Ammonia Oxidation Catalysts for Diesel Applications

Abstract

The present invention relates to an ammonia oxidation catalyst for treating exhaust gas streams, the catalyst comprising a coating disposed on a substrate, the coating comprising: a selective catalytic reduction component which is a zeolitic material comprising one or more of copper and iron; and an oxidation catalyst component comprising platinum supported on a porous non-zeolitic oxide support, the oxidation catalyst component further comprising a first oxide material supported on the porous non-zeolitic oxide support supporting platinum, the first oxide material comprising titania.

Description

[Technical field]

[0001] The present invention relates to an ammonia oxidation catalyst for treating exhaust gas streams, a method for preparing the ammonia oxidation catalyst, and a method for oxidizing ammonia using the catalyst of the present invention. [Background technology]

[0002] Many exhaust gas purification systems for diesel engines use ammonia (NH 3 ) are or will be equipped with active catalysts for the selective reduction of NOx by ammonia (NH 3 ) is often produced from a urea solution injected into the exhaust gas of an exhaust gas treatment system. Under certain conditions, if more ammonia is injected than is consumed in the reduction of NOx, ammonia may be released from the exhaust system into the environment. However, ammonia is a toxic gas. Such release of ammonia must be prevented. Therefore, an ammonia oxidation (AMOX) catalyst can be arranged at the outlet of the exhaust gas system to oxidize ammonia, preferably to harmless nitrogen. WO2010 / 062730A2 discloses a layered or zoned AMOX catalyst comprising Cu-CHA and platinum on alumina. EP2878360A1 discloses an exhaust gas purification catalyst comprising a lower catalyst layer comprising a NOx reduction catalyst, a front upper layer comprising a NOx reduction catalyst arranged on the lower catalyst layer, and a rear upper layer comprising an oxidation catalyst arranged on the lower catalyst layer. Furthermore, ammonia oxidation catalysts are known to oxidize ammonia to NOx at temperatures exceeding 400° C. depending on the concentration and flow rate. However, this leads to excess NOx emissions that need to be avoided. Thus, there remains a need to provide an ammonia oxidation catalyst for internal combustion engines, preferably diesel engines, that has reduced NOx formation at high temperatures. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] WO2010 / 062730A2 [Patent Document 2] EP2878360A1 Summary of the Invention [Problem to be solved by the invention]

[0004] Therefore, the object of the present invention is to prevent NOx formation at high temperatures and nitrous oxide (N 2 The objective of the present invention is to provide an improved ammonia oxidation catalyst capable of reducing NOx formation at high temperatures and the formation of nitrous oxide (N O). 2 It has been found that the formation of .O) can be reduced. [Means for solving the problem]

[0005] Accordingly, the present invention is directed to an ammonia oxidation catalyst for treating an exhaust gas stream, the catalyst comprising a coating disposed on a substrate, the coating comprising: (i) a selective catalytic reduction component that is a zeolitic material containing one or more of copper and iron; and (ii) an oxidation catalyst component comprising platinum supported on a porous non-zeolitic oxidic support, further comprising a first oxide material supported on the porous non-zeolitic oxidic support supporting the platinum, the first oxide material comprising titania; Includes. [Brief description of the drawings]

[0006] [Figure 1] FIG. 1 shows the ammonia light-off temperature, NOx and N2O formed (units: g / l) obtained with the catalysts of Comparative Example 3, Example 1 and Example 2. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] In the present invention, it is preferred that the exhaust gas stream is an exhaust gas stream exiting a diesel engine.

[0008] It is preferred that the selective catalytic reduction component according to (i) is a zeolitic material with 8-ring pores. More preferably, the zeolitic material with 8-ring pores has a framework type selected from the group consisting of CHA, AEI, RTH, LEV, DDR, KFI, ERI, AFX, mixtures of two or more thereof and mixed types of two or more thereof, more preferably selected from the group consisting of CHA, AEI, RTH, mixtures of two or more thereof and mixed types of two or more thereof, more preferably selected from the group consisting of CHA, AEI, mixtures of these two and mixed types of these two, more preferably selected from the group consisting of CHA and AEI. It is more preferred that the zeolitic material with 8-ring pores has a framework type CHA. It is more preferred that the zeolitic material with 8-ring pores is zeolite SSZ-13.

[0009] It is preferred that the zeolitic material has a skeletal structure, and 95-100% by mass, more preferably 98-100% by mass, and even more preferably 99-100% by mass of the skeletal structure of the zeolitic material is composed of Si, Al, O, and optionally H, and the molar ratio of Si to Al in the skeletal structure is SiO 2 :Al 2 O 3 and is more preferably in the range of 2:1 to 50:1, more preferably in the range of 5:1 to 40:1, more preferably in the range of 8:1 to 30:1, more preferably in the range of 9:1 to 24:1, and more preferably in the range of 10:1 to 22:1.

[0010] The zeolitic material preferably contains copper, and the amount of copper in the zeolitic material, calculated as CuO, is in the range of 0.1 to 10 mass %, more preferably in the range of 2 to 8 mass %, more preferably in the range of 3 to 7 mass %, more preferably in the range of 4 to 6.5 mass %, based on the total mass of the zeolitic material. The amount of iron contained in the zeolitic material is Fe 2 O 3and is preferably in the range of 0 to 0.01 mass %, more preferably in the range of 0 to 0.0 ... based on the total mass of the zeolite material. It will therefore be understood that in the present invention, it is more preferable that the zeolite material is substantially free of iron, more preferably free of iron. Alternatively, it is preferable that the zeolite material contains iron, and the amount of iron contained in the zeolite material is Fe 2 O 3 and based on the total mass of the zeolite material, is more preferably in the range of 0.1 to 10 mass%, more preferably in the range of 0.5 to 7 mass%, more preferably in the range of 1 to 5.5 mass%, more preferably in the range of 2 to 5.5 mass%.

[0011] The coating comprises selective catalytic component (i) at a concentration of 1 to 5 g / in 3 in the range of 1.2 to 4 g / in 3 More preferably, in the range of 1.5 to 3.5 g / in 3 It is preferable that the amount of the supported metal is in the range of 1.

[0012] It is preferred that 60 to 95 mass %, more preferably 70 to 92 mass %, and even more preferably 75 to 90 mass % of the coating consists of the selective catalyst component (i).

[0013] Accordingly, the present invention is preferably directed to an ammonia oxidation catalyst for treating an exhaust gas stream, the catalyst comprising a coating disposed on a substrate, the coating comprising: (i) a selective catalytic reduction component which is an 8-ring pore zeolite material containing one or more of copper and iron, more preferably copper (the zeolite material has a framework structure in which the molar ratio of Si to Al is less than or equal to 100% by weight of molar SiO 2 :Al 2 O 3 and more preferably in the range of 2:1 to 50:1, more preferably in the range of 5:1 to 40:1, more preferably in the range of 8:1 to 30:1, more preferably in the range of 9:1 to 24:1, more preferably in the range of 10:1 to 22:1), and (ii) an oxidation catalyst component comprising platinum supported on a porous non-zeolitic oxide support, further comprising a first oxide material supported on the porous non-zeolitic oxide support supporting the platinum, the first oxide material comprising titania; Includes.

[0014] In the present invention, it is preferred that the coating further comprises an oxide binder, which preferably comprises one or more of zirconia, alumina, titania, silica, and mixed oxides comprising two or more of Zr, Al, Ti, and Si. More preferably, the oxide binder comprises one or more of zirconia and alumina, more preferably zirconia.

[0015] With regard to the oxide binder, it is preferred that the coating comprises the oxide binder in an amount in the range of 1 to 10% by weight, more preferably in the range of 2 to 8% by weight, more preferably in the range of 3 to 6% by weight, based on the weight of the zeolitic material.

[0016] It is preferred that 65 to 95 mass %, more preferably 70 to 92 mass %, and even more preferably 75 to 90 mass % of the oxidation catalyst component is made of a porous non-zeolitic oxide support.

[0017] Preferably, the porous non-zeolitic oxide support comprises one or more of alumina, silica, zirconia, zirconia-alumina, silica-alumina, and mixtures of two or more thereof, more preferably one or more of alumina, zirconia-alumina, silica-alumina, and mixtures of two or more thereof. More preferably, the porous non-zeolitic oxide support comprises alumina.

[0018] The porous non-zeolitic oxide support preferably comprises 95 to 100% by mass, more preferably 98 to 100% by mass, more preferably 99 to 100% by mass, and more preferably 99.5 to 100% by mass of alumina.

[0019] The coating is carried out on a porous non-zeolitic oxide support at a concentration of 0.15 to 1.0 g / in 3 More preferably, the range is 0.15 to 0.75 g / in 3 More preferably, the range is 0.20 to 0.50 g / in 3 It is preferable that the amount of the supported metal is in the range of 1.

[0020] It is preferred that the coating comprises a selective catalytic reduction component (i) in a loading amount l1, (l1) and a porous non-zeolitic oxide support in a loading amount l3, (l3), and the loading ratio of the selective catalytic reduction component (i) to the porous non-zeolitic oxide support, expressed as (l1):(l3), is in the range of 1:1 to 25:1, more preferably in the range of 2:1 to 20:1, more preferably in the range of 3:1 to 15:1, more preferably in the range of 4:1 to 12:1, and more preferably in the range of 5:1 to 10:1.

[0021] Accordingly, the present invention is preferably directed to an ammonia oxidation catalyst for treating an exhaust gas stream, the catalyst comprising a coating disposed on a substrate, the coating comprising: (i) a selective catalytic reduction component which is an eight-ring pore zeolitic material containing one or more of copper and iron, more preferably copper; and (ii) an oxidation catalyst component comprising platinum supported on a porous non-zeolitic oxide support and further comprising a first oxide material supported on the porous non-zeolitic oxide support supporting platinum, the first oxide material comprising titania and the porous non-zeolitic oxide support comprising alumina; Including, The coating comprises a selective catalytic reduction component (i) in a loading amount l1, (l1) and a porous non-zeolitic oxide support in a loading amount l3, (l3), and the loading ratio of the selective catalytic reduction component (i) to the porous non-zeolitic oxide support, expressed as (l1):(l3), is in the range of 1:1 to 25:1, more preferably in the range of 2:1 to 20:1, more preferably in the range of 3:1 to 15:1, more preferably in the range of 4:1 to 12:1, and more preferably in the range of 5:1 to 10:1.

[0022] In the present invention, it is preferred that the platinum supported on the porous non-zeolitic oxide support has an average crystallite size less than 5 nm, preferably in the range of 0.001 to 3 nm, the average crystallite size being determined as described in Reference Example 10.

[0023] The platinum supported on the porous non-zeolitic oxide support of the catalyst preferably has an average crystallite size in the range of 5 to 100 nm, preferably in the range of 10 to 30 nm, more preferably in the range of 12 to 28 nm, more preferably in the range of 14 to 25 nm, when the catalyst is aged in a gas atmosphere at a temperature in the range of 700 to 800°C for a duration in the range of 10 to 20 hours (the gas atmosphere preferably contains 5 to 15% steam), the average crystallite size being determined as described in Reference Example 10. The aging is preferably carried out at a temperature in the range of 720 to 780°C, more preferably in the range of 740 to 760°C, more preferably in the range of 750°C, for a duration in the range of 14 to 18 hours, more preferably in the range of 15 to 17 hours, more preferably for a duration of 16 hours, the gas atmosphere preferably containing 8 to 12% steam, more preferably 10% steam.

[0024] Preferably the coating comprises platinum in an amount in the range 0.2 to 1.5 mass %, more preferably in the range 0.5 to 1.0 mass %, calculated as elemental platinum and based on the mass of the porous non-zeolitic oxide support.

[0025] The coating is performed with a platinum loading of 0.5 to 25 g / ft2, calculated as elemental platinum. 3 More preferably, the range is 0.75 to 15 g / ft 3 More preferably, the range is 1 to 8 g / ft 3 More preferably, it is in the range of 1.5 to 5 g / ft 3 It is preferable that the range is 100%.

[0026] It is preferred that the oxidation catalyst component further comprises one or more platinum group metals other than platinum, preferably one or more of palladium and rhodium, more preferably rhodium, and thus it is preferred that the oxidation component comprises platinum and rhodium.

[0027] Preferably, the coating comprises one or more platinum group metals other than platinum in an amount, calculated as elemental platinum group metal, based on the weight of the porous non-zeolitic oxide support, in the range 0.1 to 1.5%, more preferably in the range 0.2 to 0.9%, more preferably in the range 0.3 to 0.7% by weight.

[0028] The coating shall contain one or more platinum group metals other than platinum, calculated as elemental platinum group metals, in an amount of 0.5 to 20 g / ft 3 range, preferably 0.75 to 12 g / ft 3 More preferably, it is in the range of 1 to 6 g / ft 3 More preferably, it is in the range of 1.5 to 4 g / ft 3 It is preferable that the amount of the supported metal in the catalyst is in the range of 1 to 500 nm.

[0029] Accordingly, the present invention is preferably directed to an ammonia oxidation catalyst for treating an exhaust gas stream, the catalyst comprising a coating disposed on a substrate, the coating comprising: (i) a selective catalytic reduction component which is an eight-ring pore zeolitic material containing one or more of copper and iron, more preferably copper; and (ii) an oxidation catalyst component comprising platinum supported on a porous non-zeolitic oxide support and further comprising a first oxide material supported on the porous non-zeolitic oxide support supporting platinum, the first oxide material comprising titania and the porous non-zeolitic oxide support comprising alumina; Including, the coating comprises a selective catalytic reduction component (i) in a loading amount l1, (l1) and a porous non-zeolitic oxide support in a loading amount l3, (l3), the loading ratio of the selective catalytic reduction component (i) to the porous non-zeolitic oxide support, expressed as (l1):(l3), is in the range of 1:1 to 25:1, more preferably in the range of 2:1 to 20:1, more preferably in the range of 3:1 to 15:1, more preferably in the range of 4:1 to 12:1, more preferably in the range of 5:1 to 10:1; the coating comprises platinum in an amount in the range of 0.2 to 1.5 mass %, more preferably in the range of 0.5 to 1.0 mass %, calculated as elemental platinum, based on the mass of the porous non-zeolitic oxide support; the oxidation catalyst component further comprises one or more platinum group metals other than platinum, preferably one or more of palladium and rhodium, more preferably rhodium; More preferably, the coating comprises one or more platinum group metals other than platinum in an amount, calculated as elemental platinum group metal, based on the weight of the porous non-zeolitic oxide support, in the range of 0.1 to 1.5%, more preferably in the range of 0.2 to 0.9%, more preferably in the range of 0.3 to 0.7% by weight.

[0030] In the present invention, the coating is such that the total platinum group metal loading in the catalyst is 1 to 45 g / ft, calculated as elemental platinum group metal. 3 More preferably, the range is 1.5 to 27 g / ft 3 More preferably, the range is 2 to 14 g / ft 3 More preferably, the range is 3 to 9 g / ft 3 More preferably, the coating has a platinum + rhodium loading in the catalyst calculated as element Pt and element Rh in the range of 1 to 45 g / ft 3 More preferably, the range is 1.5 to 27 g / ft 3 More preferably, the range is 2 to 14 g / ft 3 More preferably, the range is 3 to 9 g / ft 3 It has a range of.

[0031] The coating preferably has a platinum loading l(a), calculated as elemental platinum, and a loading l(b), of one or more platinum group metals other than platinum, calculated as elemental platinum group metals, with the loading ratio of platinum to the one or more platinum group metals other than platinum, expressed as l(a):l(b), being in the range of 1:10 to 10:1, more preferably in the range of 1:5 to 8:1, more preferably in the range of 1:2 to 7:1, more preferably in the range of 1:1 to 6:1, more preferably in the range of 1.1:1 to 5:1, more preferably in the range of 1.2:1 to 3:1.

[0032] The first oxide material preferably comprises titania at 95 to 100 mass %, more preferably 98 to 100 mass %, more preferably 99 to 100 mass %, and even more preferably 99.5 to 100 mass %.

[0033] It is preferred that the coating comprises the first oxide material in an amount in the range of 1 to 20% by weight, more preferably in the range of 2 to 10% by weight, more preferably in the range of 2.5 to 7.5% by weight, more preferably in the range of 3 to 6% by weight, based on the weight of the porous non-zeolitic oxide support.

[0034] It is preferred that 0-0.1% by weight of the coating is made up of cerium, preferably 0-0.01% by weight, more preferably 0-0.001% by weight, more preferably 0.0001% by weight. It will therefore be appreciated that in the present invention, it is preferred that the coating is substantially free of cerium, more preferably free of cerium. More preferably, the catalyst is substantially free of cerium, more preferably free of cerium.

[0035] According to the first aspect of the present invention, it is preferred that 95-100% by mass of the coating consists of an oxidation catalyst component (ii) comprising platinum, a porous non-zeolitic oxide support and a first oxide material comprising titania, the oxidation catalyst component more preferably further comprising one or more platinum group metals other than platinum, a selective catalytic reduction component (i) and more preferably an oxide binder as defined above.

[0036] In the present invention, preferably, the oxidation catalyst component further comprises a second oxide material supported on a porous non-zeolitic oxide support, the second oxide material comprising one or more of manganese, cerium, tungsten, molybdenum, praseodymium, europium, chromium, cobalt, technetium, rhenium, ruthenium, vanadium and indium, more preferably one or more of manganese, cerium, tungsten, praseodymium and indium, more preferably one or more of manganese, cerium and praseodymium, more preferably one or more of manganese and cerium. More preferably, the second oxide material is manganese, more preferably manganese oxide, more preferably MnO, Mn 2 O 3 , Mn 3 O 4 and MnO 2 Contains one or more of the following:

[0037] The second oxide material preferably comprises 95 to 100 mass %, more preferably 98 to 100 mass %, more preferably 99 to 100 mass %, and more preferably 99.5 to 100 mass % of manganese and oxygen.

[0038] It is preferred that the coating comprises the second oxide material in an amount in the range 1 to 20% by weight, more preferably in the range 2 to 10% by weight, based on the weight of the porous non-zeolitic oxide support.

[0039] According to a second aspect of the present invention, it is preferred that 95-100% by mass of the coating consists of a platinum-containing oxidation catalyst component (ii), a porous non-zeolitic oxide support, a first oxide material comprising titania, and a second oxide material, the oxidation catalyst component more preferably further comprising one or more platinum group metals other than platinum, a selective catalytic reduction component (i), and more preferably an oxide binder as defined above.

[0040] In the present invention, it is preferred that the substrate is a flow-through substrate or a wall-flow filter substrate, more preferably a flow-through substrate.

[0041] It is preferred that the substrate comprises, more preferably consists of, one or more of cordierite, aluminum titanate, mullite and silicon carbide, more preferably cordierite, aluminum titanate and silicon carbide, more preferably cordierite. It is more preferred that the substrate is a cordierite flow-through substrate. Alternatively, it is preferred that the substrate comprises, more preferably consists of a metallic material, which more preferably comprises, more preferably consists of oxygen and one or more of iron, chromium and aluminum. It is more preferred that the substrate is a metallic flow-through substrate.

[0042] In the present invention, it is preferred that the substrate has an inlet end, an outlet end, a substrate axial length extending from the inlet end to the outlet end, and a plurality of passages defined by an inner wall of the substrate extending through the substrate, the interface between the passages and the inner wall being defined by a surface of the inner wall. More preferably, a coating is disposed on the surface of the inner wall of the substrate and extends over 95-100%, more preferably over 98-100%, more preferably over 99-100% of the substrate axial length. More preferably, the coating extends from the inlet end to the outlet end of the substrate.

[0043] The catalyst is 1 to 6 g / in 3 More preferably, in the range of 1.5 to 4.5 g / in 3 More preferably, in the range of 1.75 to 3.75 g / in 3 It is preferred to include the coating at a loading in the range of 100 to 2000 nm.

[0044] The catalyst preferably consists of a substrate and a coating.

[0045] The present invention further relates to an aged catalyst, which is a catalyst according to the invention, hereinafter (i) heating the catalyst in a gas atmosphere at a temperature in the range of 700-800° C. for a duration in the range of 10-20 hours, the gas atmosphere preferably containing 5-15% steam; and is obtainable or obtained by a method comprising, preferably consisting of, subjecting the material to an ageing treatment comprising, preferably consisting of: The aged catalyst comprises platinum supported on a porous non-zeolitic oxide support exhibiting an average crystallite size in the range of 5-100 nm, preferably in the range of 10-30 nm, more preferably in the range of 12-28 nm, more preferably in the range of 14-25 nm, the average crystallite size being determined as described in Reference Example 10. More preferably, the aging treatment consists of heating the catalyst according to the invention at a temperature of 750° C. for 16 hours with 10% steam.

[0046] The present invention further relates to a method for preparing an ammonia oxidation catalyst according to the present invention, which method comprises the following steps: (a) preparing a first mixture comprising water, a selective catalytic reduction component which is a zeolitic material containing one or more of copper and iron, and preferably a precursor of an oxide binder, more preferably an oxide binder as defined above; (b) preparing a second mixture comprising water, a source of oxidation catalyst components comprising a source of platinum, a porous non-zeolitic oxide support, and a first oxide material comprising titania; (c) mixing the first mixture obtained in step (a) with the second mixture obtained in step (b); (d) disposing the mixture obtained in step (c) on a substrate, and optionally drying the substrate on which the mixture is disposed; (e) calcining the substrate obtained in step (d). Includes.

[0047] With regard to step (a), it is preferred that this further comprises the steps of: (a.1) preparing a mixture comprising water and a precursor of an oxide binder, the precursor being more preferably one or more of an aluminum salt, a silicon salt, a zirconium salt, and a titanium salt, more preferably one or more of a zirconium salt and an aluminum salt, more preferably a zirconium salt, more preferably zirconium acetate; (a.2) adding a selective catalytic reduction component which is a zeolitic material containing one or more of copper and iron, more preferably an 8 ring pore zeolitic material containing copper, to the mixture resulting from step (a.1).

[0048] With regard to step (b), it is preferred that this further comprises the steps of: (b.1) impregnating a source of platinum on a porous non-zeolitic oxide support with an adjuvant, the adjuvant preferably being one or more of water and an alcohol, more preferably water; (b.2) impregnating the impregnated porous non-zeolitic oxide support obtained in step (b.1) with a source of one or more platinum group metals, preferably other than platinum; (b.3) impregnating the impregnated porous non-zeolitic oxide support obtained in step (b.1), preferably obtained in step (b.2), with a solution containing a source of a first oxide material comprising titania, preferably a titania hydrogel, to obtain a mixture; (b.4) optionally adding a source of a second oxide material to the mixture obtained in step (b.3); (b.5) drying and / or calcining the mixture obtained in step (b.3), and optionally the mixture obtained in step (b.4), to obtain a powder; (b.6) preparing a mixture comprising water and the powder obtained in step (b.5); (b.7) preferably milling the particles of the mixture obtained in step (b.6), more preferably until the particles of the mixture have a Dv90 in the range of 3 to 30 micrometers, more preferably in the range of 5 to 20 micrometers, more preferably in the range of 8 to 18 micrometers (Dv90 is determined as described in Reference Example 1).

[0049] More preferably, step (b) comprises steps (b.1), (b.2), (b.3), (b.5), (b.6) and more preferably (b.7). Alternatively, more preferably, step (b) comprises steps (b.1), (b.2), (b.3), (b.4), (b.5), (b.6) and more preferably (b.7).

[0050] Preferably, the impregnation according to step (b.3) is carried out by adding, under stirring, a solution containing the source of the first oxide material to the impregnated porous non-zeolitic oxide support obtained in step (b.1), more preferably in step (b.2).

[0051] Preferably, step (b.4) is carried out by adding a source of the second oxide material to the mixture obtained in step (b.3) with stirring.

[0052] It is preferred that the source of second oxide material provided in step (b.4) is a source comprising one or more of manganese, cerium, tungsten, molybdenum, praseodymium, europium, chromium, cobalt, technetium, rhenium, ruthenium, vanadium and indium, more preferably comprising one or more of manganese, cerium, tungsten, praseodymium and indium, more preferably comprising one or more of manganese, cerium and praseodymium, more preferably comprising one or more of manganese and cerium, more preferably comprising a source comprising manganese.

[0053] Preferably, the source of the second oxide material provided in step (b.4) is a salt, more preferably a nitrate, more preferably manganese nitrate.

[0054] With regard to step (b), it is preferred that this alternatively further comprises the steps of: (b.1') impregnating a source of platinum onto a porous non-zeolitic oxide support with an adjuvant, the adjuvant being more preferably one or more of water and an alcohol, more preferably water; (b.2') impregnating the impregnated porous non-zeolitic oxide support obtained in step (b.1) with a solution containing a source of a first oxide material comprising titania, more preferably a titania hydrogel, to obtain a mixture; (b.3') impregnating a source of one or more platinum group metals other than platinum onto the impregnated porous non-zeolitic oxide support obtained in step (b.2'); (b.4') drying and / or calcining the mixture obtained in step (b.3') to obtain a powder, (b.5') preparing a mixture comprising water and the powder obtained in step (b.4'); (b.6') preferably milling the particles of the mixture obtained in step (b.5'), more preferably until the particles of the mixture have a Dv90 in the range of 3 to 30 micrometers, more preferably in the range of 5 to 20 micrometers, more preferably in the range of 8 to 18 micrometers (Dv90 is determined as described in Reference Example 1).

[0055] More preferably, step (b) comprises steps (b.1'), (b.2'), (b.3'), (b.4'), (b.5') and more preferably (b.6').

[0056] Preferably, the impregnation according to step (b.2') is carried out by adding, with stirring, a solution containing the source of the first oxide material to the impregnated porous non-zeolitic oxide support obtained in step (b.1').

[0057] Preferably, the source of one or more platinum group metals other than platinum provided in step (b.2), or step (b.3'), is one or more of a source of rhodium and a source of palladium, more preferably one or more of a rhodium nitrate solution and a palladium nitrate solution, more preferably a rhodium nitrate solution.

[0058] Preferably, the drying according to step (b.5) or step (b.4') is carried out in a gas atmosphere having a temperature in the range of 90 to 160° C., more preferably in the range of 110 to 130° C., the gas atmosphere more preferably comprising oxygen.

[0059] Preferably, the calcination according to step (b.5) or (b.4') is carried out in a gas atmosphere having a temperature in the range of from 300 to 800° C., more preferably in the range of from 400 to 700° C., the gas atmosphere more preferably comprising oxygen.

[0060] It is preferred that the porous non-zeolitic oxide support provided in step (b) comprises pores having an average pore size in the range of 8-45 nm, more preferably in the range of 10-40 nm, more preferably in the range of 12-30 nm, more preferably in the range of 15-25 nm, the average pore size being determined as described in Reference Example 2.

[0061] The porous non-zeolitic oxide support provided in step (b) has a melting point of 0.6 ml / cm 3 ~2ml / cm 3 more preferably in the range of 0.65 ml / cm 3 ~1.75ml / cm 3 More preferably in the range of 0.70 ml / cm 3 ~1.5ml / cm 3 More preferably, the average pore volume is in the range of

[0062] The porous non-zeolitic oxide support provided in step (b) is 40 to 300 m 2 / g, more preferably 50 to 200m 2 / g, more preferably 70 to 160 m 2 / g, the BET specific surface area being determined as described in Reference Example 3.

[0063] The porous non-zeolitic oxide support preferably comprises 95 to 100% by mass, more preferably 98 to 100% by mass, more preferably 99 to 100% by mass, and more preferably 99.5 to 100% by mass of alumina.

[0064] The placing of the mixture obtained in step (c) according to step (d) is preferably carried out by spraying the mixture onto the substrate or by immersing the substrate in the mixture, preferably by immersing the substrate in the mixture.

[0065] The substrate provided in step (d) preferably has an inlet end, an outlet end, a substrate axial length extending from the inlet end to the outlet end, and a plurality of passages defined by an inner wall of the substrate extending through the substrate, the interface between the passages and the inner wall defining a surface of the inner wall.

[0066] It is preferred that the mixture obtained in step (c) is arranged from the inlet end to the outlet end over 95 to 100%, more preferably 98 to 100%, and more preferably 99 to 100% of the axial length of the substrate by step (d).

[0067] Preferably, the substrate provided in step (d) is a flow-through substrate or a wall-flow filter substrate, more preferably a flow-through substrate. Preferably, the substrate provided in step (d) is a ceramic substrate, more preferably the substrate comprises, more preferably consists of, one or more of cordierite, aluminum titanate, mullite and silicon carbide, more preferably one or more of cordierite, aluminum titanate and silicon carbide, more preferably cordierite. Preferably, the substrate is a cordierite flow-through substrate. Alternatively, preferably, the substrate provided in step (d) comprises, more preferably consists of, a metallic material, more preferably the metallic material comprises, more preferably consists of, oxygen and one or more of iron, chromium and aluminum. More preferably, the substrate is a metallic flow-through substrate.

[0068] Preferably, the drying according to step (d) is carried out in a gas atmosphere having a temperature in the range of 90 to 180° C., more preferably in the range of 110 to 130° C., the gas atmosphere more preferably containing oxygen.

[0069] The drying in step (d) is preferably carried out in a gas atmosphere for a duration in the range of 10 to 300 minutes, more preferably in the range of 60 to 120 minutes, the gas atmosphere more preferably containing oxygen.

[0070] The calcination according to step (e) is preferably carried out in a gas atmosphere having a temperature in the range of 300 to 800° C., more preferably in the range of 450 to 650° C., the gas atmosphere more preferably containing oxygen.

[0071] The calcination according to step (e) is preferably carried out in a gas atmosphere for a duration ranging from 10 to 300 minutes, more preferably ranging from 60 to 120 minutes, the gas atmosphere more preferably containing oxygen.

[0072] The method preferably further comprises the steps of: (f) a step of ageing the product obtained in step (e) in a gas atmosphere, more preferably in a gas atmosphere having a temperature in the range of 600-900°C, more preferably in the range of 700-800°C, the gas atmosphere more preferably containing oxygen.

[0073] The aging in step (f) is preferably carried out for a duration in the range of 3 to 40 hours, more preferably in the range of 5 to 25 hours, and more preferably in the range of 10 to 20 hours.

[0074] In the ammonia oxidation catalyst obtained in step (f), the platinum supported on the porous non-zeolitic oxide support preferably has an average crystallite size in the range of 5 to 100 nm, preferably in the range of 10 to 30 nm, more preferably in the range of 12 to 28 nm, more preferably in the range of 14 to 25 nm, the average crystallite size being determined as described in Reference Example 10.

[0075] Preferably the method comprises steps (a), (b), (c), (d), (e) and optionally (f).

[0076] The present invention further relates to an ammonia oxidation catalyst obtained or obtainable by the process according to the invention.

[0077] The present invention further relates to the use of an ammonia oxidation catalyst according to the invention for the oxidation of ammonia, the ammonia being preferably contained in an exhaust gas stream from a diesel engine.

[0078] The present invention further relates to a method for oxidizing ammonia, the ammonia being contained in an exhaust gas stream, the method comprising: (1) providing an exhaust gas stream, preferably from a diesel engine; (2) passing the exhaust gas stream provided in step (1) through a catalyst according to the present invention.

[0079] The present invention is further described by the following set of embodiments and combinations of embodiments resulting from the indicated dependencies and back references. In particular, in each instance where a range of embodiments is mentioned, for example in the context of a term such as "the ammonia oxidation catalyst according to any one of embodiments 1 to 3", it is to be noted that it means that all embodiments within this range are expressly disclosed to those skilled in the art, i.e., the wording of this term is understood by those skilled in the art to be equivalent to "the ammonia oxidation catalyst according to any one of embodiments 1, 2 and 3". Furthermore, it is expressly pointed out that the following set of embodiments is not a set of claims that determines the scope of protection, but represents a suitably constructed part of the description directed to the general and preferred aspects of the present invention.

[0080] 1. (i) a selective catalytic reduction component that is a zeolitic material containing one or more of copper and iron; and (ii) an oxidation catalyst component comprising platinum supported on a porous non-zeolitic oxide support, further comprising a first oxide material supported on the porous non-zeolitic oxide support supporting the platinum, the first oxide material comprising titania; 1. An ammonia oxidation catalyst for treating an exhaust gas stream comprising: disposed on a substrate a coating comprising:

[0081] 2. The selective catalytic reduction component according to (i) is an 8-ring pore zeolitic material, the 8-ring pore zeolitic material having a framework type selected from the group consisting of CHA, AEI, RTH, LEV, DDR, KFI, ERI, AFX, mixtures of two or more thereof and mixed types of two or more thereof, more preferably selected from the group consisting of CHA, AEI, RTH, mixtures of two or more thereof and mixed types of two or more thereof, more preferably selected from the group consisting of CHA, AEI, mixtures of two or more thereof and mixed types of two or more thereof, more preferably selected from the group consisting of CHA and AEI, more preferably CHA; 2. The catalyst of embodiment 1, wherein the 8-ring pore zeolitic material is more preferably zeolite SSZ-13.

[0082] 3. The zeolite material has a skeletal structure, and 95 to 100 mass %, preferably 98 to 100 mass %, more preferably 99 to 100 mass % of the skeletal structure of the zeolite material is composed of Si, Al, O, and optionally H, and the molar ratio of Si to Al in the skeletal structure is SiO 2 :Al 2 O 3 and is preferably in the range of 2:1 to 50:1, more preferably in the range of 5:1 to 40:1, more preferably in the range of 8:1 to 30:1, more preferably in the range of 9:1 to 24:1, more preferably in the range of 10:1 to 22:1.

[0083] 4. The catalyst according to any one of the preceding claims, wherein the zeolitic material comprises copper and the amount of copper in the zeolitic material, calculated as CuO, is in the range of 0.1 to 10% by weight, preferably in the range of 2 to 8% by weight, more preferably in the range of 3 to 7% by weight, more preferably in the range of 4 to 6.5% by weight, based on the total weight of the zeolitic material.

[0084] 5. The amount of iron contained in the zeolite material is Fe 2 O 35, calculated as 0 to 0.01% by weight, preferably 0 to 0.001% by weight, more preferably 0 to 0.0001% by weight, based on the total weight of the zeolitic material.

[0085] 6. The zeolite material contains iron, and the amount of iron contained in the zeolite material is Fe 2 O 3 5. The catalyst according to any one of the preceding claims, wherein the zeolitic material content is preferably in the range of 0.1 to 10% by weight, more preferably in the range of 0.5 to 7% by weight, more preferably in the range of 1 to 5.5% by weight, more preferably in the range of 2 to 5.5% by weight, based on the total weight of the zeolitic material.

[0086] 7. The coating comprises selective catalytic component (i) at a concentration of 1 to 5 g / in 3 in the range of 1.2 to 4 g / in 3 More preferably, in the range of 1.5 to 3.5 g / in 3 In the range of loading amount, 7. The catalyst according to any one of the preceding claims, wherein preferably 60-95% by weight, more preferably 70-92% by weight, more preferably 75-90% by weight of the coating consists of the optional catalytic component (i).

[0087] 8. The coating further comprises an oxide binder, the oxide binder preferably comprising: Zirconia, alumina, titania, silica, and Mixed oxides containing two or more of Zr, Al, Ti, and Si and the oxide binder more preferably comprises one or more of zirconia and alumina, more preferably zirconia.

[0088] 9. The catalyst according to embodiment 8, wherein the coating comprises an oxide binder in an amount in the range of 1 to 10% by weight, preferably in the range of 2 to 8% by weight, more preferably in the range of 3 to 6% by weight, based on the weight of the zeolitic material.

[0089] 10. The catalyst according to any one of the preceding embodiments, wherein 65 to 95% by weight, preferably 70 to 92% by weight, more preferably 75 to 90% by weight of the oxidation catalyst component consists of the porous non-zeolitic oxide support.

[0090] 11. The porous non-zeolitic oxide support comprises one or more of alumina, silica, zirconia, zirconia-alumina, silica-alumina, and mixtures of two or more thereof, more preferably one or more of alumina, zirconia-alumina, silica-alumina, and mixtures of two or more thereof, the porous non-zeolitic oxide support more preferably comprises alumina; The catalyst according to any one of the preceding embodiments, wherein the porous non-zeolitic oxide support comprises, more preferably, 95 to 100% by mass, more preferably, 98 to 100% by mass, more preferably, 99 to 100% by mass, more preferably, 99.5 to 100% by mass of alumina.

[0091] 12. The coating is carried out on a porous non-zeolitic oxide support at a concentration of 0.15 to 1.0 g / in 3 in the range of 0.15 to 0.75 g / in 3 More preferably, the range is 0.20 to 0.50 g / in 3 12. The catalyst of any one of the preceding embodiments, comprising a loading in the range of

[0092] 13. The catalyst according to any one of embodiments 1 to 12, wherein the coating comprises a loading l1, (l1) of the selective catalytic reduction component (i) and a loading l3, (l3) of the porous non-zeolitic oxide support, and the loading ratio of the selective catalytic reduction component (i) to the porous non-zeolitic oxide support, expressed as (l1):(l3), is in the range of 1:1 to 25:1, preferably in the range of 2:1 to 20:1, more preferably in the range of 3:1 to 15:1, more preferably in the range of 4:1 to 12:1, more preferably in the range of 5:1 to 10:1.

[0093] 14. The catalyst according to any one of embodiments 1 to 13, wherein the platinum supported on the porous non-zeolitic oxide support has an average crystallite size in the range of 5 to 100 nm, preferably in the range of 10 to 30 nm, more preferably in the range of 12 to 28 nm, more preferably in the range of 14 to 25 nm, when the catalyst is aged in a gas atmosphere at a temperature in the range of 700 to 800° C. for a duration in the range of 10 to 20 hours (the gas atmosphere preferably containing 5 to 15% steam), the average crystallite size being determined as described in Reference Example 10.

[0094] 15. The coating comprises platinum in an amount in the range of 0.2 to 1.5 mass %, preferably in the range of 0.5 to 1.0 mass %, calculated as elemental platinum, based on the mass of the porous non-zeolitic oxide support; The coating has a platinum loading of 0.5 to 25 g / ft2, calculated as elemental platinum. 3 in the range of 0.75 to 15 g / ft 3 More preferably, the range is 1 to 8 g / ft 3 More preferably, it is in the range of 1.5 to 5 g / ft 3 15. The catalyst of any one of the preceding embodiments, wherein

[0095] 16. The oxidation catalyst component further comprises one or more platinum group metals other than platinum, preferably one or more of palladium and rhodium, more preferably rhodium; The coating preferably contains one or more platinum group metals other than platinum in an amount of from 0.5 to 20 g / ft, calculated as elemental platinum group metal. 3 range, preferably 0.75 to 12 g / ft 3 More preferably, it is in the range of 1 to 6 g / ft 3 More preferably, it is in the range of 1.5 to 4 g / ft 3 16. The catalyst of any one of the preceding embodiments, wherein the catalyst comprises a loading in the catalyst in the range of

[0096] 17. The coating provides a total platinum group metal loading in the catalyst of 1 to 45 g / ft, calculated as elemental platinum group metal. 3 range, preferably 1.5 to 27 g / ft3 More preferably, the range is 2 to 14 g / ft 3 More preferably, the range is 3 to 9 g / ft 3 17. The catalyst of embodiment 15 or 16, wherein

[0097] 18. The catalyst according to any one of embodiments 15 to 17, wherein the coating has a loading of platinum, l(a), calculated as elemental platinum, and a loading of one or more platinum group metals other than platinum, l(b), calculated as elemental platinum group metals, and the loading ratio of platinum to the one or more platinum group metals other than platinum, expressed as l(a):l(b), is in the range of 1:10 to 10:1, preferably in the range of 1:5 to 8:1, more preferably in the range of 1:2 to 7:1, more preferably in the range of 1:1 to 6:1, more preferably in the range of 1.1 to 5:1, more preferably in the range of 1.2:1 to 3:1.

[0098] 19. The catalyst according to any one of the preceding embodiments, wherein 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 first oxide material consists of titania.

[0099] 20. The catalyst according to any one of the preceding embodiments, wherein the coating comprises the first oxide material in an amount in the range of 1 to 20% by weight, preferably in the range of 2 to 10% by weight, more preferably in the range of 2.5 to 7.5% by weight, more preferably in the range of 3 to 6% by weight, based on the weight of the porous non-zeolitic oxide support.

[0100] 21. The catalyst according to any one of embodiments 1 to 20, wherein 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 consists of an oxidation catalyst component (ii) comprising platinum, a porous non-zeolitic oxide support, and a first oxide material comprising titania, the oxidation catalyst component preferably further comprising one or more platinum group metals other than platinum, a selective catalytic reduction component (i), and preferably an oxide binder as defined in embodiment 8 or 9.

[0101] 22. The oxidation catalyst component further comprises a second oxide material supported on a porous non-zeolitic oxide support, the second oxide material comprising one or more of manganese, cerium, tungsten, molybdenum, praseodymium, europium, chromium, cobalt, technetium, rhenium, ruthenium, vanadium and indium, preferably one or more of manganese, cerium, tungsten, praseodymium and indium, more preferably one or more of manganese, cerium and praseodymium, more preferably one or more of manganese and cerium, and the second oxide material is more preferably manganese, more preferably manganese oxide, more preferably MnO, Mn 2 O 3 , Mn 3 O 4 and MnO 2 21. The catalyst of any one of the preceding embodiments, comprising one or more of:

[0102] 23. The catalyst according to embodiment 22, wherein 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 oxide material consists of manganese and oxygen.

[0103] 24. The catalyst of embodiment 22 or 23, wherein the coating comprises the second oxide material in an amount in the range of 1 to 20% by weight, preferably in the range of 2 to 10% by weight, based on the weight of the porous non-zeolitic oxide support.

[0104] 25. The catalyst according to any one of embodiments 22 to 24, wherein 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 consists of an oxidation catalyst component (ii) comprising platinum, a porous non-zeolitic oxide support, a first oxide material comprising titania, and a second oxide material, the oxidation catalyst component preferably further comprising one or more platinum group metals other than platinum, a selective catalytic reduction component (i), and preferably an oxide binder as defined in embodiment 8 or 9.

[0105] 26. The substrate is a flow-through substrate or a wall-flow filter substrate, preferably a flow-through substrate; 26. The catalyst of any one of the preceding embodiments, wherein the substrate preferably comprises, more preferably consists of, one or more of cordierite, aluminum titanate, mullite, and silicon carbide, more preferably cordierite, aluminum titanate, and silicon carbide, more preferably cordierite; the substrate is more preferably a cordierite flow-through substrate; or the substrate preferably comprises, more preferably consists of a metal material, which preferably comprises, more preferably consists of oxygen and one or more of iron, chromium, and aluminum; and the substrate is more preferably a metal flow-through substrate.

[0106] 27. The catalyst of any one of embodiments 1 to 26, wherein the substrate has an inlet end, an outlet end, an axial length of the substrate extending from the inlet end to the outlet end, and a plurality of passages defined by an inner wall of the substrate extending through the substrate, the interface between the passages and the inner wall being defined by a surface of the inner wall.

[0107] 28. The catalyst of embodiment 27, wherein the coating is disposed on a surface of the inner wall of the substrate and extends over 95-100%, preferably 98-100%, and more preferably 99-100% of the axial length of the substrate, the coating preferably extending from the inlet end to the outlet end of the substrate.

[0108] 29. Coating: 1-6g / in 3 in the range of 1.5 to 4.5 g / in 3 More preferably, in the range of 1.75 to 3.75 g / in 3 29. The catalyst of any one of the preceding embodiments, comprising a loading in the range of

[0109] 30. The catalyst of any one of the preceding embodiments, comprising a substrate and a coating.

[0110] 31. The catalyst according to any one of the preceding embodiments, wherein 0 to 0.1 wt. %, preferably 0 to 0.01 wt. %, and more preferably 0 to 0.001 wt. % of the coating consists of cerium.

[0111] 32. A method for preparing an ammonia oxidation catalyst according to any one of the preceding claims, comprising the steps of: (a) preparing a first mixture comprising water, a selective catalytic reduction component which is a zeolitic material comprising one or more of copper and iron, and preferably a precursor of an oxide binder, more preferably an oxide binder as defined in embodiment 8 or 9; (b) preparing a second mixture comprising water, a source of oxidation catalyst components comprising a source of platinum, a porous non-zeolitic oxide support, and a first oxide material comprising titania; (c) mixing the first mixture obtained in step (a) with the second mixture obtained in step (b); (d) disposing the mixture obtained in step (c) on a substrate, and optionally drying the substrate on which the mixture is disposed; (e) calcining the substrate obtained in step (d). The method includes:

[0112] 33. A process according to claim 1, wherein step (a) comprises the steps of: (a.1) preparing a mixture comprising water and a precursor of an oxide binder, the precursor being preferably one or more of an aluminum salt, a silicon salt, a zirconium salt, and a titanium salt, more preferably one or more of a zirconium salt and an aluminum salt, more preferably a zirconium salt, more preferably zirconium acetate; (a.2) adding a selective catalytic reduction component which is a zeolitic material containing one or more of copper and iron, more preferably an 8 ring pore zeolitic material containing copper, to the mixture resulting from step (a.1). 33. The method of embodiment 32, further comprising:

[0113] 34. Step (b) comprises the steps of: (b.1) impregnating a source of platinum on a porous non-zeolitic oxide support with an adjuvant, the adjuvant preferably being one or more of water and an alcohol, more preferably water; (b.2) impregnating the impregnated porous non-zeolitic oxide support obtained in step (b.1) with a source of one or more platinum group metals, preferably other than platinum; (b.3) impregnating the impregnated porous non-zeolitic oxide support obtained in step (b.1), preferably obtained in step (b.2), with a solution containing a source of a first oxide material comprising titania, preferably a titania hydrogel, to obtain a mixture; (b.4) optionally adding a source of a second oxide material to the mixture obtained in step (b.3); (b.5) drying and / or calcining the mixture obtained in step (b.3), and optionally the mixture obtained in step (b.4), to obtain a powder; (b.6) preparing a mixture comprising water and the powder obtained in step (b.5); (b.7) preferably milling the particles of the mixture obtained in step (b.6), more preferably until the particles of the mixture have a Dv90 in the range of 3 to 30 micrometers, more preferably in the range of 5 to 20 micrometers, more preferably in the range of 8 to 18 micrometers (Dv90 is determined as described in Reference Example 1). Further comprising: The method according to embodiment 32 or 33, wherein step (b) preferably consists of steps (b.1), (b.2), (b.3), (b.5), (b.6) and more preferably (b.7), or wherein step (b) preferably consists of steps (b.1), (b.2), (b.3), (b.4), (b.5), (b.6) and more preferably (b.7).

[0114] 35. The method according to embodiment 34, wherein the impregnation according to step (b.3) is carried out by adding, with stirring, a solution containing a source of the first oxide material to the impregnated porous non-zeolitic oxide support obtained in step (b.1), preferably in step (b.2).

[0115] 36. The method of embodiment 34 or 35, wherein step (b.4) is carried out by adding a source of the second oxide material to the mixture obtained in step (b.3) with stirring.

[0116] 37. The method of any one of embodiments 34 to 36, wherein the source of second oxide material provided in step (b.4) comprises one or more of manganese, cerium, tungsten, molybdenum, praseodymium, europium, chromium, cobalt, technetium, rhenium, ruthenium, vanadium and indium, preferably a source comprising one or more of manganese, cerium, tungsten, praseodymium and indium, more preferably one or more of manganese, cerium and praseodymium, more preferably one or more of manganese and cerium, more preferably a source comprising manganese.

[0117] 38. The method of embodiment 37, wherein the source of the second oxide material provided in step (b.4) is a salt, preferably a nitrate, more preferably manganese nitrate.

[0118] 39. Step (b) comprises the steps of: (b.1') impregnating a source of platinum on a porous non-zeolitic oxide support with an adjuvant, the adjuvant preferably being one or more of water and an alcohol, more preferably water; (b.2') impregnating the impregnated porous non-zeolitic oxide support obtained in step (b.1) with a solution containing a source of a first oxide material comprising titania, preferably a titania hydrogel, to obtain a mixture; (b.3') impregnating a source of one or more platinum group metals other than platinum onto the impregnated porous non-zeolitic oxide support obtained in step (b.2'); (b.4') drying and / or calcining the mixture obtained in step (b.3') to obtain a powder, (b.5') preparing a mixture comprising water and the powder obtained in step (b.4'); (b.6') preferably milling the particles of the mixture obtained in step (b.5'), more preferably until the particles of the mixture have a Dv90 in the range of 3 to 30 micrometers, more preferably in the range of 5 to 20 micrometers, more preferably in the range of 8 to 18 micrometers (Dv90 is determined as described in Reference Example 1). Further comprising: Step (b) preferably comprises steps (b.1'), (b.2'), (b.3'), (b.4'), (b.5') and more preferably (b.6'), The method according to embodiment 32 or 33.

[0119] 40. The method according to embodiment 39, wherein the impregnation according to step (b.2') is carried out by adding a solution containing a source of the first oxide material to the impregnated porous non-zeolitic oxide support obtained in step (b.1') while stirring.

[0120] 41. The method of any one of embodiments 34 to 40, wherein the source of one or more platinum group metals other than platinum provided in step (b.2) or step (b.3') is one or more of a source of rhodium and a source of palladium, preferably one or more of a rhodium nitrate solution and a palladium nitrate solution, more preferably a rhodium nitrate solution.

[0121] 42. The method according to any one of embodiments 34 to 41, wherein the drying according to step (b.5) or step (b.4') is carried out in a gas atmosphere having a temperature in the range of 90 to 160°C, preferably in the range of 110 to 130°C, and the gas atmosphere preferably contains oxygen.

[0122] 43. The method according to any one of embodiments 34 to 42, wherein the calcination according to step (b.5) or (b.4') is carried out in a gas atmosphere having a temperature in the range of 300 to 800 °C, preferably in the range of 400 to 700 °C, and the gas atmosphere preferably contains oxygen.

[0123] 44. The method according to any one of embodiments 34 to 43, wherein the porous non-zeolitic oxide support provided in step (b) comprises pores having an average pore size in the range of 8 to 45 nm, preferably in the range of 10 to 40 nm, more preferably in the range of 12 to 30 nm, more preferably in the range of 15 to 25 nm, the average pore size being determined as described in Reference Example 2.

[0124] 45. The porous non-zeolitic oxide support provided in step (b) has a melting point of 0.6 ml / cm 3 ~2ml / cm 3 in the range of 0.65 ml / cm 3 ~1.75ml / cm 3 More preferably in the range of 0.70 ml / cm 3 ~1.5ml / cm 3 The method according to any one of embodiments 32 to 44, wherein the average pore volume is determined as described in Reference Example 2.

[0125] 46. ​​The porous non-zeolitic oxide support provided in step (b) is 40 to 300 m 2 / g, preferably 50 to 200m 2 / g, more preferably 70 to 160 m 2 The method of any one of embodiments 32 to 45, wherein the BET specific surface area is in the range of 0.1 to 0.1 g / g, the BET specific surface area being determined as described in Reference Example 3.

[0126] 47. The method according to any one of embodiments 32 to 46, wherein 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 porous non-zeolitic oxide support consists of alumina.

[0127] 48. The method according to any one of embodiments 32 to 47, wherein the placing of the mixture obtained in step (c) in step (d) is carried out by spraying the mixture onto the substrate or by immersing the substrate in the mixture, preferably by immersing the substrate in the mixture.

[0128] 49. The method of any one of embodiments 32 to 48, wherein the substrate provided in step (d) has an inlet end, an outlet end, a substrate axial length extending from the inlet end to the outlet end, and a plurality of passages defined by an inner wall of the substrate extending through the substrate, the interface between the passages and the inner wall defining a surface of the inner wall.

[0129] 50. The method of embodiment 49, wherein the mixture obtained in step (c) is disposed by step (d) from the inlet end to the outlet end over 95 to 100%, preferably over 98 to 100%, more preferably over 99 to 100% of the axial length of the substrate.

[0130] 51. The substrate provided in step (d) is a flow-through substrate or a wall-flow filter substrate, preferably a flow-through substrate; the substrate provided in step (d) is preferably a ceramic substrate, the substrate more preferably comprises, more preferably consists of, one or more of cordierite, aluminium titanate, mullite and silicon carbide, more preferably one or more of cordierite, aluminium titanate and silicon carbide, more preferably cordierite, the substrate more preferably being a cordierite flow-through substrate; or 51. The method of any one of embodiments 32 to 50, wherein the substrate provided in step (d) preferably comprises, more preferably consists of, a metal material, the metal material preferably comprises, more preferably consists of, oxygen and one or more of iron, chromium and aluminium, and the substrate is more preferably a metallic flow-through substrate.

[0131] 52. The method according to any one of embodiments 32 to 51, wherein the drying according to step (d) is carried out in a gas atmosphere having a temperature in the range of 90 to 180° C., preferably in the range of 110 to 130° C., and the gas atmosphere preferably contains oxygen.

[0132] 53. The method according to any one of embodiments 32 to 52, wherein the drying according to step (d) is carried out in a gas atmosphere for a duration in the range of 10 to 300 minutes, preferably in the range of 60 to 120 minutes, the gas atmosphere preferably comprising oxygen.

[0133] 54. The method according to any one of embodiments 32 to 53, wherein the calcination according to step (e) is carried out in a gas atmosphere having a temperature in the range of 300 to 800° C., preferably in the range of 450 to 650° C., and the gas atmosphere preferably contains oxygen.

[0134] 55. The method according to any one of embodiments 32 to 54, wherein the calcination according to step (e) is carried out in a gas atmosphere for a duration in the range of 10 to 300 minutes, preferably in the range of 60 to 120 minutes, and the gas atmosphere preferably contains oxygen.

[0135] 56. Further steps: (f) ageing the product obtained in step (e) in a gas atmosphere, more preferably in a gas atmosphere having a temperature in the range of 600-900°C, more preferably in the range of 700-800°C, the gas atmosphere more preferably containing oxygen. 55. The method of any one of embodiments 32 to 54, comprising:

[0136] 57. A method according to any one of embodiments 32 to 56, comprising steps (a), (b), (c), (d) and (e), or comprising steps (a), (b), (c), (d), (e) and (f).

[0137] 58. An ammonia oxidation catalyst obtained or obtainable by the method according to any one of embodiments 32 to 57, preferably 57.

[0138] 59. A method of using the ammonia oxidation catalyst according to any one of embodiments 1 to 31 and 58 for the oxidation of ammonia, wherein the ammonia is preferably contained in an exhaust gas stream from a diesel engine.

[0139] 60. A process for oxidizing ammonia contained in an exhaust gas stream, comprising: (1) providing said exhaust gas stream, preferably from a diesel engine; (2) passing the exhaust gas stream provided in step (1) through a catalyst according to any one of embodiments 1 to 31 and 58. A method comprising:

[0140] 61. The catalyst according to any one of embodiments 1 to 31 and 58 is subjected to the following steps: (i) heating the catalyst in a gas atmosphere at a temperature in the range of 700-800° C. for a duration in the range of 10-20 hours, the gas atmosphere preferably containing 5-15% steam; An aged catalyst obtainable or obtained by a process comprising, preferably consisting of, subjecting the catalyst to an ageing treatment comprising, preferably consisting of, The aged catalyst comprises platinum supported on a porous non-zeolitic oxide support exhibiting an average crystallite size in the range of 5-100 nm, preferably 10-30 nm, more preferably 12-28 nm, more preferably 14-25 nm, wherein the average crystallite size is determined as described in Reference Example 10.

[0141] In the present invention, the term "internal wall surface" is to be understood as the "bare" or "bare" or "blank" surface of the wall, i.e. the surface of the wall in its untreated state consisting of the wall material, except for unavoidable impurities that may contaminate the surface.

[0142] Furthermore, in the present invention, the term "X is one or more of A, B, and C" is understood as disclosing either that X is A, or B, or C, or A and B, or A and C, or B and C, or A and B and C, where X is a given feature and each of A, B, and C represents a specific realization of said feature. In this regard, it should be noted that a person skilled in the art can translate the above abstract terms into concrete examples, such as when X is a chemical element and A, B, and C are specific elements such as Li, Na, and K, or when X is a temperature and A, B, and C are specific temperatures such as 10°C, 20°C, and 30°C. In this regard, it is further noted that a person skilled in the art can expand the above terminology from a less specific realization of said feature, e.g., "X is one or more of A and B," which discloses either X is A, or B, or A and B, to a more specific realization of said feature, e.g., "X is one or more of A, B, C, and D," which discloses either X is A, or B, or C, or D, or A and B, or A and C, or A and D, or B and C, or B and D, or C and D, or A and B and C, or A and B and D, or B and C and D, or A and B and C and D.

[0143] Furthermore, in the present invention, the term "consisting of" in relation to the weight percent of one or more components refers to the weight percent amount of said component(s) based on 100 weight percent of the whole of the object. For example, the phrase "0-0.01 weight percent of the coating consists of cerium" indicates that 0-0.01 weight percent of cerium is 100 weight percent of the components constituting said coating.

[0144] The present invention is further illustrated by the following Examples, Reference Examples and Comparative Examples. EXAMPLES

[0145] Reference Example 1: Determination of volumetric pore size distribution (Dv90) The particle size distribution was determined by static light scattering method using a Sympatec HELOS (3200) & QUIXEL instrument, and the optical density of the samples was in the range of 6–10%.

[0146] Reference Example 2: Determination of the average pore volume and average pore diameter of the porous oxide support This was determined by Barrett-Joyner-Halenda (BJH) analysis, a method for determining pore size distribution that is typically applied to nitrogen desorption data measured at 77 K for mesoporous materials. It is a method for determining the ... mesoporous materials at 77 K for nitrogen desorption data measured at 77 K for mesoporous 0 A modified Kelvin equation is used to relate the amount of adsorbate removed from the pores of a material to the pore size as the pore size decreases from a high to a low value.

[0147] Reference Example 3: BET surface area measurement The BET specific surface area was determined using liquid nitrogen in accordance with DIN 66131 or DIN-ISO 9277.

[0148] Reference Example 4: Common Coating Methods To coat a flow-through substrate with one or more coatings, a portion of a given slurry was dipped vertically along a specific length of the substrate. In this way, the washcoat was in contact with the walls of the substrate. The sample was left in the slurry for a period of time (usually 1-10 seconds). A vacuum was applied to draw the slurry into the substrate. The substrate was then removed from the slurry and inverted to allow excess slurry to drain from the substrate, after which it was removed from the substrate by blowing compressed air (against the direction of penetration of the slurry) through it.

[0149] Reference Example 5: Preparation of oxidation catalyst Pt / Rh-alumina suspension In a container, 10 g of a platinum amine salt solution (containing 17 wt. % Pt) was mixed with 100 ml of deionized water. This mixture was mixed with 716 g of alumina powder (ZrO 2 Al doped with 20 mass% Zr, calculated as 2 O 3 , BET specific surface area 200m 2 / g, pore volume 0.4ml / cm 3 , average pore size 5 nanometers). Subsequently, 33 ml of rhodium-nitrate solution (containing 10 wt. % Rh based on the weight of the solution) was added dropwise to the resulting platinum-alumina mixture. The resulting mixture was then calcined in a box oven at 600°C for 2 hours in air. The calcined powder was added to 4.5 kg of deionized water to obtain a suspension. The suspension was then ball milled to obtain a suspension with a Dv90 of 15 micrometers for the particles. An uncoated honeycomb flow-through ceramic monolith substrate (Cordierite - a cylindrical substrate with a diameter of 2.54 cm (1 inch) by length of 10.16 cm (4 inches) with a pore size of 400 / (2.54) per square centimeter was used. 2 A 100% sintered substrate (having 10 cells and a wall thickness of 0.1 millimeters (4 mils)) was dip coated with the resulting suspension over 100% of the substrate's length according to the method described in Reference Example 4. The coated substrate was dried at 120° C. for 2 hours and calcined at 600° C. in air for 2 hours. The final loading of the coating on the catalyst after calcination was about 0.25 g / in 3 which includes 0.25 g / in 3 Alumina-Zr, 3g / ft 3 of Pt, and 2g / ft 3 The Pt:Rh atomic ratio was 1.5:1.

[0150] Reference Example 6: Preparation of oxidation catalyst Pt / Rh-alumina suspension In a container, 10 g of a platinum amine salt solution (containing 17 wt % Pt) was mixed with 100 ml of deionized water. This mixture was mixed with 716 g of alumina powder (BET specific surface area 100 m 2 / g, average pore volume approx. 1ml / cm 3, average pore size 20 nanometers). 33 ml of rhodium-nitrate solution (containing 10 wt. % Rh) was then added dropwise to the resulting platinum-alumina mixture. The resulting mixture was then calcined in a box oven at 600°C for 2 hours in air. The calcined powder was added to deionized water to obtain a suspension. The suspension was then ball milled to obtain a suspension with a Dv90 of 15 micrometers for the particles. An uncoated honeycomb flow-through ceramic monolith substrate (cordierite - a cylindrical substrate with a diameter of 2.54 cm (1 inch) x length of 10.16 cm (4 inches) with a pore size of 400 / (2.54) per square centimeter was used. 2 A 100% sintered substrate (having 10 cells and a wall thickness of 0.1 millimeters (4 mils)) was dip coated with the resulting suspension over 100% of the substrate's length according to the method described in Reference Example 4. The coated substrate was dried at 120° C. for 2 hours and calcined at 600° C. in air for 2 hours. The final loading of the coating on the catalyst after calcination was about 0.25 g / in 3 which includes 0.25 g / in 3 of alumina, 3 g / ft 3 of Pt, and 2g / ft 3 The Pt:Rh atomic ratio was 1.5:1.

[0151] Reference Example 7 Preparation of oxidation catalyst Pt / Rh-alumina suspension In a container, 10 g of a platinum amine salt solution (containing 17 wt % Pt) was mixed with 100 ml of deionized water. This mixture was mixed with 716 g of alumina powder (BET specific surface area 100 m 2 / g, average pore volume approx. 1ml / cm 3 33 ml of rhodium-nitrate solution (containing 10% by weight of Rh) was then added dropwise onto the Pt-alumina mixture. 200 g of TiO 2 Hydrogel (18 wt.% TiO based on the weight of the hydrogel) 2(containing 1.0 g of 1.5% MnO) was added dropwise to the Pt / Rh-alumina mixture while vigorously mixing using an Eirich mixer. Then, 60 g of manganese nitrate solution (having 50% Mn content by weight, calculated as MnO, based on the weight of the solution) was added dropwise while vigorously mixing. The resulting mixture was dried at 120°C for 2 hours and then calcined in a box oven at 600°C for 2 hours in air to obtain a powder. The calcined powder was added to 4.5 kg of deionized water. The resulting suspension was then ball milled to obtain a suspension with a Dv90 of 15 micrometers for the particles. An uncoated honeycomb flow-through ceramic monolith substrate (cordierite - a cylindrical substrate with a diameter of 2.54 cm (1 inch) x length of 10.16 cm (4 inches) and a 400 / (2.54) per square centimeter powder was added. 2 A 100% sintered substrate (having 10 cells and a wall thickness of 0.1 millimeters (4 mils)) was dip coated with the resulting suspension over 100% of the substrate's length according to the method described in Reference Example 4. The coated substrate was dried at 120° C. for 2 hours and calcined at 600° C. in air for 2 hours. The final loading of the coating on the catalyst after calcination was about 0.27 g / in 3 which includes 0.25 g / in 3 of alumina, 0.0125 g / in 3 of titania, 0.01g / in 3 MnO, 3g / ft 3 of Pt, and 2g / ft 3 The Pt:Rh atomic ratio was 1.5:1.

[0152] Reference Example 8 Preparation of oxidation catalyst Pt / Rh-alumina suspension In a separate container, 10 g of a platinum amine salt solution (containing 17 wt. % Pt) was mixed with 100 ml of deionized water. This mixture was mixed with 716 g of alumina powder (BET specific surface area 100 m 2 / g, average pore volume approx. 1ml / cm 3 Then, 200 g of TiO 2 Hydrogel (18 wt.% TiO based on the weight of the hydrogel)2 A solution of 33 ml of rhodium-nitrate solution (containing 10% by weight Rh based on the weight of the solution) was added dropwise to the Pt-alumina mixture under vigorous mixing. Then, 33 ml of rhodium-nitrate solution (containing 10% by weight Rh based on the weight of the solution) was added dropwise to the resulting mixture. The mixture was dried at 120°C for 2 hours and then calcined in a box oven at 600°C for 2 hours in air to obtain a powder. The calcined powder was added to 4.5 kg of deionized water. The resulting suspension was then ball milled to obtain a suspension with a Dv90 of 15 micrometers for the particles. An uncoated honeycomb flow-through ceramic monolith substrate (Cordierite - a cylindrical substrate with a diameter of 2.54 cm (1 inch) x length of 10.16 cm (4 inches) with a surface roughness of 400 / (2.54) per square centimeter was used. 2 A 100% sintered substrate (having 10 cells and a wall thickness of 0.1 millimeters (4 mils)) was dip coated with the resulting suspension over 100% of the substrate's length according to the method described in Reference Example 4. The coated substrate was dried at 120° C. for 2 hours and calcined at 600° C. in air for 2 hours. The final loading of the coating on the catalyst after calcination was about 0.26 g / in 3 which includes 0.25 g / in 3 of alumina, 0.0125 g / in 3 of titania, 3g / ft 3 of Pt, and 2g / ft 3 The Pt:Rh atomic ratio was 1.5:1.

[0153] Reference Example 9 Preparation of oxidation catalyst Pt / Rh-alumina suspension In a separate container, 10 g of a platinum amine salt solution (containing 17 wt. % Pt) was mixed with 100 ml of deionized water. This mixture was mixed with 716 g of alumina powder (BET specific surface area 100 m 2 / g, average pore volume approx. 1ml / cm 3 33 ml of rhodium-nitrate solution (containing 10% by weight Rh based on the weight of the solution) was then added dropwise onto the Pt-alumina mixture. Then, 200 g of TiO 2Hydrogel (18 wt.% TiO based on the weight of the hydrogel) 2 The Pt / Rh-alumina mixture was added dropwise with vigorous mixing. The resulting mixture was dried at 120°C for 2 hours and then calcined in a box oven in air at 600°C for 2 hours. The calcined powder was added to 4.5 kg of deionized water. The resulting suspension was then ball milled to ensure that the suspension particles had a Dv90 of 15 micrometers. An uncoated honeycomb flow-through ceramic monolith substrate (Cordierite - a cylindrical substrate with a diameter of 2.54 cm (1 inch) x length of 10.16 cm (4 inches) with a 400 / (2.54) per square centimeter cross section) was used. 2 A 100% sintered substrate (having 10 cells and a wall thickness of 0.1 millimeters (4 mils)) was dip coated with the resulting suspension over 100% of the substrate's length according to the method described in Reference Example 4. The coated substrate was dried at 120° C. for 2 hours and calcined at 600° C. in air for 2 hours. The final loading of the coating on the catalyst after calcination was about 0.26 g / in 3 which includes 0.25 g / in 3 of alumina, 0.0125 g / in 3 of titania, 3g / ft 3 of Pt, and 2g / ft 3 The Pt:Rh atomic ratio was 1.5:1.

[0154] Comparative Example 1: Preparation of AMOX catalyst not according to the invention a) Zeolite suspension 0.7 kg of the zirconium acetate solution was mixed with 5.2 kg of deionized water in a container. To this mixture was added 5.0 kg of Cu-SSZ-13 zeolite material (Cu content is 3.3 wt. %, calculated as CuO, based on the weight of the zeolite material, SiO 2 :Al 2 O 3 Molar ratio is 25, BET specific surface area is about 500-600m 2 / g, and Dv90 of 5 micrometers). b) Pt / Rh-alumina suspension The suspension was prepared as the Pt / Rh-alumina suspension prepared in Reference Example 5. c) Final Suspension Furthermore, the Pt / Rh-alumina suspension obtained in b) was added to the zeolite suspension obtained in a) and mixed thoroughly.

[0155] Uncoated honeycomb flow-through ceramic monolith substrate (Cordierite - 1 in. diameter x 4 in. length cylindrical substrate with 400 / (2.54) per square centimeter 2 A 100% SiO2 catalyst having 10 cells and a wall thickness of 0.1 millimeters (4 mils) was dip coated with the final suspension over 100% of the substrate's length according to the method described in Reference Example 4. The coated substrate was dried at 120° C. for 2 hours and calcined at 590° C. in air for 2 hours. The final loading of the coating on the catalyst after calcination was about 2 g / in 3 which includes 1.65g / in 3 Cu-SSZ-13, 0.25 g / in 3 Alumina-Zr, 0.1g / in 3 of zirconia, 3g / ft 3 Pt and 2g / ft 3 The Pt:Rh atomic ratio was 1.5:1.

[0156] Comparative Example 2: Preparation of AMOX catalyst not according to the invention Cu-SSZ-13 zeolite material (Cu content calculated as CuO is 4.5 wt.% based on the weight of the zeolite material, SiO 2 :Al 2 O 3 Molar ratio is 25, BET specific surface area is about 500-600m 2 The catalyst of Comparative Example 2 was prepared in the same manner as the catalyst of Comparative Example 1, except that a 100% cellulose ester having a molecular weight of 1.0 kg / g and a Dv90 of 5 micrometers was used.

[0157] Comparative Example 3: Preparation of AMOX catalyst not according to the invention Cu-SSZ-13 zeolite material (Cu content calculated as CuO is 5.5 wt.% based on the weight of the zeolite material, SiO 2 :Al 2 O 3 Molar ratio is 18, BET specific surface area is about 500-600m 2 The catalyst of Comparative Example 3 was prepared in the same manner as the catalyst of Comparative Example 1, except that a 100% cellulose ester having a molecular weight of 1.0 kg / g and a Dv90 of 5 micrometers was used.

[0158] Comparative Example 4: Preparation of AMOX catalyst not according to the invention a) Zeolite suspension 0.7 kg of the zirconium acetate solution was mixed with 5.2 kg of deionized water in a container. To this mixture was added 5.0 kg of Cu-SSZ-13 zeolite material (Cu content is 5.5 wt. %, calculated as CuO, based on the weight of the zeolite material, SiO 2 :Al 2 O 3 Molar ratio is 18, BET specific surface area is about 500-600m 2 / g, and Dv90 of 5 micrometers). b) Pt / Rh-alumina suspension The suspension was prepared as the Pt / Rh-alumina suspension prepared in Reference Example 6. c) Final Suspension Furthermore, the Pt / Rh-alumina suspension obtained in b) was added to the zeolite suspension obtained in a) and mixed thoroughly.

[0159] Uncoated honeycomb flow-through ceramic monolith substrate (Cordierite - 1 in. diameter x 4 in. length cylindrical substrate with 400 / (2.54) per square centimeter 2 A 100% SiO2 catalyst having 10 cells and a wall thickness of 0.1 millimeters (4 mils) was dip coated with the final suspension over 100% of the substrate's length according to the method described in Reference Example 4. The coated substrate was dried at 120° C. for 2 hours and calcined at 600° C. in air for 2 hours. The final loading of the coating on the catalyst after calcination was about 2 g / in 3which includes 1.65g / in 3 Cu-SSZ-13, 0.25 g / in 3 of alumina, 0.1 g / in 3 of zirconia, 3g / ft 3 Pt and 2g / ft 3 The Pt:Rh atomic ratio was 1.5:1.

[0160] Example 1: Preparation of AMOX catalyst a) Zeolite suspension 0.7 kg of the zirconium acetate solution was mixed with 5.2 kg of deionized water in a container. To this mixture was added 5.0 kg of Cu-SSZ-13 zeolite material (Cu content is 5.5 wt. %, calculated as CuO, based on the weight of the zeolite material, SiO 2 :Al 2 O 3 Molar ratio is 18, BET specific surface area is about 500-600m 2 / g, and Dv90 of 5 micrometers). b) Pt / Rh-alumina suspension The suspension was prepared as the Pt / Rh-alumina suspension prepared in Reference Example 7. c) Final Suspension Furthermore, the Pt / Rh-alumina suspension obtained in b) was added to the zeolite suspension obtained in a) and mixed thoroughly.

[0161] Uncoated honeycomb flow-through ceramic monolith substrate (Cordierite - 1 in. diameter x 4 in. length cylindrical substrate with 400 / (2.54) per square centimeter 2 A 100% SiO2 catalyst having 10 cells and a wall thickness of 0.1 millimeters (4 mils) was dip coated with the final suspension over 100% of the substrate's length according to the method described in Reference Example 4. The coated substrate was dried at 120° C. for 2 hours and calcined at 600° C. in air for 2 hours. The final loading of the coating on the catalyst after calcination was about 2 g / in 3 which includes 1.65g / in 3Cu-SSZ-13, 0.25 g / in 3 of alumina, 0.0125 g / in 3 of titania, 0.01g / in 3 MnO, 0.1g / in 3 of zirconia, 3g / ft 3 Pt and 2g / ft 3 The Pt:Rh atomic ratio was 1.5:1.

[0162] Example 2: Preparation of AMOX catalyst a) Zeolite suspension The suspension was prepared as a zeolite suspension as prepared in Example 1 a). b) Pt / Rh-alumina suspension The suspension was prepared as the Pt / Rh-alumina suspension prepared in Reference Example 8. c) Final Suspension Additionally, the Pt / Rh / alumina suspension was added to the zeolite suspension and mixed thoroughly.

[0163] Uncoated honeycomb flow-through ceramic monolith substrate (Cordierite - 1 in. diameter x 4 in. length cylindrical substrate with 400 / (2.54) per square centimeter 2 A 100% SiO2 catalyst having 10 cells and a wall thickness of 0.1 millimeters (4 mils) was dip coated with the final suspension over 100% of the substrate's length according to the method described in Reference Example 4. The coated substrate was dried at 120° C. for 2 hours and calcined at 600° C. in air for 2 hours. The final loading of the coating on the catalyst after calcination was about 2 g / in 3 which includes 1.65g / in 3 Cu-SSZ-13, 0.25 g / in 3 of alumina, 0.0125 g / in 3 of titania, 0.1g / in 3 of zirconia, 3g / ft 3 Pt and 2g / ft 3 The Pt:Rh atomic ratio was 1.5:1.

[0164] Example 3: Preparation of AMOX catalyst a) Zeolite suspension The suspension was prepared as a zeolite suspension as prepared in Example 1 a). b) Pt / Rh-alumina suspension The suspension was prepared as the Pt / Rh-alumina suspension prepared in Reference Example 9. c) Final Suspension Furthermore, the Pt / Rh-alumina suspension was added to the zeolite suspension obtained in a) and mixed thoroughly.

[0165] Uncoated honeycomb flow-through ceramic monolith substrate (Cordierite - 1 in. diameter x 4 in. length cylindrical substrate with 400 / (2.54) per square centimeter 2 A 100% SiO2 catalyst having 10 cells and a wall thickness of 0.1 millimeters (4 mils) was dip coated with the final suspension over 100% of the substrate's length according to the method described in Reference Example 4. The coated substrate was dried at 120° C. for 2 hours and calcined at 600° C. in air for 2 hours. The final loading of the coating on the catalyst after calcination was about 2 g / in 3 which includes 1.65g / in 3 Cu-SSZ-13, 0.25 g / in 3 of alumina, 0.0125 g / in 3 of titania, 0.1g / in 3 of zirconia, 3g / ft 3 Pt and 2g / ft 3 The Pt:Rh atomic ratio was 1.5:1.

[0166] Reference Example 10: Measurement of average platinum group metal (PGM) crystallite size The average platinum group metal (PGM) crystallite size was measured according to the method disclosed in application WO2015 / 143191A1, see in particular

[0064] to

[0075] of the same application.

[0167] Reference Example 4: Performance Test The catalysts of Reference Examples 4-8, Comparative Examples 1-4, and Examples 1-3 were tested. The catalysts were aged at 750°C with 10% steam for 16 hours. The tests were carried out using a laboratory reactor consisting of a heated tube containing test samples measuring 1 inch in diameter and 4 inches in length. The feed gas concentration was N 2 NH in 3 220 ppm, CO 2 5% and O 2 15%, and the space velocity is 90k h -1 The gas and sample temperatures were set to 150°C. The test was carried out for 10 minutes under these conditions (heating from 150 to 550°C - SV = 80k h -1 , 225 ppm NH 3 , 12% O 2 , 4% H 2 O, 4% CO 2 After this and 30 min at 150° C., a further 150 ppm NO was fed into the gas and the temperature was set to increase by 30° C. / min until it reached 550° C. (SV=80 k h -1 , 225 ppm NH 3 , 150 ppm NO, 12% O 2 , 4% H 2 O, 4% CO 2 During this test, inlet and outlet concentrations were measured using FTIR. NOx conversion was calculated as follows: NOx conversion (%) = ((NOx outlet (ppm) / (NOx inlet (ppm))-1)*100.

[0168] The results are shown in Table 1 below and in FIG.

[0169] [Table 1]

[0170] * The PGM average crystallite size was determined as described in Reference Example 10. ** T50[NH 3 ](with zeolite)-T50[NH 3](without zeolite) a Cu-SSZ-13: Cu-SiO with 3.3% by mass calculated as CuO 2 :Al 2 O 3 Molar ratio 25 b Cu-SSZ-13: Cu-SiO with 4.5% by mass calculated as CuO 2 :Al 2 O 3 Molar ratio 18 c Cu-SSZ-13: 5.5% by mass Cu-SiO calculated as CuO 2 :Al 2 O 3 Molar ratio 18

[0171] As can be seen from Table 1, the lowest increase in ammonia light-off temperature was achieved for the catalysts of Examples 1-3 containing titania supported on porous alumina. This effect is more pronounced for the catalyst of Example 1, which contains MnO in addition to titania. Furthermore, lower NOx formation was observed for the catalysts of Examples 1-3 containing titania supported on porous alumina, compared to the catalysts of Comparative Examples 1-4, which do not contain titania or MnO. Finally, the application of Pt, Rh and TiO to the porous support 2 It is also believed that the order of impregnation of the ammonia affects the light temperature of the ammonia. In particular, first impregnating the alumina with Pt and then the TiO 2 The catalyst of Example 2, impregnated with Pt, then Rh, and finally TiO, showed a difference in light-off temperature of 37° C., whereas the catalyst of Example 2, impregnated first with Pt, then with Rh, and finally with TiO, showed a difference in light-off temperature of 37° C. 2 The catalyst of Example 3 impregnated with 27°C reduced light-off temperature difference was obtained. As a result, the catalysts of Examples 1 to 3 according to the present invention show higher selectivity than the catalysts of Comparative Examples 1 to 4. The catalyst of the present invention can reduce the formation of NOx and nitrous oxide.

[0172] Finally, from Table 1, without being bound by any theory, it is believed that titania, when impregnated onto a porous non-zeolitic oxide support already carrying platinum (and optionally rhodium), can reduce the interaction of platinum and copper in the coating of the catalyst of the invention, and indeed this is supported by the improvement in NOx conversion obtained with the catalyst according to the invention.

[0173] Reference Example 11: Preparation of oxidation catalyst Porous alumina powder (BET specific surface area 100m 2 / g, average pore volume approx. 1ml / cm 3 , with an average pore size of 20 nm) was used as a porous alumina powder (BET specific surface area of ​​150 m 2 / g, average pore volume approx. 0.9 ml / cm 3 The catalyst of Reference Example 11 was prepared in the same manner as the catalyst of Reference Example 9, except that the catalyst was replaced with 18 nm average pore diameter-96% solids.

[0174] Reference Example 12: Preparation of oxidation catalyst Pt / Rh-alumina suspension 101 g of a ZrO solution with a solid content of 30 mass % was added to 395 g of porous gamma alumina powder (BET specific surface area 150 m 2 / g, average pore volume 0.9ml / cm 3 The powder was then calcined in an oven at 650° C. for 4 hours under air.

[0175] 12.8 g of platinum monoethanolic solution (containing 16 wt.% Pt) was mixed with 100 mg of deionized water. This mixture was added dropwise to the resulting Zr-doped alumina powder with vigorous stirring. Then, 15.2 g of rhodium nitrate solution (containing 9.6 wt.% Rh) was diluted with 100 g of deionized water and added dropwise to the resulting platinum / Zr-doped alumina mixture with stirring.

[0176] The resulting mixture was dried at 120°C for 2 h and then calcined in a box oven at 600°C for 2 h in air. The calcined powder was added to deionized water (1 kg) to obtain a suspension. The suspension was then ball milled to obtain a Dv90 of 10 micrometers for the particles in the suspension.

[0177] Uncoated honeycomb flow-through ceramic monolith substrate (Cordierite - 1 in. diameter x 4 in. length cylindrical substrate with 400 / (2.54) per square centimeter 2 A 100% sintered substrate (having 10 cells and a wall thickness of 0.1 millimeters (4 mils)) was dip coated with the resulting suspension over 100% of the substrate's length according to the method described in Reference Example 4. The coated substrate was dried at 120° C. for 2 hours and calcined at 600° C. in air for 2 hours. The final loading of the coating on the catalyst after calcination was about 0.25 g / in 3 which includes 0.25 g / in 3 Zr-alumina (ZrO 2 8% Zr by weight based on the weight of alumina), 3 g / ft 3 Pt and 2g / ft 3 The Pt:Rh atomic ratio was 1.5:1.

[0178] Reference Example 13: Preparation of oxidation catalyst Pt / Rh-alumina suspension TiO with a solid content of 18.5% by mass 2 162 g of the sol-gel was mixed with 395 g of porous gamma alumina powder (BET specific surface area 150 m 2 / g, average pore volume 0.9ml / cm 3 , and average pore size 18 nm - solid content 96%) was added dropwise under vigorous stirring. The powder was then calcined in an oven at 650 °C under air for 4 h.

[0179] 12.8 g of platinum monoethanolic solution (containing 16 wt.% Pt) was mixed with 100 mg of deionized water. This mixture was added dropwise to the resulting Ti-doped alumina powder with vigorous stirring. Then, 15.2 g of rhodium nitrate solution (containing 9.6 wt.% Rh) was diluted with 100 g of deionized water and added dropwise to the resulting platinum / Ti-doped alumina mixture with stirring.

[0180] The resulting mixture was dried at 120°C for 2 hours and then calcined in a box oven in air at 600°C for 2 hours. The calcined powder was added to deionized water (1 kg) to obtain a suspension. The suspension was then ball milled to obtain a Dv90 of 10 micrometers for the particles in the suspension.

[0181] Uncoated honeycomb flow-through ceramic monolith substrate (Cordierite - 1 in. diameter x 4 in. length cylindrical substrate with 400 / (2.54) per square centimeter 2 A 4 mil (0.1 millimeter (4 mil)) 100% long substrate having 100% of its length was dip coated with the resulting suspension according to the method described in Reference Example 4. The coated substrate was dried at 120° C. for 2 hours and calcined at 600° C. in air for 2 hours. The final loading of the coating on the catalyst after calcination was about 0.25 g / in. 3 which includes 0.25 g / in 3 Ti-alumina (TiO 2 (8% Ti by weight, calculated based on the weight of alumina), 3 g / ft 3 of Pt, and 2g / ft 3 The Pt:Rh atomic ratio was 1.5:1.

[0182] Reference Example 14: Performance Testing The catalysts of Reference Examples 5 and 11-13 were tested. The catalysts were aged at 750°C for 16 hours with 10% steam in air and NH 3 The light-off test was performed. In this test, 750 ppm NH 3, 12% CO 2 , 4% O 2 and 4% H 2 O, space velocity (SV) 100 k h -1 The catalyst was NH 3 After full saturation with NH, the temperature was increased to 550 °C at a rate of 5 °C / min. 3 The temperature at which 50% of N was converted was recorded and shown in Table 2 for different catalysts and N 2 The O peak emissions were plotted.

[0183] [Table 2]

[0184] As can be seen from Table 2, the catalyst of Reference Example 11 containing titania supported on porous alumina already supporting Pt and Rh had the lowest nitrous oxide emissions compared to the catalysts of Reference Examples 5 and 12 not containing titania. Furthermore, the catalyst of Reference Example 11 containing titania supported on porous alumina already supporting Pt and Rh also had the lowest nitrous oxide emissions while maintaining the ammonia light-off temperature compared to the catalyst of Reference Example 13 containing Pt and Rh supported on Ti-doped alumina. In fact, when the catalyst of Reference Example 11 was used, the nitrous oxide emissions were reduced by about 64% compared to the catalyst of Reference Example 13, while the ammonia light-off showed a 20% increase. Thus, it is believed that not only the presence of titania in the catalyst, but also the position of titania on the porous alumina in view of the other components of the catalyst, affect the performance of the catalyst.

[0185] References - WO2010 / 062730A2 - EP2878360A1 - WO2015 / 143191A1

Claims

1. (i) a selective catalytic reduction component that is a zeolitic material containing one or more of copper and iron; and (ii) an oxidation catalyst component comprising platinum supported on a porous non-zeolitic oxide support, further comprising a first oxide material supported on said porous non-zeolitic oxide support supporting platinum, said first oxide material comprising titania; disposed on a substrate, a coating comprising: the porous non-zeolitic oxide support comprises one or more of alumina, zirconia-alumina, silica-alumina, and mixtures of two or more thereof; and An ammonia oxidation catalyst for treating an exhaust gas stream, wherein said oxidation catalyst component further comprises rhodium.

2. The selective catalytic reduction component according to (i) is an 8-ring pore zeolitic material, the 8-ring pore zeolitic material having a framework type selected from the group consisting of CHA, AEI, RTH, LEV, DDR, KFI, ERI, AFX, mixtures of two or more thereof, and mixed types of two or more thereof; 2. The catalyst of claim 1, wherein the zeolitic material comprises copper, and the amount of copper in the zeolitic material, calculated as CuO, is in the range of 0.1 to 10% by weight, based on the total weight of the zeolitic material.

3. The coating further comprises an oxide binder, the oxide binder comprising: Zirconia, alumina, titania, silica, and A mixed oxide containing two or more of Zr, Al, Ti and Si. and 3. The catalyst of claim 1 or 2, wherein the coating comprises the oxide binder in an amount ranging from 1 to 10% by weight, based on the total weight of the zeolitic material.

4. 4. A catalyst according to any one of claims 1 to 3, wherein from 65 to 95% by weight of said oxidation catalyst component consists of said porous non-zeolitic oxide support.

5. the porous non-zeolitic oxide support comprises alumina; 5. A catalyst according to any one of claims 1 to 4, wherein 95 to 100% by weight of the porous non-zeolitic oxide support consists of alumina.

6. 6. The catalyst according to any one of claims 1 to 5, wherein the coating comprises the selective catalytic reduction component (i) in a loading (l1) and the porous non-zeolitic oxide support in a loading (l3), the loading ratio of the selective catalytic reduction component (i) to the porous non-zeolitic oxide support, expressed as (l1):(l3), being in the range of 1:1 to 25:

1.

7. the coating comprises platinum in an amount in the range of 0.2 to 1.5% by weight, calculated as elemental platinum, based on the weight of the porous non-zeolitic oxide support; The coating provides a platinum loading in the catalyst of 0.5 to 25 g / ft, calculated as elemental platinum. ３ (17.657~882.868g / m ３ 7. The catalyst according to claim 1 , wherein the molar ratio of the catalyst is in the range of 0.1 to 0.

5.

8. The coating contains from 0.5 to 20 g / ft rhodium, calculated as elemental platinum group metal. ３ (17.657~706.294g / m ３ 8. The catalyst of claim 1 , wherein the amount of the catalyst supported is in the range of 0.1 to 1.

0.

9. 9. A catalyst according to any one of claims 1 to 8, wherein the coating comprises the first oxide material in an amount in the range of 1 to 20% by weight, based on the weight of the porous non-zeolitic oxide support.

10. the oxidation catalyst component further comprises a second oxide material supported on the porous non-zeolitic oxide support, the second oxide material comprising one or more of manganese, cerium, tungsten, molybdenum, praseodymium, europium, chromium, cobalt, technetium, rhenium, ruthenium, vanadium and indium; 10. The catalyst of any one of claims 1 to 9, wherein the coating comprises the second oxide material in an amount in the range of 1 to 20% by weight, based on the weight of the porous non-zeolitic oxide support.

11. A method for preparing the ammonia oxidation catalyst according to any one of claims 1 to 10, comprising the steps of: (a) preparing a first mixture comprising water and the selective catalytic reduction component, the zeolitic material comprising one or more of copper and iron; (b) preparing a second mixture comprising water, a source of said oxidation catalyst components comprising a source of platinum, said porous non-zeolitic oxide support, and said first oxide material comprising titania, the porous non-zeolitic oxide support comprises one or more of alumina, zirconia-alumina, silica-alumina, and mixtures of two or more thereof; The oxidation catalyst component further comprises rhodium; and Step (b) comprises the steps of: (b.1) impregnating the source of platinum into the porous non-zeolitic oxide support using a solvent; preparing a second mixture, (c) mixing the first mixture obtained in step (a) with the second mixture obtained in step (b); (d) disposing the mixture obtained in step (c) on a substrate, and optionally drying the substrate on which the mixture is disposed; (e) calcining the substrate obtained in step (d).

12. Step (a) comprises the steps of: (a.1) preparing a mixture comprising water and a precursor of an oxide binder, the precursor being one or more of an aluminum salt, a silicon salt, a zirconium salt, and a titanium salt; (a.2) adding the selective catalytic reduction component, which is the zeolitic material containing one or more of copper and iron, to the mixture obtained in step (a.1). The method of claim 11 further comprising:

13. Step (b) comprises the steps of: (b.3) impregnating the impregnated porous non-zeolitic oxide support obtained in step (b.1) with a solution containing a source of said first oxide material comprising titania to obtain a mixture; (b.4) optionally adding a source of a second oxide material to the mixture obtained in step (b.3); (b.5) drying and / or calcining the mixture obtained in step (b.3), and optionally the mixture obtained in step (b.4), to obtain a powder; (b.6) preparing a mixture comprising water and the powder obtained in step (b.5); (b.7) milling the particles of the mixture obtained in step (b.6) until the particles of the mixture have a Dv90 in the range of 3 to 30 micrometers. or Step (b) comprises the steps of: (b.1') impregnating the source of platinum into the porous non-zeolitic oxide support using a solvent; (b.2') impregnating the impregnated porous non-zeolitic oxide support obtained in step (b.1') with a solution containing a source of said first oxide material comprising titania to obtain a mixture; (b.3') impregnating a source of one or more platinum group metals other than platinum onto the impregnated porous non-zeolitic oxide support obtained in step (b.2'); (b.4') drying and / or calcining the mixture obtained in step (b.3') to obtain a powder; (b.5') preparing a mixture comprising water and the powder obtained in step (b.4'); (b.6') milling the particles of the mixture obtained in step (b.5') until the particles of the mixture have a Dv90 in the range of 3 to 30 micrometers.

13. The method of claim 11 or 12, further comprising:

14. The porous non-zeolitic oxide support provided in step (b) has a water content of 0.6 ml / cm ３ ~2ml / cm ３ 14. The method of claim 11, wherein the pore volume is in the range of

15. 2. A process for oxidizing ammonia contained in an exhaust gas stream comprising the steps of: (1) providing said exhaust gas stream from a diesel engine; (2) passing the exhaust gas stream provided in step (1) through a catalyst according to any one of claims 1 to 10. A method comprising:

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