oxide component (e.g., VO / TiO / WO) is in the range of about 0.5 to about 10 wt.% based on the total weight of the mixed metal oxide component (about 10%, preferably about 9%, more preferably about 8%, more preferably about 7%, more preferably about 6%, more preferably about 5%, more preferably about 4%, more preferably about 3%, more preferably about 2%, more preferably about 1 wt.% or less based on the total weight of the mixed metal oxide component, with 0% being the lower limit). More preferably, vanadia is activated or stabilized with tungsten (e.g., WO). Tungsten can be dispersed at a concentration ranging from about 0.5 to about 10 wt. % based on the total weight of vanadia (about 10%, preferably about 9%, more preferably about 8%, more preferably about 7%, more preferably about 6%, more preferably about 5%, more preferably about 4%, more preferably about 3%, more preferably about 2%, more preferably about 1 wt. % or less based on the total weight of vanadia, with 0% being the lower limit). Examples of mixed metal oxides as SCR catalysts are disclosed in U.S. Patent Application Publication No. 2001 / 0049339 to Schafer-Sindelindger et al.

[0057] In the context of SCR catalysts containing metal-promoted molecular sieves, the term "molecular sieve" refers to framework materials such as zeolites and other framework materials (e.g., isomorphously substituted materials). Molecular sieves are materials based on an extensive three-dimensional network of oxygen ions generally containing tetrahedral sites and having a substantially uniform pore distribution, with an average pore size of 20 Å or less. The pore size is defined by the ring size. It is understood that by defining a molecular sieve by its framework type, it is intended to include any zeolite or isomorphous framework material, such as SAPO, ALPO, and MeAPO, Ge-silicates, all-silica, and similar materials having the same type of framework.

[0058] Molecular sieves, e.g., zeolites, are generally defined as aluminosilicates with an open three-dimensional framework structure consisting of corner-sharing TO4 tetrahedra, where T is Al or Si, or optionally P. Cations that balance the charge balance of the anionic framework are loosely bound to framework oxygens, and the remaining pore volume is filled with water molecules. Non-framework cations are generally exchangeable, and water molecules are removable.

[0059] As used herein, the term "zeolite" refers to a specific example of a molecular sieve containing silicon and aluminum atoms. Zeolites are crystalline materials with fairly uniform pore sizes ranging from about 3 to 10 angstroms in diameter, depending on the type of zeolite and the type and amount of cations contained in the zeolite lattice. The silica-to-alumina (SAR) molar ratio of zeolites and other molecular sieves can vary over a wide range but is generally greater than or equal to 2. Preferably, the molecular sieves have an SAR molar ratio ranging from about 2 to about 300, including from about 5 to about 250, from about 5 to about 200, from about 5 to about 100, and from about 5 to about 50. More preferably, the molecular sieves have an SAR molar ratio ranging from about 10 to about 200, from about 10 to about 100, from about 10 to about 75, from about 10 to about 60, and from about 10 to about 50. The molecular sieve may have an SAR molar ratio in the range of about 15 to about 100, about 15 to about 75, about 15 to about 60, and about 15 to about 50. The molecular sieve may have an SAR molar ratio in the range of about 20 to about 100, about 20 to about 75, about 20 to about 60, and about 20 to about 50.

[0060] Preferably, when referring to an aluminosilicate zeolite framework type, the material is limited to molecular sieves that do not contain phosphorus or other metals substituted in the framework. However, for clarity, "aluminosilicate zeolite," as used herein, excludes aluminophosphate materials such as SAPO, ALPO, and MeAPO materials, and the broader term "zeolite" is intended to include aluminosilicates and aluminophosphates. The term "aluminophosphate" refers to another specific example of a molecular sieve that contains aluminum and phosphate atoms. Aluminophosphates are crystalline materials with fairly uniform pore sizes.

[0061] Preferably, the molecular sieve comprises independently SiO4 / AlO4 tetrahedra connected by common oxygen atoms to form a three-dimensional network. Preferably, the molecular sieve comprises SiO4 / AlO4 / PO4 tetrahedra. Molecular sieves can be distinguished primarily according to the geometry of the voids formed by the rigid network of (SiO4) / AlO4 or SiO4 / AlO4 / PO4 tetrahedra. The void entrances are formed from 6, 8, 10, or 12 ring atoms relative to the atoms forming the entrance opening. Preferably, the molecular sieve comprises a ring size of 12 or less, including 6, 8, 10, and 12.

[0062] Preferably, the molecular sieve can be based on the topology of the framework to which the structure is specified, typically ABW, ACO, AEI, AEL, AEN, AET, AFG, AFI, AFN, AFO, AFR, AFS, AFT, AFX, AFY, AHT, ANA, APC, APD, AST, ASV, ATN, ATO, ATS, ATT, ATV, AVL, AWO, AWW, BCT, BEA, BEC, BIK, BOG, BPH, BRE, CAN, CAS, SCO, CFI, SGF, CGS, CHA, CHI, CLO, CON, C ZP, DAC, DDR, DFO, DFT, DOH, DON, EAB, EDI, EEI, EMT, EON, EPI, ERI, ESV, ETR, EUO, FAU, FER, FRA, GIS, GIU, GME, GON , GOO, HEU, IFR, IFY, IHW, IRN, ISV, ITE, ITH, ITW, IWR, IWW, JBW, KFI, LAU, LEV, LIO, LIT, LOS, LOV, LTA, LTL, LTN, MA R, MAZ, MEI, MEL, MEP, MER, MFI, MFS, MON, MOR, MOZ, MSO, MTF, MTN, MTT, MTW, MWF, MWW, NAB, NAT, NES, NON, NPO, NPT, NSI, OBW, OFF, OSI, OSO, OWE, PAR, PAU, PHI, PON, RHO, RON, RRO, RSN, RTE, RTH, RUT, RWR, RWY, SAO, SAS, SAT, SAV, SB Any zeolite framework type can be used, such as E, SBS, SBT, SFE, SFF, SFG, SFH, SFN, SFO, SFW, SGT, SOD, SOS, SSY, STF, STI, STT, TER, THO, TON, TSC, UEI, UFI, UOZ, USI, UTL, VET, VFI, VNI, VSV, WIE, WEN, YUG, ZON, or a combination thereof. Preferably, the molecular sieve comprises a framework structure type selected from AEI, AFT, AFV, AFX, AVL, CHA, DDR, EAB, EEI, ERI, IFY, IRN, KFI, LEV, LTA, LTN, MER, MWF, NPT, PAU, RHO, RTE, RTH, SAS, SAT, SAV, SFW, TSC, and UFI. More preferably, the molecular sieve comprises a framework structure type CHA.

[0063] Preferably, the molecular sieve comprises an 8-ring small pore aluminosilicate zeolite. As used herein, the term "small pore" refers to a pore opening smaller than about 5 angstroms, e.g., on the order of about 3.8 angstroms. The phrase "8-ring" zeolite refers to a zeolite having an 8-ring pore opening and double 6-ring secondary building units, with a cage-like structure resulting from the linking of the double 6-ring building units by four rings. Preferably, the molecular sieve is a small pore molecular sieve with a maximum ring size of 8 tetrahedral atoms.

[0064] As noted above, molecular sieves can include all of the aluminosilicate, borosilicate, gallosilicate, MeAPSO, and MeAPO compositions, including, but not limited to, SSZ-13, SSZ-62, natural chabazite, zeolites K-G, Linde D, Linde R, LZ-218, LZ-235, LZ-236, ZK-14, SAPO-34, SAPO-44, SAPO-47, ZYT-6, CuSAPO-34, CuSAPO-44, Ti-SAPO-34, and CuSAPO-47.

[0065] As referenced herein above, the disclosed SCR catalysts generally comprise metal-promoted molecular sieves (e.g., zeolites). As used herein, "promoted" refers to a molecular sieve that contains one or more intentionally added components, as opposed to containing impurities that may be naturally present in the molecular sieve. Thus, a promoter is a component that is intentionally added to enhance the activity of the catalyst compared to a catalyst that does not have the intentionally added promoter. To promote SCR of nitrogen oxides, a suitable metal may be exchanged into the molecular sieve. Copper is involved in the conversion of nitrogen oxides and therefore may be a particularly useful metal for exchange. Therefore, a catalyst composition comprising a copper-promoted molecular sieve, such as Cu-CHA, is preferably provided.

[0066] The metal promoter can generally be selected from the group consisting of alkali metals, alkaline earth metals, transition metals of Groups IIIB, IVB, VB, VIB, VIIB, VIIIB, IB, and IIB, Group IIIA elements, Group IVA elements, lanthanides, actinides, and combinations thereof. Additional metal promoters that can be preferably used to produce metal-promoted molecular sieves include, but are not limited to, cobalt (Co), nickel (Ni), lanthanum (La), manganese (Mn), iron (Fe), vanadium (V), silver (Ag), cerium (Ce), neodymium (Nd), praseodymium (Pr), titanium (Ti), chromium (Cr), zinc (Zn), tin (Sn), niobium (Nb), molybdenum (Mo), hafnium (Hf), yttrium (Y), tungsten (W), and combinations thereof. More preferably, the metal promoter is one or more of Cu and Fe. Combinations of such metals, such as copper and iron, can be used to provide a mixture of Cu-Fe promoted molecular sieves, such as Cu-Fe-CHA.

[0067] The metal promoter content of the metal-promoted molecular sieve, calculated as oxide, preferably ranges from about 0.1% to about 10%, preferably 0.1% to about 5%, more preferably from about 0.5% to about 4%, or more preferably from about 2% to about 5%, or more preferably from about 1% to about 3%, by weight, based on the total weight of the calcined molecular sieve (including promoter), reported on a volatile-free basis. Preferably, the metal promoter of the molecular sieve comprises Cu, Fe, or a combination thereof.

[0068] Base material The substrate for the catalyst article of the present invention can be constructed from any material typically used to manufacture automotive catalysts, and typically includes a metallic or ceramic honeycomb structure. The substrate typically provides multiple wall surfaces to which the washcoat composition of the catalyst article is applied and adhered, thereby acting as a support for the catalyst composition.

[0069] Exemplary metallic substrates include heat-resistant metals and metal alloys such as titanium and stainless steel, as well as other alloys in which iron is a substantial or major component. Such alloys can contain one or more of nickel, chromium, and / or aluminum, with the total amount of these metals advantageously comprising at least 15% by weight of the alloy, preferably 10-25% by weight chromium, 3-8% by weight aluminum, and up to 20% by weight nickel. The alloy may also contain small or trace amounts of one or more other metals, such as manganese, copper, vanadium, or titanium. The surface of the metal substrate can be oxidized at high temperatures, e.g., 1000°C or higher, to form an oxide layer on the surface of the substrate, improving the corrosion resistance of the alloy and promoting adhesion of a washcoat layer to the metal surface.

[0070] The ceramic material used to construct the substrate can include any suitable refractory material, such as cordierite, mullite, cordierite-alpha alumina, silicon nitride, zircon mullite, spodumene, alumina-silica magnesia, zircon silicate, sillimanite, magnesium silicate, zircon, petalite, alpha alumina, aluminosilicate, and the like.

[0071] Any suitable substrate may be used, such as a monolithic flow-through substrate, having a plurality of fine, parallel gas flow passages extending from the inlet face to the outlet face of the substrate, such that the passages are open for fluid flow. The passages, which provide a substantially direct path from the inlet to the outlet, are defined by walls coated with a catalytic material as a washcoat, such that gas flowing through the passages contacts the catalytic material. The flow passages in the monolithic substrate are thin-walled channels that can have any suitable cross-sectional shape, such as trapezoidal, rectangular, square, sinusoidal, hexagonal, elliptical, or tubular. Such structures can contain gas inlet openings (i.e., "cells") of about 60 to about 1200 or more cpsi per square inch of cross section (cpsi), more commonly about 300 to 600 cpsi. The wall thickness of the flow-through substrate can vary, with a typical range being between 0.002 and 0.1 inches. Typical commercially available flow-through substrates are cordierite substrates having 400 cpsi and a 6 mil wall thickness, or 600 cpsi and a 4 mil wall thickness, however, it will be understood that the present invention is not limited to any particular substrate type, material, or geometry.

[0072] Alternatively, the substrate may be a wall-flow substrate, in which each passage is plugged at one end of the substrate body with a nonporous plug, and alternate passages are plugged at the opposite end face. This requires that gas flow through the porous walls of the wall-flow substrate to reach the outlet. Such monolithic substrates can contain pressures of about 100 to 400 cpsi, more commonly up to about 700 cpsi or more, such as about 200 to about 300 cpsi. The cross-sectional shape of the cells can vary, as described above. Wall-flow substrates typically have wall thicknesses between 0.002 and 0.1 inches. Typical commercially available wall-flow substrates are constructed from porous cordierite, examples of which have a pressure of 200 cpsi and a 10-mil wall thickness, or 300 cpsi with an 8-mil wall thickness, and a wall porosity of between 45 and 65%. Other ceramic materials, such as aluminotitanate, silicon carbide, and silicon nitride, are also used as wall-flow filter substrates. However, it will be understood that the present invention is not limited to any particular substrate type, material, or geometry. It should be noted that when the substrate is a wall-flow substrate, the catalyst composition, in addition to being disposed on the surface of the wall, can also penetrate within the pore structure of the porous wall (i.e., partially or completely block the pore openings).

[0073] An exemplary substrate 2 in the form of a flow-through substrate coated with a washcoat composition described herein is illustrated in Figures 1 and 2. Referring to Figure 1, the exemplary substrate 2 has a cylindrical shape and a cylindrical outer surface 4, an upstream end face 6, and a corresponding downstream end face 8 identical to end face 6. The substrate 2 has a plurality of fine, parallel gas flow passages 10 formed therein. As can be seen in Figure 2, the gas flow passages 10 are defined by walls 12 and extend along the substrate 2 from the upstream end face 6 to the lower end face 8, and the passages 10 are unobstructed so that a fluid, e.g., a gas stream, flows longitudinally along the substrate 2 through the gas flow passages 10. As can be more easily seen in Figure 2, the walls 12 are sized and configured such that the gas flow passages 10 have a substantially symmetrical polygonal shape. As shown, the washcoat composition can be applied in multiple, separate layers, if desired. In this illustration, the washcoat consists of both a discrete bottom washcoat layer 14 adhered to the wall 12 of the substrate member, and a second discrete top washcoat layer 16 coated over the bottom washcoat layer 14. The invention can be practiced with one or multiple (e.g., two, three, or four) washcoat layers and is not limited to the illustrated two-layer embodiment. Alternatively, all catalyst compositions of the invention can be homogeneously mixed in the same catalyst layer, for example, as further defined above and in paragraphs II and III.

[0074] The catalyst article preferably comprises a catalyst composition having multiple layers, each layer having a different composition. The bottom layer (e.g., layer 14 in FIG. 2) can comprise the SCR catalyst composition of the present invention, and the top layer (e.g., layer 16 in FIG. 2) can comprise the oxidation catalyst component of the present invention (e.g., PGM component impregnated on a porous support). Alternatively, the catalyst article can comprise a catalyst composition in which the bottom layer (e.g., layer 14 in FIG. 2) can comprise the oxidation catalyst component of the present invention (e.g., PGM component impregnated on a porous support), and the top layer (e.g., layer 16 in FIG. 2) can comprise the SCR catalyst composition of the present invention.

[0075] The relative amounts of the SCR catalyst and oxidation catalyst components can vary. For example, the relative amounts of the PGM components in the oxidation catalyst component in an exemplary dual-layer coating each comprise about 10-90 wt. % of the total weight of the catalyst composition in the bottom layer (adjacent to the substrate), and the SCR catalyst is present in about 10-90 wt. % of the total weight of the catalyst composition in the top layer. The same percentages can apply when the SCR catalyst is present in the bottom layer and when the remaining components are present in the top layer.

[0076] FIG. 3 illustrates an exemplary substrate 2 in the form of a wall-flow filter substrate coated with a washcoat composition described herein. As can be seen in FIG. 3, the exemplary substrate 2 has a plurality of passages 52. The passages are tubularly surrounded by the interior wall 53 of the filter substrate. The substrate has an inlet end 54 and an outlet end 56. The passages are alternately blocked at the inlet end with an inlet plug 58 and at the outlet end with an outlet plug 60, forming opposing checkerboard patterns at the inlet 54 and outlet 56. Gas flow 62 enters an unblocked channel inlet 64, is blocked by an outlet plug 60, and disperses through the channel wall 53 (which is porous) to the outlet side 66. Gas cannot pass back to the inlet side of the wall due to the inlet plug 58. The porous wall-flow filters used in the present invention are catalyzed in that the walls of the element contain one or more catalyst materials thereon or therein. The catalytic material may be present solely on the inlet side of the element wall, solely on the outlet side, on both the inlet and outlet sides, or the wall itself may consist entirely or partially of catalytic material. The present invention includes the use of one or more layers of catalytic material on the inlet and / or outlet walls of the element. It may also be preferred for the substrate to be coated with at least two layers comprised of separate washcoat slurries in an axially segmented configuration. For example, the same substrate may be coated with one layer of washcoat slurry and another layer of washcoat slurry, each layer being different. This can be more easily understood with reference to FIG. 4, which shows an embodiment in which a first washcoat zone 24 and a second washcoat zone 26 are positioned side by side along the length of the substrate 22. The first washcoat zone 24 of a specific embodiment extends from the inlet end 25 of the substrate 22 across a range of about 5% to about 95% of the length of the substrate 22. The second washcoat region 26 extends from the outlet 27 of the substrate 22 from about 5% to about 95% of the total axial length of the substrate 22. The at least two component catalyst compositions in the treatment systems described in this invention can be zoned on the same substrate.Preferably, the oxidation catalyst component and the SCR catalyst are zoned on the same substrate. For example, referring back to FIG. 4, a first washcoat section 24 represents the oxidation catalyst component and extends from an inlet end 25 of the substrate across between about 5% and about 95% of the length of the substrate 22. A second washcoat section 26, including the SCR catalyst, is then positioned alongside section 24 and extends from an outlet 27 of the substrate 22. Alternatively, the first washcoat section 24 can represent the SCR catalyst, and the second washcoat section 26 can include the oxidation catalyst component. The oxidation catalyst component and the SCR catalyst may be zoned on different substrates as defined above and in paragraph III.

[0077] When describing the amount of a washcoat, or catalytic metal component or other component of a composition, it is convenient to use the mass unit of the component per unit volume of catalytic substrate. Thus, the units, i.e., grams per cubic inch ("g / in"), are used. 3 "), and grams per cubic foot ("g / ft 3 ") means the mass of a component per volume of substrate, including the volume of void space in the substrate, and is expressed in g / ft 3 corresponds to 0.035g / l and 1g / in 3 is equivalent to 61.0237441 g / L. Other units of mass per volume, such as g / L, are sometimes used. It should be noted that these masses per unit volume are typically calculated by weighing the catalytic substrate before and after treatment with the catalytic washcoat composition, and because this treatment includes drying and calcining the catalytic substrate at elevated temperatures, these masses represent the substantially solvent-free catalytic coating when substantially all of the water in the washcoat slurry has been removed.

[0078] Preferably, the total loading of the catalyst article (i.e., oxidation catalyst component and SCR catalyst) on the catalyst substrate is from about 0.5 to about 6 g / in 3 , more preferably about 1 to about 5 g / in 3 , more preferably about 1 to about 3 g / in 3The total active metal loading, excluding the support material (e.g., PGM component only), is preferably about 0.1 to about 200 g / ft for each layer. 3 , more preferably about 0.1 to about 100 g / ft 3 , more preferably about 1 to about 50 g / ft 3 , more preferably about 1 to about 30 g / ft 3 , more preferably about 5 to about 25 g / ft 3 is in the range.

[0079] Alternatively, the total active metal loading, excluding the support material (e.g., PGM components only), is preferably between 5 and 100 g / ft 3 range, preferably 20 to 80 g / ft 3 range, more preferably 30 to 70 g / ft 3 range, more preferably 35 to 55 g / ft 3 range, more preferably 40 to 50 g / ft 3 is in the range.

[0080] Method for Making a Catalyst Composition The preparation of a porous support material impregnated with a platinum group metal can include impregnating a porous support in particulate form with an active metal solution, such as a palladium and / or ruthenium precursor solution. The active metals can be impregnated into the same support particles or into separate support particles using incipient wetness techniques. Preferably, the porous support is a metal oxide. More preferably, the porous support is a refractory metal oxide material.

[0081] Incipient wetness impregnation techniques, also known as capillary impregnation or dry impregnation, are commonly used to synthesize heterogeneous materials, i.e., catalysts. Preferably, the metal precursor is dissolved in an aqueous or organic solution, and the metal-containing solution is then added to a catalyst support containing a pore volume equal to the volume of the added solution. Capillary action draws the solution into the pores of the support. Adding solution in excess of the support's pore volume changes the solution transport from a capillary action process to a much slower diffusion process. The catalyst is then dried and calcined to remove volatile components in the solution, allowing the metal to be deposited on the surface of the catalyst support. The concentration profile of the impregnated material depends on the mass transfer conditions within the pores during impregnation and drying.

[0082] The support particles are typically dried sufficiently to absorb substantially all of the solution and form a wet solid. An aqueous solution of a water-soluble compound or complex of the active metal (i.e., PGM component), such as ruthenium chloride, ruthenium nitrate (e.g., Ru(NO) and its salts), hexaammineruthenium chloride, or a combination thereof, is typically utilized. Aqueous solutions of water-soluble compounds having palladium as the active metal include metal precursors such as palladium nitrate, tetraamminepalladium, palladium acetate, or a combination thereof. After treating the support particles with the active metal solution, the particles can be dried, such as by heat treating the particles at an elevated temperature (e.g., 100-150°C) for a period of time (e.g., 1-3 hours), and then calcined to convert the active metal to a more catalytically active form. An exemplary calcination process involves heat treatment in air at a temperature of approximately 400-550°C for 10 minutes to 3 hours. The above process can be repeated as necessary to achieve the desired level of active metal impregnation. For example, the preparation of SCR catalysts containing metal-promoted molecular sieves is disclosed in U.S. Pat. No. 9,480,976 to Rivas-Cardona et al.; U.S. Pat. No. 9,352,307 to Stiebels et al.; U.S. Pat. No. 9,321,009 to Wan et al.; U.S. Pat. No. 9,199,195 to Andersen et al.; U.S. Pat. No. 9,138,732 to Bull et al.; U.S. Pat. No. 9,011,807 to Mohanan et al.; U.S. Pat. No. 8,715,618 to Turkhan et al.; U.S. Pat. No. 8,293,182 to Boorse et al.; U.S. Pat. No. 8,119,088 to Boorse et al.; U.S. Pat. No. 8,101,146 to Fedeyko et al.; and U.S. Pat. No. 7,220,692 to Marshall et al. For example, the preparation of SCR catalysts containing mixed metal oxides is disclosed in US Pat. No. 4,518,710 to Brennan et al.; US Pat. No. 5,137,855 to Hegedus et al.; US Pat. No. 5,476,828 to Kapteijn et al.; US Pat. No. 8,685,882 to Hong et al.; and US Pat. No. 9,101,908 to Jurng et al.

[0083] Method for coating substrates The aforementioned catalyst composition may be prepared in the form of catalyst particles, as described above. These catalyst particles may be mixed with water to form a slurry for coating a catalyst substrate, such as a honeycomb-type substrate. In addition to the catalyst particles, the slurry may optionally contain a binder in the form of alumina, silica, zirconium acetate, colloidal zirconia, or zirconium hydroxide, an associative thickener, and / or a surfactant (including anionic, cationic, nonionic, or amphiphilic surfactants). Other exemplary binders include boehmite, gamma-alumina or delta / zeta alumina, and silica sol. When present, the binder is typically used in an amount of about 1 to 5 wt. % of the total washcoat loading.

[0084] Therefore, the pH can be adjusted by adding acidic or basic chemical species to the slurry. For example, the pH of the slurry can be adjusted by adding ammonium hydroxide or aqueous nitric acid. A typical pH range for a slurry can be about 3 to 6. The slurry can be milled to reduce particle size and enhance particle mixing. Milling can be performed in a ball mill, continuous mill, or other similar equipment, and the solids content of the slurry can be, for example, about 20 to 60% by weight, more specifically, about 20 to 40% by weight. Preferably, the milled slurry is characterized by a D90 particle size of about 10 to about 40 microns, preferably 10 to about 30 microns, and more preferably about 10 to about 15 microns. D90 is determined using a dedicated particle size analyzer. This device, manufactured by Sympatec in 2010, uses laser diffraction to measure particle size in small volumes of slurry (see, for example, Reference Example 1). The slurry is coated onto a catalyst substrate using any washcoat technique known in the art. Preferably, the catalyst substrate is dipped into or otherwise coated with the slurry one or more times. After this, the coated substrate is preferably dried at an elevated temperature (e.g., 100-150°C) for a period of time (e.g., 10 minutes to 3 hours) and then calcined, for example, by heating at 400-600°C, typically for about 10 minutes to about 3 hours. After drying and calcination, the final washcoat coating layer can be considered substantially solvent-free.

[0085] After calcination, the catalyst loading obtained by the washcoating technique described above can be determined by calculating the difference between the coated and uncoated mass of the substrate. As will be apparent to one skilled in the art, the catalyst loading can be modified by modifying the slurry rheology. Furthermore, the coating / drying / calcining process to produce a washcoat can be repeated as necessary to build the coating to a desired loading level or thickness, meaning that more than one washcoat can be applied. The catalyst composition can be applied as a single layer or in multiple layers, as described above. The catalyst composition can be applied in a single layer (e.g., only layer 14 in Figure 2). Alternatively, the catalyst composition can be applied in multiple layers, each layer having a different composition, as described above.

[0086] Waste Treatment Systems The present invention is x The present invention further relates to an emissions treatment system incorporating the catalytic article of the present invention, which is effective in reducing carbon monoxide and hydrocarbons. The catalytic article of the present invention is typically used in an integrated emissions treatment system, including one or more additional components, for treating exhaust gas emissions, such as those from diesel engines.

[0087] The present invention relates to an exhaust gas treatment system for treating an exhaust gas stream exiting a diesel engine, said exhaust gas treatment system having an upstream end for introducing said exhaust gas stream into said exhaust gas treatment system, said exhaust gas treatment system comprising a catalytic article having an inlet end and an outlet end, said catalytic article being in accordance with the present invention and having a first layer and a second layer in a zone configuration. Equipped with the catalytic article is a first catalytic article in the exhaust gas treatment system downstream of an upstream end of the exhaust gas treatment system, and an inlet end of the catalytic article is disposed upstream of an outlet end of the catalytic article; It further relates to an exhaust gas treatment system.

[0088] Preferably, the exhaust gas treatment system further comprises one or more of a diesel oxidation catalyst, a selective catalytic reduction catalyst, and an ammonia oxidation catalyst located downstream of the catalyst article.

[0089] Preferably, the exhaust gas treatment system further comprises an ammonia oxidation catalyst located downstream of the catalyst article, the ammonia oxidation catalyst having an inlet end and an outlet end, the outlet end of the catalyst article being in fluid communication with the inlet end of the ammonia oxidation catalyst, and no catalyst for treating exhaust gases exiting the second catalyst is located in the exhaust gas treatment system between the outlet end of the catalyst article and the inlet end of the ammonia oxidation catalyst. More preferably, the ammonia oxidation catalyst is as defined in the present invention in paragraph III.

[0090] Preferably, the exhaust gas treatment system further comprises a particulate filter, the particulate filter having an inlet end and an outlet end and located downstream of the catalyst article, preferably the outlet end of the catalyst article being in fluid communication with the inlet end of the particulate filter, and no catalyst for treating the exhaust gas stream exiting the second catalyst being located in the exhaust gas treatment system between the outlet end of the catalyst article and the inlet end of the particulate filter. More preferably, the particulate filter is a catalyzed particulate filter. Alternatively, the particulate filter can be located downstream of the ammonia oxidation catalyst.

[0091] Preferably, the exhaust gas treatment system further comprises an injector for injecting a fluid into the exhaust gas stream exiting the diesel engine, said injector being more preferably located upstream of the catalytic article and downstream of the upstream end of the exhaust gas treatment system. More preferably, the fluid is an aqueous urea solution.

[0092] One exemplary emissions treatment system is illustrated in FIG. 5, which depicts a schematic diagram of emissions treatment system 32. As shown, the emissions treatment system can include multiple catalyst components in series downstream of engine 32, with catalyst article 38 of the present invention always being the first catalyst component in any given series. While FIG. 5 illustrates five catalyst components in series, the total number of catalyst components can vary, and five components is merely an example. Without limitation, Table 1 depicts various exhaust gas treatment system configurations of one or more embodiments. Note that each catalyst component is connected to the next via an exhaust conduit; thus, the engine is upstream of catalyst component A, which is upstream of catalyst component B (if present), which is upstream of catalyst component C (if present), which is upstream of catalyst component D (if present), which is upstream of catalyst component E (if present). When referring to catalyst components A-E in the table, cross-references to FIG. 5 can be made using the same designations. The configurations in Table 1 are merely exemplary and other configurations may be used without departing from the invention.

[0093] The SCR catalysts specified in Table 1 can be any catalyst conventionally used to reduce NOx present in engine exhaust, and typically include mixed metal oxide compositions (e.g., vanadia / titania) or metal ion-exchanged molecular sieve compositions (e.g., Cu and / or Fe promoted molecular sieves).

[0094] References to SCRoF (or SCR over filter) in Table 1 conventionally refer to a particulate or soot filter (eg, a wall-flow filter) that contains an SCR catalyst composition.

[0095] The DOC catalysts specified in Table 1 can be any catalyst conventionally used to combust unburned gaseous and non-volatile hydrocarbons (i.e., SOF) and carbon monoxide to form carbon dioxide and water. The DOC catalysts in Table 1 typically include an oxygen storage component (e.g., ceria) and / or a platinum group metal supported on a refractory metal oxide support (e.g., alumina).

[0096] References to AMOx in Table 1 refer to an ammonia oxidation catalyst, which is typically located downstream of an SCR catalyst used to remove any slipped ammonia from the exhaust gas treatment system. The AMOx catalyst may include a PGM component. Preferably, the AMOx catalyst includes a PGM bottom coat and an SCR top coat.

[0097] The soot filters specified in Table 1 are designed to capture and burn soot. Often, the soot filter is coated with a washcoat layer containing one or more catalysts for burning the captured soot and / or oxidizing emissions in the exhaust gas stream. Generally, the soot combustion catalyst can be any catalyst known for burning soot. The soot combustion catalyst can be, for example, an oxidation catalyst component including one or more precious metal catalysts (e.g., platinum, palladium, and / or rhodium).

[0098] The various exhaust gas emission treatment systems in Table 1 may further include a reductant injector for injection of ammonia precursor 50 and / or an injector for adding hydrocarbons 51 to the exhaust gas stream. In certain embodiments, the reductant injector 50 for introducing a nitrogen-based reductant into the exhaust stream is located immediately upstream of the catalyst article 38, as shown in FIG. 5. Examples of such reductants include ammonia, hydrazine, or any suitable ammonia precursor, such as urea ((NH)CO), ammonium carbonate, ammonium carbamate, ammonium bicarbonate, or ammonium formate. The presence of ammonia or an ammonia precursor in the gas exhaust stream may result in the reduction of NO when the gas is exposed to the catalyst composition of the catalyst article 38. xThe reduction of hydrocarbons to N2 and water is promoted. The reductant injector 50 can be located at any point upstream of the SCR catalyst article, as shown in the figure, and need not necessarily be located upstream of all catalyst articles. The location of the reductant injector 50 will depend on the location of the SCR catalyst. Preferably, an HC injector 51 may also be introduced upstream of the catalyst article 38. Preferably, the HC injector 51, if present, is located upstream or downstream of the injector 50. The catalyst article 38 oxidizes the introduced hydrocarbons into the gas exhaust stream, generating temperatures sufficient to remove pollutants from the catalyst article and downstream components. The hydrocarbons promote the release of pollutants from the catalyst article, thereby restoring the catalytic activity of the catalyst article. Additionally, desulfation and / or removal of amine-containing (e.g., urea) deposits can be performed during a regeneration cycle. Hydrocarbons can be introduced directly into the gas exhaust stream from the engine. An engine management system controlling the engine can periodically add fuel directly to the engine's exhaust gas stream. An optional second hydrogen injector can be added to the exhaust gas treatment system configuration with the DOC catalyst component, in which case the optional second hydrocarbon injector is located immediately upstream of the DOC catalyst component. As will be appreciated by those skilled in the art, in the configurations listed in Table 1, one or more of components A, B, C, D, or E can be disposed on a particulate filter, such as a wall-flow filter, or on a flow-through honeycomb substrate. The engine exhaust system can include one or more catalyst compositions mounted in a position near the engine (close-coupled, or CC) with an additional catalyst composition located below the vehicle body (underfloor, or UF). Preferably, component A (e.g., the catalyst article of the present invention) is located in the closest position, meaning that component A is the first catalyst in the engine's exhaust gas treatment system, with the remaining components being UFs.

[0099] [Table 1]

[0100] II. Exhaust Gas Treatment System Surprisingly, it has also been found that an exhaust gas treatment system according to the present invention, as described below, for treating an exhaust gas stream exiting a diesel engine is cost-effective and allows for avoiding engine measures such as increased exhaust gas temperatures, while at the same time being resistant to HC poisoning and preventing sulfation in order to maintain sufficient de-NOx to meet environmental requirements.

[0101] Accordingly, the present invention provides an exhaust gas treatment system for treating an exhaust gas stream exiting a diesel engine, said exhaust gas treatment system having an upstream end for introducing said exhaust gas stream into said exhaust gas treatment system, said exhaust gas treatment system comprising: (i) a first catalyst having an inlet end and an outlet end and comprising a coating disposed on a substrate, the coating comprising palladium supported on an oxide material comprising zirconium, and further comprising one or more of vanadium oxide and a zeolite material comprising one or more of copper and iron; or a first catalyst having an inlet end and an outlet end, the first catalyst being a catalyst article according to the present invention; (ii) a second catalyst having an inlet end and an outlet end and comprising a coating disposed on a substrate, the coating comprising a platinum group metal supported on an oxide material, and further comprising one or more of vanadium oxide, tungsten oxide, and a zeolite material comprising one or more of copper and iron. Equipped with the first catalyst according to (i) is a first catalyst of the exhaust gas treatment system downstream of an upstream end of the exhaust gas treatment system, and an inlet end of the first catalyst is located upstream of an outlet end of the first catalyst; The present invention further relates to an exhaust gas treatment system in which a second catalyst according to (ii) is located downstream of the first catalyst according to (i), and the inlet end of the second catalyst is disposed upstream of the outlet end of the second catalyst.

[0102] Preferably, the outlet end of the first catalyst according to (i) is in fluid communication with the inlet end of the second catalyst according to (ii), and no catalyst for treating the exhaust gas flow exiting the first catalyst is located in the exhaust gas treatment system between the outlet end of the first catalyst according to (i) and the inlet end of the second catalyst according to (ii).

[0103] Preferably, the first catalyst comprises a hydrocarbon (HC) oxidizing component and a nitrogen oxide (NOx) reducing component.

[0104] With regard to the oxide material contained in the first catalyst coating, it is preferred that 90 to 100% by mass, more preferably 95 to 100% by mass, more preferably 99 to 100% by mass of the oxide material contained in the first catalyst coating consists of zirconium and oxygen, preferably zirconia.

[0105] Preferably, the first catalytic coating according to (i) comprises a zeolitic material containing one or more of copper and iron.

[0106] In the context of the present invention, the term "zeolitic material" refers to any zeolite material having a framework structure type ABW, ACO, AEI, AEL, AEN, AET, AFG, AFI, AFN, AFO, AFR, AFS, AFT, AFV, AFX, AFY, AHT, ANA, APC, APD, AST, ASV, ATN, ATO, ATS, ATT, ATV, AVL, AWO, AWW, BCT, BEA, BEC, BIK, BOF, BOG, BOZ, BPH, BRE, BSV, CAN, CAS, CDO, CFI, CGF, CGS, CHA, -CHI, -CLO, CON, CSV, CZP, DAC, DDR, DFO, DFT, DOH, DON, EAB, EDI, EEI, EMT, EON, EPI, ERI, ESV, ETR, EUO, * -EWT, EZT, FAR, FAU, FER, FRA, GIS, GIU, GME, GON, GOO, HEU, IFO, IFR, -IFU, IFW, IFY, IHW, IMF, IRN, IRR, -IRY, ISV, ITE, ITG, ITH, *-ITN, ITR, ITT, -ITV, ITW, IWR, IWS, IWV, IWW, JBW, JNT, JOZ, JRY, JSN, JSR, JST, JSW, KFI, LAU, LEV, LIO, -LIT, LOS, LOV, LTA, LTF, LTJ, LTL, LTN, MAR, MAZ, MEI, MEL, MEP, MER, MFI, MFS, MON, MOR, MOZ, * MRE, MSE, MSO, MTF, MTN, MTT, MTW, MVY, MWF, MWW, NAB, NAT, NES, NON, NPO, NPT, NSI, OBW, OFF, OKO, OSI, OSO, OWE, -PAR, PAU, PCR, PHI, PON, POS, PSI, PUN, RHO, -RON, RRO, RSN, RTE, RTH, RUT, RWR, RWY, SAF, SAO, SAS, SAT, SAV, SBE, SBN, SBS, SBT, SEW, SFE, SFF, SFG, SFH, SFN, SFO, SFS, * SFV, SFW, SGT, SIV, SOD, SOF, SOS, SSF, * -SSO, SSY, STF, STI, * STO, STT, STW, -SVR, SVV, SZR, TER, THO, TOL, TON, TSC, TUN, UEI, UFI, UOS, UOV, UOZ, USI, UTL, UWY, VET, VFI, VNI, VSV, WEI, -WEN, YUG, ZON, and zeolite materials preferably having two or more of them and two or more of their mixed types.

[0107] There are no particular limitations regarding the zeolite material contained in the coating of the first catalyst, provided that the zeolite material is suitable for the intended use of the first catalyst in the exhaust gas treatment system of the present invention. Preferred zeolite materials are those having a framework structure of type AEI, GME, CHA, MFI, BEA, FAU, MOR, or a mixture of two or more thereof, preferably type AEI, CHA, BEA, or a mixture of two or more thereof. More preferably, the zeolite material contained in the coating of the first catalyst has a framework structure of type CHA or AEI, more preferably type CHA. Zeolite materials having a framework structure of type CHA include, for example, zeolite SSZ-13 and zeolite SAPO-34, with SSZ-13 being preferred.

[0108] In the context of the present invention, it is preferred that the zeolitic material comprised in the coating of the first catalyst, more preferably a zeolitic material having a framework structure type CHA, has an average crystal size of at least 0.5 micrometers, preferably in the range of 0.5 to 1.5 micrometers, more preferably in the range of 0.6 to 1.0 micrometers, more preferably in the range of 0.6 to 0.8 micrometers, as determined by scanning electron microscopy.

[0109] Preferably, the zeolitic material contained in the coating of the first catalyst contains copper, and the amount of copper contained in the zeolitic material, calculated as CuO, is preferably in the range of 0.1 to 10.0% by mass, more preferably in the range of 2.0 to 7.0% by mass, more preferably in the range of 2.5 to 5.5% by mass, more preferably in the range of 2.5 to 3.5% by mass, based on the total mass of the zeolitic material. More preferably, the amount of iron contained in the zeolitic material, calculated as Fe2O3, is in the range of 0 to 0.01% by mass, more preferably in the range of 0 to 0.0 ... based on the total mass of the zeolitic material.

[0110] Preferably, 95 to 100% by mass, more preferably 98 to 100% by mass, more preferably 99 to 100% by mass of the framework structure of the zeolitic material consists of one or more of Si, Al, O, and optionally H and P, and the molar ratio of Si to Al, calculated as molar SiO2:Al2O3, in the framework structure is preferably in the range of 2:1 to 50:1, more preferably in the range of 4:1 to 45:1, more preferably in the range of 10:1 to 40:1, more preferably in the range of 20:1 to 35:1.

[0111] Preferably, the zeolite material contained in the coating of the first catalyst contains iron, and the amount of iron contained in the zeolite material, calculated as Fe2O3, is preferably in the range of 0.1 to 10.0 mass%, more preferably 1.0 to 7.0 mass%, more preferably 2.5 to 5.5 mass%, based on the total mass of the zeolite material. More preferably, 95 to 100 mass%, more preferably 98 to 100 mass%, more preferably 99 to 100 mass% of the framework structure of the zeolite material consists of any one or more of Si, Al, O, H, and P, and the molar ratio of Si to Al in the framework structure, calculated as SiO2:Al2O3, by molar, is preferably in the range of 2:1 to 50:1, more preferably 4:1 to 45:1, more preferably 10:1 to 40:1, more preferably 20:1 to 35:1.

[0112] Preferably, the first catalytic coating further comprises a metal oxide binder, preferably comprising one or more of zirconia, alumina, titania, silica, and an oxide mixture comprising two or more of Zr, Al, Ti, and Si, more preferably one or more of alumina and zirconia, more preferably zirconia. More preferably, the first catalytic coating has a coating density of 0.02 to 0.2 g / g / in 3 in the range of 0.07 to 0.15 g / g / in 3 The binder comprises a metal oxide at a loading in the range of 0.1 to 1.0.

[0113] According to the present invention, the coating of the first catalyst according to (i) comprises vanadium oxide, preferably one or more of vanadium(V) oxide and vanadium(IV) oxide, and optionally the vanadium oxide comprises one or more of tungsten, iron and antimony.

[0114] Preferably, the vanadium oxide is supported on an oxide material comprising one or more of titanium, silicon and zirconium, preferably on an oxide material comprising one or more of titanium and silicon, more preferably on an oxide material comprising one or more of titania and silica, more preferably on titania, the titania optionally containing one or more of tungsten and silicon.

[0115] With regard to the substrate of the first catalyst according to (i), it is preferred that said substrate comprises, preferably consists of, a ceramic or metallic material.

[0116] There are no particular limitations regarding the substrate of the first catalyst, which may include, or preferably consist of, a ceramic substrate, provided that the substrate is suitable for the intended use of the first catalyst in the exhaust gas treatment system of the present invention. Preferably, the ceramic material comprises, or consists of, one or more of alumina, silica, silicates, aluminosilicates, preferably cordierite or mullite, aluminotitanate, silicon carbide, zirconia, magnesia, preferably spinel and titania, more preferably one or more of silicon carbide and cordierite, more preferably cordierite.

[0117] There are no particular limitations regarding the substrate of the first catalyst, which may comprise, or preferably consist of, a metallic substrate, provided that the substrate is suitable for the intended use of the first catalyst in the exhaust gas treatment system of the present invention. It is preferred that the metallic material comprises, or more preferably consists of, oxygen and one or more of iron, chromium, and aluminum.

[0118] The substrate of the first catalyst according to (i) is preferably a monolith, preferably a honeycomb monolith, more preferably a flow-through honeycomb monolith.

[0119] According to the present invention, the substrate of the first catalyst has a substrate length, and the coating of the first catalyst is preferably disposed on 20 to 100% of the substrate length, preferably 50 to 100%, more preferably 75 to 100%, more preferably 95 to 100%, more preferably 99 to 100%.

[0120] Generally, there is no limitation on the palladium loading contained in the first catalyst coating, provided that the palladium loading is suitable for the intended use of the first catalyst in the exhaust gas treatment system. Preferably, the first catalyst coating has a palladium loading of 0.035 to 2.82 g / L (1 to 80 g / ft 3 ), more preferably in the range of 0.53 to 2.12 g / l (15 to 60 g / ft 3 ), more preferably in the range of 0.71 to 1.77 g / l (20 to 50 g / ft 3 ), more preferably in the range of 0.88 to 1.59 g / l (25 to 45 g / ft 3 ), more preferably in the range of 0.88 to 1.24 g / l (25 to 35 g / ft 3 ) containing palladium in a loading range.

[0121] With respect to palladium loading, there is no limitation as to the loading of the zeolite material contained in the first catalyst coating, provided that the loading of the zeolite material is suitable for the intended use in the first catalyst in the exhaust gas treatment system. Preferably, the first catalyst coating has a palladium loading of 61.02 to 274.61 g / L (1.0 to 4.5 g / g / in). 3 ), more preferably in the range of 91.54 to 244.10 g / L (1.5 to 4.0 g / in 3 ), more preferably in the range of 122.05 to 183.07 g / L (2.0 to 3.0 g / in 3 ), more preferably in the range of 128.15 to 170.87 g / L (2.1 to 2.8 g / in 3 ), more preferably in the range of 128.15 to 158.66 g / L (2.1 to 2.6 g / in 3 ) with a loading of zeolite material in the range of 0.1 to 1.0.

[0122] Generally, there is no limitation regarding the vanadium oxide loading contained in the first catalyst coating, provided that the vanadium oxide loading is suitable for the intended use of the first catalyst in the exhaust gas treatment system. Preferably, the first catalyst coating has a vanadium oxide loading of 122.04 to 366.14 g / L (2.0 to 6.0 g / g / in 3 ), more preferably in the range of 183.07 to 335.63 g / L (3.0 to 5.5 g / in 3 ), more preferably in the range of 244.1 to 305.12 g / L (4.0 to 5.0 g / in 3 ) containing vanadium oxide in a loading range.

[0123] According to the present invention, 95-100% by weight, more preferably 98-100% by weight, more preferably 99-100% by weight, more preferably 99.5-100% by weight of the coating of the first catalyst preferably comprises palladium supported on an oxide material, preferably consisting of said palladium, and 99-100% by weight of said oxide material preferably consisting of zirconium and oxygen, preferably zirconia, a copper-containing zeolitic material having a type CHA framework structure, and preferably a metal oxide binder as defined in the present invention.

[0124] Accordingly, the present invention provides an exhaust gas treatment system for treating an exhaust gas stream exiting a diesel engine, said exhaust gas treatment system having an upstream end for introducing said exhaust gas stream into said exhaust gas treatment system, said exhaust gas treatment system comprising: (i) A first catalyst having an inlet end and an outlet end, comprising a coating disposed on a substrate, the coating comprising palladium supported on an oxide material comprising zirconium, and further comprising a zeolitic material comprising one or more of copper and iron, wherein 95 to 100 wt. %, preferably 98 to 100 wt. %, more preferably 99 to 100 wt. %, more preferably 99.5 to 100 wt. % of the coating of the first catalyst comprises palladium supported on an oxide material, preferably consisting of said palladium, and 99 to 100 wt. % of the oxide material consists of zirconium and oxygen, preferably zirconia, a copper-containing zeolitic material having a Type CHA framework structure, and a metal oxide binder material, preferably as defined in the present invention. (ii) a second catalyst having an inlet end and an outlet end and comprising a coating disposed on a substrate, the coating comprising a platinum group metal supported on an oxide material, and further comprising one or more of vanadium oxide, tungsten oxide, and a zeolite material comprising one or more of copper and iron. Equipped with the first catalyst according to (i) is a first catalyst of the exhaust gas treatment system downstream of an upstream end of the exhaust gas treatment system, and an inlet end of the first catalyst is located upstream of an outlet end of the first catalyst; The present invention preferably relates to an exhaust gas treatment system in which the second catalyst according to (ii) is located downstream of the first catalyst according to (i), and the inlet end of the second catalyst is arranged upstream of the outlet end of the second catalyst.

[0125] According to the present invention, 95 to 100% by weight, more preferably 98 to 100% by weight, more preferably 99 to 100% by weight, more preferably 99.5 to 100% by weight of the coating of the first catalyst preferably comprises, preferably consists of, palladium supported on an oxide material, and 99 to 100% by weight of said oxide material consists of zirconium and oxygen, preferably zirconia, and vanadium oxide supported on titania, the titania optionally containing one or more of tungsten and silicon.

[0126] Accordingly, the present invention provides an exhaust gas treatment system for treating an exhaust gas stream exiting a diesel engine, said exhaust gas treatment system having an upstream end for introducing said exhaust gas stream into said exhaust gas treatment system, said exhaust gas treatment system comprising: (i) A first catalyst having an inlet end and an outlet end, comprising a coating disposed on a substrate, the coating comprising palladium supported on an oxide material comprising zirconium, and further comprising vanadium oxide, wherein 95 to 100%, preferably 98 to 100%, more preferably 99 to 100%, more preferably 99.5 to 100%, by weight, of the coating of the first catalyst comprises, preferably consists of, palladium supported on an oxide material, and 99 to 100%, by weight, of the oxide material comprises zirconium and oxygen, preferably zirconia, and vanadium oxide supported on titania, the titania optionally containing one or more of tungsten and silicon. (ii) a second catalyst having an inlet end and an outlet end and comprising a coating disposed on a substrate, the coating comprising a platinum group metal supported on an oxide material, and further comprising one or more of vanadium oxide, tungsten oxide, and a zeolite material comprising one or more of copper and iron. Equipped with the first catalyst according to (i) is a first catalyst of the exhaust gas treatment system downstream of an upstream end of the exhaust gas treatment system, and an inlet end of the first catalyst is located upstream of an outlet end of the first catalyst; The present invention preferably relates to an exhaust gas treatment system in which the second catalyst according to (ii) is located downstream of the first catalyst according to (i), and the inlet end of the second catalyst is arranged upstream of the outlet end of the second catalyst.

[0127] According to the present invention, the first catalyst according to (i) preferably has a selective catalytic reduction (SCR) component and a diesel oxidation component.

[0128] Preferably, 0-0.0035 g / l, more preferably 0-0.00035 g / l, more preferably 0-0.000035 g / l of one or more of platinum, iridium, osmium and rhodium is included in the first catalyst coating, more preferably 0-0.000035 g / l of platinum, iridium, osmium and rhodium is included in the first catalyst coating.

[0129] Preferably, the first catalytic coating is platinum-free, more preferably platinum- and rhodium-free, more preferably platinum, rhodium, iridium, and osmium-free.

[0130] Preferably, 0 to 2 wt %, more preferably 0 to 1 wt %, more preferably 0 to 0.1 wt % of the palladium-supporting oxide material contained in the first catalyst coating consists of ceria and alumina, and more preferably, 0 to 0.1 wt % of the oxide material contained in the first catalyst coating consists of ceria, alumina, titania, lanthana and baria.

[0131] Preferably, the palladium-supporting oxide material contained in the coating of the first catalyst is free of ceria and alumina, more preferably free of ceria, alumina and titania, more preferably free of ceria, alumina, titania, lanthana and baria.

[0132] With respect to the first catalyst, it is alternatively preferred that the first catalyst is a catalyst article according to the present invention, as defined in paragraph I. More preferably, the first catalyst comprises a single layer or a first (upper or lower) layer and a second (upper or lower) layer.

[0133] With regard to the first catalyst, it is alternatively preferred that the first catalyst is a second catalyst according to (ii) as defined in paragraph III.

[0134] According to the present invention, the second catalyst according to (ii) preferably comprises a nitrogen oxide (NOx) reducing component and an ammonia oxidizing component.

[0135] Preferably, the second catalyst according to (ii) is an ammonia oxidation (AMOX) catalyst.

[0136] Preferably, the second catalytic coating according to (ii) comprises a zeolitic material containing one or more of copper and iron.

[0137] There are no particular limitations regarding the zeolite material included in the coating of the second catalyst, provided that the zeolite material is suitable for the intended use of the second catalyst in the exhaust gas treatment system of the present invention. Generally, the zeolite material contained in the coating of the second catalyst is of the type ABW, ACO, AEI, AEL, AEN, AET, AFG, AFI, AFN, AFO, AFR, AFS, AFT, AFV, AFX, AFY, AHT, ANA, APC, APD, AST, ASV, ATN, ATO, ATS, ATT, ATV, AVL, AWO, AWW, BCT, BEA, BEC, BIK, BOF, BOG, BOZ, BPH, BRE, BSV, CAN, CAS, CDO, CFI, CGF, CGS, CHA, -CHI, -CLO, CON, CSV, CZP, DAC, DDR, DFO, DFT, DOH, DON, EAB, EDI, EEI, EMT, EON, EPI, ERI, ESV, ETR, EUO, * -EWT, EZT, FAR, FAU, FER, FRA, GIS, GIU, GME, GON, GOO, HEU, IFO, IFR, -IFU, IFW, IFY, IHW, IMF, IRN, IRR, -IRY, ISV, ITE, ITG, ITH, * -ITN, ITR, ITT, -ITV, ITW, IWR, IWS, IWV, IWW, JBW, JNT, JOZ, JRY, JSN, JSR, JST, JSW, KFI, LAU, LEV , LIO, -LIT, LOS, LOV, LTA, LTF, LTJ, LTL, LTN, MAR, MAZ, MEI, MEL, MEP, MER, MFI, MFS, MON, MOR, MOZ, * MRE, MSE, MSO, MTF, MTN, MTT, MTW, MVY, MWF, MWW, NAB, NAT, NES, NON, NPO, NPT, NSI, OBW, OFF, OKO, OSI, OSO, OWE, -PAR, PAU, PCR, PHI, PON, PO S, PSI, PUN, RHO, -RON, RRO, RSN, RTE, RTH, RUT, RWR, RWY, SAF, SAO, SAS, SAT, SAV, SBE, SBN, SBS, SBT, SEW, SFE, SFF, SFG, SFH, SFN, SFO, SFS, * SFV, SFW, SGT, SIV, SOD, SOF, SOS, SSF,* -SSO, SSY, STF, STI, * The zeolite material contained in the coating of the second catalyst may have a framework structure of STO, STT, STW, -SVR, SVV, SZR, TER, THO, TOL, TON, TSC, TUN, UEI, UFI, UOS, UOV, UOZ, USI, UTL, UWY, VET, VFI, VNI, VSV, WEI, -WEN, YUG, ZON, a mixture of two or more of these, or a mixture of two or more of these. Preferably, the zeolite material contained in the coating of the second catalyst has a framework structure of type AEI, GME, CHA, MFI, BEA, FAU, or MOR, or a mixture of two or more of these, more preferably a framework structure of type AEI, CHA, or BEA, or a mixture of two or more of these, more preferably a framework structure of type CHA or AEI, and more preferably a framework structure of type CHA. Zeolite materials having a framework structure type CHA include, for example, zeolite SSZ-13 and zeolite SAPO-34, with SSZ-13 being preferred.

[0138] In the context of the present invention, it is preferred that the zeolitic material comprised in the coating of the second catalyst, more preferably a zeolitic material having a framework structure type CHA, has an average crystal size of at least 0.5 micrometers, preferably in the range of 0.5 to 1.5 micrometers, more preferably in the range of 0.6 to 1.0 micrometers, more preferably in the range of 0.6 to 0.8 micrometers, as determined by scanning electron microscopy.

[0139] Preferably, the zeolitic material contained in the second catalyst coating contains copper, and the amount of copper contained in the zeolitic material, calculated as CuO, is preferably in the range of 0.1 to 10.0% by mass, more preferably in the range of 2.0 to 7.0% by mass, more preferably in the range of 2.5 to 5.5% by mass, more preferably in the range of 2.5 to 3.5% by mass, based on the total mass of the zeolitic material. More preferably, the amount of iron contained in the zeolitic material, calculated as Fe2O3, is in the range of 0 to 0.01% by mass, more preferably in the range of 0 to 0.0 ... based on the total mass of the zeolitic material.

[0140] Preferably, 95 to 100% by mass, more preferably 98 to 100% by mass, more preferably 99 to 100% by mass of the framework structure of the zeolitic material consists of one or more of Si, Al, O, and optionally H and P, and the molar ratio of Si to Al, calculated as molar SiO2:Al2O3, in the framework structure is preferably in the range of 2:1 to 50:1, more preferably in the range of 4:1 to 40:1, more preferably in the range of 10:1 to 40:1, more preferably in the range of 20:1 to 35:1.

[0141] Preferably, the zeolitic material contained in the coating of the second catalyst comprises iron, the amount of iron contained in the zeolitic material, calculated as Fe2O3, being preferably in the range of 0.1 to 10.0 wt%, more preferably 1.0 to 7.0 wt%, more preferably 2.5 to 5.5 wt%, based on the total weight of the zeolitic material. Preferably, 95 to 100 wt%, more preferably 98 to 100 wt%, more preferably 99 to 100 wt% of the framework structure of the zeolitic material consists of one or more of Si, Al, O, and optionally H and P, and the molar ratio of Si to Al in the framework structure, calculated as SiO2:Al2O3, by mole, is preferably in the range of 2:1 to 50:1, more preferably 4:1 to 40:1, more preferably 10:1 to 40:1, more preferably 20:1 to 35:1.

[0142] Preferably, the second catalytic coating further comprises a metal oxide binder, preferably comprising one or more of zirconia, alumina, titania, silica, and an oxide mixture comprising two or more of Zr, Al, Ti, and Si, more preferably one or more of alumina and zirconia, more preferably zirconia. More preferably, the second catalytic coating has a binder content of 1.22 to 12.20 g / L (0.02 to 0.2 g / in). 3 ), more preferably in the range of 4.27 to 9.15 g / L (0.07 to 0.15 g / in 3 ) containing a metal oxide binder at a loading in the range of 0.1 to 1.0 wt.

[0143] Preferably, the platinum group metal contained in the second catalytic coating is one or more of platinum, palladium and rhodium, preferably one or more of platinum and palladium.

[0144] Preferably, the platinum group metal contained in the second catalyst coating is a mixture of platinum and palladium, and more preferably, the mass ratio of platinum to palladium contained in the second catalyst coating, calculated as elemental platinum and elemental palladium, is in the range of 1:1 to 30:1, more preferably in the range of 5:1 to 20:1, more preferably in the range of 8:1 to 12:1, more preferably in the range of 9:1 to 11:1.

[0145] Alternatively, the platinum group metal included in the second catalytic coating is platinum.

[0146] According to the present invention, it is preferred that the platinum group metal supporting oxide material contained in the coating of the second catalyst comprises, preferably consists of, one or more of alumina, zirconia, silica, titania and ceria, preferably one or more of alumina, silica and zirconia, more preferably one or more of zirconia and alumina.

[0147] Preferably, 20 to 100% by mass, more preferably 40 to 100% by mass, more preferably 60 to 100% by mass, more preferably 70 to 90% by mass, more preferably 75 to 85% by mass of the platinum group metal-supporting oxide material contained in the second catalyst coating consists of alumina.

[0148] According to the present invention, the second catalytic coating according to (ii) comprises vanadium oxide, preferably one or more of vanadium(V) oxide and vanadium(IV) oxide, and optionally the vanadium oxide comprises one or more of tungsten, iron and antimony.

[0149] Preferably, the vanadium oxide is supported on an oxide material comprising one or more of titanium, silicon and zirconium, more preferably on an oxide material comprising one or more of titanium and silicon, more preferably on an oxide material comprising one or more of titania and silica, more preferably on titania, the titania optionally comprising one or more of tungsten and silicon.

[0150] The second catalytic coating comprises tungsten oxide, preferably tungsten trioxide, optionally comprising one or more of iron and antimony, preferably supported on an oxide material comprising one or more of titanium and zirconium, more preferably on an oxide material comprising one or more of titania and zirconia, more preferably on titania.

[0151] Preferably, the second catalytic coating comprises vanadium oxide and tungsten oxide, the tungsten oxide being tungsten trioxide, the vanadium oxide preferably being supported on an oxide material comprising one or more of titanium, silicon and zirconium, preferably on an oxide material comprising one or more of titanium and silicon, more preferably on an oxide material comprising one or more of titania and zirconia, more preferably on titania, the titania optionally containing one or more of tungsten and silicon, and the tungsten oxide preferably being supported on an oxide material comprising one or more of titanium and zirconium, more preferably on an oxide material comprising one or more of titania and zirconia, more preferably on titania.

[0152] With regard to the substrate of the second catalyst, it is preferred that said substrate comprises, and more preferably consists of, a ceramic or metallic material.

[0153] There are no particular limitations regarding the substrate of the second catalyst, which may include, or preferably consist of, a ceramic substrate, provided that the substrate is suitable for the intended use of the second catalyst in the exhaust gas treatment system of the present invention. Preferably, the ceramic material preferably comprises, or more preferably consists of, one or more of alumina, silica, silicates, aluminosilicates, preferably cordierite or mullite, aluminotitanate, silicon carbide, zirconia, magnesia, preferably spinel and titania, more preferably one or more of silicon carbide and cordierite, more preferably cordierite.

[0154] There are no particular limitations regarding the substrate of the second catalyst, which may include, or preferably consist of, a metallic substrate, provided that the substrate is suitable for the intended use of the second catalyst included in the exhaust gas treatment system of the present invention. It is preferred that the metallic material preferably includes, and more preferably consists of, oxygen and one or more of iron, chromium, and aluminum.

[0155] The substrate of the second catalyst is preferably a monolith, preferably a honeycomb monolith, more preferably a flow-through honeycomb monolith.

[0156] Preferably, the second catalyst substrate has a substrate length, and the second catalyst coating is disposed on 20 to 100% of the substrate length, preferably 50 to 100%, more preferably 75 to 100%, more preferably 95 to 100%, more preferably 99 to 100%.

[0157] Generally, there are no particular limitations regarding the platinum group metal loading in the second catalyst coating, provided that the loading is suitable for the intended use of the second catalyst in the exhaust gas treatment system of the present invention. Preferably, the loading is between 0.035 and 0.53 g / L (1 to 15 g / ft), calculated as elemental platinum group metal. 3 ), more preferably in the range of 0.11 to 0.35 g / l (3 to 10 g / ft 3 ), more preferably in the range of 0.16 to 0.32 g / l (4.5 to 9.0 g / ft 3 ), more preferably in the range of 0.26 to 0.30 g / l (7.5 to 8.5 g / ft 3 ) platinum group metal loadings in the range.

[0158] Generally, there are no particular limitations regarding the loading of zeolitic material contained in the second catalyst coating, provided that said loading is suitable for the intended use of the second catalyst in the exhaust gas treatment system of the present invention. Preferably, the second catalyst coating has a loading of 30.51 to 335.63 g / L (0.5 to 5.5 g / g / in). 3 ), more preferably in the range of 91.54 to 305.12 g / L (1.5 to 5.0 g / in 3 ), more preferably in the range of 122.05 to 244.09 g / L (2.0 to 4.0 g / in 3 ), more preferably in the range of 122.05 to 213.58 g / L (2.0 to 3.5 g / in 3 ) with a loading of zeolite material in the range of 0.1 to 1.0.

[0159] According to the present invention, there is no particular limitation regarding the loading of vanadium oxide contained in the second catalyst coating, provided that said loading is suitable for the intended use of the second catalyst in the exhaust gas treatment system of the present invention. Preferably, the second catalyst coating has a vanadium oxide loading of 122.04 to 366.14 g / L (2.0 to 6.0 g / g / in). 3 ), more preferably in the range of 183.07 to 335.63 g / L (3.0 to 5.5 g / in 3 ), more preferably in the range of 244.1 to 305.12 g / L (4.0 to 5.0 g / in 3 ) containing one or more of vanadium oxide and tungsten oxide.

[0160] According to the present invention, the coating of the second catalyst preferably comprises, preferably consists of, an oxide material comprising a mixture of zirconia and alumina, a mixture of platinum and palladium (the mass ratio of platinum to palladium, calculated as Pt:Pd, is preferably in the range of 5:1 to 15:1, more preferably in the range of 8:1 to 12:1, more preferably in the range of 9:1 to 11:1), a zeolitic material having a framework structure of type CHA and containing copper, and a metal oxide binder, preferably as defined in the present invention. More preferably, 95 to 100% by weight, more preferably 98 to 100% by weight, more preferably 99 to 100% by weight, more preferably 99.5 to 100% by weight of the coating of the second catalyst comprises a mixture of platinum and palladium supported on an oxide material comprising a mixture of zirconia and alumina (the mass ratio of platinum to palladium, calculated as Pt:Pd, is preferably in the range of 5:1 to 15:1, more preferably in the range of 8:1 to 12:1, more preferably in the range of 9:1 to 11:1), a zeolite material having a type CHA framework structure and containing copper, and a metal oxide binder material, preferably as defined in the present invention.

[0161] According to the present invention, the first catalyst coating comprises, preferably consists of, palladium supported on an oxide material comprising zirconium, preferably zirconium and oxygen, more preferably zirconia, a zeolitic material having a type CHA framework structure and comprising copper, and a metal oxide binder preferably as defined in the present invention; and the second catalyst coating comprises, preferably consists of, a mixture of platinum and palladium supported on an oxide material comprising a mixture of zirconia and alumina (the mass ratio of platinum to palladium, calculated as Pt:Pd, is preferably in the range of 5:1 to 15:1, more preferably in the range of 8:1 to 12:1, more preferably in the range of 9:1 to 11:1), a zeolitic material having a type CHA framework structure and comprising copper, and a metal oxide binder preferably as defined in the present invention.

[0162] Accordingly, the present invention provides an exhaust gas treatment system for treating an exhaust gas stream exiting a diesel engine, said exhaust gas treatment system having an upstream end for introducing said exhaust gas stream into said exhaust gas treatment system, said exhaust gas treatment system comprising: (i) a first catalyst having an inlet end and an outlet end and comprising a coating disposed on a substrate, the coating comprising, preferably consisting of, palladium supported on an oxide material comprising zirconium, preferably consisting of zirconium and oxygen, more preferably consisting of zirconia, a zeolite material having a type CHA framework structure and comprising copper, and a metal oxide binder material as defined in the present invention; (ii) a second catalyst having an inlet end and an outlet end, comprising a coating disposed on a substrate, the coating comprising, preferably consisting of, a mixture of platinum and palladium supported on an oxide material comprising a mixture of zirconia and alumina (the mass ratio of platinum to palladium, calculated as Pt:Pd, is preferably in the range of 5:1 to 15:1, more preferably in the range of 8:1 to 12:1, more preferably in the range of 9:1 to 11:1), a zeolitic material having a Type CHA framework structure and containing copper, and a metal oxide binder material, preferably as defined herein; Equipped with the first catalyst according to (i) is a first catalyst of the exhaust gas treatment system downstream of an upstream end of the exhaust gas treatment system, and an inlet end of the first catalyst is located upstream of an outlet end of the first catalyst; The present invention preferably relates to an exhaust gas treatment system in which the second catalyst according to (ii) is located downstream of the first catalyst according to (i), and the inlet end of the second catalyst is arranged upstream of the outlet end of the second catalyst.

[0163] More preferably, 95 to 100% by weight, more preferably 98 to 100% by weight, more preferably 99 to 100% by weight, more preferably 99.5 to 100% by weight of the coating of the first catalyst comprises palladium supported on an oxide material consisting of zirconia, a zeolitic material having a framework structure type CHA containing copper, and a metal oxide binder preferably as defined in the present invention; and 95 to 100% by weight, preferably 98 to 100% by weight, more preferably 99 to 100% by weight, more preferably 99.5 to 100% by weight of the coating of the second catalyst comprises a mixture of platinum and palladium supported on an oxide material comprising a mixture of zirconia and alumina (the mass ratio of platinum to palladium, calculated as Pt:Pd, is preferably in the range of 5:1 to 15:1, more preferably in the range of 8:1 to 12:1, more preferably in the range of 9:1 to 11:1), a zeolitic material having a framework structure of type CHA and containing copper, and a metal oxide binder preferably as defined in the present invention.

[0164] Alternatively, the first catalytic coating comprises, preferably consists of, palladium supported on an oxide material comprising zirconium, preferably zirconium and oxygen, more preferably zirconia, and vanadium oxide supported on titania, the vanadium oxide more preferably being one or more of vanadium(V) oxide and vanadium(IV) oxide, the vanadium oxide optionally comprising one or more of tungsten, iron and antimony, the titania optionally containing one or more of tungsten and silicon; and The second catalyst coating preferably comprises, preferably consists of, a mixture of platinum and palladium supported on an oxide material comprising a mixture of zirconia and alumina (the mass ratio of platinum to palladium, calculated as Pt:Pd, is preferably in the range of 5:1 to 15:1, more preferably in the range of 8:1 to 12:1, more preferably in the range of 9:1 to 11:1), a zeolite material having a type CHA framework structure and containing copper, and a metal oxide binder material, preferably as defined in the present invention.

[0165] Accordingly, the present invention provides an exhaust gas treatment system for treating an exhaust gas stream exiting a diesel engine, said exhaust gas treatment system having an upstream end for introducing said exhaust gas stream into said exhaust gas treatment system, said exhaust gas treatment system comprising: (i) a first catalyst having an inlet end and an outlet end, comprising a coating disposed on a substrate, the coating comprising, preferably consisting of, palladium supported on an oxide material comprising zirconium, preferably zirconium and oxygen, more preferably zirconia, and vanadium oxide supported on titania, the vanadium oxide more preferably being one or more of vanadium(V) oxide and vanadium(IV) oxide, the vanadium oxide optionally comprising one or more of tungsten, iron and antimony, and the titania optionally containing one or more of tungsten and silicon; (ii) A second catalyst having an inlet end and an outlet end, comprising a coating disposed on a substrate, the coating comprising, preferably consisting of, a mixture of platinum and palladium supported on an oxide material comprising a mixture of zirconia and alumina (the mass ratio of platinum to palladium, calculated as Pt:Pd, is preferably in the range of 5:1 to 15:1, more preferably in the range of 8:1 to 12:1, more preferably in the range of 9:1 to 11:1), a zeolite material having a Type CHA framework structure and containing copper, and a metal oxide binder material, preferably as defined herein. Equipped with the first catalyst according to (i) is a first catalyst of the exhaust gas treatment system downstream of an upstream end of the exhaust gas treatment system, and an inlet end of the first catalyst is located upstream of an outlet end of the first catalyst; The present invention preferably relates to an exhaust gas treatment system in which the second catalyst according to (ii) is located downstream of the first catalyst according to (i), and the inlet end of the second catalyst is arranged upstream of the outlet end of the second catalyst.

[0166] More preferably, 95 to 100% by weight, more preferably 98 to 100% by weight, more preferably 99 to 100% by weight, more preferably 99.5 to 100% by weight of the coating of the first catalyst comprises, or preferably consists of, palladium supported on an oxide material consisting of zirconia, and vanadium oxide supported on titania, the vanadium oxide being more preferably one or more of vanadium(V) oxide and vanadium(IV) oxide, the vanadium oxide optionally containing one or more of tungsten, iron, and antimony, and the titania optionally containing one or more of tungsten and silicon. 95 to 100% by weight, preferably 98 to 100% by weight, more preferably 99 to 100% by weight, more preferably 99.5 to 100% by weight of the coating of the second catalyst comprises a mixture of platinum and palladium supported on an oxide material comprising a mixture of zirconia and alumina (the mass ratio of platinum to palladium, calculated as Pt:Pd, is preferably in the range of 5:1 to 15:1, more preferably in the range of 8:1 to 12:1, more preferably in the range of 9:1 to 11:1), a zeolite material having a type CHA framework structure and containing copper, and preferably a metal oxide binder as defined in the present invention.

[0167] Alternatively, the second catalyst coating comprises, preferably consists of, platinum supported on an oxide material comprising a mixture of zirconia and alumina, a zeolite material having a CHA type framework structure and comprising copper, and a metal oxide binder material preferably as defined in the present invention. More preferably, 95 to 100% by weight, preferably 98 to 100% by weight, more preferably 99 to 100% by weight, more preferably 99.5 to 100% by weight of the second catalyst coating comprises platinum supported on an oxide material comprising a mixture of zirconia and alumina, a zeolite material having a CHA type framework structure and comprising copper, and a metal oxide binder material preferably as defined in the present invention.

[0168] According to the present invention, it is preferred that the coating of the first catalyst comprises, preferably consists of, palladium supported on an oxide material comprising zirconium, preferably consisting of zirconia, and a zeolitic material having a type CHA framework structure and comprising copper, and a metal oxide binder preferably as defined in the present invention, and that the coating of the second catalyst comprises, preferably consists of, platinum supported on an oxide material comprising a mixture of zirconia and alumina, a zeolitic material having a type CHA framework structure and comprising copper, and a metal oxide binder preferably as defined in the present invention.

[0169] Accordingly, the present invention provides an exhaust gas treatment system for treating an exhaust gas stream exiting a diesel engine, said exhaust gas treatment system having an upstream end for introducing said exhaust gas stream into said exhaust gas treatment system, said exhaust gas treatment system comprising: (i) a first catalyst having an inlet end and an outlet end and comprising a coating disposed on a substrate, the coating comprising, preferably consisting of, palladium supported on an oxide material comprising zirconium, preferably consisting of zirconium and oxygen, more preferably consisting of zirconia, a zeolite material having a type CHA framework structure and comprising copper, and a metal oxide binder material preferably as defined in the present invention; (ii) a second catalyst having an inlet end and an outlet end and comprising a coating disposed on a substrate, the coating comprising, preferably consisting of, platinum supported on an oxide material comprising a mixture of zirconia and alumina, a zeolite material having a Type CHA framework structure and comprising copper, and a metal oxide binder material preferably as defined in the present invention. Equipped with the first catalyst according to (i) is a first catalyst of the exhaust gas treatment system downstream of an upstream end of the exhaust gas treatment system, and an inlet end of the first catalyst is located upstream of an outlet end of the first catalyst; The present invention preferably relates to an exhaust gas treatment system in which the second catalyst according to (ii) is located downstream of the first catalyst according to (i), and the inlet end of the second catalyst is arranged upstream of the outlet end of the second catalyst.

[0170] More preferably 95 to 100% by weight, more preferably 98 to 100% by weight, more preferably 99 to 100% by weight, more preferably 99.5 to 100% by weight of the coating of the first catalyst comprises palladium supported on an oxide material consisting of zirconia, a zeolite material having a framework structure type CHA and comprising copper, and a metal oxide binder preferably as defined in the present invention, and 95 to 100% by weight, preferably 98 to 100% by weight, more preferably 99 to 100% by weight, more preferably 99.5 to 100% by weight of the coating of the second catalyst comprises platinum supported on an oxide material comprising a mixture of zirconia and alumina, a zeolite material having a framework structure type CHA and comprising copper, and a metal oxide binder preferably as defined in the present invention.

[0171] Alternatively, the first catalyst coating comprises, preferably consists of, palladium supported on an oxide material comprising zirconium, preferably zirconium and oxygen, more preferably zirconia, and vanadium oxide supported on titania, the vanadium oxide more preferably being one or more of vanadium(V) oxide and vanadium(IV) oxide, the vanadium oxide optionally containing one or more of tungsten, iron and antimony, the titania optionally containing tungsten and silicon, and the second catalyst coating comprises, preferably consists of, platinum supported on an oxide material comprising a mixture of zirconia and alumina and a zeolitic material having a type CHA framework structure and containing copper, and a metal oxide binder, preferably as defined in the present invention.

[0172] Accordingly, the present invention provides an exhaust gas treatment system for treating an exhaust gas stream exiting a diesel engine, said exhaust gas treatment system having an upstream end for introducing said exhaust gas stream into said exhaust gas treatment system, said exhaust gas treatment system comprising: (i) A first catalyst having an inlet end and an outlet end, comprising a coating disposed on a substrate, the coating comprising, preferably consisting of, palladium supported on an oxide material comprising zirconium, preferably zirconium and oxygen, more preferably zirconia, and vanadium oxide supported on titania, the vanadium oxide more preferably being one or more of vanadium(V) oxide and vanadium(IV) oxide, the vanadium oxide optionally comprising one or more of tungsten, iron and antimony, and the titania optionally containing tungsten and silicon. (ii) a second catalyst having an inlet end and an outlet end and comprising a coating disposed on a substrate, the coating comprising, preferably consisting of, platinum supported on an oxide material comprising a mixture of zirconia and alumina, a zeolite material having a Type CHA framework structure and comprising copper, and a metal oxide binder material preferably as defined in the present invention. Equipped with the first catalyst according to (i) is a first catalyst of the exhaust gas treatment system downstream of an upstream end of the exhaust gas treatment system, and an inlet end of the first catalyst is located upstream of an outlet end of the first catalyst; The present invention further relates to an exhaust gas treatment system in which a second catalyst according to (ii) is located downstream of the first catalyst according to (i), and the inlet end of the second catalyst is disposed upstream of the outlet end of the second catalyst.

[0173] More preferably, 95 to 100% by weight, more preferably 98 to 100% by weight, more preferably 99 to 100% by weight, more preferably 99.5 to 100% by weight of the coating of the first catalyst comprises palladium supported on an oxide material consisting of zirconia and vanadium oxide supported on titania, the vanadium oxide more preferably being one or more of vanadium(V) oxide and vanadium(IV) oxide, the vanadium oxide optionally containing one or more of tungsten, iron and antimony; and 95 to 100% by weight, preferably 98 to 100% by weight, more preferably 99 to 100% by weight, more preferably 99.5 to 100% by weight of the coating of the second catalyst comprises platinum supported on an oxide material comprising a mixture of zirconia and alumina, a zeolite material having a type CHA framework structure and containing copper, and a metal oxide binder material preferably as defined in the present invention.

[0174] According to the invention, it is preferred that the substrate of the first catalyst comprises, preferably consists of, cordierite, and that the substrate of the second catalyst comprises, preferably consists of cordierite.

[0175] Preferably, the substrate for the first catalyst, the substrate on which the coating of the first catalyst is disposed, is a first substrate, and the substrate for the second catalyst, the substrate on which the coating of the second catalyst is disposed, is a second substrate, and the first substrate and the second substrate are different from each other.

[0176] There are no particular limitations regarding the size (length and width) of the substrates of the first catalyst and the second catalyst, provided that each substrate is suitable for the intended use of the first catalyst and the second catalyst, respectively, included in the exhaust gas treatment system of the present invention.

[0177] Preferably, the substrate of the first catalyst has a substrate length in the range of 2.54 to 25.4 cm (1 to 10 inches), preferably in the range of 5.08 to 20.32 cm (2 to 8 inches), more preferably in the range of 10.16 to 19.05 cm (4 to 7.5 inches), more preferably in the range of 12.7 to 17.78 cm (5 to 7 inches).

[0178] Preferably, the substrate for the second catalyst has a substrate length in the range of 2.54 to 25.4 cm (1 to 10 inches), more preferably in the range of 3.81 to 17.78 cm (1.5 to 7 inches), more preferably in the range of 5.08 to 12.7 cm (2 to 5 inches), and more preferably in the range of 5.08 to 10.16 cm (2 to 4 inches). More preferably, the substrate for the first catalyst has a substrate length in the range of 12.7 to 17.78 cm (5 to 7 inches), and the substrate for the second catalyst has a substrate length in the range of 5.08 to 10.16 cm (2 to 4 inches).

[0179] Preferably, the length of the first substrate is longer than the length of the second substrate, and the ratio of the length of the first substrate to the length of the second substrate is preferably in the range of 1.1:1 to 4:1, more preferably in the range of 1.5:1 to 3.5:1, more preferably in the range of 1.9:1 to 2.1:1.

[0180] Preferably, the substrate of the first catalyst has a substrate width in the range of 4 to 17 inches, preferably in the range of 7 to 15 inches, more preferably in the range of 8 to 14 inches, more preferably in the range of 9 to 13 inches, more preferably in the range of 9 to 11 inches.

[0181] Preferably, the substrate of the second catalyst has a substrate width in the range of 4 to 17 inches, more preferably in the range of 7 to 15 inches, more preferably in the range of 8 to 14 inches, more preferably in the range of 9 to 13 inches, more preferably in the range of 9 to 11 inches. More preferably, the substrate of the first catalyst has a substrate width in the range of 22.86 to 33.02 cm (9 to 13 inches), more preferably in the range of 22.86 to 33.02 cm (9 to 13 inches), more preferably in the range of 22.86 to 27.94 cm (9 to 11 inches), and the substrate of the second catalyst has a substrate width in the range of 22.86 to 33.02 cm (9 to 13 inches), more preferably in the range of 22.86 to 27.94 cm (9 to 11 inches).

[0182] According to the present invention, it may be preferred that a first catalyst substrate, the substrate having a first catalyst coating disposed thereon, and a second catalyst substrate, the substrate having a second catalyst coating disposed thereon, together form a single substrate, the single substrate having an inlet end and an outlet end, the inlet end being located upstream of the outlet end, a first catalyst coating disposed on the single substrate from the inlet end to the outlet end of the single substrate, a second catalyst coating disposed on the single substrate from the outlet end to the inlet end of the single substrate, the first catalyst coating covering 25-75% of the substrate length, and the second catalyst coating covering 25-75% of the substrate length. More preferably, the first catalyst coating covers 25-70%, preferably 35-65%, more preferably 45-55% of the substrate length, and the second catalyst coating covers 25-70%, preferably 35-65%, more preferably 45-55% of the substrate length. Alternatively, more preferably, the first catalyst coating covers 50-75%, preferably 69-75% of the substrate length, and the second catalyst coating covers 25-50%, preferably 25-31% of the substrate length.

[0183] Preferably, the first catalyst coating and the second catalyst coating overlap. Alternatively, it is preferred that there is a gap between the first catalyst coating and the second catalyst coating.

[0184] According to the present invention, the first catalyst preferably does not comprise a further coating. Preferably, the first catalyst consists of a coating disposed on a substrate.

[0185] According to the present invention, the second catalyst preferably does not comprise an additional coating. Preferably, the second catalyst consists of a coating disposed on a substrate.

[0186] More preferably, the first catalyst comprises a coating disposed on a substrate and the second catalyst comprises a coating disposed on a substrate.

[0187] According to the present invention, the exhaust gas treatment system preferably further comprises an injector for injecting a fluid into the exhaust gas stream exiting the diesel engine, said injector being located upstream of the first catalyst and downstream of the upstream end of the exhaust gas treatment system. More preferably, the fluid is a urea solution, more preferably an aqueous urea solution.

[0188] According to the present invention, the exhaust gas treatment system preferably further comprises one or more of a diesel oxidation catalyst, a nitrogen oxide reduction catalyst, and an ammonia oxidation catalyst located downstream of the second catalyst according to (ii).

[0189] Preferably, the exhaust gas treatment system further comprises a diesel oxidation catalyst and a particulate filter, preferably a catalyzed particulate filter, the diesel oxidation catalyst having an inlet end and an outlet end and located downstream of the second catalyst according to (ii), and the particulate filter located downstream of the diesel oxidation catalyst in a direction downstream of the end of the exhaust gas treatment system. More preferably, the outlet end of the second catalyst according to (ii) is in fluid communication with the inlet end of the diesel oxidation catalyst, and no catalyst for treating the exhaust gas stream exiting the second catalyst according to (Ii) is located in the exhaust gas treatment system between the outlet end of the second catalyst according to (Ii) and the inlet end of the diesel oxidation catalyst.

[0190] Alternatively, the exhaust gas treatment system further comprises a particulate filter having an inlet end and an outlet end and located downstream of the second catalyst according to (ii), preferably the outlet end of the second catalyst according to (ii) is in fluid communication with the inlet end of the particulate filter, and preferably no catalyst for treating the exhaust gas flow exiting the second catalyst according to (ii) is located in the exhaust gas treatment system between the outlet end of the second catalyst according to (ii) and the inlet end of the particulate filter. More preferably, the particulate filter is a catalyzed particulate filter.

[0191] The present invention provides a method for simultaneously performing selective catalytic reduction of NOx, oxidation of hydrocarbons, oxidation of nitric oxide, and oxidation of ammonia, comprising the steps of: (1) providing an exhaust gas stream from a diesel engine, the exhaust gas stream comprising one or more of NOx, ammonia, nitric oxide, and hydrocarbons; (2) passing the exhaust gas stream supplied in (1) through the exhaust gas system according to the present invention; The present invention relates to a method comprising:

[0192] The present invention further relates to a catalyst for selective catalytic reduction of NOx and oxidation of hydrocarbons, comprising a coating disposed on a substrate, the coating comprising palladium supported on an oxide material comprising zirconium, and further comprising vanadium oxide and a zeolitic material comprising one or more of copper and iron, wherein 0-2 wt. % of the oxide material consists of ceria and alumina.

[0193] Preferably, the catalyst comprises a hydrocarbon (HC) oxidizing component and a nitrogen (NOx) reducing component.

[0194] Preferably 90 to 100 mass %, more preferably 95 to 100 mass %, more preferably 99 to 100 mass % of the oxide material contained in the coating consists of zirconium and oxygen, preferably zirconia.

[0195] According to the present invention, the coating preferably comprises a zeolite material containing one or more of copper and iron.

[0196] There are no particular limitations regarding the zeolitic material included in the coating of the catalyst of the present invention, provided that said zeolitic material is suitable for the intended use of the catalyst of the present invention. Generally, the zeolite material contained in the coating of the second catalyst is of the type ABW, ACO, AEI, AEL, AEN, AET, AFG, AFI, AFN, AFO, AFR, AFS, AFT, AFV, AFX, AFY, AHT, ANA, APC, APD, AST, ASV, ATN, ATO, ATS, ATT, ATV, AVL, AWO, AWW, BCT, BEA, BEC, BIK, BOF, BOG, BOZ, BPH, BRE, BSV, CAN, CAS, CDO, CFI, CGF, CGS, CHA, -CHI, -CLO, CON, CSV, CZP, DAC, DDR, DFO, DFT, DOH, DON, EAB, EDI, EEI, EMT, EON, EPI, ERI, ESV, ETR, EUO, *-EWT、EZT、FAR、FAU、FER、FRA、GIS、GIU、GME、GON、GOO、HEU、IFO、 IFR、-IFU、IFW、IFY、IHW、IMF、IRN、IRR、-IRY、ISV、ITE、ITG、ITH、 * -ITN、ITR、ITT、-ITV、ITW、IWR、IWS、IWV、IWW、JBW、JNT、JOZ、JRY、JSN、JSR、JST、JSW、KFI、LAU、LEV 、LIO、-LIT、LOS、LOV、LTA、LTF、LTJ、LTL、LTN、MAR、MAZ、MEI、MEL、MEP、MER、MFI、MFS、MON、MOR、MOZ、 * MRE、MSE、MSO、MTF、MTN、MTT、MTW、MVY、MWF、MWW、NAB、NAT、NES、NON、N PO、NPT、NSI、OBW、OFF、OKO、OSI、OSO、OWE、-PAR、PAU、PCR、PHI、PON、PO S、PSI、PUN、RHO、-RON、RRO、RSN、RTE、RTH、RUT、RWR、RWY、SAF、SAO、SAS、SAT、SAV、SBE、SBN、SBS、SBT、SEW、SFE、SFF、SFG、SFH、SFN、SFO、SFS、 * SFV、SFW、SGT、SIV、SOD、SOF、SOS、SSF、 * -SSO、SSY、STF、STI、 *The zeolite material contained in the coating may have a framework structure of STO, STT, STW, -SVR, SVV, SZR, TER, THO, TOL, TON, TSC, TUN, UEI, UFI, UOS, UOV, UOZ, USI, UTL, UWY, VET, VFI, VNI, VSV, WEI, -WEN, YUG, ZON, a mixture of two or more of these, or a mixture of two or more of these. Preferably, the zeolite material contained in the coating has a framework structure of type AEI, GME, CHA, MFI, BEA, FAU, or MOR, or a mixture of two or more of these, more preferably a framework structure of type AEI, CHA, or BEA, or a mixture of two or more of these, more preferably a framework of type CHA or AEI, and more preferably a framework of type CHA. Zeolite materials having a framework structure type CHA include, for example, zeolite SSZ-13 and zeolite SAPO-34, with SSZ-13 being preferred.

[0197] In the context of the present invention, it is preferred that the zeolitic material comprised in the coating of the catalyst, more preferably a zeolitic material having a framework structure type CHA, has an average crystal size, as determined by scanning electron microscopy, of at least 0.5 micrometers, preferably in the range of 0.5 to 1.5 micrometers, more preferably in the range of 0.6 to 1.0 micrometers, more preferably in the range of 0.6 to 0.8 micrometers.

[0198] Preferably, the zeolite material in the coating contains copper, and the amount of copper contained in the zeolite material, calculated as CuO, is preferably in the range of 0.1 to 10.0 mass%, more preferably 2.0 to 7.0 mass%, more preferably 2.5 to 5.5 mass%, more preferably 2.5 to 3.5 mass%, relative to the total mass of the zeolite material. More preferably, the amount of iron contained in the zeolite material, calculated as Fe2O3, is in the range of 0 to 0.01 mass%, preferably 0 to 0.001 mass%, more preferably 0 to 0.0001 mass%, relative to the total mass of the zeolite material.

[0199] Preferably, 95 to 100 mass%, more preferably 98 to 100 mass%, more preferably 99 to 100 mass% of the framework structure of the zeolite material is composed of any one or more of Si, Al, O, H, and P, and the molar ratio of Si to Al in the framework structure, calculated as the molar ratio of SiO2:Al2O3, is preferably in the range of 2:1 to 50:1, more preferably in the range of 4:1 to 45:1, more preferably in the range of 10:1 to 40:1, more preferably in the range of 20:1 to 35:1.

[0200] Preferably, the zeolite material contained in the coating contains iron, and the amount of iron contained in the zeolite material, calculated as Fe2O3, is preferably in the range of 0.1 to 10.0 mass%, more preferably 2.0 to 7.0 mass%, and more preferably 2.5 to 5.5 mass%, relative to the total mass of the zeolite material. Preferably, 95 to 100 mass%, more preferably 98 to 100 mass%, and more preferably 99 to 100 mass% of the framework structure of the zeolite material is composed of any one or more of Si, Al, O, and H and P. The molar ratio of Si to Al in the framework structure, calculated as the molar ratio of SiO2:Al2O3, is preferably in the range of 2:1 to 50:1, more preferably 4:1 to 45:1, more preferably 10:1 to 40:1, and more preferably 20:1 to 35:1.

[0201] Preferably, the catalytic coating further comprises a metal oxide binder, more preferably comprising one or more of zirconia, alumina, titania, silica, and a mixture of oxides comprising two or more of Zr, Al, Ti, and Si, more preferably one or more of alumina and zirconia, more preferably zirconia. More preferably, the catalytic coating has a metal oxide binder content of 1.22 to 12.20 g / L (0.02 to 0.2 g / in). 3 ), more preferably in the range of 4.27 to 9.15 g / L (0.07 to 0.15 g / in 3 ) containing a metal oxide binder at a loading in the range of 0.1 to 1.0 wt.

[0202] According to the present invention, the coating comprises vanadium oxide, preferably one or more of vanadium(V) oxide and vanadium(IV) oxide, and optionally the vanadium oxide comprises one or more of tungsten, iron, and antimony.

[0203] Preferably, the vanadium oxide is supported on an oxide material comprising one or more of titanium, silicon and zirconium, preferably on an oxide material comprising one or more of titanium and silicon, more preferably on an oxide material comprising one or more of titania and silica, more preferably on titania, the titania optionally containing one or more of tungsten and silicon.

[0204] With regard to the substrate of the catalyst of the present invention, it is preferred that said substrate comprises, preferably consists of, a ceramic or metallic material.

[0205] There are no particular limitations regarding the substrate of the catalyst, which may include, and preferably consist of, a ceramic substrate, provided that the substrate is suitable for the intended use of the catalyst of the present invention. Preferably, the ceramic material comprises, and more preferably consists of, one or more of alumina, silica, silicates, aluminosilicates, preferably cordierite or mullite, aluminotitanate, silicon carbide, zirconia, magnesia, preferably spinel and titania, more preferably silicon carbide and cordierite, more preferably cordierite.

[0206] There are no particular limitations regarding the substrate of the catalyst, which may include, and preferably consist of, a metallic substrate, provided that the substrate is suitable for the intended use of the catalyst of the present invention. It is preferred that the metallic material comprises, and more preferably consists of, one or more of iron, chromium, aluminum, and oxygen.

[0207] Preferably, the substrate is a monolith, preferably a honeycomb monolith, more preferably a flow-through honeycomb monolith.

[0208] According to the present invention, the catalyst substrate has a substrate length, and the coating is preferably disposed on 20 to 100% of the substrate length, more preferably 50 to 100%, more preferably 75 to 100%, more preferably 95 to 100%, more preferably 99 to 100%.

[0209] There are no particular limitations regarding the loading of palladium contained in the coating of the catalyst of the present invention, provided that said loading is suitable for the intended use of the catalyst of the present invention. Preferably, the coating has a loading of palladium of 0.035 to 2.82 g / l (1 to 80 g / ft). 3 ), more preferably in the range of 0.53 to 2.12 g / l (15 to 60 g / ft 3 ), more preferably in the range of 0.71 to 1.77 g / l (20 to 50 g / ft 3 ), more preferably in the range of 0.88 to 1.59 g / l (25 to 45 g / ft 3 ), more preferably in the range of 0.88 to 1.24 g / l (25 to 35 g / ft 3 ) containing palladium in a loading range.

[0210] There are no particular limitations regarding the loading of zeolitic material contained in the coating of the catalyst of the present invention, provided that said loading is suitable for the intended use of the catalyst of the present invention. The coating may have a loading of 61.02 to 274.61 g / L (1.0 to 4.5 g / g / in). 3 ), more preferably in the range of 91.54 to 244.10 g / L (1.5 to 4.0 g / in 3 ), more preferably in the range of 122.05 to 183.07 g / L (2.0 to 3.0 g / in 3 ), more preferably in the range of 128.15 to 170.87 g / L (2.1 to 2.8 g / in 3 ), more preferably in the range of 128.15 to 158.66 g / L (2.1 to 2.6 g / in 3It is preferred to include the zeolite material at a loading in the range of 0.1 to 1.0.

[0211] There are no particular limitations regarding the vanadium oxide loading contained in the coating of the catalyst of the present invention, provided that said loading is suitable for the intended use of the catalyst of the present invention. The coating may have a vanadium oxide loading of 122.04 to 366.14 g / L (2.0 to 6.0 g / g / in). 3 ), more preferably in the range of 183.07 to 335.63 g / L (3.0 to 5.5 g / in 3 ), more preferably in the range of 244.1 to 305.12 g / L (4.0 to 5.0 g / in 3 It is preferable that the vanadium oxide is contained in an amount within the range of 1000 to 150 ...

[0212] According to the present invention, it is preferred that 95 to 100% by weight of the coating consists of palladium supported on an oxide material, 99 to 100% by weight of which oxide material consists of zirconium and oxygen, preferably zirconia, a copper-containing zeolite material with a framework structure of type CHA, and a metal oxide binder, preferably as defined in the present invention, more preferably 98 to 100% by weight, more preferably 99 to 100% by weight of the coating.

[0213] Accordingly, the present invention provides a catalyst for the selective catalytic reduction of NOx and oxidation of hydrocarbons, comprising a coating disposed on a substrate, the coating comprising palladium supported on an oxide material comprising zirconium, and further comprising a zeolitic material comprising one or more of copper and iron, and a metal oxide binder material preferably as defined in the present invention; Preferably, the catalyst is 0-2 wt% of the oxide material consists of ceria and alumina, 95-100 wt%, more preferably 98-100 wt%, more preferably 99-100 wt%, more preferably 99.5-100 wt% of the coating consists of palladium supported on an oxide material, and 99-100 wt% of the oxide material consists of zirconium and oxygen, more preferably zirconia, a copper-containing zeolite material having a type CHA framework structure, and a metal oxide bond material preferably as defined in the present invention;

[0214] Alternatively, 95 to 100% by weight of the coating preferably comprises, or consists of, palladium supported on an oxide material (99 to 100% by weight of said oxide material consisting of zirconium and oxygen, preferably zirconia), and vanadium oxide supported on titania, the titania preferably optionally containing one or more of tungsten and silicon.

[0215] Accordingly, the present invention preferably relates to a catalyst for the selective catalytic reduction of NOx and oxidation of hydrocarbons, comprising a coating disposed on a substrate, wherein the coating comprises palladium supported on an oxide material comprising zirconium, and further comprises vanadium oxide, 0 to 2 wt.% of the oxide material consisting of ceria and alumina, and 95 to 100 wt.%, preferably 98 to 100 wt.%, more preferably 99 to 100 wt.%, more preferably 99.5 to 100 wt.% of the coating consists of palladium supported on an oxide material (99 to 100 wt.% of the oxide material consisting of zirconium and oxygen, preferably zirconia), and vanadium oxide supported on titania, wherein the titania optionally contains one or more of tungsten and silicon.

[0216] In accordance with the present invention, the catalyst preferably comprises a selective catalytic reduction (SCR) component and a diesel oxidation component.

[0217] Preferably, 0-0.0035 g / l, preferably 0-0.00035 g / l, more preferably 0-0.000035 g / l of one or more of platinum, iridium, osmium and rhodium is included in the coating, more preferably 0-0.000035 g / l of platinum, iridium, osmium and rhodium is included in the coating.

[0218] Preferably, the coating is platinum-free, preferably platinum- and rhodium-free, more preferably platinum, rhodium, iridium, and osmium-free.

[0219] Preferably, 0 to 2 mass %, more preferably 0 to 1 mass %, more preferably 0 to 0.1 mass % of the palladium-supporting oxide materials contained in the coating consist of ceria, alumina and titania, and more preferably, 0 to 0.1 mass % of the oxide materials contained in the coating consist of ceria, alumina, titania, lanthana and baria.

[0220] Preferably, the palladium-bearing oxide material contained in the coating is free of ceria, alumina and titania, more preferably free of ceria, alumina, titania, lanthana and baria.

[0221] Preferably, the catalyst does not include a further coating. Preferably, the catalyst of the present invention consists of a coating supported on a substrate.

[0222] The present invention provides a method for producing a catalyst, preferably a catalyst according to the invention, comprising the steps of: (a) preparing a first mixture containing an oxide material containing palladium and zirconium, wherein 0 to 2 mass % of the oxide material is made of ceria and alumina, and water; (b) providing a second mixture comprising a solvent and one or more of vanadium oxide and a zeolitic material comprising one or more of copper and iron, wherein the vanadium oxide is preferably supported on an oxide material comprising one or more of titanium, silicon and zirconium, more preferably on an oxide material comprising one or more of titanium and silicon, more preferably on an oxide material comprising one or more of titania and silica, more preferably on titania, and the titania optionally containing one or more of tungsten and silicon; (c) mixing the first mixture obtained in (a) and the second mixture obtained in (b) to obtain a slurry; (d) applying the slurry obtained in (c) to a substrate to obtain a slurry-treated substrate; (e) optionally drying the slurry-treated substrate from (d) to obtain a substrate having a coating disposed thereon; (f) calcining the slurry treated substrate obtained in (d), preferably the dried slurry treated substrate obtained in (e), to obtain a catalyst according to the present invention. The present invention further relates to a method comprising:

[0223] Regarding (a) of the method, there is no particular limitation, provided that (a) provides a first mixture containing oxide materials containing palladium and zirconium, and 0 to 2 mass % of the oxide materials consists of ceria, alumina, and water. Preferably, (a) is a process comprising the following steps: (a.1) mixing an aqueous mixture of a palladium precursor, preferably an aqueous palladium nitrate mixture, with an oxide material comprising zirconium, wherein 0-2 wt.% of the oxide material is comprised of ceria and alumina, to obtain palladium supported on the oxide material; (a.2) calcining the palladium supported on the oxide material obtained in (a.1); (a.3) mixing the calcined palladium supported on the oxide material obtained in (a.2) with a mounting adjuvant, preferably one or more of tartaric acid and monoethanolamine, more preferably tartaric acid and monoethanolamine; Includes.

[0224] More preferably, according to (a.1), an aqueous mixture of palladium precursor, preferably an aqueous palladium nitrate mixture, is added dropwise to the oxide material.

[0225] Preferably, according to (a.2), the palladium supported on the oxide material is fired in a gas atmosphere having a temperature in the range of 490 to 690°C, preferably in the range of 540 to 640°C, more preferably in the range of 570 to 610°C.

[0226] Preferably, according to (a.2), the palladium supported on the oxide material is calcined in a gas atmosphere for a period in the range of 2 to 6 hours, preferably in the range of 3 to 5 hours. More preferably, according to (a.2), the palladium supported on the oxide material is calcined in a gas atmosphere having a temperature in the range of 570 to 610°C for a period in the range of 3 to 5 hours.

[0227] With regard to palladium and oxide materials, reference is made to the respective disclosures regarding the coating of the catalyst according to the invention.

[0228] There are no particular limitations regarding (b) of the method, provided that (b) results in an oxide material comprising one or more of titanium, silicon and zirconium, more preferably an oxide material comprising one or more of titanium and silicon, more preferably an oxide material comprising one or more of titania and silica, more preferably vanadium oxide preferably supported on titania, the titania optionally containing one or more of tungsten and silicon, and one or more of zeolitic materials comprising one or more of copper and iron, and a solvent. Preferably, (b) is a process comprising the steps of: (b.1) mixing a mixture of zirconium acetate sources with a zeolitic material having a type CHA framework structure and containing one or more of copper and iron, or producing a vanadium oxalate solution, more preferably adding an oxide material together with a dispersing agent; (b.2) milling the mixture obtained in (b.1) to a particle size Dv90 in the range of 1 to 15 micrometers, preferably in the range of 2 to 10 micrometers, more preferably in the range of 3.5 to 6 micrometers, as determined by Reference Example 1. Includes.

[0229] With regard to the zeolitic material and vanadium oxide, reference is made to the respective disclosures regarding the coating of the catalyst according to the invention.

[0230] Preferably, disposing the slurry on the substrate in (d) having a substrate length includes a step of disposing the slurry on 20 to 100% of the substrate length, more preferably 50 to 100%, more preferably 75 to 100%, more preferably 95 to 100%, more preferably 99 to 100%.

[0231] Preferably, according to (e), the slurry-treated substrate is dried in a gas atmosphere having a temperature in the range of 90 to 200°C, more preferably in the range of 110 to 180°C, more preferably in the range of 120 to 160°C, and more preferably the slurry-treated substrate is dried in the gas atmosphere for a period in the range of 5 to 300 minutes, more preferably in the range of 10 to 120 minutes, more preferably in the range of 20 to 60 minutes.

[0232] Preferably, according to (e), the slurry-treated substrate is dried in a gas atmosphere having a temperature in the range of 90 to 200°C, more preferably in the range of 100 to 150°C, more preferably in the range of 110 to 130°C, preferably for a period of preferably in the range of 5 to 300 minutes, more preferably in the range of 5 to 60 minutes, more preferably in the range of 7 to 20 minutes, and further dried in a gas atmosphere preferably having a temperature in the range of 90 to 200°C, more preferably in the range of 140 to 180°C, more preferably in the range of 150 to 170°C, preferably for a period of preferably in the range of 5 to 300 minutes, more preferably in the range of 10 to 80 minutes, more preferably in the range of 20 to 40 minutes.

[0233] Preferably, according to (f), the slurry-treated substrate obtained in (d), preferably the dried slurry-treated substrate obtained in (e), is fired in a gas atmosphere having a temperature in the range of 300 to 600°C, more preferably in the range of 400 to 500°C, more preferably in the range of 425 to 475°C.

[0234] Preferably, according to (f), the slurry-treated substrate obtained in (d), more preferably the dried slurry-treated substrate obtained in (e), is fired in a gas atmosphere for a period of 5 to 120 minutes, more preferably 10 to 90 minutes, more preferably 15 to 50 minutes, more preferably 20 to 40 minutes. More preferably, according to (f), the slurry-treated substrate obtained in (d), more preferably the dried slurry-treated substrate obtained in (e), is fired in a gas atmosphere having a temperature in the range of 425 to 475°C for a period of 20 to 40 minutes.

[0235] Preferably, the method comprises the steps of: (a) preparing a first mixture containing an oxide material containing palladium and zirconium, wherein 0 to 2 mass % of the oxide material is made of ceria and alumina, and water; (b) providing a second mixture comprising a solvent and one or more of vanadium oxide and a zeolitic material comprising one or more of copper and iron, wherein the vanadium oxide is preferably supported on an oxide material comprising one or more of titanium, silicon and zirconium, more preferably on an oxide material comprising one or more of titanium and silicon, more preferably on an oxide material comprising one or more of titania and silica, more preferably on titania, and the titania optionally containing one or more of tungsten and silicon; (c) mixing the first mixture obtained in (a) and the second mixture obtained in (b) to obtain a slurry; (d) applying the slurry obtained in (c) to a substrate to obtain a slurry-treated substrate; (e) drying the slurry-treated substrate from (d) to obtain a substrate having a coating disposed thereon; (f) calcining the dried slurry-treated substrate obtained in (e) to obtain the catalyst according to the present invention. It consists of:

[0236] The present invention relates to a catalyst, preferably a catalyst according to the invention, a process according to the invention, preferably (a) preparing a first mixture containing an oxide material containing palladium and zirconium, wherein 0 to 2 mass % of the oxide material is made of ceria and alumina, and water; (b) providing a second mixture comprising a solvent and one or more of vanadium oxide and a zeolitic material comprising one or more of copper and iron, wherein the vanadium oxide is preferably supported on an oxide material comprising one or more of titanium, silicon and zirconium, more preferably on an oxide material comprising one or more of titanium and silicon, more preferably on an oxide material comprising one or more of titania and silica, more preferably on titania, and the titania optionally containing one or more of tungsten and silicon; (c) mixing the first mixture obtained in (a) and the second mixture obtained in (b) to obtain a slurry; (d) applying the slurry obtained in (c) to a substrate to obtain a slurry-treated substrate; (e) drying the slurry-treated substrate from (d) to obtain a substrate having a coating disposed thereon; (f) calcining the dried slurry-treated substrate obtained in (e) to obtain the catalyst according to the present invention. It further relates to a catalyst obtainable or obtained by a process comprising:

[0237] The present invention further relates to the use of a catalyst according to the present invention as a first catalyst in an exhaust gas treatment system for treating an exhaust gas stream leaving a diesel engine, preferably in an exhaust gas treatment system according to the present invention.

[0238] The present invention further relates to a method of using the catalyst according to the invention for simultaneous selective catalytic reduction of NOx and oxidation of hydrocarbons. Preferably, the catalyst is used in combination with one or more of a diesel oxidation catalyst, a nitrogen oxide reduction catalyst and an ammonia oxidation catalyst, preferably an ammonia oxidation catalyst downstream of the catalyst according to the invention, more preferably an ammonia oxidation catalyst downstream of the catalyst according to the invention and a diesel oxidation catalyst downstream of the ammonia oxidation catalyst.

[0239] The present invention provides a method for simultaneous selective catalytic reduction of NOx and oxidation of hydrocarbons, wherein NOx and hydrocarbons are contained in an exhaust gas stream, comprising: (1) providing an exhaust gas stream, preferably from a diesel engine; (2) passing the exhaust gas stream supplied in (1) through a catalyst according to the present invention; The present invention further relates to a method comprising:

[0240] The present invention provides a method for producing a catalyst, preferably a first catalyst, included in an exhaust gas treatment system according to the present invention, comprising the steps of: (A) providing a first mixture containing palladium, an oxide material containing zirconium, and water; (B) providing a second mixture comprising a solvent and one or more of vanadium oxide and a zeolitic material comprising one or more of copper and iron, wherein the vanadium oxide is preferably supported on an oxide material comprising one or more of titanium, silicon and zirconium, more preferably on an oxide material comprising one or more of titanium and silicon, more preferably on an oxide material comprising one or more of titania and silica, more preferably on titania, wherein the titania optionally contains one or more of tungsten and silicon; (C) mixing the first mixture obtained in (A) and the second mixture obtained in (B) to obtain a slurry; (D) applying the slurry obtained in (C) to a substrate to obtain a slurry-treated substrate; (E) optionally drying the slurry-treated substrate obtained in (D) to obtain a substrate having a coating disposed thereon; (F) calcining the slurry-treated substrate obtained in (D), preferably the dried slurry-treated substrate obtained in (E), to obtain a first catalyst included in the exhaust gas treatment system according to the present invention. The present invention further relates to a method comprising:

[0241] Regarding (A) of the method, there is no particular limitation, provided that (A) produces a first mixture containing an oxide material containing palladium and zirconium, and water. Preferably, (A) is a process comprising the following steps: (A.1) mixing a palladium precursor, preferably an aqueous palladium nitrate mixture, with an oxide material containing zirconium to obtain palladium supported on the oxide material; (A.2) calcining the palladium supported on the oxide material obtained in (A.1); (A.3) mixing the calcined palladium supported on the oxide material obtained in (A.2) with a mounting adjuvant, preferably one or more of tartaric acid and monoethanolamine, more preferably tartaric acid and monoethanolamine; Includes.

[0242] Preferably, according to (A.1), an aqueous mixture of palladium precursors, preferably an aqueous palladium nitrate mixture, is added dropwise to the oxide material.

[0243] Preferably, according to (A.2), the palladium supported on the oxide material is fired in a gas atmosphere having a temperature in the range of 490 to 690°C, preferably in the range of 540 to 640°C, more preferably in the range of 570 to 610°C.

[0244] Preferably, according to (A.2), the palladium supported on the oxide material is calcined in a gas atmosphere for a period in the range of 2 to 6 hours, preferably in the range of 3 to 5 hours. More preferably, according to (A.2), the palladium supported on the oxide material is calcined in a gas atmosphere having a temperature in the range of 570 to 610°C for a period in the range of 3 to 5 hours.

[0245] With regard to palladium and oxide materials, reference is made to the respective disclosures relating to the coating of the first catalyst contained in the exhaust gas treatment system according to the invention.

[0246] Regarding (B) of the method, there are no particular limitations, provided that (B) results in a second mixture comprising an oxide material comprising one or more of titanium, silicon and zirconium, more preferably an oxide material comprising one or more of titanium and silicon, more preferably an oxide material comprising one or more of titania and silica, more preferably vanadium oxide preferably supported on titania, the titania optionally containing one or more of tungsten and silicon, and one or more of vanadium oxide and a zeolitic material comprising one or more of copper and iron, and a solvent. Preferably, (B) is a process comprising the steps of: (B.1) mixing a mixture of zirconium acetate with a zeolitic material having a type CHA framework structure and containing one or more of copper and iron; or preparing a solution of vanadium oxalate, preferably adding an oxide material, more preferably together with a dispersant; (B.2) Milling the mixture obtained in (b.1) to a particle size Dv90 in the range of 1 to 15 micrometers, preferably in the range of 2 to 10 micrometers, more preferably in the range of 3.5 to 6 micrometers, as determined by Reference Example 1. Includes.

[0247] With regard to the zeolitic material and vanadium oxide, reference is made to the respective disclosures relating to the coating of the first catalyst contained in the exhaust gas treatment system according to the invention.

[0248] Preferably, disposing the slurry on the substrate in (D), which has a substrate length, includes a step of disposing the slurry on 20 to 100% of the substrate length, preferably 50 to 100%, more preferably 75 to 100%, more preferably 95 to 100%, more preferably 99 to 100%.

[0249] Preferably, according to (E), the slurry-treated substrate is dried in a gas atmosphere having a temperature in the range of 90 to 200°C, preferably in the range of 110 to 180°C, more preferably in the range of 120 to 160°C, and more preferably, the slurry-treated substrate is dried in the gas atmosphere for a period in the range of 5 to 300 minutes, more preferably in the range of 10 to 120 minutes, more preferably in the range of 20 to 60 minutes.

[0250] Preferably, according to (E), the slurry-treated substrate is dried in a gas atmosphere having a temperature in the range of 90 to 200°C, preferably in the range of 100 to 150°C, more preferably in the range of 110 to 130°C, for a period of preferably 5 to 300 minutes, more preferably in the range of 5 to 60 minutes, more preferably in the range of 7 to 20 minutes, and further dried in a gas atmosphere having a temperature in the range of 90 to 200°C, preferably in the range of 140 to 180°C, more preferably in the range of 150 to 170°C, for a period of preferably 5 to 300 minutes, more preferably in the range of 10 to 80 minutes, more preferably in the range of 20 to 40 minutes.

[0251] Preferably, according to (F), the slurry-treated substrate obtained in (D), preferably the dried slurry-treated substrate obtained in (E), is fired in a gas atmosphere having a temperature in the range of 300 to 600°C, preferably in the range of 400 to 500°C, more preferably in the range of 425 to 475°C.

[0252] Preferably, according to (F), the slurry-treated substrate obtained in (D), preferably the dried slurry-treated substrate obtained in (E), is fired in a gas atmosphere for a period of 5 to 120 minutes, preferably 10 to 90 minutes, more preferably 15 to 50 minutes, more preferably 20 to 40 minutes. More preferably, according to (F), the slurry-treated substrate obtained in (D), preferably the dried slurry-treated substrate obtained in (E), is fired in a gas atmosphere having a temperature in the range of 425 to 475°C for a period of 20 to 40 minutes.

[0253] Preferably, the method comprises the steps of: (A) providing a first mixture containing palladium, an oxide material containing zirconium, and water; (B) providing a second mixture comprising a solvent and one or more of vanadium oxide and a zeolitic material comprising one or more of copper and iron, wherein the vanadium oxide is preferably supported on an oxide material comprising one or more of titanium, silicon and zirconium, more preferably on an oxide material comprising one or more of titanium and silicon, more preferably on an oxide material comprising one or more of titania and zirconia, more preferably on titania, wherein the titania optionally contains one or more of tungsten and silicon; (C) mixing the first mixture obtained in (A) and the second mixture obtained in (B) to obtain a slurry; (D) applying the slurry obtained in (C) to a substrate to obtain a slurry-treated substrate; (E) drying the slurry-treated substrate obtained in (D) to obtain a substrate having a coating disposed thereon; (F) calcining the slurry-treated dried substrate obtained in (E) to obtain a first catalyst included in the exhaust gas treatment system according to the present invention. It consists of:

[0254] The present invention relates to a catalyst, preferably an exhaust gas treatment system according to the present invention, and a method according to the present invention, preferably (A) providing a first mixture containing palladium, an oxide material containing zirconium, and water; (B) providing a second mixture comprising a solvent and one or more of vanadium oxide and a zeolitic material comprising one or more of copper and iron, wherein the vanadium oxide is preferably supported on an oxide material comprising one or more of titanium, silicon and zirconium, more preferably on an oxide material comprising one or more of titanium and silicon, more preferably on an oxide material comprising one or more of titania and zirconia, more preferably on titania, wherein the titania optionally contains one or more of tungsten and silicon; (C) mixing the first mixture obtained in (A) and the second mixture obtained in (B) to obtain a slurry; (D) applying the slurry obtained in (C) to a substrate to obtain a slurry-treated substrate; (E) drying the slurry-treated substrate obtained in (D) to obtain a substrate having a coating disposed thereon; (F) calcining the slurry-treated dried substrate obtained in (E) to obtain a first catalyst included in the exhaust gas treatment system according to the present invention. The present invention further relates to a first catalyst obtainable or obtained by a process comprising:

[0255] III. Exhaust Gas Treatment System Surprisingly, it has also been found that an exhaust gas treatment system for treating an exhaust gas stream exiting a diesel engine according to the present invention and described below is cost-effective and allows for avoiding engine measures such as increased exhaust gas temperatures while at the same time being resistant to HC poisoning and preventing sulfation in order to maintain sufficient de-NOx to meet environmental requirements.

[0256] Accordingly, the present invention provides an exhaust gas treatment system for treating an exhaust gas stream exiting a diesel engine, said exhaust gas treatment system having an upstream end for introducing said exhaust gas stream into said exhaust gas treatment system, said exhaust gas treatment system comprising: (i) A first catalyst that is a diesel oxidation (DOC) catalyst having an inlet end and an outlet end and consisting of a coating and a substrate, wherein the coating is disposed on an inner wall of the substrate, the substrate having an inlet end, an outlet end, and a substrate length spanning from the inlet end to the outlet end of the substrate and comprising a plurality of passages defined by the inner wall of the substrate, and the coating comprises palladium supported on an oxide material comprising one or more of zirconium, silicon, aluminum, and titanium, and 99 to 100 wt. % of the coating of the first catalyst consists of palladium supported on an oxide material comprising one or more of zirconium, silicon, aluminum, and titanium. (ii) a second catalyst having an inlet end and an outlet end and comprising a coating and a substrate, wherein the coating is disposed on an interior wall of the substrate, the substrate having an inlet end and an outlet end and a substrate length spanning from the inlet end to the outlet end of the substrate, the second catalyst comprising a plurality of passages defined by the interior wall of the substrate, the coating of the second catalyst comprising a zeolitic material including one or more of vanadium oxides and one or more of copper and iron; or a second catalyst having an inlet end and an outlet end, the second catalyst being a catalyst article according to the present invention; Equipped with the first catalyst according to (i) is a first catalyst of the exhaust gas treatment system downstream of an upstream end of the exhaust gas treatment system, and an inlet end of the first catalyst is disposed upstream of an outlet end of the first catalyst; In an exhaust gas treatment system, a second catalyst according to (ii) is located downstream of the first catalyst according to (i), and an inlet end of the second catalyst is disposed upstream of an outlet end of the second catalyst; The present invention further relates to an exhaust gas treatment system in which the outlet end of the first catalyst according to (i) is in fluid communication with the inlet end of the second catalyst according to (ii), and no catalyst for treating the exhaust gas flow exiting the first catalyst is located in the exhaust gas treatment system between the outlet end of the first catalyst according to (i) and the inlet end of the second catalyst according to (ii).

[0257] Preferably, the oxide material included in the first catalyst coating according to (i) comprises, preferably consists of, one or more of zirconium and aluminum. More preferably, the oxide material included in the first catalyst coating according to (i) comprises aluminum, and more preferably 90 to 100%, more preferably 95 to 100%, more preferably 99 to 100%, by weight, of the oxide material included in the first catalyst coating consists of aluminum and oxygen, preferably alumina. Alternatively, more preferably, the oxide material included in the first catalyst coating according to (i) comprises zirconium, and more preferably 90 to 100%, more preferably 95 to 100%, more preferably 99 to 100%, by weight, of the oxide material included in the first catalyst coating consists of zirconium and oxygen, preferably zirconia.

[0258] With regard to the substrate of the first catalyst, it is preferred that said substrate comprises, preferably consists of, a ceramic or metallic material.

[0259] There are no particular limitations regarding the substrate of the first catalyst, which may include, or preferably consist of, a ceramic substrate, provided that the substrate is suitable for the intended use of the first catalyst in the exhaust gas treatment system of the present invention. Preferably, the ceramic material comprises, or more preferably consists of, one or more of alumina, silica, silicates, aluminosilicates, more preferably cordierite or mullite, aluminotitanate, silicon carbide, zirconia, magnesia, preferably spinel and titania, more preferably silicon carbide and cordierite, more preferably one or more of cordierite.

[0260] There are no particular limitations regarding the substrate of the first catalyst, which may comprise, or preferably consist of, a metallic substrate, provided that the substrate is suitable for the intended use of the first catalyst in the exhaust gas treatment system of the present invention. It is preferred that the metallic material comprises, or more preferably consists of, oxygen and one or more of iron, chromium, and aluminum.

[0261] Preferably, the substrate of the first catalyst is a monolith, more preferably a honeycomb monolith, more preferably a flow-through honeycomb monolith.

[0262] According to the present invention, the first catalyst coating is preferably disposed on the inner wall over 20-100% of the substrate length, more preferably over 50-100%, more preferably over 75-100%, more preferably over 95-100%, more preferably over 99-100%. More preferably, the first catalyst coating is disposed on the inner wall over 99.5-100% of the substrate length.

[0263] Generally, there is no limitation regarding the loading of palladium contained in the first catalyst coating according to (i), provided that the loading is suitable for the intended use of the first catalyst in the exhaust gas treatment system of the present invention. Preferably, the first catalyst coating has a loading of 0.18 to 3.53 g / L (5 to 100 g / ft), calculated as elemental palladium. 3 ), more preferably in the range of 0.71 to 2.82 g / l (20 to 80 g / ft 3 ), more preferably in the range of 1.06 to 2.47 g / l (30 to 70 g / ft 3 ), more preferably in the range of 1.24 to 1.94 g / l (35 to 55 g / ft 3 ). More preferably, the first catalyst coating contains palladium at a loading in the range of 1.41 to 1.77 g / L (40 to 50 g / ft 3 ) containing palladium in a loading range.

[0264] Preferably, the loading of the first catalyst coating is 12.20 to 305.11 g / l (0.2 to 5 g / g / in 3 ), more preferably in the range of 30.51 to 183.07 g / L (0.5 to 3 g / in 3 ), more preferably in the range of 42.72 to 122.05 g / L (0.7 to 2 g / in 3 ). More preferably, the loading of the first catalyst coating is in the range of 54.92 to 91.54 g / L (0.9 to 1.5 g / in 3 ) range.

[0265] According to the present invention, it is preferred that 99 to 100% by weight, more preferably 99.5 to 100% by weight, and even more preferably 99.9 to 100% by weight of the first catalyst coating comprises palladium supported on an oxide material, preferably consisting of palladium as described above, and 99 to 100% by weight of the oxide material consists of aluminum and oxygen, preferably alumina. Alternatively, it is preferred that 99 to 100% by weight, more preferably 99.5 to 100% by weight, and even more preferably 99.9 to 100% by weight of the first catalyst coating comprises palladium supported on an oxide material, preferably consisting of palladium as described above, and 99 to 100% by weight of the oxide material consists of zirconium and oxygen, preferably zirconia.

[0266] Preferably, 0-0.0035 g / l, more preferably 0-0.00035 g / l, more preferably 0-0.000035 g / l of one or more of platinum, iridium, osmium and rhodium is included in the first catalyst coating, more preferably 0-0.000035 g / l of platinum, iridium, osmium and rhodium is included in the first catalyst coating.

[0267] Preferably, the coating of the first catalyst is platinum-free, more preferably platinum- and rhodium-free, more preferably platinum, rhodium, iridium and osmium-free, the term "free" as used in this context of the present invention relating to a coating which only contains said element(s) as an unavoidable impurity which may be present in any one of the substances used to produce the coating.

[0268] Preferably, 0 to 2 wt %, more preferably 0 to 1 wt %, more preferably 0 to 0.1 wt % of the oxide material contained in the first catalyst coating consists of ceria and titania, and more preferably 0 to 0.1 wt % of the oxide material contained in the first catalyst coating consists of ceria, titania, lanthana, and baria.

[0269] Preferably, the oxide material included in the coating of the first catalyst is free of ceria, more preferably free of ceria and titania, more preferably free of ceria, titania, lanthana and baria.

[0270] Preferably, 0 to 0.061 g / l of the selective catalytic reduction (SCR) component is included in the first catalyst coating, more preferably 0 to 0.0061 g / l, more preferably 0 to 0.00061 g / l, more preferably 0 g / l of the selective catalytic reduction (SCR) component is included in the first catalyst coating.

[0271] According to the present invention, the second catalytic coating according to (ii) preferably comprises a zeolitic material containing one or more of copper and iron.

[0272] I'm not sure what to do, but I'm sure I'll be able to do it. 、ACO、AEI、AEL、AEN、AET、AFG、AFI、AFN、AFO、AF R, AFS, AFT, AFV, AFX, AFY, AHT, ANA, APC, APD, AST, ASV, ATN, ATO, ATS, ATT, ATV, AVL, AWO, AWW BCT, BEA, BEC, BIK, BOF, BOG, BOZ, BPH, BRE, BSV, CAN, CAS, CDO, CFI, CGF, CGS, CHA, CHI, CL O, CON, CSV, CZP, DAC, DDR, DFO, DFT, DOH, DON, EAB, EDI, EEI, EMT, EON, EPI, ERI, ESV, ETR, EUO * -EWT、EZT、FAR、FAU、FER、FRA、GIS、GIU、GME、GON、GOO、HEU、IFO、 IFR、-IFU、IFW、IFY、IHW、IMF、IRN、IRR、-IRY、ISV、ITE、ITG、ITH、 * -ITN、ITR、ITT、-ITV、ITW、IWR、IWS、IWV、IWW、JBW、JNT、JOZ、JRY、JSN、JSR、JST、JSW、LAKFI、LEV 、LIO、-LIT、LOS、LOV、LTA、LTF、LTJ、LTL、LTN、MAR、MAZ、MEI、MEL、MEP、MER、MFI、MFS、MON、MOR、MOZ * MRE、MSE、MSO、MTF、MTN、MTT、MTW、MVY、MWF、MWW、NAB、NAT、NES、NON、N PO、NPT、NSI、OBW、OFF、OKO、OSI、OSO、OWE、-PAR、PAU、PCR、PHI、PON、PO S、PSI、PUN、RHO、-RON、RRO、RSN、RTE、RTH、RUT、RWR、RWY、SAF、SAO、SA S、SAT、SAV、SBE、SBN、SBS、SBT、SEW、SFE、SFF、SFG、SFH、SFN、SFO、SFS、 * SFV、SFW、SGT、SIV、SOD、SOF、SOS、SSF、 * -SSO、SSY、STF、STI、 *It refers to zeolite materials preferably having STO, STT, STW, -SVR, SVV, SZR, TER, THO, TOL, TON, TSC, TUN, UEI, UFI, UOS, UOV, UOZ, USI, UTL, UWY, VET, VFI, VNI, VSV, WEI, -WEN, YUG, ZON, mixtures of two or more thereof, and mixed types of two or more thereof.

[0273] Preferably, the second catalyst coating comprises a zeolitic material containing one or more of copper and iron, and the zeolitic material comprised in the second catalyst coating has a framework structure of type AEI, GME, CHA, MFI, BEA, FAU, MOR or a mixture of two or more thereof, more preferably a framework structure of type AEI, CHA, BEA or a mixture of two or more thereof, more preferably a framework structure of type CHA or AEI, more preferably a framework structure of type CHA. Zeolitic materials having a framework structure type CHA include, for example, zeolite SSZ-13 and zeolite SAPO-34, with SSZ-13 being preferred.

[0274] In the context of the present invention, it is preferred that the zeolitic material comprised in the coating of the second catalyst, more preferably a zeolitic material having a framework structure type CHA, has an average crystal size of at least 0.5 micrometers, preferably in the range of 0.5 to 1.5 micrometers, more preferably in the range of 0.6 to 1.0 micrometers, more preferably in the range of 0.6 to 0.8 micrometers, as determined by scanning electron microscopy.

[0275] Preferably, the zeolitic material contained in the coating of the second catalyst contains copper, and the amount of copper contained in the zeolitic material, calculated as CuO, is preferably in the range of 0.1 to 10.0% by mass, more preferably in the range of 2.0 to 7.0% by mass, more preferably in the range of 2.5 to 5.5% by mass, more preferably in the range of 2.5 to 3.5% by mass, based on the total mass of the zeolitic material. More preferably, the amount of iron contained in the zeolitic material, calculated as Fe2O3, is in the range of 0 to 0.01% by mass, more preferably in the range of 0 to 0.0 ... based on the total mass of the zeolitic material.

[0276] Preferably, 95 to 100 mass %, more preferably 98 to 100 mass %, more preferably 99 to 100 mass % of the framework structure of the zeolite material consists of one or more of Si, Al, O, and optionally H and P, and the molar ratio of Si to Al in the framework structure, calculated as the molar ratio of SiO2:Al2O3, is preferably in the range of 2:1 to 50:1, more preferably in the range of 4:1 to 45:1, more preferably in the range of 10:1 to 40:1, more preferably in the range of 20:1 to 35:1.

[0277] Preferably, the zeolite material contained in the coating of the second catalyst contains iron, and the amount of iron contained in the zeolite material, calculated as Fe2O3, is preferably in the range of 0.1 to 10.0 mass%, more preferably 1.0 to 7.0 mass%, and more preferably 2.5 to 5.5 mass%, based on the total mass of the zeolite material. Preferably, 95 to 100 mass%, more preferably 98 to 100 mass%, and more preferably 99 to 100 mass% of the framework structure of the zeolite material is composed of any one or more of Si, Al, O, H, and P, and the molar ratio of Si to Al in the framework structure, calculated as SiO2:Al2O3 in moles, is preferably in the range of 2:1 to 50:1, more preferably 4:1 to 45:1, more preferably 10:1 to 40:1, and more preferably 20:1 to 35:1.

[0278] Preferably, the second catalyst coating according to (ii) further comprises a metal oxide binder, the metal oxide binder preferably comprising one or more of zirconia, alumina, titania, silica, and oxide mixtures comprising two or more of Zr, Al, Ti and Si, more preferably one or more of alumina and zirconia, more preferably zirconia. More preferably, the second catalyst coating has a binder content of 1.22 to 12.20 g / l (0.02 to 0.2 g / in 3 ), preferably in the range of 4.88 to 10.98 g / L (0.08 to 0.18 g / in 3 ) containing a metal oxide binder at a loading in the range of 0.1 to 1.0 wt.

[0279] Accordingly, the present invention provides an exhaust gas treatment system for treating an exhaust gas stream exiting a diesel engine, said exhaust gas treatment system having an upstream end for introducing said exhaust gas stream into said exhaust gas treatment system, said exhaust gas treatment system comprising: (i) A first catalyst is a diesel oxidation (DOC) catalyst having an inlet end and an outlet end and comprising a coating and a substrate, the coating being disposed on an interior wall of the substrate, the substrate having an inlet end, an outlet end, and a substrate length spanning from the inlet end to the outlet end of the substrate and comprising a plurality of passages defined by the interior wall of the substrate, the coating comprising palladium supported on an oxide material comprising one or more of zirconium, silicon, aluminum, and titanium, 99-100% by weight of the coating of the first catalyst comprises palladium supported on an oxide material comprising one or more of zirconium and aluminum, and the first catalyst coating has an ion concentration, calculated as elemental palladium, of 0.18-3.53 g / L (5-100 g / ft 3 ), preferably in the range of 0.71 to 2.82 g / l (20 to 80 g / ft 3 ), more preferably in the range of 1.06 to 2.47 g / l (30 to 70 g / ft 3 ), more preferably in the range of 1.24 to 1.94 g / l (35 to 55 g / ft 3), more preferably in the range of 1.41 to 1.77 g / l (40 to 50 g / ft 3 ) a first catalyst containing palladium in a loading range of (ii) a second catalyst having an inlet end and an outlet end and comprising a coating and a substrate, wherein the coating is disposed on an interior wall of the substrate, the substrate having an inlet end and an outlet end and a substrate length extending from the inlet end to the outlet end of the substrate and comprising a plurality of passages defined by the interior wall of the substrate, wherein the coating of the second catalyst comprises a zeolite material having a Type CHA framework structure and comprising copper, and a metal oxide binder material preferably as defined in the present invention, wherein the amount of copper in the zeolite material, calculated as CuO, is preferably in the range of 0.1 to 10.0 mass %, more preferably in the range of 2.0 to 7.0 mass %, more preferably in the range of 2.5 to 5.5 mass %, more preferably in the range of 2.5 to 3.5 mass %, based on the total mass of the zeolite material; or a second catalyst, which is a catalyst article according to the present invention, having an inlet end and an outlet end; Equipped with the first catalyst according to (i) is a first catalyst of the exhaust gas treatment system downstream of an upstream end of the exhaust gas treatment system, and an inlet end of the first catalyst is located upstream of an outlet end of the first catalyst; In an exhaust gas treatment system, a second catalyst according to (ii) is located downstream of the first catalyst according to (i), and an inlet end of the second catalyst is disposed upstream of an outlet end of the second catalyst; The present invention preferably relates to an exhaust gas treatment system in which the outlet end of the first catalyst according to (i) is in fluid communication with the inlet end of the second catalyst according to (ii), and no catalyst for treating the exhaust gas flow exiting the first catalyst is located in the exhaust gas treatment system between the outlet end of the first catalyst according to (i) and the inlet end of the second catalyst according to (ii).

[0280] According to the present invention, the second catalytic coating according to (ii) preferably comprises vanadium oxide. Optionally, the vanadium oxide comprises one or more of tungsten, iron and antimony.

[0281] Preferably, the vanadium oxide is one or more of vanadium(V) oxide and vanadium(IV) oxide, the vanadium oxide optionally containing one or more of tungsten, iron and antimony.

[0282] Preferably, the vanadium oxide is supported on an oxide material comprising one or more of titanium, silicon and zirconium, more preferably on an oxide material comprising one or more of titanium and silicon, more preferably on an oxide material comprising one or more of titania and silica, more preferably on titania, the titania optionally containing one or more of tungsten and silicon. More preferably, the vanadium oxide is one or more of vanadium(V) oxide and vanadium(IV) oxide, and contains antimony, the vanadium oxide being supported on titania.

[0283] Furthermore, the second catalytic coating further comprises a platinum group metal, the platinum group metal being one or more of platinum, palladium, rhodium, iridium and osmium, more preferably one or more of palladium and rhodium, and more preferably the platinum group metal being palladium.

[0284] Preferably, the platinum group metal is supported on an oxide material, and the oxide material included in the second catalyst coating comprises one or more of zirconia, silica, alumina, and titania, more preferably one or more of zirconia and alumina. More preferably, the platinum group metal is supported on zirconia. More preferably, 90 to 100 wt. %, preferably 95 to 100 wt. %, more preferably 99 to 100 wt. % of the oxide material included in the second catalyst coating consists of zirconia.

[0285] According to the present invention, when a zeolite material is included in the second catalyst coating, the second catalyst coating has a zeolite content of 61.02 to 274.61 g / L (1.0 to 4.5 g / g / in 3 ), more preferably in the range of 91.54 to 244.10 g / L (1.5 to 4.0 g / in 3 ), more preferably in the range of 122.05 to 213.58 g / L (2.0 to 3.5 g / in 3 ), more preferably in the range of 128.15 to 183.07 g / L (2.1 to 3 g / in 3 Preferably, the second catalyst coating comprises a zeolite material at a loading in the range of 128.15 to 158.66 g / L (2.1 to 2.6 g / in). More preferably, the second catalyst coating comprises a zeolite material at a loading in the range of 128.15 to 158.66 g / L (2.1 to 2.6 g / in). 3 ) with a loading of zeolite material in the range of 0.1 to 1.0.

[0286] According to the present invention, when vanadium oxide is included in the second catalyst coating, the vanadium oxide is present in an amount of 122 to 335 g / L (2.0 to 5.5 g / in 3 ), more preferably in the range of 240 to 300 g / l (3.9 to 4.9 g / in 3 ), more preferably in the range of 262.4 to 280.7 g / L (4.3 to 4.6 g / in 3 It is preferred that the catalyst is present in a loading range of 0.1 to 1.0.

[0287] Further, when the second catalytic coating contains a platinum group metal, the platinum group metal, calculated as elemental platinum group metal, is present in an amount of 0.035 to 2.82 g / L (1 to 80 g / ft). 3 ), more preferably in the range of 0.53 to 2.12 g / l (15 to 60 g / ft 3 ), more preferably in the range of 0.71 to 1.77 g / l (20 to 50 g / ft 3 It is preferable that the platinum group metal is contained in an amount in the range of 0.88 to 1.59 g / L (25 to 45 g / ft). 3 ), more preferably in the range of 0.88 to 1.24 g / l (25 to 35 g / ft 3) in the second catalyst coating.

[0288] According to a first preferred embodiment of the present invention, the second catalyst coating comprises a copper-containing zeolitic material having a type CHA framework structure, wherein 95-100% by weight, more preferably 98-100% by weight, more preferably 99-100% by weight, more preferably 99.5-100% by weight of the second catalyst coating comprises, preferably consists of, the copper-containing zeolitic material having a type CHA framework structure and a metal oxide binder, preferably as defined in the present invention.

[0289] According to a second preferred embodiment of the present invention, the second catalyst coating comprises a copper-containing zeolitic material having a type CHA framework structure, palladium supported on an oxide material comprising zirconium, and a metal oxide binder, preferably as defined herein, wherein 95 to 100% by weight, more preferably 98 to 100% by weight, more preferably 99 to 100% by weight, even more preferably 99.5 to 100% by weight of the second catalyst coating is comprised of a copper-containing zeolitic material having a type CHA framework structure, palladium supported on an oxide material, 99 to 100% by weight of the oxide material comprising zirconium and oxygen, preferably zirconia, and a metal oxide binder, preferably as defined herein.

[0290] According to a third preferred embodiment of the present invention, the second catalyst coating comprises vanadium oxide supported on an oxide material comprising one or more of titanium, silicon, and zirconium, more preferably one or more of titanium and silicon, more preferably one or more of titania and silica, and more preferably titania, wherein the titania optionally contains one or more of tungsten and silicon. In this case, it is preferred that 95 to 100% by weight, more preferably 98 to 100% by weight, more preferably 99 to 100% by weight, more preferably 99.5 to 100% by weight of the second catalyst coating comprises, or preferably consists of, vanadium oxide supported on an oxide material comprising one or more of titanium, silicon, and zirconium, more preferably one or more of titanium and silicon, more preferably one or more of titania and silica, and more preferably titania, wherein the titania optionally contains one or more of tungsten and silicon.

[0291] According to a fourth preferred embodiment of the present invention, the second catalytic coating comprises an oxide material comprising one or more of titanium, silicon and zirconium, more preferably an oxide material comprising one or more of titanium and silicon, more preferably an oxide material comprising one or more of titania and silicon, more preferably vanadium oxide supported on titania (the titania optionally containing one or more of tungsten and silicon), and palladium supported on an oxide material comprising zirconium. In this case, it is preferred that 95 to 100% by mass of the second catalyst coating, more preferably 98 to 100% by mass, more preferably 99 to 100% by mass, more preferably 99.5 to 100% by mass, comprises, or preferably consists of, an oxide material comprising one or more of titanium, silicon and zirconium, more preferably an oxide material comprising one or more of titanium and silicon, more preferably an oxide material comprising one or more of titania and silica, more preferably vanadium oxide supported on titania (the titania optionally containing one or more of tungsten and silicon), and palladium supported on an oxide material (99 to 100% by mass of the oxide material consists of zirconium and oxygen, preferably zirconia).

[0292] According to the first and third preferred embodiments, the second catalyst coating contains one or more of platinum, palladium, rhodium, iridium, and osmium in an amount of 0 to 0.0035 g / l, more preferably 0 to 0.00035 g / l, more preferably 0 to 0.000035 g / l, and more preferably 0 to 0.0000035 g / l, and more preferably 0 to 0.0000035 g / l. More preferably, the second catalyst coating does not contain platinum, palladium, or rhodium, and more preferably does not contain platinum, palladium, rhodium, iridium, or osmium.

[0293] According to the present invention, one or more of platinum, iridium, osmium and rhodium are contained in the second catalyst coating in an amount of 0-0.0035 g / l, more preferably 0-0.00035 g / l, more preferably 0-0.000035 g / l, more preferably 0-0.0000035 g / l, and more preferably 0-0.0000035 g / l, and more preferably 0-0.0000035 g / l of platinum, iridium, osmium and rhodium are contained in the second catalyst coating.

[0294] Preferably, the second catalytic coating is platinum-free, more preferably platinum- and rhodium-free, more preferably platinum, iridium, osmium, and rhodium-free.

[0295] Furthermore, when the second catalyst coating comprises palladium supported on an oxide material, it is preferred that 0-2 wt %, more preferably 0-1 wt %, more preferably 0-0.1 wt % of the palladium-supported oxide material contained in the second catalyst coating consists of ceria and alumina, and more preferably 0-0.1 wt % of the oxide material contained in the second catalyst coating consists of ceria, alumina, titania, lanthana and baria.

[0296] Preferably, the palladium-supporting oxide material contained in the coating of the second catalyst is free of ceria and alumina, more preferably free of ceria, alumina and titania, more preferably free of ceria, alumina, titania, lanthana and baria.

[0297] According to a second preferred embodiment of the present invention, when the coating of the second catalyst comprises palladium supported on zirconia and a copper-containing zeolitic material having a type CHA framework structure, and preferably a metal oxide binder as defined in the present invention, the zeolitic material and the palladium supported on zirconia, and preferably the binder, are preferably contained in a single coating, which is disposed on at least a portion of the inner wall of the substrate of the second catalyst.

[0298] According to a fifth preferred embodiment of the present invention, the coating of the second catalyst comprises a copper-containing zeolitic material having a type CHA framework structure, and the platinum group metal is one or more of platinum, palladium, rhodium, iridium and osmium, more preferably palladium, supported on an oxide material comprising one or more of zirconia, alumina and titania, preferably one or more of alumina and titania, more preferably one or more of alumina and zirconia, and preferably a metal oxide binder as defined herein; the coating of the second catalyst comprises a top coat comprising the copper-containing zeolitic material having a type CHA framework structure and the metal oxide binder as defined herein, and a bottom coat comprising the platinum group metal supported on the oxide material, the bottom coat being disposed on at least a portion of the inner wall surface of the second catalyst substrate, and the top coat being disposed on the bottom coat.

[0299] According to an alternative fifth preferred aspect of the present invention, the second catalytic coating comprises one or more of vanadium oxides, preferably one or more of vanadium(V) oxide and vanadium(IV) oxide, supported on an oxide material; the platinum group metal is platinum, palladium, rhodium, iridium, and osmium, preferably palladium, supported on an oxide material comprising one or more of zirconia, alumina, and titania, preferably one or more of alumina and zirconia; the second catalytic coating comprises a top coat comprising vanadium oxide supported on the oxide material; and a bottom coat comprising a platinum group metal supported on the oxide material, the bottom coat being disposed on at least a portion of the inner wall surface of the second catalytic substrate; and the top coat being disposed on the bottom coat.

[0300] With respect to the second catalytic bottom coat, it is preferred that the platinum group metal contained in the bottom coat is palladium.

[0301] Preferably, the oxide material contained in the second catalytic bottom coat comprises, preferably consists of, alumina and zirconia.

[0302] Preferably, 60 to 100 mass %, more preferably 70 to 90 mass %, and more preferably 75 to 85 mass % of the oxide material contained in the bottom coat of the second catalyst is made of alumina.

[0303] Preferably, the second catalyst bottom coat has a palladium content of 0.035 to 1.41 g / L (1 to 40 g / ft), calculated as elemental palladium. 3 ), more preferably in the range of 0.18 to 1.06 g / l (5 to 30 g / ft 3 ), more preferably in the range of 0.35 to 0.88 g / l (10 to 25 g / ft 3 ), more preferably in the range of 0.42 to 0.64 g / l (12 to 18 g / ft 3 ) containing palladium in a loading range.

[0304] Preferably, 95 to 100 mass %, more preferably 98 to 100 mass %, more preferably 99 to 100 mass %, more preferably 99.5 to 100 mass % of the bottom coat of the second catalyst comprises palladium supported on an oxide material, preferably consisting of the above-mentioned palladium, and 99.5 to 100 mass % of the oxide material comprises, more preferably consists of, one or more of alumina and zirconia.

[0305] Regarding the second catalyst topcoat, the topcoat has a saturation of 61.02 to 274.61 g / L (1 to 4.5 g / in 3 ), more preferably in the range of 91.54 to 244.10 g / L (1.5 to 4 g / in 3 ), more preferably in the range of 122.05 to 244.10 (2 to 4 g / in 3 ), more preferably in the range of 152.56 to 213.58 g / L (2.5 to 3.5 g / in 3 It is preferred to include the zeolite material at a loading in the range of 0.1 to 1.0.

[0306] Regarding the alternative topcoat of the second catalyst, the topcoat may have a concentration of 91.54 to 335 g / l (1.5 to 5.5 g / in 3 It is preferable that the vanadium oxide is contained in an amount within the range of 1000 to 150 ...

[0307] Preferably, 95 to 100% by weight, more preferably 98 to 100% by weight, more preferably 99 to 100% by weight, more preferably 99.5 to 100% by weight of the bottom coat of the second catalyst consists of palladium supported on an oxide material, 99.5 to 100% by weight of the oxide material comprising, more preferably consisting of, one or more of alumina and zirconia, and 95 to 100% by weight, preferably 98 to 100% by weight, more preferably 99 to 100% by weight, more preferably 99.5 to 100% by weight of the top coat of the second catalyst consists of a copper-containing zeolite material having a type CHA framework structure, and preferably a metal oxide binder as defined in the present invention.

[0308] Alternatively preferred is that 95 to 100% by weight, more preferably 98 to 100% by weight, more preferably 99 to 100% by weight, more preferably 99.5 to 100% by weight of the bottom coat of the second catalyst consists of palladium supported on an oxide material, 99.5 to 100% by weight of said oxide material comprising, more preferably consisting of, one or more of alumina and zirconia, and 95 to 100% by weight, preferably 98 to 100% by weight, more preferably 99 to 100% by weight, more preferably 99.5 to 100% by weight of the top coat of the second catalyst consists of one or more of vanadium oxides, preferably vanadium(V) oxide and vanadium(IV) oxide, supported on an oxide material.

[0309] According to a fifth preferred embodiment, the bottom coat of the second catalyst contains one or more of platinum, iridium, osmium and rhodium in an amount of 0 to 0.0035 g / l, more preferably 0 to 0.00035 g / l, more preferably 0 to 0.000035 g / l, and more preferably 0 to 0.000035 g / l, of platinum, iridium, osmium and rhodium.

[0310] Preferably, the second catalyst bottom coat is free of platinum and rhodium, more preferably free of platinum, rhodium, iridium and osmium.

[0311] According to a fifth preferred embodiment, 0 to 6.10 g / L, more preferably 0 to 0.61 g / L, more preferably 0 to 0.061 g / L, more preferably 0 to 0.0061 g / L of one or more zeolite materials and vanadium oxide are contained in the bottom coat, and more preferably 0 to 0.0061 g / L of zeolite materials and vanadium oxide are contained in the bottom coat of the second catalyst.

[0312] According to a sixth preferred embodiment of the present invention, the second catalyst is a catalyst article according to the present invention, preferably as defined above in paragraph I. More preferably, the first catalyst comprises a single layer or a first (upper or lower) layer and a second (upper or lower) layer.

[0313] According to a seventh preferred embodiment of the present invention, the second catalyst is preferably a first catalyst according to (i) as defined in paragraph II.

[0314] Regarding the second catalyst used in the exhaust gas treatment system of the present invention, the second catalyst is preferably a selective catalytic reduction (SCR) catalyst. Alternatively, the second catalyst may be an ammonia oxidation (AMOX) catalyst.

[0315] According to the present invention, the second catalyst preferably comprises a coating disposed on a substrate.

[0316] With regard to the substrate of the second catalyst, it is preferred that said substrate comprises, and more preferably consists of, a ceramic or metallic material.

[0317] There are no particular limitations regarding the substrate of the second catalyst, which may include, or preferably consist of, a ceramic substrate, provided that the substrate is suitable for the intended use of the second catalyst in the exhaust gas treatment system of the present invention. Preferably, the ceramic material comprises, or more preferably consists of, one or more of alumina, silica, silicates, aluminosilicates, preferably cordierite or mullite, aluminotitanate, silicon carbide, zirconia, magnesia, preferably spinel and titania, more preferably one or more of silicon carbide and cordierite. More preferably, the ceramic substrate comprises, or more preferably consists of, cordierite.

[0318] There are no particular limitations regarding the substrate of the second catalyst, which may include, or preferably consist of, a metallic substrate, provided that the substrate is suitable for the intended use of the second catalyst included in the exhaust gas treatment system of the present invention. It is preferred that the metallic material include, or more preferably consist of, oxygen and one or more of iron, chromium, and aluminum.

[0319] The substrate of the second catalyst is preferably a monolith, preferably a honeycomb monolith, more preferably a flow-through honeycomb monolith.

[0320] Alternatively, the substrate of the second catalyst may be a monolith, preferably a honeycomb monolith, more preferably an extruded honeycomb monolith. More preferably, the extruded honeycomb monolith may comprise, or more preferably consist of, one or more of vanadium oxide, tungsten oxide, titanium oxide, and a zeolite material containing one or more transition metals, preferably one or more of Cu and Fe, with the vanadium oxide optionally comprising one or more of tungsten, iron, and antimony. The extruded honeycomb monolith may further comprise one or more of silicon oxide and aluminum oxide. More preferably, the substrate of the second catalyst may be an extruded honeycomb monolith comprising, or more preferably consisting of, silicon oxide and one or more of vanadium oxide and titanium oxide. It may even be more preferred that the extruded honeycomb monolith be a flow-through extruded honeycomb monolith.

[0321] As a further alternative, the substrate of the second catalyst may preferably be a corrugated monolith, the corrugated monolith comprising, more preferably consisting of, one or more of vanadium oxide, tungsten oxide, titanium oxide, and a zeolite material containing one or more transition metals, preferably one or more of Cu and Fe, and the vanadium oxide optionally comprising one or more of tungsten, iron, and antimony. The corrugated monolith may further contain one or more of silicon oxide and aluminum oxide. More preferably, the substrate of the second catalyst may be a corrugated monolith comprising, more preferably consisting of, silicon oxide and one or more of vanadium oxide and titanium oxide.

[0322] According to the present invention, the substrate of the first catalyst preferably comprises, or more preferably consists of, oxygen and one or more of iron, chromium, and aluminum, and the substrate of the second catalyst preferably comprises, or preferably consists of cordierite. Alternatively, the substrate of the first catalyst preferably comprises, or more preferably consists of cordierite, and the substrate of the second catalyst preferably comprises, or more preferably consists of cordierite.

[0323] There are no particular limitations regarding the size, i.e., length and width, of the substrates of the first and second catalysts, provided that each substrate is suitable for the intended use of the first and second catalysts included in the exhaust gas treatment system of the present invention.

[0324] Preferably, the substrate of the first catalyst has a substrate length in the range of 2.54 to 25.4 cm (1 to 10 inches), more preferably in the range of 3.81 to 20.32 cm (1.5 to 8 inches), more preferably in the range of 5.08 to 17.78 cm (2 to 7 inches), more preferably in the range of 5.08 to 15.24 cm (2 to 6 inches), more preferably in the range of 5.08 to 10.16 cm (2 to 4 inches).

[0325] Preferably, the substrate of the second catalyst has a substrate length in the range of 2.54 to 25.4 cm (1 to 10 inches), more preferably in the range of 3.81 to 20.32 cm (1.5 to 8 inches), more preferably in the range of 5.08 to 17.78 cm (2 to 7 inches), more preferably in the range of 5.08 to 15.24 cm (2 to 6 inches), more preferably in the range of 5.08 to 10.16 cm (2 to 4 inches).

[0326] More preferably, the substrate for the first catalyst has a substrate length in the range of 2 to 4 inches, and the substrate for the second catalyst has a substrate length in the range of 2 to 4 inches.

[0327] Preferably, the substrate of the first catalyst has a substrate width in the range of 4 to 17 inches, more preferably in the range of 7 to 15 inches, more preferably in the range of 8 to 14 inches, more preferably in the range of 9 to 13 inches, more preferably in the range of 9 to 11 inches.

[0328] Preferably, the substrate of the second catalyst has a substrate width in the range of 4 to 17 inches, more preferably in the range of 7 to 15 inches, more preferably in the range of 8 to 14 inches, more preferably in the range of 9 to 13 inches, more preferably in the range of 9 to 11 inches.

[0329] More preferably, the substrate of the first catalyst has a substrate width in the range of 22.86 to 33.02 cm (9 to 13 inches), more preferably in the range of 22.86 to 27.94 cm (9 to 11 inches), and the substrate of the second catalyst has a substrate width in the range of 22.86 to 33.02 cm (9 to 13 inches), more preferably in the range of 22.86 to 27.94 cm (9 to 11 inches).

[0330] According to the present invention, the second catalyst coating is preferably disposed on the inner wall of the second catalyst substrate over 20-100% of the substrate length, more preferably over 50-100%, more preferably over 75-100%, more preferably over 95-100%. More preferably, the second catalyst coating is disposed on the inner wall of the second catalyst substrate over 99-100% of the substrate length.

[0331] Therefore, it is preferred that the first catalyst coating is disposed on the inner wall of the first catalyst substrate over 99-100% of the substrate length, and the second catalyst coating is disposed on the inner wall of the second catalyst substrate over 99-100% of the substrate length.

[0332] According to the present invention, the substrate for the first catalyst, the substrate on which the coating of the first catalyst is disposed, is the first substrate, and the substrate for the second catalyst, the substrate on which the coating of the second catalyst is disposed, is the second substrate, and it is preferred that the first substrate and the second substrate are different from each other.

[0333] Alternatively, the first catalyst substrate, on which the first catalyst coating is disposed, and the second catalyst substrate, on which the second catalyst coating is disposed, together form a single substrate, the single substrate having an inlet end and an outlet end, the inlet end being located upstream of the outlet end, the first catalyst coating being disposed on the single substrate from the inlet end to the outlet end of the single substrate, and the second catalyst coating being disposed on the single substrate from the outlet end to the inlet end of the single substrate, the first catalyst coating covering 5 to 75% of the substrate length and the second catalyst coating covering 25 to 95% of the substrate length, preferably. More preferably, the first catalyst coating covers 20-75%, more preferably 35-65%, more preferably 45-55% of the substrate length, and the second catalyst coating covers 25-80%, more preferably 35-65%, more preferably 45-55% of the substrate length. Alternatively, the first catalyst coating covers 5-60%, more preferably 5-40%, more preferably 8-30%, more preferably 10-25% of the substrate length, and the second catalyst coating covers 40-90%, preferably 50-85%, more preferably 75-85% of the substrate length.

[0334] Preferably, the first catalyst coating and the second catalyst coating overlap. Alternatively, it is preferred that there is a gap between the first catalyst coating and the second catalyst coating.

[0335] According to a fifth preferred embodiment, the second catalyst coating comprises a bottom coat and a top coat, and the bottom coat of the second catalyst coating is disposed on the inner wall of the second catalyst substrate over 20 to 100%, more preferably 50 to 100%, more preferably 75 to 100%, more preferably 95 to 100%, and more preferably 99 to 100% of the substrate length, and the top coat of the second catalyst coating is disposed over 20 to 100%, more preferably 50 to 100%, more preferably 75 to 100%, more preferably 95 to 100%, and more preferably 99 to 100% of the bottom coat substrate length.

[0336] According to the present invention, it is preferred that 99-100% by weight of the coating of the first catalyst consists of palladium supported on an oxide compound consisting of aluminium and oxygen, more preferably alumina, and that the coating of the second catalyst comprises, preferably consists of, a copper-containing zeolitic material having a framework structure of type CHA, and a metal oxide binder, preferably as defined in the present invention.

[0337] Accordingly, the present invention provides an exhaust gas treatment system for treating an exhaust gas stream exiting a diesel engine, said exhaust gas treatment system having an upstream end for introducing said exhaust gas stream into said exhaust gas treatment system, said exhaust gas treatment system comprising: (i) A first catalyst that is a diesel oxidation (DOC) catalyst having an inlet end and an outlet end and comprising a coating and a substrate, wherein the coating is disposed on an inner wall of the substrate, the substrate having an inlet end, an outlet end, and a substrate length spanning from the inlet end to the outlet end of the substrate, the first catalyst comprising a plurality of passages defined by the inner wall of the substrate, the coating comprising palladium supported on an oxide material comprising aluminum, and 99 to 100 wt. % of the coating of the first catalyst comprises palladium supported on an oxide compound comprising aluminum and oxygen, preferably alumina. (ii) A second catalyst having an inlet end and an outlet end and comprising a coating and a substrate, wherein the coating is disposed on an interior wall of the substrate, the substrate having an inlet end and an outlet end and a substrate length extending from the inlet end to the outlet end of the substrate, the coating comprising a plurality of passages defined by the interior wall of the substrate, the coating of the second catalyst comprising, preferably consisting of, a copper-containing zeolite material having a type CHA framework structure, and a metal oxide binder material, preferably as defined herein. Equipped with the first catalyst according to (i) is a first catalyst of the exhaust gas treatment system downstream of an upstream end of the exhaust gas treatment system, and an inlet end of the first catalyst is located upstream of an outlet end of the first catalyst; In an exhaust gas treatment system, a second catalyst according to (ii) is located downstream of the first catalyst according to (i), and an inlet end of the second catalyst is disposed upstream of an outlet end of the second catalyst; The present invention preferably relates to an exhaust gas treatment system in which the outlet end of the first catalyst according to (i) is in fluid communication with the inlet end of the second catalyst according to (ii), and no catalyst for treating the exhaust gas flow exiting the first catalyst is located in the exhaust gas treatment system between the outlet end of the first catalyst according to (i) and the inlet end of the second catalyst according to (ii).

[0338] Preferably 99.5 to 100% by weight, more preferably 99.9 to 100% by weight, of the coating of the first catalyst consists of palladium supported on an oxide compound consisting of aluminum and oxygen, preferably alumina, and 95 to 100% by weight, more preferably 98 to 100% by weight, more preferably 99 to 100% by weight, more preferably 99.5 to 100% by weight of the coating of the second catalyst comprises, preferably consists of, a copper-containing zeolite material having a framework structure of type CHA, and preferably a metal oxide binder as defined in the present invention.

[0339] Alternatively, it is preferred that 99-100% by weight of the first catalytic coating consists of palladium supported on an oxide compound consisting of zirconium and oxygen, more preferably zirconia, and that the second catalytic coating comprises, preferably consists of, a copper-containing zeolitic material having a framework structure of type CHA, and a metal oxide binder, preferably as defined in the present invention.

[0340] Accordingly, the present invention also provides an exhaust gas treatment system for treating an exhaust gas stream exiting a diesel engine, said exhaust gas treatment system having an upstream end for introducing said exhaust gas stream into said exhaust gas treatment system, said exhaust gas treatment system comprising: (i) A first catalyst that is a diesel oxidation (DOC) catalyst having an inlet end and an outlet end and comprising a coating and a substrate, wherein the coating is disposed on an inner wall of the substrate, the substrate having an inlet end, an outlet end, and a substrate length extending from the inlet end to the outlet end of the substrate, the first catalyst comprising a plurality of passages defined by the inner wall of the substrate, the coating comprising palladium supported on an oxide material comprising zirconium, and 99 to 100 weight percent of the coating of the first catalyst comprising palladium supported on an oxide compound comprising zirconium and oxygen, preferably zirconia. (ii) a second catalyst having an inlet end and an outlet end and comprising a coating and a substrate, the substrate having an inlet end and an outlet end and a substrate length spanning the inlet end to the outlet end of the substrate, the coating of the second catalyst comprising, preferably consisting of, a copper-containing zeolite material having a type CHA framework structure, and a metal oxide binder material, preferably as defined herein. Equipped with the first catalyst according to (i) is a first catalyst of the exhaust gas treatment system downstream of an upstream end of the exhaust gas treatment system, and an inlet end of the first catalyst is located upstream of an outlet end of the first catalyst; In an exhaust gas treatment system, a second catalyst according to (ii) is located downstream of the first catalyst according to (i), and an inlet end of the second catalyst is disposed upstream of an outlet end of the second catalyst; The present invention preferably relates to an exhaust gas treatment system in which the outlet end of the first catalyst according to (i) is in fluid communication with the inlet end of the second catalyst according to (ii), and no catalyst for treating the exhaust gas flow exiting the first catalyst is located in the exhaust gas treatment system between the outlet end of the first catalyst according to (i) and the inlet end of the second catalyst according to (ii).

[0341] Preferably 99.5 to 100% by weight, more preferably 99.9 to 100% by weight, of the coating of the first catalyst consists of palladium supported on an oxide compound consisting of zirconia and oxygen, preferably zirconia, and 95 to 100% by weight, more preferably 98 to 100% by weight, more preferably 99 to 100% by weight, more preferably 99.5 to 100% by weight of the coating of the second catalyst comprises, preferably consists of, a copper-containing zeolite material having a framework structure of type CHA, and preferably a metal oxide binder as defined in the present invention.

[0342] Alternatively, it is preferred that 99-100% by weight of the first catalytic coating consists of palladium supported on an oxide compound consisting of aluminium and oxygen, more preferably alumina, and the second catalytic coating comprises, more preferably consists of, vanadium oxide supported on an oxide material comprising one or more of titanium, silicon and zirconium, more preferably on an oxide material comprising one or more of titanium and silicon, more preferably on an oxide material comprising one or more of titania and silica, more preferably on titania, the titania optionally containing one or more of tungsten and silicon.

[0343] Accordingly, the present invention also provides an exhaust gas treatment system for treating an exhaust gas stream exiting a diesel engine, said exhaust gas treatment system having an upstream end for introducing said exhaust gas stream into said exhaust gas treatment system, said exhaust gas treatment system comprising: (i) A first catalyst that is a diesel oxidation (DOC) catalyst having an inlet end and an outlet end and comprising a coating and a substrate, wherein the coating is disposed on an inner wall of the substrate, the substrate having an inlet end, an outlet end, and a substrate length spanning from the inlet end to the outlet end of the substrate and comprising a plurality of passages defined by the inner wall of the substrate, and the coating comprises palladium supported on an oxide material comprising aluminum, and 99 to 100 wt. % of the coating of the first catalyst comprises palladium supported on an oxide compound comprising aluminum and oxygen, preferably alumina. (ii) A second catalyst having an inlet end and an outlet end and comprising a coating and a substrate, the coating being disposed on an interior wall of the substrate, the substrate having an inlet end and an outlet end and a substrate length spanning from the inlet end to the outlet end of the substrate, with a plurality of passages defined by the interior wall of the substrate, the coating of the second catalyst comprising, preferably consisting of, vanadium oxide supported on an oxide material comprising one or more of titanium, silicon, and zirconium, preferably on an oxide material comprising one or more of titanium and silicon, more preferably on an oxide material comprising one or more of titania and silica, more preferably on titania, wherein the titania optionally contains one or more of tungsten and silicon. Equipped with the first catalyst according to (i) is a first catalyst of the exhaust gas treatment system downstream of an upstream end of the exhaust gas treatment system, and an inlet end of the first catalyst is located upstream of an outlet end of the first catalyst; In an exhaust gas treatment system, a second catalyst according to (ii) is located downstream of the first catalyst according to (i), and an inlet end of the second catalyst is disposed upstream of an outlet end of the second catalyst; The present invention preferably relates to an exhaust gas treatment system in which the outlet end of the first catalyst according to (i) is in fluid communication with the inlet end of the second catalyst according to (ii), and no catalyst for treating the exhaust gas flow exiting the first catalyst is located in the exhaust gas treatment system between the outlet end of the first catalyst according to (i) and the inlet end of the second catalyst according to (ii).

[0344] Preferably, 99.5 to 100% by weight, more preferably 99.9 to 100% by weight, of the coating of the first catalyst consists of palladium supported on an oxide compound consisting of aluminium and oxygen, more preferably alumina, and 95 to 100% by weight, more preferably 98 to 100% by weight, more preferably 99 to 100% by weight, more preferably 99.5 to 100% by weight of the coating of the second catalyst comprises, preferably consists of, vanadium oxide supported on an oxide material comprising one or more of titanium, silicon and zirconium, preferably on an oxide material comprising one or more of titanium and silicon, more preferably on an oxide material comprising one or more of titania and silica, more preferably on titania, wherein the titania optionally contains one or more of tungsten and silicon.

[0345] Alternatively, 99-100% by weight of the first catalytic coating preferably consists of palladium supported on an oxide compound comprising zirconium and oxygen, more preferably zirconia, and the second catalytic coating preferably comprises, more preferably consists of, vanadium oxide supported on an oxide material comprising one or more of titanium, silicon and zirconium, more preferably on an oxide material comprising one or more of titanium and silicon, more preferably on an oxide material comprising one or more of titania and silica, more preferably on titania, the titania preferably optionally containing one or more of tungsten and silicon.

[0346] Accordingly, the present invention also provides an exhaust gas treatment system for treating an exhaust gas stream exiting a diesel engine, said exhaust gas treatment system having an upstream end for introducing said exhaust gas stream into said exhaust gas treatment system, said exhaust gas treatment system comprising: (i) A first catalyst that is a diesel oxidation (DOC) catalyst having an inlet end and an outlet end and comprising a coating and a substrate, wherein the coating is disposed on an inner wall of the substrate, the substrate having an inlet end, an outlet end, and a substrate length extending from the inlet end to the outlet end of the substrate and comprising a plurality of passages defined by the inner wall of the substrate, the coating comprising palladium supported on an oxide material comprising zirconium, and 99 to 100 wt. % of the coating of the first catalyst comprises palladium supported on an oxide compound comprising zirconium and oxygen, preferably zirconia. (ii) A second catalyst having an inlet end and an outlet end and comprising a coating and a substrate, wherein the coating is disposed on an interior wall of the substrate, the substrate having an inlet end and an outlet end and a substrate length spanning from the inlet end to the outlet end of the substrate, comprising a plurality of passages defined by the interior wall of the substrate, wherein the coating of the second catalyst comprises, more preferably consists of, vanadium oxide supported on an oxide material comprising one or more of titanium, silicon, and zirconium, preferably on an oxide material comprising one or more of titanium and silicon, more preferably on an oxide material comprising one or more of titania and silica, more preferably on titania, wherein the titania optionally contains one or more of tungsten and silicon. Equipped with the first catalyst according to (i) is a first catalyst of the exhaust gas treatment system downstream of an upstream end of the exhaust gas treatment system, and an inlet end of the first catalyst is located upstream of an outlet end of the first catalyst; In an exhaust gas treatment system, a second catalyst according to (ii) is located downstream of the first catalyst according to (i), and an inlet end of the second catalyst is disposed upstream of an outlet end of the second catalyst; The present invention preferably relates to an exhaust gas treatment system in which the outlet end of the first catalyst according to (i) is in fluid communication with the inlet end of the second catalyst according to (ii), and no catalyst for treating the exhaust gas flow exiting the first catalyst is located in the exhaust gas treatment system between the outlet end of the first catalyst according to (i) and the inlet end of the second catalyst according to (ii).

[0347] Preferably, 99.5 to 100% by weight, more preferably 99.9 to 100% by weight, of the coating of the first catalyst consists of palladium supported on an oxide compound consisting of zirconium and oxygen, preferably zirconia, and 95 to 100% by weight, preferably 98 to 100% by weight, more preferably 99 to 100% by weight, more preferably 99.5 to 100% by weight of the coating of the second catalyst comprises, or preferably consists of, vanadium oxide supported on an oxide material comprising one or more of titanium, silicon and zirconium, preferably on an oxide material comprising one or more of titanium and silicon, more preferably on an oxide material comprising one or more of titania and silica, more preferably on titania, the titania optionally containing one or more of tungsten and silicon.

[0348] According to the present invention, the exhaust gas treatment system further comprises an injector for injecting a fluid into the exhaust gas stream exiting the diesel engine, said injector being preferably located upstream of the first catalyst and downstream of the upstream end of the exhaust gas treatment system. Preferably, the fluid is an aqueous urea solution.

[0349] Alternatively, according to the present invention, the second catalyst according to (ii) included in the exhaust gas treatment system of the present invention has an inlet end and an outlet end and comprises a substrate, the substrate having an inlet end and an outlet end and a substrate length extending from the inlet end to the outlet end of the substrate, and comprising a plurality of passages defined by the inner walls of the substrate, and the substrate of the second catalyst is considered to be an extruded substrate.

[0350] Thus, in accordance with said alternative, the present invention provides an exhaust gas treatment system for treating an exhaust gas stream exiting a diesel engine, said exhaust gas treatment system having an upstream end for introducing said exhaust gas stream into said exhaust gas treatment system, said exhaust gas treatment system comprising: (i) A first catalyst that is a diesel oxidation (DOC) catalyst having an inlet end and an outlet end and consisting of a coating and a substrate, wherein the coating is disposed on an inner wall of the substrate, the substrate having an inlet end, an outlet end, and a substrate length spanning from the inlet end to the outlet end of the substrate and comprising a plurality of passages defined by the inner wall of the substrate, and the coating comprises palladium supported on an oxide material comprising one or more of zirconium, silicon, aluminum, and titanium, and 99 to 100 wt. % of the coating of the first catalyst consists of palladium supported on an oxide material comprising one or more of zirconium, silicon, aluminum, and titanium. (ii) a second catalyst having an inlet end and an outlet end and comprising a substrate, the substrate having an inlet end and an outlet end and a substrate length extending from the inlet end to the outlet end of the substrate and comprising a plurality of passages defined by an interior wall of the substrate, the substrate of the second catalyst being an extruded substrate. Equipped with the first catalyst according to (i) is a first catalyst of the exhaust gas treatment system downstream of an upstream end of the exhaust gas treatment system, and an inlet end of the first catalyst is located upstream of an outlet end of the first catalyst; In an exhaust gas treatment system, a second catalyst according to (ii) is located downstream of the first catalyst according to (i), and an inlet end of the second catalyst is disposed upstream of an outlet end of the second catalyst; The present invention preferably relates to an exhaust gas treatment system in which the outlet end of the first catalyst according to (i) is in fluid communication with the inlet end of the second catalyst according to (ii), and no catalyst for treating the exhaust gas flow exiting the first catalyst is located in the exhaust gas treatment system between the outlet end of the first catalyst according to (i) and the inlet end of the second catalyst according to (ii).

[0351] In this regard, the extruded substrate preferably comprises, more preferably consists of, one or more of vanadium oxide, tungsten oxide, titanium oxide, and a zeolite material containing one or more transition metals, preferably one or more of Cu and Fe, and it is understood that the vanadium oxide may optionally comprise one or more of tungsten, iron, and antimony. The extruded substrate may further contain one or more of silicon oxide and aluminum oxide. More preferably, the substrate of the second catalyst comprises, more preferably consists of, silicon oxide and one or more of vanadium oxide and titanium oxide. It is further preferred that the substrate of the second catalyst is a monolith, preferably a honeycomb monolith, more preferably a flow-through honeycomb monolith. With regard to the above-mentioned second catalyst used in the exhaust gas treatment system of the present invention, the second catalyst is preferably a selective catalytic reduction (SCR) catalyst. More preferably, the second catalyst does not include a coating.

[0352] According to the present invention, as a further alternative, the second catalyst according to (ii) included in the exhaust gas treatment system of the present invention has an inlet end and an outlet end and comprises a substrate, the substrate having an inlet end, an outlet end, and a substrate length extending from the inlet end to the outlet end of the substrate, and comprising a plurality of passages defined by the interior walls of the substrate, and the substrate of the second catalyst is considered to be a corrugated substrate.

[0353] Thus, in accordance with said alternative, the present invention provides an exhaust gas treatment system for treating an exhaust gas stream exiting a diesel engine, said exhaust gas treatment system having an upstream end for introducing said exhaust gas stream into said exhaust gas treatment system, said exhaust gas treatment system comprising: (i) A first catalyst that is a diesel oxidation (DOC) catalyst having an inlet end and an outlet end and consisting of a coating and a substrate, wherein the coating is disposed on an inner wall of the substrate, the substrate having an inlet end, an outlet end, and a substrate length spanning from the inlet end to the outlet end of the substrate and comprising a plurality of passages defined by the inner wall of the substrate, and the coating comprises palladium supported on an oxide material comprising one or more of zirconium, silicon, aluminum, and titanium, and 99 to 100 wt. % of the coating of the first catalyst consists of palladium supported on an oxide material comprising one or more of zirconium, silicon, aluminum, and titanium. (ii) a second catalyst having an inlet end and an outlet end and including a substrate, the substrate having an inlet end and an outlet end, and a substrate length extending from the inlet end to the outlet end of the substrate, the second catalyst including a plurality of passages defined by an interior wall of the substrate, the substrate of the second catalyst being a corrugated substrate; Equipped with the first catalyst according to (i) is a first catalyst of the exhaust gas treatment system downstream of an upstream end of the exhaust gas treatment system, and an inlet end of the first catalyst is disposed upstream of an outlet end of the first catalyst; In an exhaust gas treatment system, a second catalyst according to (ii) is located downstream of the first catalyst according to (i), and an inlet end of the second catalyst is disposed upstream of an outlet end of the second catalyst; The present invention preferably relates to an exhaust gas treatment system in which the outlet end of the first catalyst according to (i) is in fluid communication with the inlet end of the second catalyst according to (ii), and no catalyst for treating the exhaust gas flow exiting the first catalyst is located in the exhaust gas treatment system between the outlet end of the first catalyst according to (i) and the inlet end of the second catalyst according to (ii).

[0354] In this regard, the corrugated substrate preferably comprises, more preferably consists of, one or more of vanadium oxide, tungsten oxide, titanium oxide, and a zeolite material containing one or more transition metals, preferably one or more of Cu and Fe, and it is understood that the vanadium oxide optionally comprises one or more of tungsten, iron, and antimony. The corrugated substrate may further contain one or more of silicon oxide and aluminum oxide. More preferably, the substrate of the second catalyst is a corrugated substrate comprising, more preferably consisting of, silicon oxide and one or more of vanadium oxide and titanium oxide. It is further preferred that the substrate of the second catalyst is a monolith, preferably a corrugated monolith. With regard to the above-mentioned second catalyst used in the exhaust gas treatment system of the present invention, it is preferred that the second catalyst is a selective catalytic reduction (SCR) catalyst. More preferably, the second catalyst does not include a coating.

[0355] According to the present invention, the exhaust gas treatment system preferably further comprises one or more of a diesel oxidation catalyst, a selective catalytic reduction catalyst, an ammonia oxidation catalyst located downstream of the second catalyst according to (ii).

[0356] Preferably, the exhaust gas treatment system of the present invention further comprises an ammonia oxidation catalyst located downstream of the second catalyst according to (ii), the ammonia oxidation catalyst having an inlet end and an outlet end, the outlet end of the second catalyst according to (ii) being in fluid communication with the inlet end of the ammonia oxidation catalyst, and no catalyst for treating exhaust gases exiting the second catalyst is located in the exhaust gas treatment system between the outlet end of the second catalyst according to (ii) and the inlet end of the ammonia oxidation catalyst. More preferably, the ammonia oxidation catalyst comprises a coating disposed on a substrate, the coating comprising a zeolite material including a platinum group metal supported on an oxide material, and one or more of copper and iron.

[0357] More preferably, the zeolitic material comprised in the coating of the ammonia oxidation catalyst has a framework structure of type AEI, GME, CHA, MFI, BEA, FAU, MOR or a mixture of two or more thereof, more preferably a framework structure of type AEI, CHA, BEA or a mixture of two or more thereof, more preferably a framework structure of type CHA or AEI, more preferably a framework structure of type CHA.

[0358] In the context of the present invention, it is preferred that the zeolitic material comprised in the coating of the ammonia oxidation catalyst, more preferably a zeolitic material having a framework structure type CHA, has an average crystallite size, as determined by scanning electron microscopy, of at least 0.5 micrometers, preferably in the range of 0.5 to 1.5 micrometers, more preferably in the range of 0.6 to 1.0 micrometers, more preferably in the range of 0.6 to 0.8 micrometers.

[0359] The zeolite material contained in the ammonia oxidation catalyst coating contains copper, and the amount of copper contained in the zeolite material, calculated as CuO, is preferably in the range of 0.1 to 10.0 mass%, more preferably 2.0 to 7.0 mass%, more preferably 2.5 to 6 mass%, more preferably 2.5 to 5.5 mass%, and even more preferably 2.5 to 3.5 mass%, based on the total mass of the zeolite material. More preferably, the amount of iron contained in the zeolite material, calculated as Fe2O3, is in the range of 0 to 0.01 mass%, more preferably 0 to 0.001 mass%, more preferably 0 to 0.0001 mass%, and even more preferably 0 to 0.0001 mass%, based on the total mass of the zeolite material.

[0360] Preferably, 95 to 100 mass %, more preferably 98 to 100 mass %, more preferably 99 to 100 mass % of the framework structure of the zeolite material is composed of any one or more of Si, Al, O, H, and P, and the molar ratio of Si to Al in the framework structure, calculated as moles of SiO2:Al2O3, is preferably in the range of 2:1 to 50:1, more preferably in the range of 4:1 to 40:1, more preferably in the range of 10:1 to 40:1, more preferably in the range of 20:1 to 35:1.

[0361] The zeolite material contained in the coating of the ammonia oxidation catalyst contains iron, and the amount of iron contained in the zeolite material, calculated as Fe2O3, is preferably in the range of 0.1 to 10.0 mass%, more preferably in the range of 1.0 to 7.0 mass%, more preferably in the range of 2.5 to 5.5 mass%, based on the total mass of the zeolite material. Preferably, 95 to 100 mass%, more preferably 98 to 100 mass%, more preferably 99 to 100 mass% of the framework structure of the zeolite material consists of one or more of Si, Al, O, and optionally H and P, and the molar ratio of Si to Al in the framework structure, calculated as molar SiO2:Al2O3, is preferably in the range of 2:1 to 50:1, more preferably in the range of 4:1 to 40:1, more preferably in the range of 10:1 to 40:1, more preferably in the range of 20:1 to 35:1.

[0362] Preferably, the ammonia oxidation catalyst coating further comprises a metal oxide binder, preferably comprising one or more of zirconia, alumina, titania, silica, and an oxide mixture comprising two or more of Zr, Al, Ti, and Si, more preferably one or more of alumina and zirconia, more preferably zirconia. More preferably, the ammonia oxidation catalyst coating has a metal oxide binder content of 1.22 to 12.20 g / L (0.02 to 0.2 g / in 3 ), preferably in the range of 4.88 to 10.98 g / L (0.08 to 0.18 g / in 3) containing a metal oxide binder at a loading in the range of 0.1 to 1.0 wt.

[0363] With respect to the platinum group metal included in the coating of the ammonia oxidation catalyst, it is preferred that the platinum group metal is one or more of platinum, palladium and rhodium, more preferably one or more of platinum and palladium, more preferably platinum.

[0364] Preferably, the oxide material included in the coating of the ammonia oxidation catalyst comprises, more preferably consists of, one or more of alumina, zirconia, silica, titania and ceria, preferably one or more of alumina, silica and zirconia, more preferably one or more of zirconia and alumina.

[0365] Preferably, 60 to 100 mass %, more preferably 70 to 90 mass %, and more preferably 75 to 85 mass % of the oxide material contained in the coating of the ammonia oxidation catalyst is made of alumina.

[0366] With regard to the substrate of the ammonia oxidation catalyst, it is preferred that the substrate comprises, and more preferably consists of, a ceramic or metallic material.

[0367] There are no particular limitations regarding the substrate of the ammonia oxidation catalyst, which may include, or preferably consist of, a ceramic substrate, provided that the substrate is suitable for the intended use of the ammonia oxidation catalyst in the exhaust gas treatment system of the present invention. Preferably, the ceramic material comprises, or more preferably consists of, one or more of alumina, silica, silicates, aluminosilicates, preferably cordierite or mullite, aluminotitanate, silicon carbide, zirconia, magnesia, preferably spinel and titania, more preferably one or more of silicon carbide and cordierite, more preferably cordierite.

[0368] There are no particular limitations regarding the substrate of the ammonia oxidation catalyst, which may comprise, or preferably consist of, a metallic material, provided that the substrate is suitable for the intended use of the ammonia oxidation catalyst in the exhaust gas treatment system of the present invention. It is preferred that the metallic material preferably comprises, or more preferably consists of, oxygen and one or more of iron, chromium, and aluminum.

[0369] Preferably, the substrate of the ammonia oxidation catalyst is a monolith, more preferably a honeycomb monolith, more preferably a flow-through honeycomb monolith.

[0370] Preferably, the ammonia oxidation catalyst substrate has a substrate length, and the ammonia oxidation catalyst coating is disposed on 20 to 100%, preferably 50 to 100%, more preferably 75 to 100%, more preferably 95 to 100%, more preferably 99 to 100% of the substrate length.

[0371] Preferably, the ammonia oxidation catalyst coating has a platinum group metal content of 0.035 to 0.53 g / l (1 to 15 g / ft). 3 ), more preferably in the range of 0.11 to 0.35 g / l (3 to 10 g / ft 3 ), more preferably in the range of 0.16 to 0.32 g / l (4.5 to 9.0 g / ft 3 ), more preferably in the range of 0.26 to 0.30 g / l (7.5 to 8.5 g / ft 3 ) containing platinum group metals in a loading range.

[0372] Preferably, the ammonia oxidation catalyst coating has a concentration of 30.51 to 335.63 g / L (0.5 to 5.5 g / g / in 3 ), more preferably in the range of 91.54 to 305.12 g / L (1.5 to 5.0 g / in 3 ), more preferably in the range of 122.05 to 244.09 g / L (2.0 to 4.0 g / in 3 ), more preferably in the range of 122.05 to 213.58 g / L (2.0 to 3.5 g / in 3) with a loading of zeolite material in the range of 0.1 to 1.0.

[0373] The ammonia oxidation catalyst coating comprises, or preferably consists of, platinum supported on an oxide material comprising alumina, wherein preferably 75-85 wt% of the oxide material in the ammonia oxidation catalyst coating consists of alumina, a copper-containing zeolite material having a Type CHA framework structure, and a metal oxide binder as defined herein. More preferably, 95-100 wt%, more preferably 98-100 wt%, more preferably 99-100 wt%, and more preferably 99.5-100 wt% of the ammonia oxidation catalyst coating comprises, or preferably consists of platinum supported on an oxide material comprising alumina, wherein preferably 75-85 wt% of the oxide material in the ammonia oxidation catalyst coating consists of alumina, a copper-containing zeolite material having a Type CHA framework structure, and a metal oxide binder as defined herein.

[0374] Accordingly, the present invention provides an exhaust gas treatment system for treating an exhaust gas stream exiting a diesel engine, said exhaust gas treatment system having an upstream end for introducing said exhaust gas stream into said exhaust gas treatment system, said exhaust gas treatment system comprising: (i) A first catalyst that is a diesel oxidation (DOC) catalyst having an inlet end and an outlet end and comprising a coating and a substrate, wherein the coating is disposed on an inner wall of the substrate, the substrate having an inlet end, an outlet end, and a substrate length extending from the inlet end to the outlet end of the substrate and comprising a plurality of passages defined by the inner wall of the substrate, the coating comprising palladium supported on an oxide material comprising zirconium, and 99 to 100 wt. % of the coating of the first catalyst comprises palladium supported on an oxide material comprising zirconium and oxygen, preferably zirconia. (ii) A second catalyst having an inlet end and an outlet end and comprising a coating and a substrate, wherein the coating is disposed on an interior wall of the substrate, the substrate having an inlet end and an outlet end and a substrate length extending from the inlet end to the outlet end of the substrate, the coating comprising a plurality of passages defined by the interior wall of the substrate, and wherein the coating of the second catalyst comprises, preferably consists of, a copper-containing zeolite material having a type CHA framework structure and a metal oxide binder as defined herein. Equipped with (iii) an ammonia oxidation catalyst comprising a coating disposed on a substrate, the coating comprising, preferably consisting of, platinum supported on an oxide material comprising alumina, wherein preferably 75 to 85 wt. % of the oxide material in the coating of the ammonia oxidation catalyst consists of alumina, a copper-containing zeolite material having a Type CHA framework structure, and a metal oxide binder as defined herein; the first catalyst according to (i) is a first catalyst of the exhaust gas treatment system downstream of an upstream end of the exhaust gas treatment system, and an inlet end of the first catalyst is located upstream of an outlet end of the first catalyst; In the exhaust gas treatment system, a second catalyst according to (ii) is located downstream of the first catalyst according to (i), with the inlet end of the second catalyst being located upstream of the outlet end of the second catalyst; an outlet end of the first catalyst according to (i) in fluid communication with an inlet end of the second catalyst according to (ii), and no catalyst for treating the exhaust gas stream exiting the first catalyst is located in the exhaust gas treatment system between the outlet end of the first catalyst according to (i) and the inlet end of the second catalyst according to (ii); The present invention preferably relates to an exhaust gas treatment system in which the ammonia oxidation catalyst according to (iii) is located downstream of the second catalyst according to (ii), the ammonia oxidation catalyst having an inlet end and an outlet end, the outlet end of the second catalyst according to (ii) being in fluid communication with the inlet end of the ammonia oxidation catalyst, and in which no catalyst for treating exhaust gases exiting the second catalyst according to (ii) is located in the exhaust gas treatment system between the outlet end of the second catalyst according to (ii) and the inlet end of the ammonia oxidation catalyst.

[0375] The ammonia oxidation catalyst preferably comprises a coating disposed on a substrate.

[0376] Alternatively, the exhaust gas treatment system of the present invention preferably further comprises a diesel oxidation catalyst located downstream of the second catalyst according to (ii), the diesel oxidation catalyst having an inlet end and an outlet end, the outlet end of the second catalyst according to (ii) being in fluid communication with the inlet end of the diesel oxidation catalyst, and no catalyst for treating exhaust gases exiting the second catalyst according to (ii) is located in the exhaust gas treatment system between the outlet end of the second catalyst according to (ii) and the inlet end of the diesel oxidation catalyst. More preferably, the diesel oxidation catalyst comprises a coating disposed on a substrate, the coating comprising a platinum group metal supported on an oxide material.

[0377] With regard to the platinum group metal included in the coating of said diesel oxidation catalyst, it is preferred that the platinum group metal is one or more of platinum, palladium and rhodium, preferably one or more of platinum and palladium, more preferably platinum.

[0378] Preferably, the oxide material included in the coating of the diesel oxidation catalyst comprises, preferably consists of, one or more of alumina, zirconia, silica, titania and ceria, preferably one or more of alumina, titania and zirconia.

[0379] With regard to the substrate of the diesel oxidation catalyst, it is preferred that the substrate comprises, preferably consists of, a ceramic or metallic material, more preferably cordierite, or comprises, more preferably consists of oxygen and one or more of iron, chromium and aluminum.

[0380] Preferably, the substrate of the diesel oxidation catalyst is a monolith, preferably a honeycomb monolith, more preferably a flow-through honeycomb monolith.

[0381] Preferably, the diesel oxidation catalyst substrate has a substrate length, and the diesel oxidation catalyst coating is disposed on 20-100%, preferably 50-100%, more preferably 75-100%, more preferably 95-100%, more preferably 99-100% of the substrate length.

[0382] Preferably, the diesel oxidation catalyst coating has a platinum group metal content of 0.035 to 1.77 g / l (1 to 50 g / ft), calculated as platinum group metal elements. 3 ), more preferably in the range of 0.07 to 1.41 g / l (2 to 40 g / ft 3 ), more preferably in the range of 0.18 to 1.24 g / l (5 to 35 g / ft 3 ), more preferably in the range of 0.35 to 1.06 g / l (10 to 30 g / ft 3 ) containing platinum group metals in a loading range.

[0383] Accordingly, the present invention provides an exhaust gas treatment system for treating an exhaust gas stream exiting a diesel engine, said exhaust gas treatment system having an upstream end for introducing said exhaust gas stream into said exhaust gas treatment system, said exhaust gas treatment system comprising: (i) A first catalyst that is a diesel oxidation (DOC) catalyst having an inlet end and an outlet end and comprising a coating and a substrate, wherein the coating is disposed on an inner wall of the substrate, the substrate having an inlet end, an outlet end, and a substrate length extending from the inlet end to the outlet end of the substrate, the first catalyst comprising a plurality of passages defined by the inner wall of the substrate, the coating comprising palladium supported on an oxide material comprising zirconium, and 99 to 100 wt. % of the coating of the first catalyst comprises palladium supported on an oxide material comprising zirconium and oxygen, preferably zirconia. (ii) A second catalyst having an inlet end and an outlet end and comprising a coating and a substrate, the coating being disposed on an interior wall of the substrate, the substrate having an inlet end and an outlet end and a substrate length spanning from the inlet end to the outlet end of the substrate, with a plurality of passages defined by the interior wall of the substrate, the coating of the second catalyst comprising, preferably consisting of, vanadium oxide supported on an oxide material comprising one or more of titanium, silicon and zirconium, preferably on an oxide material comprising one or more of titanium and silicon, more preferably on an oxide material comprising one or more of titania and silica, more preferably on titania, wherein the titania optionally contains one or more of tungsten and silicon, and the vanadium oxide optionally contains one or more of tungsten, iron and antimony. (iii) A diesel oxidation catalyst comprising a coating disposed on a substrate, the coating comprising, preferably consisting of, platinum supported on an oxide material comprising one or more of alumina, titania, and zirconia. Equipped with the first catalyst according to (i) is a first catalyst of the exhaust gas treatment system downstream of an upstream end of the exhaust gas treatment system, and an inlet end of the first catalyst is located upstream of an outlet end of the first catalyst; In an exhaust gas treatment system, a second catalyst according to (ii) is located downstream of the first catalyst according to (i), and an inlet end of the second catalyst is disposed upstream of an outlet end of the second catalyst; an outlet end of the first catalyst according to (i) in fluid communication with an inlet end of the second catalyst according to (ii), and no catalyst for treating the exhaust gas stream exiting the first catalyst is located in the exhaust gas treatment system between the outlet end of the first catalyst according to (i) and the inlet end of the second catalyst according to (ii); The present invention preferably relates to an exhaust gas treatment system in which a diesel oxidation catalyst according to (iii) is located downstream of a second catalyst according to (ii), the diesel oxidation catalyst having an inlet end and an outlet end, the outlet end of the second catalyst according to (ii) being in fluid communication with the inlet end of the diesel oxidation catalyst, and no catalyst for treating exhaust gases exiting the second catalyst according to (ii) is located in the exhaust gas treatment system between the outlet end of the second catalyst according to (ii) and the inlet end of the diesel oxidation catalyst.

[0384] Alternatively, according to the present invention, the exhaust gas treatment system preferably further comprises a particulate filter, the particulate filter having an inlet end and an outlet end and located downstream of the second catalyst according to (ii), preferably the outlet end of the second catalyst according to (ii) is in fluid communication with the inlet end of the particulate filter, and no catalyst for treating the exhaust gas flow exiting the second catalyst according to (ii) is located in the exhaust gas treatment system between the outlet end of the second catalyst according to (ii) and the inlet end of the particulate filter. More preferably, the particulate filter is a catalyzed particulate filter.

[0385] The present invention provides a method for simultaneously performing selective catalytic reduction of NOx, oxidation of hydrocarbons, oxidation of nitric oxide, and oxidation of ammonia, comprising the steps of: (1) providing an exhaust gas stream from a diesel engine containing one or more of NOx, ammonia, nitric oxide, and hydrocarbons; (2) passing the exhaust gas stream supplied in (1) through the exhaust gas system according to the present invention; The present invention further relates to a method comprising:

[0386] The present invention provides a method for producing a catalyst, preferably a first catalyst, included in an exhaust gas treatment system according to the present invention, comprising the steps of: (a) providing a slurry comprising an oxide material comprising one or more of palladium, zirconium, and aluminum, and water; (b) applying the slurry obtained in (a) to a substrate to obtain a slurry-treated substrate; (c) optionally drying the slurry-treated substrate from (b) to obtain a substrate having a coating disposed thereon; (d) calcining the slurry-treated substrate obtained in (b), preferably the dried slurry-treated substrate obtained in (c), to obtain a first catalyst included in an exhaust gas treatment system according to the present invention. The present invention further relates to a method comprising:

[0387] Regarding (a) of the method, there is no particular limitation, provided that (a) results in a slurry containing an oxide material containing one or more of palladium, zirconium, and aluminum, and water. Preferably, (a) comprises the following steps: (a.1) mixing an aqueous solution of a palladium precursor, preferably an aqueous solution of palladium nitrate, with an oxide material comprising one or more of zirconium and aluminum to obtain palladium supported on the oxide material; (a.2) calcining the palladium supported on oxide material obtained in (a.1); (a.3) mixing the calcined palladium supported on the oxide material obtained in (a.2) with a mounting adjuvant, preferably one or more of tartaric acid and monoethanolamine, more preferably tartaric acid and monoethanolamine; Includes.

[0388] More preferably, (a) further comprises the step of (a.4) milling the mixture obtained in (a.3) to a particle size Dv90 in the range of 1 to 20 micrometers, preferably in the range of 5 to 15 micrometers, more preferably in the range of 9 to 11 micrometers, as determined according to Reference Example 1.

[0389] Preferably, according to (a.1), an aqueous solution of a palladium precursor, preferably an aqueous solution of palladium nitrate, is added dropwise to the oxide material.

[0390] Preferably, according to (a.2), the palladium supported on the oxide material is fired in a gas atmosphere having a temperature in the range of 490 to 690°C, preferably in the range of 540 to 640°C, more preferably in the range of 570 to 610°C.

[0391] Preferably, according to (a.2), the palladium supported on the oxide material is calcined in a gas atmosphere for a period in the range of 2 to 6 hours, preferably in the range of 3 to 5 hours. More preferably, according to (a.2), the palladium supported on the oxide material is calcined in a gas atmosphere having a temperature in the range of 570 to 610°C for a period in the range of 3 to 5 hours.

[0392] With regard to the oxide material and palladium used according to (a), reference is made to the respective disclosures above with regard to the coating of the first catalyst, in particular that the palladium is preferably present in a slurry containing zirconium or alternatively containing aluminum.

[0393] Furthermore, disposing the slurry on the substrate in (b), which has a substrate length, preferably includes a step of disposing the slurry over 20 to 100% of the substrate length, preferably 50 to 100%, more preferably 75 to 100%, more preferably 95 to 100%, more preferably 99 to 100%.

[0394] According to (c), the slurry-treated substrate is preferably dried in a gas atmosphere having a temperature in the range of 90 to 200°C, more preferably in the range of 110 to 180°C, more preferably in the range of 120 to 160°C, and more preferably the slurry-treated substrate is dried in the gas atmosphere for a period in the range of 5 to 300 minutes, more preferably in the range of 10 to 120 minutes, more preferably in the range of 20 to 60 minutes.

[0395] Furthermore, according to (c), the slurry-treated substrate is preferably dried in a gas atmosphere having a temperature in the range of 90 to 200°C, more preferably in the range of 100 to 150°C, more preferably in the range of 110 to 130°C, for a period in the range of 5 to 300 minutes, more preferably in the range of 5 to 60 minutes, more preferably in the range of 7 to 20 minutes, and further dried in a gas atmosphere having a temperature in the range of 90 to 200°C, preferably in the range of 140 to 180°C, more preferably in the range of 150 to 170°C, for a period in the range of 5 to 300 minutes, more preferably in the range of 10 to 80 minutes, more preferably in the range of 20 to 40 minutes.

[0396] Furthermore, according to (d), the slurry-treated substrate obtained in (b), preferably the dried slurry-treated substrate obtained in (c), is preferably fired in a gas atmosphere having a temperature in the range of 300 to 600°C, preferably in the range of 400 to 500°C, more preferably in the range of 425 to 475°C.

[0397] Preferably, according to (d), the slurry treated substrate obtained in (b), preferably the dried slurry treated substrate obtained in (c), is fired in a gas atmosphere for a period in the range of 5 to 120 minutes, preferably in the range of 10 to 90 minutes, more preferably in the range of 15 to 50 minutes, more preferably in the range of 20 to 40 minutes.

[0398] Preferably, the method comprises the steps of: (a) providing a slurry comprising an oxide material comprising one or more of palladium, zirconium, and aluminum, and water; (b) applying the slurry obtained in (a) to a substrate to obtain a slurry-treated substrate; (c) drying the slurry-treated substrate from (b) to obtain a substrate having a coating disposed thereon; (d) calcining the dried slurry-treated substrate obtained in (c) to obtain a first catalyst included in an exhaust gas treatment system according to the present invention. It consists of:

[0399] IV. Embodiments The present invention is exemplified by the following first set of embodiments, as well as combinations of embodiments derived from the indicated dependencies and forward references. The first set of embodiments may be combined with any one of the following second and third sets of embodiments. Furthermore, it should be noted that in each instance where a range of embodiments is mentioned, for example, in the context of a term such as "the catalytic article (or exhaust gas treatment system) of any one of embodiments 1-4," each embodiment in the range is intended to be expressly disclosed to one of ordinary skill in the art, i.e., the wording of the term should be understood by one of ordinary skill in the art to be synonymous with "the catalytic article (or exhaust gas treatment system) of any one of embodiments 1, 2, 3, and 4."

[0400] 1. A catalyst article comprising a substrate having a catalyst composition disposed thereon, the catalyst composition comprising a platinum group metal (PGM) impregnated in a porous support, and a selective catalytic reduction (SCR) catalyst; The catalyst composition is substantially free of platinum (Pt); Nitrogen oxides (NO x ) and hydrocarbon (HC) reduction, Catalyst article.

[0401] 2. The catalytic article of embodiment 1, wherein the PGM is palladium (Pd), rhodium (Rh) or a combination thereof, preferably palladium or rhodium.

[0402] 3. PGM, calculated as PGM elements, is approximately 0.1 to 100 g / ft 3 , preferably 1 to 50 g / ft 3 , more preferably 1 to 30 g / ft 3 , more preferably 5 g / ft 3 ~about 25g / ft 3 3. The catalyst article of embodiment 1 or 2, having a loading of

[0403] 4. The catalytic article of any one of embodiments 1-3, wherein the porous support comprises a refractory metal oxide material.

[0404] 5. The catalytic article of embodiment 4, wherein the refractory metal oxide material comprises ceria, zirconia, yttria, lanthana, neodymia, praseodymia, or a combination thereof.

[0405] 6. The catalytic article of embodiment 4 or 5, wherein the refractory metal oxide material comprises a ceria-zirconia composite.

[0406] 7. The catalyst article of embodiment 6, wherein the ceria and zirconia of the ceria-zirconia composite are each present in an amount ranging from about 5 to about 75 weight percent, based on the total weight of the ceria-zirconia composite.

[0407] 8. The catalyst article of embodiment 6, wherein the ceria and zirconia of the ceria-zirconia composite are each present in an amount ranging from about 25 to about 60 weight percent, based on the total weight of the ceria-zirconia composite.

[0408] 9. The catalytic article of embodiment 4, wherein the refractory metal oxide material is alumina.

[0409] 10. The catalyst article of any one of embodiments 1-9, wherein the SCR catalyst comprises a mixed metal oxide component.

[0410] 11. The mixed metal oxide components are FeTiO3, FeAl2O3, MgTiO3, MgAlO3, MnO x11. The catalytic article of embodiment 10, wherein the metal oxide is selected from the group consisting of V2O5 / TiO2, CuTiO3, CeZrO2, TiZrO2, V2O5 / TiO2 and mixtures thereof.

[0411] 12. The catalytic article of embodiment 10 or 11, wherein the mixed metal oxide component comprises titania and vanadia.

[0412] 13. The catalytic article of embodiment 11 or 12, wherein the vanadia is present in the mixed metal oxide component in an amount ranging from about 1 to about 10 weight percent, based on the total weight of the mixed metal oxide component.

[0413] 14. The catalytic article of any one of embodiments 10-13, wherein the mixed metal oxide component further comprises tungsten (W).

[0414] 15. The catalyst article of any one of embodiments 1-14, wherein the SCR catalyst comprises a metal ion-exchanged molecular sieve.

[0415] 16. The catalytic article of embodiment 15, wherein the metal is selected from Cu, Co, Ni, La, Mn, Fe, V, Ag, Ce, Nd, Mo, Hf, Y, W, and combinations thereof.

[0416] 17. The catalytic article of embodiment 16, wherein the metal is Cu, Fe, or a combination thereof.

[0417] 18. The catalytic article of any one of embodiments 15-17, wherein the metal is present in an amount, calculated as metal oxide, of about 0.1% to about 10% by weight, based on the weight of the ion-exchanged molecular sieve.

[0418] 19. The catalytic article of any one of embodiments 15-18, wherein the molecular sieve is a zeolite.

[0419] 20. The catalyst article of embodiment 19, wherein the zeolite has a framework structure type selected from AEI, AFT, AFV, AFX, AVL, CHA, DDR, EAB, EEI, ERI, IFY, IRN, KFI, LEV, LTA, LTN, MER, MWF, NPT, PAU, RHO, RTE, RTH, SAS, SAT, SAV, SFW, TSC, and UFI, and combinations thereof.

[0420] 21. The catalytic article of embodiment 20, wherein the framework structure type is CHA.

[0421] 22. The catalytic article of any one of embodiments 19-21, wherein the zeolite included in the catalytic composition, more preferably having a framework structure type CHA, has an average crystal size, as determined by scanning electron microscopy, of at least 0.5 micrometers, preferably in the range of 0.5 to 1.5 micrometers, more preferably in the range of 0.6 to 1.0 micrometers, more preferably in the range of 0.6 to 0.8 micrometers.

[0422] 23. The catalyst article of any one of embodiments 1-22, wherein the platinum group metal impregnated on the porous support is palladium impregnated on zirconia, and the SCR catalyst comprises one or more of mixed metal oxides and zeolites comprising one or more of Cu and Fe.

[0423] 24. The catalyst article of embodiment 23, wherein the SCR catalyst comprises a zeolite comprising Cu, preferably a zeolite having a framework structure type CHA.

[0424] 25. The catalytic article of any one of embodiments 1-24, wherein the substrate is a honeycomb substrate.

[0425] 26. The catalytic article of embodiment 25, wherein the honeycomb substrate is metal or ceramic.

[0426] 27. The catalytic article of embodiment 25 or 26, wherein the honeycomb substrate is a flow-through substrate or a wall-flow filter.

[0427] 28. The catalyst article of any one of embodiments 1-27, wherein the catalyst composition comprises a first layer and a second layer, the first layer comprising an SCR catalyst, and the second layer comprising a PGM impregnated on a porous support.

[0428] 29. The catalytic article of embodiment 28, wherein the first layer is disposed directly on the substrate and the second layer is disposed on top of the first layer.

[0429] 30. The catalytic article of embodiment 28, wherein the second layer is disposed directly on the substrate and the first layer is disposed on top of the second layer.

[0430] 31. The catalytic article of embodiment 28, wherein the first layer and the second layer are disposed directly on the substrate in a zone configuration.

[0431] 32. The catalyst article of any one of embodiments 28-31, wherein the SCR catalyst of the first layer comprises a metal oxide mixture and one or more of Cu and Fe, preferably a metal oxide mixture, more preferably V2O5 / TiO2.

[0432] 33. The catalytic article of any one of embodiments 28-32, wherein the PGM impregnated on the porous support is palladium or rhodium impregnated on ceria-zirconia.

[0433] 34. The catalyst article of any one of embodiments 1-27, wherein the substrate has an inlet end, an outlet end, and a substrate length spanning from the inlet end to the outlet end of the substrate, the substrate comprising a plurality of passages defined by an interior wall of the substrate, and the catalyst composition comprises a first layer and a second layer, the first layer comprising a PGM impregnated in a porous support, and the second layer comprising an SCR catalyst.

[0434] 35. The catalyst article of embodiment 34, wherein the first layer extends from the inlet end to the outlet end of the substrate for 5 to 95% of the length of the substrate, and the second layer extends from the outlet end to the inlet end for 5 to 95% of the length of the substrate.

[0435] 36. The catalyst article of embodiment 34 or 35, wherein the first layer extends from the inlet end to the outlet end of the substrate over 20 to 80%, preferably 30 to 70%, more preferably 40 to 60%, more preferably 45 to 55% of the substrate length, and the second layer extends from the outlet end to the inlet end over 20 to 80%, preferably 30 to 70%, more preferably 40 to 60%, more preferably 45 to 55% of the substrate length.

[0436] 37. The catalytic article of any one of embodiments 34-36, wherein the first layer comprises palladium impregnated in one or more of zirconia and alumina.

[0437] 38. The first layer contains 5-100g / ft2 of elemental palladium. 3 in the range of 0.71 to 2.82 g / l (20 to 80 g / ft 3 ), more preferably in the range of 1.06 to 2.47 g / l (30 to 70 g / ft 3 ), more preferably in the range of 1.24 to 1.94 g / l (35 to 55 g / ft 3 ), more preferably in the range of 1.41 to 1.77 g / l (40 to 50 g / ft 3 38. The catalytic article of any one of embodiments 34-37, comprising palladium at a loading in the range of 0.15 to 0.25.

[0438] 39. The catalytic article of any one of embodiments 34-38, wherein 98-100%, preferably 99-100%, more preferably 99.5-100%, by weight, of the first layer consists of palladium impregnated on one or more of zirconia and alumina.

[0439] 40. The catalyst article of any one of embodiments 34-39, wherein the SCR catalyst comprises a zeolite comprising Cu, preferably a zeolite having structure type CHA.

[0440] 41. The catalytic article of any one of embodiments 34 to 40, wherein the second layer further comprises a metal oxide binder, preferably a metal oxide binder as defined in embodiment 27.

[0441] 42. The catalyst article of any one of embodiments 34 to 41, wherein 98 to 100 wt. %, preferably 99 to 100 wt. %, more preferably 99.5 to 100 wt. % of the second layer consists of a zeolite containing Cu, preferably a zeolite having structure type CHA, and a metal oxide binder material as defined in embodiment 27.

[0442] 43. The catalytic article of any one of embodiments 1-27, wherein the catalytic composition comprises, preferably consists of, a single layer.

[0443] 44. The catalyst article of any one of embodiments 1-43, which is the first catalyst according to (i) of an exhaust gas treatment system according to any one of embodiments 1′-87′.

[0444] 45. The catalyst article of any one of embodiments 1 to 43, which is a second catalyst according to (ii) of an exhaust gas treatment system according to any one of embodiments 1 to 113.

[0445] 46. ​​Contacting the gas stream with a catalytic article according to any one of embodiments 1-45, thereby reducing nitrogen oxides (NO ) in the exhaust gas stream. x ) and hydrocarbons (HC) are reduced.

[0446] 47. An emission treatment system for treating an exhaust gas stream, comprising: an engine producing an exhaust gas stream; 46. ​​The catalytic article of any one of embodiments 1-45, located downstream of an engine in fluid communication with the exhaust gas stream, and adapted to reduce NOx and HC in the exhaust gas stream to form a treated exhaust gas stream; and An injector adapted to add a reductant to the exhaust gas stream upstream of the catalyst article An emission treatment system comprising:

[0447] 48. The emissions treatment system of embodiment 47, wherein the catalytic article is positioned to directly receive the engine exhaust gas stream produced by the engine without an intervening catalytic article.

[0448] 49. The emissions treatment system of embodiment 47 or 48, further comprising an injector adapted to add hydrocarbons to the exhaust gas stream, the injector being located upstream of the catalytic article.

[0449] 50. The emissions treatment system of any one of embodiments 47-49, further comprising a diesel oxidation catalyst located downstream from the catalyst article.

[0450] 51. The emission treatment system of any one of embodiments 47-49, further comprising a soot filter located downstream from the catalytic article.

[0451] 52. The emission treatment system of any one of embodiments 47-51, wherein the engine is a diesel engine.

[0452] 53. The emission treatment system of any one of embodiments 47-52, wherein the reducing agent comprises ammonia or an ammonia precursor.

[0453] 54. An exhaust gas treatment system for treating an exhaust gas stream exiting a diesel engine, said exhaust gas treatment system having an upstream end for introducing said exhaust gas stream into said exhaust gas treatment system, said exhaust gas treatment system comprising: 43. The catalytic article of any one of embodiments 31 to 42, having an inlet end and an outlet end. Equipped with the catalytic article is a first catalytic article in the exhaust gas treatment system downstream of an upstream end of the exhaust gas treatment system, and an inlet end of the catalytic article is disposed upstream of an outlet end of the catalytic article; Exhaust gas treatment system.

[0454] 55. The exhaust gas treatment system of embodiment 54, further comprising one or more of a diesel oxidation catalyst, a selective catalytic reduction catalyst, and an ammonia oxidation catalyst located downstream of the catalyst article.

[0455] 56. The exhaust gas treatment system of embodiment 54 or 55, further comprising an ammonia oxidation catalyst located downstream of the catalyst article, the ammonia oxidation catalyst having an inlet end and an outlet end, the outlet end of the catalyst article being in fluid communication with the inlet end of the ammonia oxidation catalyst, and no catalyst for treating exhaust gases exiting the second catalyst is located in the exhaust gas treatment system between the outlet end of the catalyst article and the inlet end of the ammonia oxidation catalyst.

[0456] 57. The exhaust gas treatment system of embodiment 56, wherein the ammonia oxidation catalyst is as defined in any one of embodiments 93-111.

[0457] 58. The exhaust gas treatment system of any one of embodiments 54-57, further comprising a particulate filter, the particulate filter having an inlet end and an outlet end and located downstream of the catalyst article, preferably the outlet end of the catalyst article being in fluid communication with the inlet end of the particulate filter, and no catalyst for treating the exhaust gas stream exiting the second catalyst is located in the exhaust gas treatment system between the outlet end of the catalyst article and the inlet end of the particulate filter.

[0458] 59. The exhaust gas treatment system of embodiment 58, wherein the particulate filter is a catalyzed particulate filter.

[0459] 60. The exhaust gas treatment system of any one of embodiments 54-59, further comprising an injector for injecting a fluid into the exhaust gas stream exiting the diesel engine, wherein the injector is preferably located upstream of the catalytic article and downstream of the upstream end of the exhaust gas treatment system.

[0460] 61. The exhaust gas treatment system of embodiment 60, wherein the fluid is an aqueous urea solution.

[0461] The present invention is further exemplified by the following second set of embodiments, and combinations of embodiments derived from the indicated dependent and forward references. The second set of embodiments may be combined with any one of the above first set of embodiments and the following third set of embodiments.

[0462] 1'. An exhaust gas treatment system for treating an exhaust gas stream exiting a diesel engine, said exhaust gas treatment system having an upstream end for introducing said exhaust gas stream into said exhaust gas treatment system, said exhaust gas treatment system comprising: (i) a first catalyst having an inlet end and an outlet end and comprising a coating disposed on a substrate, the coating comprising palladium supported on an oxide material comprising zirconium, and further comprising one or more of vanadium oxide and a zeolite material comprising one or more of copper and iron; or A first catalyst having an inlet end and an outlet end, the catalyst article of any one of embodiments 1 to 43. (ii) a second catalyst having an inlet end and an outlet end and comprising a coating disposed on a substrate, the coating comprising a platinum group metal supported on an oxide material, and further comprising one or more of vanadium oxide, tungsten oxide, and a zeolite material comprising one or more of copper and iron. Equipped with the first catalyst according to (i) is a first catalyst of the exhaust gas treatment system downstream of an upstream end of the exhaust gas treatment system, the inlet end of the first catalyst being disposed upstream of the outlet end of the first catalyst; In the exhaust gas treatment system, a second catalyst according to (ii) is located downstream of the first catalyst according to (i), and an inlet end of the second catalyst is arranged upstream of an outlet end of the second catalyst. Exhaust gas treatment system.

[0463] 2'. The exhaust gas treatment system of embodiment 1', wherein an outlet end of the first catalyst according to (i) is in fluid communication with an inlet end of the second catalyst according to (ii), and wherein no catalyst for treating the exhaust gas flow exiting the first catalyst is located in the exhaust gas treatment system between the outlet end of the first catalyst according to (i) and the inlet end of the second catalyst according to (ii).

[0464] 3'. The exhaust gas treatment system of embodiment 1' or 2', wherein the first catalyst comprises a hydrocarbon (HC) oxidizing component and a nitrogen oxide (NOx) reducing component.

[0465] 4'. The exhaust gas treatment system of any one of embodiments 1'-3', wherein 90-100 wt.%, preferably 95-100 wt.%, more preferably 99-100 wt.% of the oxide material in the coating of the first catalyst consists of zirconium and oxygen, preferably zirconia.

[0466] 5'. The exhaust gas treatment system of any one of embodiments 1'-4', wherein the first catalytic coating according to (i) comprises a zeolite material containing one or more of copper and iron.

[0467] 6'. The exhaust gas treatment system of any one of embodiments 1'-5', wherein the zeolitic material included in the coating of the first catalyst has a framework structure of type AEI, GME, CHA, MFI, BEA, FAU, MOR, or a mixture of two or more thereof, preferably a framework structure of type AEI, CHA, BEA, or a mixture of two or more thereof, more preferably a framework structure of type CHA or AEI, more preferably a framework structure of type CHA.

[0468] 7'. The exhaust gas treatment system of any one of embodiments 1'-6', wherein the zeolitic material included in the coating of the first catalyst, preferably having framework type CHA, has an average crystal size, as determined by scanning electron microscopy, of at least 0.5 micrometers, preferably in the range of 0.5 to 1.5 micrometers, more preferably in the range of 0.6 to 1.0 micrometers, and more preferably in the range of 0.6 to 0.8 micrometers.

[0469] 8'. The exhaust gas treatment system of any one of embodiments 5' to 7', wherein the zeolite material included in the coating of the first catalyst comprises copper, wherein the amount of copper in the zeolite material, calculated as CuO, is preferably in the range of 0.1 to 10.0 wt.%, more preferably in the range of 2.0 to 7.0 wt.%, more preferably in the range of 2.5 to 5.5 wt.%, more preferably in the range of 2.5 to 3.5 wt.%, based on the total weight of the zeolite material; and the amount of iron in the zeolite material, calculated as Fe2O3, is preferably in the range of 0 to 0.01 wt.%, more preferably in the range of 0 to 0.0 ... based on the total weight of the zeolite material.

[0470] 9'. The exhaust gas treatment system of embodiment 7' or 8', wherein 95 to 100 wt%, preferably 98 to 100 wt%, more preferably 99 to 100 wt% of the framework structure of the zeolitic material consists of one or more of Si, Al, O, and optionally H and P, and wherein the molar ratio of Si to Al in the framework structure, calculated as the molar ratio of SiO2:Al2O3, is preferably in the range of 2:1 to 50:1, more preferably in the range of 4:1 to 45:1, more preferably in the range of 10:1 to 40:1, more preferably in the range of 20:1 to 35:1.

[0471] 10'. The exhaust gas treatment system of any one of embodiments 1' to 6', wherein the zeolite material in the coating of the first catalyst comprises iron, the amount of iron in the zeolite material, calculated as Fe2O3, being preferably in the range of 0.1 to 10.0 wt.%, more preferably in the range of 1.0 to 7.0 wt.%, more preferably in the range of 2.5 to 5.5 wt.%, based on the total weight of the zeolite material; and preferably 95 to 100 wt.%, more preferably 98 to 100 wt.%, more preferably 99 to 100 wt.% of the framework structure of the zeolite material consists of one or more of Si, Al, O, and optionally H and P, wherein the molar ratio of Si to Al in the framework structure, calculated as the molar ratio of SiO2:Al2O3, is preferably in the range of 2:1 to 50:1, more preferably in the range of 4:1 to 45:1, more preferably in the range of 10:1 to 40:1, more preferably in the range of 20:1 to 35:1.

[0472] 11'. The first catalytic coating further comprises a metal oxide binder, the metal oxide binder preferably comprising one or more of zirconia, alumina, titania, silica, and an oxide mixture comprising two or more of Zr, Al, Ti, and Si, more preferably one or more of alumina and zirconia, more preferably zirconia; The first catalyst coating is 1.22 to 12.20 g / L (0.02 to 0.2 g / in 3 ), more preferably in the range of 4.27 to 9.15 g / L (0.07 to 0.15 g / in 3 The exhaust gas treatment system of any one of embodiments 1'-10', more preferably comprising a metal oxide binder at a loading in the range of 100 to 1500 mW.

[0473] 12′. The exhaust gas treatment system of any one of embodiments 1′ to 11′, wherein the coating of the first catalyst according to (i) comprises vanadium oxide, the vanadium oxide preferably being one or more of vanadium(V) oxide and vanadium(IV) oxide, the vanadium oxide optionally containing one or more of tungsten, iron, and antimony.

[0474] 13′. The exhaust gas treatment system of embodiment 12′, wherein the vanadium oxide is supported on an oxide material comprising one or more of titanium, silicon, and zirconium, preferably on an oxide material comprising one or more of titanium and silicon, more preferably on an oxide material comprising one or more of titania and silica, more preferably on titania, and the titania optionally contains one or more of tungsten and silicon.

[0475] 14'. The exhaust gas treatment system of any one of embodiments 1'-13', wherein the substrate of the first catalyst comprises a ceramic material or a metallic material.

[0476] 15'. the substrate of the first catalyst comprises, preferably consists of, a ceramic material, the ceramic material preferably comprising, more preferably consisting of, one or more of alumina, silica, silicate, aluminosilicate, preferably cordierite or mullite, aluminotitanate, silicon carbide, zirconia, magnesia, preferably spinel and titania, more preferably one or more of silicon carbide and cordierite, more preferably cordierite; or The exhaust gas treatment system of any one of embodiments 1' to 14', wherein the substrate of the first catalyst comprises, preferably consists of, a metallic material, and the metallic material preferably comprises, more preferably consists of, oxygen, and one or more of iron, chromium, and aluminum.

[0477] 16'. The exhaust gas treatment system of any one of embodiments 1'-15', wherein the substrate of the first catalyst is a monolith, preferably a honeycomb monolith, more preferably a flow-through honeycomb monolith.

[0478] 17'. The exhaust gas treatment system of any one of embodiments 1'-16', wherein the first catalyst substrate has a substrate length, and the first catalyst coating is disposed on 20-100%, preferably 50-100%, more preferably 75-100%, more preferably 95-100%, more preferably 99-100% of the substrate length.

[0479] 18. The first catalyst coating is 0.035 to 2.82 g / L (1 to 80 g / ft 3 ), preferably in the range of 0.53 to 2.12 g / l (15 to 60 g / ft 3 ), more preferably in the range of 0.71 to 1.77 g / l (20 to 50 g / ft 3 ), more preferably in the range of 0.88 to 1.59 g / l (25 to 45 g / ft 3 ), more preferably in the range of 0.88 to 1.24 g / l (25 to 35 g / ft 3 17. The exhaust gas treatment system of any one of embodiments 1' to 17', comprising palladium at a loading in the range of 1.

[0480] 19. The first catalyst coating is 61.02 to 274.61 g / L (1.0 to 4.5 g / in 3 ), preferably in the range of 91.54 to 244.10 g / L (1.5 to 4.0 g / in 3 ), more preferably in the range of 122.05 to 183.07 g / L (2.0 to 3.0 g / in 3 ), more preferably in the range of 128.15 to 170.87 g / L (2.1 to 2.8 g / in 3 ), more preferably in the range of 128.15 to 158.66 g / L (2.1 to 2.6 g / in 3 19. The exhaust gas treatment system of any one of embodiments 1'-18', comprising the zeolite material at a loading in the range of 0.15 to 0.25 wt %.

[0481] 20. The first catalyst coating is 122.04 to 366.14 g / L (2.0 to 6.0 g / in 3 ), preferably in the range of 183.07 to 335.63 g / L (3.0 to 5.5 g / in 3), more preferably in the range of 244.1 to 305.12 g / L (4.0 to 5.0 g / in 3 19. The exhaust gas treatment system of any one of embodiments 1'-19', comprising vanadium oxide at a loading in the range of

[0482] 21'. 95 to 100 mass %, preferably 98 to 100 mass %, more preferably 99 to 100 mass %, more preferably 99.5 to 100 mass % of the coating of the first catalyst comprises palladium supported on an oxide material, preferably consisting of the above palladium; The exhaust gas treatment system of any one of embodiments 1' to 20', wherein 99-100 wt.% of the oxide material consists of zirconium and oxygen, preferably zirconia, and a copper-containing zeolite material having a framework structure of type CHA, and a metal oxide binder material preferably as defined in embodiment 11'.

[0483] 22'. The exhaust gas treatment system of any one of embodiments 1'-20', wherein 95-100%, preferably 98-100%, more preferably 99-100%, more preferably 99.5-100%, by weight, of the coating of the first catalyst comprises, preferably consists of, palladium supported on an oxide material, and 99-100%, by weight, of the oxide material consists of zirconium and oxygen, preferably zirconia, and vanadium oxide supported on titania, the titania optionally containing one or more of tungsten and silicon.

[0484] 23'. The exhaust gas treatment system of any one of embodiments 1'-22', wherein the first catalyst has a selective catalytic reduction (SCR) component and a diesel oxidation component.

[0485] 24'. The exhaust gas treatment system of any one of embodiments 1'-23', wherein 0-0.0035 g / L, preferably 0-0.00035 g / L, more preferably 0-0.000035 g / L, of one or more of platinum, iridium, osmium, and rhodium is included in the coating of the first catalyst, and more preferably 0-0.000035 g / L of platinum, iridium, osmium, and rhodium is included in the coating of the first catalyst.

[0486] 25′. The exhaust gas treatment system of any one of embodiments 1′-23′, wherein the coating of the first catalyst is free of platinum, preferably free of platinum and rhodium, and more preferably free of platinum, rhodium, iridium, and osmium.

[0487] 26'. 0 to 2 wt. %, preferably 0 to 1 wt. %, more preferably 0 to 0.1 wt. % of the palladium-supporting oxide material contained in the first catalyst coating consists of ceria and alumina, more preferably 0 to 0.1 wt. % of the oxide material contained in the first catalyst coating consists of ceria, alumina, titania, lanthana and baria, or The exhaust gas treatment system of any one of embodiments 1' to 25', wherein the palladium-supporting oxide material included in the coating of the first catalyst is free of ceria and alumina, preferably free of ceria, alumina and titania, and more preferably free of ceria, alumina, titania, lanthana and baria.

[0488] 27'. The exhaust gas treatment system of embodiment 1', wherein the first catalyst is a catalyst article according to any one of embodiments 1-30 and 43.

[0489] 28'. The exhaust gas treatment system of any one of embodiments 1' to 27', wherein the second catalyst according to (ii) comprises a nitrogen oxide (NOx) reducing component and an ammonia oxidizing component.

[0490] 29'. The exhaust gas treatment system of any one of embodiments 1' to 28', wherein the second catalyst according to (ii) is an ammonia oxidation (AMOX) catalyst.

[0491] 30'. The exhaust gas treatment system of any one of embodiments 1' to 29', wherein the second catalytic coating according to (ii) comprises a zeolite material containing one or more of copper and iron.

[0492] 31′. The exhaust gas treatment system of any one of embodiments 1′ to 30′, wherein the zeolitic material included in the coating of the second catalyst has a framework structure of type AEI, GME, CHA, MFI, BEA, FAU, MOR, or a mixture of two or more thereof, preferably a framework structure of type AEI, CHA, BEA, or a mixture of two or more thereof, more preferably a framework structure of type CHA or AEI, and more preferably a framework structure of type CHA.

[0493] 32'. The exhaust gas treatment system of any one of embodiments 1' to 31', wherein the zeolitic material included in the coating of the second catalyst, preferably having framework type CHA, has an average crystallite size, as determined by scanning electron microscopy, of at least 0.5 micrometers, preferably in the range of 0.5 to 1.5 micrometers, more preferably in the range of 0.6 to 1.0 micrometers, and more preferably in the range of 0.6 to 0.8 micrometers.

[0494] 33'. The exhaust gas treatment system of any one of embodiments 30' to 32', wherein the zeolite material in the coating of the second catalyst comprises copper, wherein the amount of copper in the zeolite material, calculated as CuO, is preferably in the range of 0.1 to 10.0 wt.%, more preferably in the range of 2.0 to 7.0 wt.%, more preferably in the range of 2.5 to 5.5 wt.%, more preferably in the range of 2.5 to 3.5 wt.%, based on the total weight of the zeolite material; and the amount of iron in the zeolite material, calculated as Fe2O3, is preferably in the range of 0 to 0.01 wt.%, more preferably in the range of 0 to 0.0 ... based on the total weight of the zeolite material.

[0495] 34'. The exhaust gas treatment system of any one of embodiments 30'-33', wherein 95-100 wt%, preferably 98-100 wt%, more preferably 99-100 wt% of the framework structure of the zeolitic material consists of one or more of Si, Al, O, and optionally H and P, and wherein the molar ratio of Si to Al in the framework structure, calculated as the molar ratio of SiO2:Al2O3, is preferably in the range of 2:1 to 50:1, more preferably in the range of 4:1 to 40:1, more preferably in the range of 10:1 to 40:1, more preferably in the range of 20:1 to 35:1.

[0496] 35′. The exhaust gas treatment system of any one of embodiments 30′ to 32′, wherein the zeolitic material in the coating of the second catalyst comprises iron, the amount of iron in the zeolitic material, calculated as Fe2O3, preferably in the range of 0.1 to 10.0 wt.%, more preferably in the range of 1.0 to 7.0 wt.%, more preferably in the range of 2.5 to 5.5 wt.%, based on the total weight of the zeolitic material; and wherein preferably 95 to 100 wt.%, more preferably 98 to 100 wt.%, more preferably 99 to 100 wt.% of the framework structure of the zeolitic material consists of one or more of Si, Al, O, and optionally H and P, and wherein the molar ratio of Si to Al in the framework structure, calculated as the molar ratio of SiO2:Al2O3, is preferably in the range of 2:1 to 50:1, more preferably in the range of 4:1 to 40:1, more preferably in the range of 10:1 to 40:1, more preferably in the range of 20:1 to 35:1.

[0497] 36'. the second catalytic coating further comprises a metal oxide binder, the metal oxide binder preferably comprising one or more of zirconia, alumina, titania, silica, and an oxide mixture comprising two or more of Zr, Al, Ti, and Si, more preferably one or more of alumina and zirconia, more preferably zirconia; The second catalyst coating is 1.22 to 12.20 g / L (0.02 to 0.2 g / in 3 ), more preferably in the range of 4.27 to 9.15 g / L (0.07 to 0.15 g / in 3 The exhaust gas treatment system of any one of embodiments 1'-35', more preferably comprising a metal oxide binder in the coating at a loading in the range of 0.1 to 0.25.

[0498] 37′. The exhaust gas treatment system of any one of embodiments 1′-36′, wherein the platinum group metal included in the coating of the second catalyst is one or more of platinum, palladium, and rhodium, preferably one or more of platinum and palladium.

[0499] 38'. The platinum group metal contained in the second catalytic coating is a mixture of platinum and palladium; The exhaust gas treatment system of embodiment 37', wherein the mass ratio of platinum:palladium in the coating of the second catalyst, calculated as elemental platinum and elemental palladium, is preferably in the range of 1:1 to 30:1, more preferably in the range of 5:1 to 20:1, more preferably in the range of 8:1 to 12:1, more preferably in the range of 9:1 to 11:1.

[0500] 39'. The exhaust gas treatment system of embodiment 37', wherein the platinum group metal in the second catalytic coating is platinum.

[0501] 40′. The exhaust gas treatment system of any one of embodiments 1′-39′, wherein the platinum group metal-supporting oxide material included in the coating of the second catalyst comprises, or preferably consists of, one or more of alumina, zirconia, silica, titania, and ceria, preferably one or more of alumina, silica, and zirconia, more preferably one or more of zirconia and alumina.

[0502] 41′. The exhaust gas treatment system of any one of embodiments 1′ to 40′, wherein 20 to 100%, preferably 40 to 100%, more preferably 60 to 100%, more preferably 70 to 90%, more preferably 75 to 85%, by weight, of the platinum group metal-supporting oxide material in the second catalyst coating consists of alumina.

[0503] 42′. The exhaust gas treatment system of any one of embodiments 1′ to 41′, wherein the second catalytic coating comprises vanadium oxide, preferably one or more of vanadium(V) oxide and vanadium(IV) oxide, and the vanadium oxide optionally contains one or more of tungsten, iron, and antimony.

[0504] 43′. The exhaust gas treatment system of embodiment 42′, wherein the vanadium oxide is supported on an oxide material comprising one or more of titanium, silicon, and zirconium, preferably on an oxide material comprising one or more of titanium and silicon, more preferably on an oxide material comprising one or more of titania and silica, more preferably on titania, and the titania optionally contains one or more of tungsten and silicon.

[0505] 44′. The exhaust gas treatment system of any one of embodiments 1′ to 43′, wherein the second catalytic coating comprises tungsten oxide, the tungsten oxide preferably being tungsten trioxide, and the tungsten oxide optionally comprises one or more of iron and antimony.

[0506] 45′. The exhaust gas treatment system of embodiment 44′, wherein the tungsten oxide is supported on an oxide material comprising one or more of titanium and zirconium, preferably on an oxide material comprising one or more of titania and zirconia, more preferably on titania.

[0507] 46′. The exhaust gas treatment system of any one of embodiments 1′ to 45′, wherein the second catalytic coating comprises vanadium oxide and tungsten oxide, wherein the tungsten oxide is tungsten trioxide, wherein the vanadium oxide is preferably supported on an oxide material comprising one or more of titanium, silicon, and zirconium, preferably on an oxide material comprising one or more of titanium and silicon, more preferably on an oxide material comprising one or more of titania and zirconia, more preferably on titania, wherein the titania optionally contains one or more of tungsten and silicon, and wherein the tungsten oxide is preferably supported on an oxide material comprising one or more of titanium and zirconium, preferably on an oxide material comprising one or more of titania and zirconia, more preferably on titania.

[0508] 47'. The exhaust gas treatment system of any one of embodiments 1'-46', wherein the substrate of the second catalyst comprises a ceramic material or a metallic material.

[0509] 48′. The exhaust gas treatment system of any one of embodiments 1′-47′, wherein the substrate of the second catalyst comprises, preferably consists of, a ceramic material, the ceramic material preferably comprising, more preferably consisting of, one or more of alumina, silica, silicate, aluminosilicate, preferably cordierite or mullite, aluminotitanate, silicon carbide, zirconia, magnesia, preferably spinel and titania, more preferably one or more of silicon carbide and cordierite, more preferably cordierite.

[0510] 49′. The exhaust gas treatment system of any one of embodiments 1′ to 47′, wherein the substrate of the second catalyst comprises, preferably consists of, a metallic material, and the metallic material preferably comprises, more preferably consists of, oxygen and one or more of iron, chromium, and aluminum.

[0511] 50'. The exhaust gas treatment system of any one of embodiments 1' to 49', wherein the substrate of the second catalyst is a monolith, preferably a honeycomb monolith, more preferably a flow-through honeycomb monolith.

[0512] 51'. The exhaust gas treatment system of any one of embodiments 1' to 50', wherein the second catalyst substrate has a substrate length, and the second catalyst coating is disposed on 20-100%, preferably 50-100%, more preferably 75-100%, more preferably 95-100%, more preferably 99-100% of the substrate length.

[0513] 52. The second catalytic coating has a platinum group metal content of 0.035-0.53 g / L (1-15 g / ft). 3 ), preferably in the range of 0.11 to 0.35 g / l (3 to 10 g / ft 3), more preferably in the range of 0.16 to 0.32 g / l (4.5 to 9.0 g / ft 3 ), more preferably in the range of 0.26 to 0.30 g / l (7.5 to 8.5 g / ft 3 The exhaust gas treatment system of any one of embodiments 1' to 51', comprising a platinum group metal at a loading in the range of 0.1 to 0.5.

[0514] 53. The second catalyst coating is 30.51 to 335.63 g / L (0.5 to 5.5 g / in 3 ), more preferably in the range of 91.54 to 305.12 g / L (1.5 to 5.0 g / in 3 ), more preferably in the range of 122.05 to 244.09 g / L (2.0 to 4.0 g / in 3 ), more preferably in the range of 122.05 to 213.58 g / L (2.0 to 3.5 g / in 3 ) zeolite material at a loading in the range of 1.52.

[0515] 54. The second catalyst coating is 122.04 to 366.14 g / L (2.0 to 6.0 g / in 3 ), preferably in the range of 183.07 to 335.63 g / L (3.0 to 5.5 g / in 3 ), more preferably in the range of 244.1 to 305.12 g / L (4.0 to 5.0 g / in 3 53. The exhaust gas treatment system of any one of embodiments 1' to 53', comprising one or more of vanadium oxide and tungsten oxide at a loading in the range of

[0516] 55'. An exhaust gas treatment system according to any one of embodiments 1' to 38' and 47' to 53', wherein the second catalyst coating comprises, or preferably consists of, a mixture of platinum and palladium (the mass ratio of platinum to palladium, calculated as Pt:Pd, is preferably in the range of 5:1 to 15:1, more preferably 8:1 to 12:1, more preferably 9:1 to 11:1) on the surface of an oxide material comprising a mixture of zirconia and alumina, a zeolite material having a CHA-type framework structure and containing copper, and a metal oxide binder material, preferably as defined in embodiment 36'.

[0517] 56′. The exhaust gas treatment system of any one of embodiments 1′ to 55′, wherein 95 to 100%, preferably 98 to 100%, more preferably 99 to 100%, more preferably 99.5 to 100%, by weight of the coating of the second catalyst comprises a mixture of platinum and palladium supported on the surface of an oxide material comprising a mixture of zirconia and alumina and a zeolite material having a framework structure of type CHA and containing copper, the mass ratio of platinum to palladium, calculated as Pt:Pd, preferably in the range of 5:1 to 15:1, more preferably in the range of 8:1 to 12:1, more preferably in the range of 9:1 to 11:1, and preferably in the range of 10:1 to 12:1, more preferably in the range of 11:1 to 12:1, calculated as Pt:Pd), and a metal oxide binder material preferably as defined in embodiment 36′.

[0518] 57'. The coating of the first catalyst comprises, or preferably consists of, palladium supported on an oxide material comprising zirconium, preferably consisting of zirconia, and a zeolite material having a type CHA framework structure and comprising copper, and a metal oxide binder as defined in embodiment 11'; The exhaust gas treatment system of any one of embodiments 1' to 55', wherein the coating of the second catalyst comprises, and preferably consists of, an oxide material comprising a mixture of zirconia and alumina, and a mixture of platinum and palladium supported on a zeolite material having a type CHA framework stru...

Claims

1. 1. An exhaust gas treatment system for treating an exhaust gas stream exiting a diesel engine, the exhaust gas treatment system having an upstream end for introducing the exhaust gas stream into the exhaust gas treatment system, the exhaust gas treatment system comprising: (i) a first catalyst having an inlet end and an outlet end and comprising a coating disposed on a substrate, the coating comprising palladium supported on an oxide material comprising zirconium, and further comprising one or more of vanadium oxide, and a zeolitic material comprising copper having a type CHA framework structure; (ii) a second catalyst having an inlet end and an outlet end and comprising a coating disposed on a substrate, the coating comprising a platinum group metal supported on an oxide material, and further comprising one or more of vanadium oxide, tungsten oxide, and a zeolite material comprising one or more of copper and iron. Equipped with the first catalyst according to (i) is a first catalyst of the exhaust gas treatment system downstream of an upstream end of the exhaust gas treatment system, an inlet end of the first catalyst being disposed upstream of an outlet end of the first catalyst; In an exhaust gas treatment system, a second catalyst according to (ii) is located downstream of the first catalyst according to (i), with an inlet end of the second catalyst being disposed upstream of an outlet end of the second catalyst. Exhaust gas treatment systems.

2. 10. The exhaust gas treatment system of claim 1, wherein the first catalytic coating according to (i) comprises vanadium oxide, the vanadium oxide optionally containing one or more of tungsten, iron, and antimony.

3. The first catalyst coating has a concentration of 0.035 to 2.82 g / l (1 to 80 g / ft ３ 3. The exhaust gas treatment system of claim 1, further comprising palladium at a loading in the range of 0.1 to 1.0% by weight.

4. The first catalyst coating is 61.02 to 274.61 g / l (1.0 to 4.5 g / in ３ 4. The exhaust gas treatment system of claim 1, further comprising a zeolite material at a loading in the range of 0.5 to 1000 nm.

5. The first catalyst coating is 2.0 to 6.0 g / in ３ 5. The exhaust gas treatment system of claim 1, further comprising vanadium oxide in a loading range of 0.1 to 0.5 vanadium oxide.

6. The exhaust gas treatment system of any one of claims 1 to 5, wherein the first catalyst does not include an additional coating.

7. The exhaust gas treatment system of any one of claims 1 to 6, wherein the second catalytic coating according to (ii) comprises a zeolitic material containing one or more of copper and iron.

8. 8. The exhaust gas treatment system according to claim 1, wherein the zeolitic material contained in the coating of the second catalyst has a framework structure of type AEI, GME, CHA, MFI, BEA, FAU, MOR or a mixture of two or more thereof.

9. 9. The exhaust gas treatment system of any one of claims 1 to 8, wherein the second catalytic coating comprises vanadium oxide, the vanadium oxide optionally containing one or more of tungsten, iron and antimony.

10. 10. The exhaust gas treatment system of any one of claims 1 to 9, wherein the platinum group metal included in the second catalytic coating is one or more of platinum, palladium and rhodium.

11. 11. An exhaust gas treatment system as claimed in any one of claims 1 to 10, further comprising an injector for injecting a fluid into an exhaust gas stream exiting the diesel engine, said injector being located upstream of the first catalyst and downstream of the upstream end of the exhaust gas treatment system.

12. 1. A method for simultaneously performing selective catalytic reduction of NOx, oxidation of hydrocarbons, oxidation of nitric oxide, and oxidation of ammonia, comprising: (1) providing an exhaust gas stream from a diesel engine, the exhaust gas stream containing one or more of NOx, ammonia, nitric oxide, and hydrocarbons; (2) A step of passing the exhaust gas flow supplied in (1) through the exhaust gas system according to any one of claims 1 to 11. The method includes:

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