SCR catalysts with mixed oxides and H-zeolites

Abstract

Nitrogen oxides (NO) are produced using ammonia or urea to form an oxide catalyst that is blended with H-zeolite or a zeolite that can be converted to H-zeolite, including an oxide or mixed oxide support, optionally impregnated with a metal oxide dopant. x Disclosed herein are catalyst compositions for treating exhaust gases containing NO. The disclosure also relates to processes for making such catalyst compositions, and methods for treating NO. x The present invention relates to processes and methods for reducing the formation of

Description

[Technical field]

[0001] This application claims the benefit of priority to European Patent Application No. 21212603.1, filed December 6, 2021, the contents of which are incorporated herein by reference in their entirety.

[0002] The present disclosure relates to a catalyst composition comprising an H-zeolite, or a zeolite that can be converted to an H-zeolite, and an oxide-based catalyst, and a method for producing nitrogen oxides, NO, using NH3 or urea, for example, for diesel applications. x The present disclosure is directed to a process for selective catalytic reduction (SCR) of NH3. The present disclosure also relates to an effective approach for improving the catalytic performance of oxide-based NH3-SCR catalysts.

[0003] Nitric oxide (NO) such as nitric oxide (NO) and nitrogen dioxide (NO2) x ), when released into the atmosphere, are some of the major contributing factors to undesirable environmental effects such as smog. Due to the harmful effects of these gases, most government authorities have restricted industrial emissions in an attempt to limit their atmospheric levels. For example, worldwide regulations mandate lower emissions from vehicles.

[0004] Treats exhaust gas and NO x The use of zeolite-based catalysts together with reducing agents such as ammonia or urea to reduce gases to elemental nitrogen and water vapor is a well-established procedure, commonly referred to as selective catalytic reduction (SCR).

[0005] Cu-zeolite is generally used for NOx reduction in diesel vehicles. x Although it is the most active type of catalyst for the reduction of NO, its activity is not high enough below about 200 °C. At low temperatures, Cu-zeolite catalysts also x It needs to be saturated with NH3 before it can be effective for reduction. This slows down the response to urea injection. Furthermore, in terms of cost, Cu-CHA is one of the most expensive catalysts to manufacture.

[0006] V2O5 / TiO2 based catalysts require lower NH3 loadings but are much less active at low temperatures. Furthermore, the use of V2O5 and its possible leakage into the environment are environmental concerns.

[0007] Therefore, at low temperatures (below about 200°C), x Efficient removal of is an unmet need and a major challenge for the automotive emissions industry.

[0008] This disclosure relates to oxide-based SCR catalysts. x The present applicants have surprisingly found that by physically blending a small amount of H-zeolite or a zeolite that can be converted to H-zeolite with an oxide-based catalyst to form a catalyst composition, the conversion rate is increased and NO formation is reduced compared to the oxide-based catalyst. x It has been found that this results in a significant increase in conversion and a decrease in N2O formation, and the effect appears to be synergistic, i.e. the activity of the blended catalyst is greater than the sum of the individual components.

[0009] This effect has been demonstrated to be effective for several types of zeolites as well as many oxide and mixed oxide materials, and works for both powder and coated monolith catalysts.

[0010] The catalyst system of the present disclosure is also suitable for high load applications deployed in close-coupled locations and provides a cost-effective solution for reducing NO from diesel engines at low temperatures. x Address the challenge of effectively controlling emissions.

[0011] The present disclosure relates to a method for producing NO using ammonia or urea. xThe present invention provides a catalyst composition for treating exhaust gases comprising: a) a catalyst composition comprising an oxide or mixed oxide support impregnated with a metal oxide dopant to form an oxide catalyst; b) a catalyst composition comprising an oxide or mixed oxide support impregnated with a metal oxide dopant to form an oxide catalyst; c) a catalyst composition comprising an oxide catalyst comprising an H-zeolite or a zeolite that can be converted to an H-zeolite; and d) a catalyst composition comprising an oxide catalyst comprising an oxide catalyst; and d) a catalyst composition comprising an oxide catalyst;

[0012] The oxide or mixed oxide support of the catalyst composition is selected from MnO2 / ZrO2, WO3 / TiO2, WO3 / Al2O3, SiO2 / Al2O3, Ce / Zr / La, Ce / Zr / La / Y, CeO2, CeO2 / Al2O3, and combinations thereof. The metal oxide dopant of the catalyst composition is selected from MnO2, CeO2, Nb2O5, CuO, and combinations thereof. The H-zeolite catalyst of the catalyst composition, or a zeolite that can be converted to an H-zeolite, is selected from structures including BEA, FER, MOR, MFI, FAU, CHA, and combinations thereof.

[0013] The H-zeolite, or a zeolite that can be converted to an H-zeolite, comprises about 5% to about 50% by weight of the oxide catalyst. The metal dopant comprises about 1% to about 20% by weight of the oxide catalyst. The oxide or mixed oxide support is about 20% CeO2 / Al2O3. The metal oxide dopant is about 5% by weight MnO2. The H-zeolite structure, or a zeolite that can be converted to an H-zeolite, is about 20% by weight BEA. The oxide or mixed oxide support is about 18% MnO2 / ZrO2. The H-zeolite structure, or a zeolite structure that can be converted to an H-zeolite structure, is about 20% by weight BEA.

[0014] The catalyst composition of the present disclosure is in a form selected from a powder and a coated monolith.

[0015] The present disclosure also provides a process for preparing a catalyst composition. The process includes disposing one or more oxide dopants on an oxide or mixed oxide support using an incipient wetness technique or by precipitation to form an oxide catalyst. The oxide catalyst is physically blended in a slurry with an H-zeolite or with a zeolite that can be converted to an H-zeolite to form a blend. The blend is calcined at a temperature of at least about 450° C. for about 1 hour to obtain the catalyst composition.

[0016] The present disclosure also provides a method for determining whether NO in exhaust gases x The present invention provides a process for reducing the formation of catalytic compounds of the present disclosure, comprising contacting an exhaust gas stream with a catalytic composition of the present disclosure in the presence of a reducing agent. The process has a temperature of about 250° C. or less. The process has a temperature of about 200° C. A catalytic article is also provided that includes a substrate having a plurality of channels for a gas stream and a catalytic composition of the present disclosure disposed thereon.

[0017] This disclosure is based on the x Further provided is a method for treating an exhaust gas containing NO. The method comprises contacting the exhaust gas with a catalyst article of the present disclosure at a temperature ranging from about 200° C. to about 250° C. or higher for a period of time. The method is used in high load applications in a close-coupled location. x The conversion level is at least about 18% higher at about 250° C. than the catalyst composition not blended with H-zeolite or a zeolite that can be converted to H-zeolite. The formation of NO at about 250° C. is at least about 5 times lower than the catalyst composition not blended with H-zeolite or a zeolite that can be converted to H-zeolite.

[0018] Also provided herein is an emission treatment system for treating an exhaust gas stream. The emission treatment system includes an engine generating an exhaust gas stream and a catalytic article of the present disclosure disposed downstream of the engine and in fluid communication with the exhaust gas stream. The emission treatment system may include any of a variety of catalysts, including diesel oxidation catalysts (DOC), catalyzed soot filters (CSF), soot filters, ammonia oxidation (AMO), and the like. x) Catalyst, Lean NO x The system may further include one or more of a liquid nitrogen trap (LNT) and a nitrogen-based reductant injector. [Brief description of the drawings]

[0019] [Figure 1] FIG. 1 is a graph showing a comparison of catalytic performance between 2 g / in3 of 8%Nb2O5 / 1%CuO / CeO2 (Monolith Sample 1) and 1.6 g / in3 of 8%Nb2O5 / 1%CuO / CeO2+0.4 g / in3 H-CHA (Monolith Sample 2) coated monolith catalyst for NOx conversion. [Diagram 2] FIG. 1 is a graph showing a comparison of catalytic performance between 2 g / in3 of 8%Nb2O5 / 1%CuO / CeO2 (Monolith Sample 1) and 1.6 g / in3 of 8%Nb2O5 / 1%CuO / CeO2+0.4 g / in3 H-CHA (Monolith Sample 2) coated monolith catalyst for N2O conversion. [Diagram 3] 1 is a graph showing a comparison of fresh catalyst performance between 2 g / in 36.6 wt% MnO2 / 3.4 wt% TiO2 / 90 wt% CeO2 / Al2O3 (Monolith Sample 3) and 2 g / in 36.6 wt% MnO2 / 3.4 wt% TiO2 / 90 wt% CeO2 / Al2O3 + 0.4 g / in 3 H-Beta (Monolith Sample 4). [Figure 4] 13 is a graph showing a comparison of aged catalyst performance between 2 g / in3 of 6.6 wt% MnO2 / 3.4 wt% TiO2 / 90 wt% CeO2 / Al2O3 (Monolith Sample 3) and 2 g / in3 of 6.6 wt% MnO2 / 3.4 wt% TiO2 / 90 wt% CeO2 / Al2O3 + 0.4 g / in3 H-Beta (Monolith Sample 4).

[0020] As used herein, "a" or "an" entity refers to one or more of that entity; for example, "a vessel" refers to one or more vessels or at least one vessel unless otherwise specified. Thus, the terms "a" (or "an"), "one or more," and "at least one" are used interchangeably herein.

[0021] As used herein, the term "about" means approximately, in the region of, roughly, or around. When the term "about" is used in conjunction with a numerical range, it modifies that range by extending the boundaries above and below the numerical values ​​set forth. In general, the term "about" is used herein to modify numerical values ​​above and below the set forth value with a variance of 10%.

[0022] The following explanation uses ammonia or urea to produce NO x Various embodiments of different aspects of the disclosed compositions, as well as methods and processes, are provided for catalytic compositions for treating exhaust gases comprising:

[0023] In some embodiments, the catalyst composition includes an oxide or mixed oxide support impregnated with a metal oxide dopant to form an oxide catalyst. In some embodiments, the oxide catalyst is mixed with an H-zeolite. In some embodiments, the oxide catalyst is mixed with a zeolite that can be converted to an H-zeolite. In some embodiments, the oxide or mixed oxide support is mixed with an H-zeolite. In some embodiments, the oxide catalyst or mixed oxide support is mixed with a zeolite that can be converted to an H-zeolite. In some embodiments, the H-zeolite and the oxide catalyst are blended. In some embodiments, the zeolite that can be converted to an H-zeolite and the oxide catalyst are blended. In some embodiments, the H-zeolite and the oxide or mixed oxide support are blended. In some embodiments, the zeolite that can be converted to an H-zeolite and the oxide or mixed oxide support are blended.

[0024] In some embodiments, the oxide or mixed oxide support is selected from MnO2 / ZrO2, WO3 / TiO2, WO3 / Al2O3, SiO2 / Al2O3, Ce / Zr / La, Ce / Zr / La / Y, CeO2, CeO2 / Al2O3, and combinations thereof. In some embodiments, the oxide or mixed oxide support is MnO2 / ZrO2. In some embodiments, the oxide or mixed oxide support is WO3 / TiO2. In some embodiments, the oxide or mixed oxide support is WO3 / Al2O3. In some embodiments, the oxide or mixed oxide support is SiO2 / Al2O3. In some embodiments, the oxide or mixed oxide support is Ce / Zr / La. In some embodiments, the oxide or mixed oxide support is Ce / Zr / La / Y. In some embodiments, the oxide or mixed oxide support is CeO2. In some embodiments, the oxide or mixed oxide support is CeO2 / Al2O3.

[0025] In some embodiments, the oxide or mixed oxide support is about 5% CeO2 / Al2O3. In some embodiments, the oxide or mixed oxide support is about 10% CeO2 / Al2O3. In some embodiments, the oxide or mixed oxide support is about 15% CeO2 / Al2O3. In some embodiments, the oxide or mixed oxide support is about 5% MnO2 / ZrO2. In some embodiments, the oxide or mixed oxide support is about 10% MnO2 / ZrO2. In some embodiments, the oxide or mixed oxide support is about 18% MnO2 / ZrO2. In some embodiments, the oxide or mixed oxide support is about 20% MnO2 / ZrO2.

[0026] In some embodiments, the metal oxide dopant is selected from MnO2, CeO2, Nb2O5, CuO, and combinations thereof. In some embodiments, the metal oxide dopant is MnO2. In some embodiments, the metal oxide dopant is CeO2. In some embodiments, the metal oxide dopant is Nb2O5. In some embodiments, the metal oxide dopant is CuO.

[0027] In some embodiments, the metal dopant comprises about 1% to about 20% by weight of the oxide catalyst. In some embodiments, the metal dopant comprises about 2% to about 10% by weight of the oxide catalyst. In some embodiments, the metal dopant comprises about 5% by weight of the oxide catalyst.

[0028] In some embodiments, the metal oxide dopant is about 5% MnO2 by weight of the oxide catalyst. In some embodiments, the metal oxide dopant is about 5% CeO2 by weight of the oxide catalyst. In some embodiments, the metal oxide dopant is about 5% Nb2O5 by weight of the oxide catalyst. In some embodiments, the metal oxide dopant is about 5% CuO by weight of the oxide catalyst. In some embodiments, the metal oxide dopant is about 10% MnO2 by weight of the oxide catalyst. In some embodiments, the metal oxide dopant is about 10% CeO2 by weight of the oxide catalyst. In some embodiments, the metal oxide dopant is about 10% Nb2O5 by weight of the oxide catalyst. In some embodiments, the metal oxide dopant is about 10% CuO by weight of the oxide catalyst.

[0029] In some embodiments, the zeolite is an H-zeolite. In some embodiments, the zeolite is selected from zeolites that can be converted to H-zeolites. In some embodiments, the zeolite is an NH4-zeolite that can be converted to H-zeolite. In some embodiments, the NH4-zeolite is converted to H-zeolite by calcination. In some embodiments, the H-zeolite, or a zeolite that can be converted to H-zeolite, has or can have greater than about 95% exchangeable sites as H. In some embodiments, the H-zeolite, or a zeolite that can be converted to H-zeolite, has or can have greater than about 90% exchangeable sites as H. In some embodiments, the H-zeolite, or a zeolite that can be converted to H-zeolite, has or can have greater than about 85% exchangeable sites as H.

[0030] In some embodiments, the H-zeolite or zeolite that can be converted to an H-zeolite is selected from structures including BEA, FER, MOR, MFI, FAU, CHA, and combinations thereof. In some embodiments, the H-zeolite structure or zeolite structure that can be converted to an H-zeolite structure includes BEA. In some embodiments, the H-zeolite structure or zeolite structure that can be converted to an H-zeolite structure includes FER. In some embodiments, the H-zeolite structure or zeolite structure that can be converted to an H-zeolite structure includes MOR. In some embodiments, the H-zeolite structure or zeolite structure that can be converted to an H-zeolite structure includes MFI. In some embodiments, the H-zeolite structure or zeolite structure that can be converted to an H-zeolite structure includes FAU. In some embodiments, the H-zeolite structure or zeolite structure that can be converted to an H-zeolite structure includes CHA.

[0031] In some embodiments, the H-zeolite or zeolite that can be converted to H-zeolite comprises about 5% to about 50% by weight of the oxide catalyst. In some embodiments, the H-zeolite or zeolite that can be converted to H-zeolite comprises about 10% to about 40% by weight of the oxide catalyst. In some embodiments, the H-zeolite or zeolite that can be converted to H-zeolite comprises about 20% to about 30% by weight of the oxide catalyst. In some embodiments, the H-zeolite or zeolite that can be converted to H-zeolite comprises about 5% by weight of the oxide catalyst. In some embodiments, the H-zeolite or zeolite that can be converted to H-zeolite comprises about 10% by weight of the oxide catalyst. In some embodiments, the H-zeolite or zeolite that can be converted to H-zeolite comprises about 15% by weight of the oxide catalyst. In some embodiments, the H-zeolite or zeolite that can be converted to H-zeolite comprises about 20% by weight of the oxide catalyst. In some embodiments, the H-zeolite or zeolite that can be converted to H-zeolite comprises about 25% by weight of the oxide catalyst. In some embodiments, the H-zeolite or zeolite that can be converted to H-zeolite comprises about 30% by weight of the oxide catalyst. In some embodiments, the H-zeolite or zeolite that can be converted to H-zeolite comprises about 35% by weight of the oxide catalyst. In some embodiments, the H-zeolite or zeolite that can be converted to H-zeolite comprises about 40% by weight of the oxide catalyst. In some embodiments, the H-zeolite or zeolite that can be converted to H-zeolite comprises about 45% by weight of the oxide catalyst. In some embodiments, the H-zeolite or zeolite that can be converted to H-zeolite comprises about 50% by weight of the oxide catalyst.

[0032] In some embodiments, the H-zeolite structure or the zeolite structure that can be converted to the H-zeolite structure is about 10% BEA by weight of the oxide catalyst. In some embodiments, the H-zeolite structure or the zeolite structure that can be converted to the H-zeolite structure is about 10% FER by weight of the oxide catalyst. In some embodiments, the H-zeolite structure or the zeolite structure that can be converted to the H-zeolite structure is about 10% MOR by weight of the oxide catalyst. In some embodiments, the H-zeolite structure or the zeolite structure that can be converted to the H-zeolite structure is about 10% MFI by weight of the oxide catalyst. In some embodiments, the H-zeolite structure or the zeolite structure that can be converted to the H-zeolite structure is about 10% FAU by weight. In some embodiments, the H-zeolite structure or the zeolite structure that can be converted to the H-zeolite structure is about 10% CHA by weight of the oxide catalyst. In some embodiments, the H-zeolite structure or the zeolite structure that can be converted to the H-zeolite structure is about 20% BEA by weight of the oxide catalyst. In some embodiments, the H-zeolite structure or the zeolite structure that can be converted to the H-zeolite structure is about 20% FER by weight of the oxide catalyst. In some embodiments, the H-zeolite structure or the zeolite structure that can be converted to the H-zeolite structure is about 20% MOR by weight of the oxide catalyst. In some embodiments, the H-zeolite structure or the zeolite structure that can be converted to the H-zeolite structure is about 20% MFI by weight of the oxide catalyst. In some embodiments, the H-zeolite structure or the zeolite structure that can be converted to the H-zeolite structure is about 20% FAU by weight. In some embodiments, the H-zeolite structure or the zeolite structure that can be converted to the H-zeolite structure is about 20% CHA by weight of the oxide catalyst.

[0033] In some embodiments, the catalyst composition is a powder. In some embodiments, the catalyst composition is a coated monolith.

[0034] In some embodiments, a process for making a catalyst composition is provided. In some embodiments, the process includes impregnating one or more oxide dopants onto an oxide or mixed oxide support using an incipient wetness technique to form an oxide catalyst. In some embodiments, the process includes disposing one or more oxide dopants on the oxide or mixed oxide support by precipitating a dopant precursor in a liquid solution to form an oxide catalyst. In some embodiments, the process further includes physically blending an H-zeolite with the oxide catalyst in a slurry state to form a blend. In some embodiments, the process further includes physically blending a zeolite that can be converted to an H-zeolite with the oxide catalyst in a slurry state to form a blend. In some embodiments, the process further includes calcining the blend at a temperature of at least about 450° C. for about 1 hour to obtain the catalyst composition.

[0035] In some embodiments, NO in the exhaust gas x In some embodiments, the process includes contacting an exhaust gas stream with a catalyst composition of the present disclosure in the presence of a reducing agent, such as a urea solution or gaseous ammonia.

[0036] In some embodiments, the process temperature is about 250° C. or less. In some embodiments, the process temperature is about 250° C. In some embodiments, the process temperature is about 240° C. In some embodiments, the process temperature is about 230° C. In some embodiments, the process temperature is about 220° C. In some embodiments, the process temperature is about 210° C. In some embodiments, the process temperature is about 200° C.

[0037] In some embodiments, a catalytic article is provided that comprises a substrate having a plurality of channels for gas flow and a catalytic composition of the present disclosure disposed thereon.

[0038] In some embodiments, NO x A method of treating an exhaust gas comprising: (a) contacting the exhaust gas with a catalytic article of the present disclosure for a period of time at a temperature ranging from about 200° C. to about 250° C. or greater; in some embodiments, the temperature is about 200° C.; in some embodiments, the temperature is about 210° C.; in some embodiments, the temperature is about 220° C.; in some embodiments, the temperature is about 230° C.; in some embodiments, the temperature is about 240° C.; in some embodiments, the temperature is about 250° C.; and in some embodiments, the temperature is greater than about 250° C.

[0039] In some embodiments, the catalytic articles of the present disclosure can be used to reduce NOx in high load applications deployed in close-coupled locations. x A method for treating an exhaust gas comprising:

[0040] In some embodiments, NO in exhaust gas at about 250° C. using the catalyst of the present disclosure. x The conversion level is at least about 18% higher than the catalyst composition in which the H-zeolite or the zeolite that can be converted to H-zeolite is not blended. In some embodiments, NO x The conversion level is at least about 18% higher. x The conversion level is at least about 20% higher. x The conversion level is at least about 25% higher. x The conversion level is at least about 30% higher. x The conversion level is at least about 34% higher.

[0041] In some embodiments, the formation of N2O at about 250° C. is at least about 5 times lower than the catalyst composition without the blended H-zeolite or zeolite that can be converted to H-zeolite.

[0042] In some embodiments, an emission treatment system for treating an exhaust gas stream is provided, hi some embodiments, the emission treatment system comprises an engine generating an exhaust gas stream and a catalytic article of the present disclosure disposed downstream of the engine in fluid communication with the exhaust gas stream.

[0043] In some embodiments, the emission treatment system includes a diesel oxidation catalyst (DOC), a catalyzed soot filter (CSF), a soot filter, an ammonia oxidation (AMO) x ) Catalyst, Lean NO x In some embodiments, the emission treatment system further comprises one or more of a diesel oxidation catalyst (DOC). In some embodiments, the emission treatment system further comprises a catalyzed soot filter (CSF). In some embodiments, the emission treatment system further comprises a soot filter. In some embodiments, the emission treatment system further comprises an ammonia oxidation (AMO x In some embodiments, the emission treatment system further comprises a lean NO 2 catalyst. x trap (LNT).In some embodiments, the emissions treatment system further comprises a nitrogen based reductant injector.

[0044] Unless indicated to the contrary or clear from the context, a claim or specification condition containing "or" or "and / or" between at least one member of a group is deemed satisfied when one, more than one, or all of the members of a group are present in, used in, or otherwise relevant to a given product, process, or system. The disclosure includes embodiments in which exactly one group member is present in, used in, or otherwise relevant to a given product, process, or system. The disclosure includes embodiments in which more than one or all of the members of a group are present in, used in, or otherwise relevant to a given product, process, or system.

[0045] Furthermore, the disclosure encompasses all variations, combinations, and permutations in which at least one limitation, element, clause, or descriptive term from at least one of the enumerated claims is introduced into another claim. For example, any claim that is dependent on another claim may be modified to include at least one limitation found in any other claim that is dependent on the same independent claim. When elements are presented as a list, such as in Markush group format, each subgroup of elements is also disclosed, and any element(s) can be removed from the group. In general, when the disclosure or aspects of the disclosure are referred to as including certain elements and / or features, it should be understood that embodiments of the disclosure or aspects of the disclosure consist of or consist essentially of such elements and / or features. For the sake of brevity, these embodiments have not been specifically described in this language herein. When ranges are given, the endpoints are included. Furthermore, unless otherwise indicated or clear from the context and understanding of one of ordinary skill in the art, values ​​expressed as ranges can assume any particular value or subrange within the stated range in different embodiments of the disclosure, unless the context clearly indicates otherwise.

[0046] Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments of the disclosure described herein which equivalents are intended to be encompassed by the claims.

[0047] Before describing example embodiments of the present disclosure, it is to be understood that the disclosure is not limited to the details of construction or process steps set forth in the following examples, and that other embodiments are possible and that they may be practiced or carried out in various ways. EXAMPLES

[0048] The following examples are intended to be illustrative and are not meant to limit the scope of the disclosure in any way.

[0049] Preparation of powder catalyst Oxide Catalyst Oxide-based catalysts were prepared by impregnating one or more oxides (doped oxides) onto an oxide or mixed oxide support.

[0050] For the Nb-free oxide catalysts (samples 1, 2, 7, and 8), the metal oxides were co-impregnated onto the support by using mixed metal salt solutions. For example, sample 1 was prepared by co-impregnating Mn / Ce nitrate solution onto 5% WO3 / TiO2 support using the incipient wetness technique. After impregnation, the samples were calcined at 500°C in air for 2 hours.

[0051] For Nb-containing catalysts (samples 3-6, 9, and 10), sequential impregnation was used with Nb impregnation as the second step. For example, sample 3 was prepared by first impregnating Mn nitrate onto a 50% CeO2 / Al2O3 support, followed by calcination at 500 °C in air for 2 h. The resulting material was further impregnated with ammonium niobate(V) oxalate solution. After the second impregnation, the resulting powder was again calcined at 500 °C in air for 2 h.

[0052] Oxide / zeolite mixed catalysts Additional zeolite component is added to the oxide component at the slurry stage (see sample preparation). The amount of zeolite is 10%, 20%, 30%, or 50% of the oxide catalyst.

[0053] Sample Forming To prepare powder catalyst suitable for reactor evaluation, the oxide catalyst or oxide + zeolite was suspended in deionized water at about 30% solids. Aluminum binder (about 5 wt%) was added to the slurry. The catalyst slurry was dried by stirring at 100 °C and then calcined at 550 °C for 1 h. The resulting material was crushed and sieved into a fraction of 250-500 mm. The catalyst thus obtained is referred to as "fresh" catalyst.

[0054] Catalyst Identification and Composition Table 1 summarizes the catalyst composition of the Group I samples. This matrix is ​​designed to examine the effect of zeolite addition on various catalyst compositions. The oxide and mixed oxide supports were obtained commercially from various suppliers. The concentration of doped oxides is expressed as weight percent of the total oxide catalyst. The amount of zeolite is an additional 20 weight percent of the oxide catalyst. All zeolites were initially in the ammonium form, but were converted to the hydrogen form by calcination at 450°C for 5 hours before mixing with the oxide catalyst. BEA is zeolite beta with a SiO2 / Al2O3 ratio of 25. FER is ferrierite with a SiO2 / Al2O3 ratio of 20.

[0055] [Table 1]

[0056] Table 2 summarizes the catalyst composition of Group II samples designed to investigate the effect of zeolite addition as a function of zeolite structure. The oxide catalyst component (sample 2) is 5% MnO2 supported on 20% CeO2 / Al2O3. The amount of zeolite is an additional 20 wt% of the oxide catalyst. All zeolites are in the hydrogen form. BEA is zeolite beta with SiO2 / Al2O3 ratio of 25. FER is ferrierite with SiO2 / Al2O3 ratio of 20. MOR is mordenite with SiO2 / Al2O3 ratio of 20. MFI is ZSM-5 with SiO2 / Al2O3 ratio of 30. FAU is zeolite Y with SiO2 / Al2O3 ratio of 30. CHA is chabazite with SiO2 / Al2O3 ratio of 24.

[0057] [Table 2]

[0058] Table 3 summarizes the catalyst composition of the group III samples designed to investigate the effect of zeolite addition as a function of zeolite structure with the oxide catalyst component (sample 11) being 18% MnO2 / ZrO2. The amount of zeolite is an additional 20 wt% of the oxide catalyst. The zeolite used in this group is the same as in group II.

[0059] [Table 3]

[0060] Table 4 summarizes the catalyst compositions of Group IV samples designed to investigate the effect of zeolite addition as a function of zeolite amount. Two oxide compositions, sample 2 (5% MnO2 supported on 20% CeO2 / Al2O3) and sample 11 (18% MnO2 / ZrO2), are used as base catalysts. The zeolite is BEA (zeolite beta) and the zeolite is added to the oxide catalyst as an additional 10%, 20%, 30%, or 50% by weight of the oxide catalyst.

[0061] [Table 4]

[0062] Preparation of monolith samples Monolith sample 1 (Nb2O5 / CuO / CeO2): CuO / CeO2 powder was first prepared by impregnating Cu solution onto CeO2. The Cu solution was 0.5M Cu(NH3)4(NO3)2 solution prepared by adding 25% NH3·H2O to Cu(NO3)2 solution with a molar ratio of NH3 / Cu of 8. The Cu solution was impregnated onto CeO2 powder using incipient wetness technique to reach a CuO loading of 1.09 wt% after calcination. The resulting powder was dried at 110 °C for 4 h and then calcined at 550 °C for 2 h with a ramp rate of 5 °C / min. The CuO / CeO2 powder was further impregnated with Nb solution (1M C4H4NNbO9) to reach a final composition of 8% Nb2O5 and 1% CuO on CeO2. The Nb2O5 / CuO / CeO2 powder was dried again at 110 °C for 4 h and then calcined at 550 °C for 2 h with a ramp rate of 5 °C / min.

[0063] The Nb2O5 / CuO / CeO2 powders were mixed with Zr acetate binder (0.1 g / in 3 ) and alumina binder (0.2g / in 3 A washcoat slurry was prepared by adding 100% ZnO and 100% ZnO to deionized water with stirring. The slurry was then milled to 90% particles <16 μm (D90<16 μm). The slurry was coated onto a small monolith core (13 cells × 13 cells × 3” length) at a pH of 3.5–4.5. The coated samples were dried at 110 °C for 2 h and calcined at 450 °C for 1 h (fresh samples). The oxide washcoat loading was 2 g / in 3 It is.

[0064] Monolith sample 2 (Nb2O5 / CuO / CeO2+20%H-CHA): The same oxide powder was used for monolith sample 2. In addition, H-type chabazite zeolite was added to the slurry. The oxide washcoat loading was 1.6 g / in 3 and the zeolite washcoat loading was 0.4 g / in 3 Therefore, the total washcoat loadings of Monolith Sample 1 and Monolith Sample 2 are the same.

[0065] Monolith sample 3 (MnO2 / TiO2 / CeO2 / Al2O3): Powder samples (MnO2 / TiO2 / CeO2 / Al2O3) were first prepared by co-impregnating Mn-Ti solution onto a commercial CeO2 / Al2O3 (20% CeO2) support. The Mn-Ti solution was prepared by first dissolving Mn(NO3)2·4H2O in ethanol and then adding tetrabutyl titanate to the Mn solution. The Mn-Ti solution was impregnated onto the CeO2 / Al2O3 support using the incipient wetness technique. The resulting powder was dried at 100 °C for 1 h and calcined at 500 °C for 2 h. The calcined powder has a composition of 6.6 wt% MnO2, 3.4 wt% TiO2, and 90 wt% CeO2 / Al2O3.

[0066] MnO2 / TiO2 / CeO2 / Al2O3 powders were mixed with an alumina binder (0.1 g / in 3 The washcoat slurry was prepared by adding 100% cellulose acetate to deionized water with stirring. The slurry was then mixed with 100% cellulose acetate and 100% cellulose acetate with 90% particles <12 μm (D 90 The slurry was coated onto small monolith cores (13 cells × 13 cells × 3” length) at pH 4.5–5.5. The coated samples were dried at 110 °C for 2 h and calcined at 450 °C for 1 h (fresh samples). The oxide washcoat loading was 2 g / in 3 It is.

[0067] Monolith sample 4 (MnO2 / TiO2 / CeO2 / Al2O3+20%H-Beta): The same oxide powder was used for monolith sample 4. In addition, H-type beta zeolite was added to the slurry. The oxide washcoat loading was 2 g / in 3 and the zeolite washcoat loading was 0.4 g / in 3 It is.

[0068] Catalyst Aging The catalyst was aged at 650° C. for 50 hours in 10% water vapor in air.

[0069] Catalyst Testing Procedure Test procedure for powder samples Fresh and aged catalysts were tested in a high throughput reactor with a feed of 500 ppm NO, 500 ppm NH, 5% H2O, 10% O2, balance N2. For the oxide and oxide / zeolite catalysts, 120 mg and 144 mg samples were used, respectively. The samples were diluted to a volume of 1 mL with corundum, which is 2 g / in 3 80,000h assuming washcoat loading of -1 This corresponds to a simulated monolith space velocity of 175°C. Activity was evaluated at constant temperatures of 175°C, 200°C, 225°C, 250°C, 300°C, 400°C, 550°C, and 575°C.

[0070] Monolith sample testing procedure: The monolith samples were run in a monolith reactor for 80,000 h using a feed consisting of 500 ppm NO, 500 ppm NH, 5% H2O, 10% O2, 5% CO2, and balance N2. -1 The monolith space velocity was tested at 125°C, 150°C, 175°C, 200°C, 225°C, 250°C, 300°C, 400°C, and 450°C.

[0071] Test results Powder samples: Table 5 shows the test results (NO xThe results of the experiments are summarized in Table 1. The addition of a small amount of zeolite (beta or ferrierite) to the oxide catalysts reduced NO conversion and NO formation at all temperatures compared to the oxide catalysts (samples 1-11). x The conversion rate increases substantially. This activity improvement was observed for all catalyst compositions (Samples 1-11). At the same time, the addition of zeolite results in lower N2O formation over most catalysts, especially for the high N2O producing oxide catalysts. For example, when beta zeolite is added to Sample 4 (Sample 4A), the N2O formation decreases from 8 ppm, 22 ppm, 91 ppm, and 203 ppm to 4 ppm, 9 ppm, 26 ppm, and 78 ppm at 200°C, 250°C, 300°C, and 400°C, respectively. The effect on N2O reduction is even more pronounced for Sample 11 (98 ppm N2O on Sample 11 vs. 5 ppm on Sample 11A at 300°C). The performance of the zeolite materials was also examined. Both BEA and FER showed NO near baseline levels, especially at temperatures below 300°C. x Therefore, NO conversion on the zeolite-containing catalyst x The increased conversion and reduced N2O formation are due to the synergistic interactions between the oxide and zeolite components.

[0072] [Table 5]

[0073] Table 6 shows the test results (NO x The results of the experiments are summarized in Table 1. In general, aging of the catalyst reduces the benefit of the zeolite addition, and the extent of the reduction depends on the catalyst system. For some catalysts (samples 3, 4, 7, 8, 9, and 10), the NO xThere is a significant activity enhancement at high temperatures, with little or no conversion benefit. For the other catalysts (samples 2 and 11), significant activity improvements were observed at both low and high temperatures. For N2O formation, the aged catalyst still shows the beneficial effect of zeolite addition on N2O reduction. For aged sample 11, zeolite addition reduced the NO x It shows a significant effect in increasing the conversion rate and reducing N2O formation.

[0074] [Table 6]

[0075] Table 7 summarizes the fresh results for the Group II samples. The addition of 20% zeolite of any structure (BEA, FER, MOR, MFI, FAU, or CHA) significantly increased NO2 production compared to the base catalyst (Sample 2: 5% MnO2 on 20% CeO2 / Al2O3) at any temperature. x The conversion is significantly increased. The improvement in activity is especially noticeable at low temperatures (200°C and 250°C). In general, the zeolite-containing catalysts produce no N2O at 200°C and 250°C, and produce less N2O at 300°C and 400°C compared to the base catalyst.

[0076] [Table 7]

[0077] Table 8 summarizes the aging results of the Group II samples. After aging, in general, the advantage of containing zeolite is diminished. The most active catalyst is Sample 2F (Sample 2+20% CHA), whose conversion is about twice that of the base catalyst at 200°C and 250°C. N2O formation over the aged catalyst is still lower than that over the base catalyst at lower temperatures.

[0078] [Table 8]

[0079] Table 9 summarizes the fresh results for the Group III samples. NO over zeolite-containing catalysts x The conversion is 2-4 times higher than the base catalyst (sample 11: 18% MnO2 / ZrO2) at all temperatures. N2O formation over the zeolite-containing catalysts is also much lower compared to the base catalyst, especially at 300 and 400 °C.

[0080] [Table 9]

[0081] Table 10 summarizes the aging results for the Group III samples. The effect of zeolite is largely maintained after aging. NO at 250°C x The conversion is 18%-34% higher over the zeolite-containing catalysts (58%-74%) than over the base catalyst (40%). Sample 11F (Sample 11+20% CHA) is the most active aged catalyst in this group. All zeolite-containing catalysts produce much lower N2O at all temperatures.

[0082] [Table 10]

[0083] Table 11 shows the effect of zeolite (BEA) amount on fresh performance based on Sample 2 and Sample 11. For Sample 2, the addition of 10% zeolite reduced NO x The conversion rate increases dramatically. However, changing the amount of zeolite between 10% and 50% does not seem to make a significant difference in this effect. For sample 11, the addition of 10% zeolite more than triples the NO conversion at 200°C and 250°C. x The conversion further increases with increasing zeolite amount at 200° C. but plateaus at higher temperatures. No N2O was detected over all zeolite-containing catalysts at 200° C. and 250° C., and very little N2O was detected at 300° C. and 400° C.

[0084] [Table 11]

[0085] Table 12 shows the effect of zeolite (BEA) amount on the aging performance based on Sample 2 and Sample 11. For Sample 2, the addition of 10% to 30% zeolite is almost indistinguishable in terms of zeolite effect. Adding 50% zeolite seems to have a slight disadvantage at 200°C. For Sample 11, unlike the fresh catalyst, adding 10% zeolite increases NO at 250°C compared to (20%, 30%, and 50%). x The conversion is the highest. All zeolite-containing samples produce less N2O compared to their base catalysts (sample 2 or sample 11).

[0086] [Table 12]

[0087] Monolith sample: Figures 1 and 2 show the effect of blending H-zeolite (H-CHA) on the SCR performance of Nb / Cu-based (8Nb / 1Cu / CeO2) coated monolith catalyst. The catalyst had a GHSV of 80000h -1 It was tested fresh in a laboratory reactor with a feed containing 500 ppm NO, 500 ppm NH, 5% H, O, 5% CO, 10% O, and balance N.

[0088] Monolith sample 2 (H-CHA-containing sample) produced much higher NO x The conversion and lower N2O formation are shown in Figure 1. This beneficial effect is especially evident at higher reaction temperatures. There is also a clear reduction in N2O formation (Figure 2).

[0089] 3 and 4 show the SCR performance of fresh monolith Sample 3 and aged monolith Sample 4. Monolith Sample 4 (H-Beta containing sample) showed significantly lower NO 3 emissions compared to Monolith Sample 3 over the entire temperature range tested. x The two aged catalysts are more active in terms of conversion (Figure 3, solid line). NO formation is low (less than 20 ppm at 450 °C) on monolith sample 4, whereas it is about 90 ppm on monolith sample 3 (Figure 3, dotted line). These two aged catalysts have comparable NO formation at temperatures below 300 °C. x The conversion, but above 300° C. aged monolith Sample 4 has much higher SCR activity (FIG. 4, solid line). The aged monolith Sample 4 continues to show significant benefits in reducing NO formation (FIG. 4, dotted line).

[0090] Embodiment 1. NO using ammonia or urea x A catalytic composition for treating an exhaust gas comprising: A catalyst composition comprising an oxide or mixed oxide support impregnated with a metal oxide dopant to form an oxide catalyst, and comprising an H-zeolite. 2. NO using ammonia or urea x A catalytic composition for treating an exhaust gas comprising: A catalyst composition comprising an oxide or mixed oxide support, including a zeolite that can be impregnated with a metal oxide dopant to form an oxide catalyst, and converted to an H-zeolite. 3. The catalyst composition of embodiment 1, wherein the H-zeolite and the oxide catalyst are blended. 4. The catalyst composition of embodiment 2, wherein a zeolite that can be converted to a H-zeolite is blended with an oxide catalyst. 5. The catalyst composition according to any one of the preceding embodiments, wherein the oxide or mixed oxide support is selected from MnO2 / ZrO2, WO3 / TiO2, WO3 / Al2O3, SiO2 / Al2O3, Ce / Zr / La, Ce / Zr / La / Y, CeO2, CeO2 / Al2O3, and combinations thereof. 6. The catalyst composition according to any one of the preceding embodiments, wherein the oxide or mixed oxide support is MnO2 / ZrO2. 7. The catalyst composition according to any one of the preceding embodiments, wherein the oxide or mixed oxide support is WO3 / TiO2. 8. The catalyst composition according to any one of the preceding embodiments, wherein the oxide or mixed oxide support is WO3 / Al2O3. 9. The catalyst composition according to any one of the preceding embodiments, wherein the oxide or mixed oxide support is SiO2 / Al2O3. 10. The catalyst composition according to any one of the preceding embodiments, wherein the oxide or mixed oxide support is Ce / Zr / La. 11. The catalyst composition according to any one of the preceding embodiments, wherein the oxide or mixed oxide support is Ce / Zr / La / Y. 12. The catalyst composition according to any one of the preceding embodiments, wherein the oxide or mixed oxide support is CeO2. 13. The catalyst composition according to any one of the preceding embodiments, wherein the oxide or mixed oxide support is CeO2 / Al2O3. 14. The catalyst composition of any one of the preceding embodiments, wherein the metal oxide dopant is selected from MnO2, CeO2, Nb2O5, CuO, and combinations thereof. 15. The catalyst composition of any one of the preceding embodiments, wherein the metal oxide dopant is MnO2. 16. The catalyst composition of any one of the preceding embodiments, wherein the metal oxide dopant is CeO2. 17. The catalyst composition of any one of the preceding embodiments, wherein the metal oxide dopant is Nb2O5. 18. The catalyst composition of any one of the preceding embodiments, wherein the metal oxide dopant is CuO. 19. The catalyst composition according to any one of the preceding embodiments, wherein the H-zeolite is selected from structures including BEA, FER, MOR, MFI, FAU, CHA, and combinations thereof. 20. The catalyst composition according to any one of the preceding embodiments, wherein the H-zeolite structure comprises BEA. 21. The catalyst composition according to any one of the preceding embodiments, wherein the H-zeolite structure comprises FER. 22. The catalyst composition according to any one of the preceding embodiments, wherein the H-zeolite structure comprises MOR. 23. The catalyst composition according to any one of the preceding embodiments, wherein the H-zeolite structure comprises MFI. 24. The catalyst composition according to any one of the preceding embodiments, wherein the H-zeolite structure comprises FAU. 25. The catalyst composition according to any one of the preceding embodiments, wherein the H-zeolite structure comprises CHA. 26. The catalyst composition of any one of the preceding embodiments, wherein the H-zeolite constitutes about 5% to about 50% by weight of the oxide catalyst. 27. The catalyst composition of any one of the preceding embodiments, wherein the H-zeolite constitutes about 10% to about 40% by weight of the oxide catalyst. 28. The catalyst composition of any one of the preceding embodiments, wherein the H-zeolite constitutes about 20% to about 30% by weight of the oxide catalyst. 29. The catalyst composition of any one of the preceding embodiments, wherein the H-zeolite constitutes about 20% by weight of the oxide catalyst. 30. The catalyst composition of any one of the preceding embodiments, wherein the metal dopant comprises from about 1% to about 20% by weight of the oxide catalyst. 31. The catalyst composition of any one of the preceding embodiments, wherein the metal dopant comprises from about 2% to about 10% by weight of the oxide catalyst. 32. The catalyst composition of any one of the preceding embodiments, wherein the metal dopant constitutes about 5% by weight of the oxide catalyst. 33. The catalyst composition of any one of the preceding embodiments, wherein the oxide or mixed oxide support is about 20% CeO2 / Al2O3. 34. The catalyst composition of any one of the preceding embodiments, wherein the metal oxide dopant is about 5% by weight MnO2. 35. The catalyst composition of any one of the preceding embodiments, wherein the H-zeolite structure is about 20 wt. % BEA. 36. The catalyst composition of any one of the preceding embodiments, wherein the oxide or mixed oxide support is about 18% MnO2 / ZrO2. 37. The catalyst composition of any one of the preceding embodiments, wherein the H-zeolite structure is about 20 wt. % BEA. 38. The catalyst composition of any one of the preceding embodiments, wherein the composition is a powder. 39. The catalyst composition of any one of the preceding embodiments, wherein the composition is a coated monolith. 40. A process for producing a catalyst composition comprising: (a) impregnating one or more oxide dopants onto an oxide or mixed oxide support using an incipient wetness technique to form an oxide catalyst; (b) physically blending H-zeolite, or a zeolite that can be converted to H-zeolite, with an oxide catalyst in a slurry state; (c) calcining the blend at a temperature of at least about 450° C. for about 1 hour to obtain a catalyst composition; A process including. 41. A method for reducing NO in an exhaust gas comprising contacting the exhaust gas stream with a catalyst composition according to any one of embodiments 1 to 39 in the presence of a reducing agent. x A process that reduces formation. 42. The process of embodiment 41, wherein the process temperature is about 250° C. or less. 43. The process of embodiment 42, wherein the temperature of the process is about 200°C. 44. A catalytic article comprising a substrate having a plurality of channels for gas flow and a catalytic composition according to embodiment 1 or embodiment 2 disposed thereon. 45. NO x 45. A method of treating an exhaust gas comprising contacting the exhaust gas with the catalytic article of embodiment 44 at a temperature in the range of about 200° C. to about 250° C. or greater for a period of time. 46. ​​The method of embodiment 45, used in high-load applications located in close-coupled positions. 47. NO in exhaust gas at about 250°C x 47. The method of embodiment 46, wherein the conversion level is at least about 18% higher than the catalyst composition in which the H-zeolite or zeolite that can be converted to H-zeolite is not blended. 48. The method of embodiment 46, wherein the formation of N2O at about 250° C. is at least about 5 times lower than in a catalyst composition in which the H-zeolite or a zeolite that can be converted to H-zeolite is not blended. 49. An emission treatment system for treating an exhaust gas stream, comprising: an engine generating an exhaust gas stream; 45. The catalytic article of embodiment 44 disposed downstream of an engine in fluid communication with the exhaust gas stream; An exhaust treatment system comprising: 50. Diesel Oxidation Catalyst (DOC), Catalyzed Soot Filter (CSF), Soot Filter, Ammonia Oxidation (AMO x ) Catalyst, Lean NO x 50. The emission treatment system of embodiment 49, further comprising one or more of a trap (LNT) and a nitrogen-based reductant injector. 51. The emission treatment system of embodiment 49, further comprising a diesel oxidation catalyst (DOC). 52. The exhaust treatment system of embodiment 49, further comprising a catalyzed soot filter (CSF). 53. The exhaust treatment system of embodiment 49, further comprising a soot filter. 54. Ammonia oxidation (AMO x 50. An emission treatment system as described in embodiment 49, further comprising a catalyst. 55. Lean NO x 50. The exhaust treatment system of embodiment 49, further comprising a trap (LNT). 56. The emission treatment system of embodiment 49, further comprising a nitrogen-based reductant injector.

Claims

1. NO using ammonia or urea ｘ A catalytic composition for treating exhaust gases comprising: A catalyst composition comprising an oxide or mixed oxide support impregnated with a metal oxide dopant to form an oxide catalyst, and comprising an H-zeolite or a zeolite that can be converted to an H-zeolite.

2. 10. The catalyst composition of claim 1, wherein the H-zeolite or the zeolite that can be converted to H-zeolite is blended with the oxide catalyst.

3. The oxide or mixed oxide support is MnO ２ / ZrO ２ , W.O. ３ / TiO ２ , W.O. ３ / Al ２ O ３ , SiO ２ / Al ２ O ３ , Ce / Zr / La, Ce / Zr / La / Y, CeO ２ , CeO ２ / Al ２ O ３ 3. The catalyst composition of claim 1 or 2, wherein the catalyst composition is selected from the group consisting of:

4. The metal oxide dopant is MnO ２ , CeO ２ , Nb ２ O ５ 3. The catalyst composition of claim 1, wherein the metal is selected from the group consisting of SiO, CuO, and combinations thereof.

5. 3. The catalyst composition of claim 1 or 2, wherein the H-zeolite or the zeolite that can be converted to an H-zeolite is selected from structures including BEA, FER, MOR, MFI, FAU, CHA, and combinations thereof, and / or the H-zeolite or the zeolite that can be converted to an H-zeolite comprises from about 5 wt % to about 50 wt % of the oxide catalyst.

6. 3. The catalyst composition of claim 1, wherein the metal dopant comprises from about 1% to about 20% by weight of the oxide catalyst.

7. The oxide or mixed oxide support contains about 20% CeO ２ / Al ２ O ３ and the metal oxide dopant is about 5% by weight MnO ２ and the H-zeolite structure or the zeolite structure that can be converted to an H-zeolite structure is about 20 wt. % BEA, or the oxide or mixed oxide support is about 18% MnO ２ / ZrO ２ 3. The catalyst composition of claim 1 or 2, wherein the H-zeolite structure or the zeolite structure that can be converted to an H-zeolite structure is about 20 wt. % BEA.

8. 3. The catalyst composition of claim 1 or 2, wherein the composition is a powder or a coated monolith.

9. 1. A process for producing a catalyst composition, comprising: (a) impregnating one or more oxide dopants onto an oxide or mixed oxide support using an incipient wetness technique to form an oxide catalyst; (b) physically blending H-zeolite, or a zeolite that can be converted to H-zeolite, with the oxide catalyst in a slurry state to form a blend; (c) calcining the blend at a temperature of at least about 450°C for about 1 hour to obtain the catalyst composition; A process involving:

10. 3. A method for reducing NO in an exhaust gas stream comprising contacting the exhaust gas stream with the catalyst composition of claim 1 or 2 in the presence of a reducing agent. ｘ A process that reduces formation.

11. 11. The process of claim 10, wherein the process temperature is about 250°C or less, preferably about 200°C.

12. A catalytic article comprising a substrate having a plurality of channels for gas flow and the catalytic composition of claim 1 disposed thereon.

13. NO ｘ 13. A method for treating an exhaust gas comprising contacting the exhaust gas with the catalytic article of claim 12 at a temperature in the range of about 200°C to about 250°C or greater for a period of time, optionally for use in a high load application located in a close coupled position.

14. NO in the exhaust gas at about 250°C ｘ The conversion level is at least about 18% higher than the catalyst composition without the H-zeolite or zeolite that can be converted to H-zeolite, or ... ２ 14. The method of claim 13, wherein the formation of O is at least about 5 times lower than a catalyst composition that is not blended with H-zeolite or a zeolite that can be converted to H-zeolite.

15. 1. An emissions treatment system for treating an exhaust gas stream, comprising: an engine generating an exhaust gas stream; 13. The catalytic article of claim 12 disposed downstream of the engine in fluid communication with the exhaust gas flow; and optionally a diesel oxidation catalyst (DOC), a catalyzed soot filter (CSF), a soot filter, an ammonia oxidation (AMO) ｘ ) Catalyst, Lean NO ｘ a liquid nitrogen trap (LNT), and a nitrogen-based reductant injector; Emissions treatment system.

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