High ammonia storage capacity SCR catalyst

Abstract

The present invention relates to a catalyst for the selective catalytic reduction of nitrogen oxides, the catalyst having a first coating comprising a 12-ring pore zeolite material containing a first metal, the first metal being one or more of copper and iron, and a second coating comprising an 8-ring pore zeolite material containing a second metal, the second metal being one or more of copper and iron.

Description

[Technical Field]

[0001] The present invention relates to a catalyst for the selective catalytic reduction of nitrogen oxides, a method for producing a catalyst for the selective catalytic reduction of nitrogen oxides, the use of a catalyst for the selective catalytic reduction of nitrogen oxides and an exhaust gas treatment system comprising said catalyst. [Background technology]

[0002] US9352307B2 discloses a selective catalytic reduction (SCR) catalyst comprising a mixture of zeolitic materials, namely Cu-CHA and Fe-MFI.

[0003] Furthermore, EP2520365A2 also discloses a catalyst for use in selective catalytic reduction, which comprises a first molecular sieve having a large-pore, medium-pore, or meso-pore crystalline structure and optionally containing a first metal, and a second molecular sieve having a small-pore crystalline structure and optionally containing a second metal.Finally, US9597636B2 discloses a system comprising a first upstream SCR zone having a first ammonia storage capacity (storage capacity) and a second downstream SCR zone having a second ammonia storage capacity, wherein the second ammonia storage capacity is greater than the first ammonia storage capacity.

[0004] During transient cycles, such as during acceleration, fresh urea dosing can be limited. This has led to a need for improved selective catalytic reduction (SCR) catalysts that can optimize NOx conversion and minimize nitrous oxide (N2O) production while limiting urea dosing. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] US9352307B2 [Patent Document 2] EP2520365A2 [Patent Document 3] US9597636B2 Summary of the Invention [Effects of the Invention]

[0006] Surprisingly, it has been found that the selective catalytic reduction catalyst of the present invention can optimize NOx conversion and minimize nitrous oxide (N2O) production while limiting the dosage of urea. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 shows the NOx conversion performance of the catalyst of Example 1a) after aging. [Figure 2] FIG. 1 shows the N2O production obtained when using the catalyst of Example 1a) after aging. [Figure 3] FIG. 10 is a graph showing NOx emissions (ramp 180 to 450° C.) of the catalysts of Example 4 and Comparative Example 1 as a function of time. [Figure 4] FIG. 10 is a graph showing NOx emissions (ramp 250 to 450° C.) of the catalysts of Example 4 and Comparative Example 1 as a function of time. [Figure 5] FIG. 10 is a graph showing NOx emissions (ramp 180 to 450° C.) of the catalysts of Example 6 and Comparative Example 2 as a function of time. DETAILED DESCRIPTION OF THE INVENTION

[0008] I. Catalysts for Selective Catalytic Reduction of NOx Accordingly, the present invention provides a catalyst for selective catalytic reduction of nitrogen oxides, the catalyst comprising: (i) a substrate having 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 interior wall of the flow-through substrate extending therethrough; (ii) a first coating comprising a 12-ring pore zeolite material comprising a first metal, the first metal being one or more of copper and iron, the 12-ring pore zeolite material comprising the first metal in an amount of z1% by weight, calculated by dividing the mass of the first metal, calculated as CuO and Fe2O3, by the mass of the 12-ring pore zeolite material comprising the first metal; (iii) a second coating comprising an eight-ring pore zeolite material containing a second metal, the second metal being one or more of copper and iron, wherein the eight-ring pore zeolite material contains the second metal in an amount of z2% by weight, calculated by dividing the mass of the second metal, calculated as CuO and Fe2O3, by the mass of the eight-ring pore zeolite material containing the second metal. Equipped with wherein the first coating is disposed on a surface of an inner wall of the substrate, the surface defining an interface between the inner wall and the passageway, and extends over x% of the axial length of the substrate from the inlet end toward the outlet end of the substrate, where x is in the range of 10 to 75; the second coating extends over y% of the axial length of the substrate from the outlet end toward the inlet end, where y is in the range of 25 to 90; The ratio z1:z2 is in the range of 0.5:1 to 0.95:1 Regarding catalysts.

[0009] It is preferable that x is in the range of 20 to 72, more preferably in the range of 22 to 70, and further preferably in the range of 25 to 68. Alternatively, it is preferable that x is in the range of 10 to 18, and more preferably in the range of 10 to 15.

[0010] It is preferable that y is in the range of 27 to 80, more preferably in the range of 30 to 78, and further preferably in the range of 32 to 75.

[0011] Preferably, y is 100-x.

[0012] The second coating is preferably disposed on the surface of the inner wall of the substrate.

[0013] When x < y, it is preferred that x is in the range of 10 to 45, more preferably in the range of 20 to 40, and even more preferably in the range of 25 to 35. Alternatively, when x > y, it is preferred that x is in the range of 55 to 75, more preferably in the range of 60 to 72, even more preferably in the range of 62 to 70, and still more preferably in the range of 63 to 68. It is preferred that there is no overlap (duplication) between the first coating and the second coating.

[0014] Regarding the first coating, the 12-ring pore zeolite material contained in the first coating is a framework type selected from the group consisting of BEA, FAU, USY, GME, MOR, OFF, mixtures of two or more thereof, and mixed types of two or more thereof. More preferably, it has a framework type selected from the group consisting of BEA, FAU, mixtures of two or more thereof, and mixed types of two or more thereof. It is more preferred that the 12-ring pore zeolite material contained in the first coating has a framework type of BEA.

[0015] Therefore, the present invention is preferably a catalyst for selective catalytic reduction of nitrogen oxides, and the catalyst (i) a substrate comprising 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 the inner wall of the through-flow substrate extending therethrough; (ii) a first coating containing a 12-ring pore zeolite material containing one or more of copper and iron, and the 12-ring pore zeolite material contains the first metal in an amount of z1 mass% calculated by dividing the mass of the first metal calculated as CuO and Fe2O3 by the mass of the 12-ring pore zeolite material containing the first metal. Here, the 12-ring pore zeolite material contained in the first coating has a framework type of BEA. (iii) a second coating comprising an eight-ring pore zeolite material containing a second metal, the second metal being one or more of copper and iron, wherein the eight-ring pore zeolite material contains the second metal in an amount of z2% by weight, calculated by dividing the mass of the second metal, calculated as CuO and Fe2O3, by the mass of the eight-ring pore zeolite material containing the second metal. Equipped with wherein the first coating is disposed on a surface of an inner wall of the substrate, the surface defining an interface between the inner wall and the passageway, and extends over x% of the axial length of the substrate from the inlet end toward the outlet end of the substrate, where x is in the range of 10 to 75; the second coating extends over y% of the axial length of the substrate from the outlet end toward the inlet end, where y is in the range of 25 to 90; The ratio z1:z2 is in the range of 0.5:1 to 0.95:1; Regarding catalysts.

[0016] In the present invention, the 12-membered ring pore zeolite material contained in the first coating preferably contains a first metal that is iron. More preferably, the 12-membered ring pore zeolite material contains z1 mass% iron, calculated by dividing the mass of the first metal, calculated as Fe2O3, by the mass of the 12-membered ring pore zeolite material containing the first metal, where z1 is more preferably in the range of 1.0 to 10, more preferably 1.5 to 8, more preferably 2 to 6, more preferably 3 to 5, or more preferably 3.5 to 4.8.

[0017] Preferably, 0 to 0.001 mass%, more preferably 0 to 0.0001 mass%, and even more preferably 0 to 0.00001 mass% of the first metal is copper calculated as CuO. More preferably, the 12-membered ring pore zeolite material contained in the first coating does not contain copper.

[0018] Therefore, the present invention preferably relates to a catalyst for selective catalytic reduction of nitrogen oxides, the catalyst comprising: (i) a substrate having 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 interior wall of the flow-through substrate extending therethrough; (ii) a first coating comprising a 12-ring pore zeolite material comprising a first metal, the first metal being iron, in an amount of z1% by weight, calculated by dividing the mass of the first metal, calculated as Fe2O3, by the mass of the 12-ring pore zeolite material comprising the first metal, wherein the 12-ring pore zeolite material in the first coating has a framework type BEA; (iii) a second coating comprising an eight-ring pore zeolite material containing a second metal, the second metal being one or more of copper and iron, wherein the eight-ring pore zeolite material contains the second metal in an amount of z2% by weight, calculated by dividing the mass of the second metal, calculated as CuO and Fe2O3, by the mass of the eight-ring pore zeolite material containing the second metal. Equipped with wherein the first coating is disposed on a surface of an inner wall of the substrate, the surface defining an interface between the inner wall and the passageway, and extends over x% of the axial length of the substrate from the inlet end toward the outlet end of the substrate, where x is in the range of 10 to 75; the second coating extends over y% of the axial length of the substrate from the outlet end toward the inlet end, where y is in the range of 25 to 90; The ratio z1:z2 is in the range of 0.5:1 to 0.95:1; Regarding catalysts.

[0019] In the context of the present invention, it is preferred that 95 to 100 mass%, more preferably 98 to 100 mass%, and even more preferably 99 to 100 mass% of the framework structure of the 12-membered ring pore zeolite material be composed of Si, Al, O, and optionally H. The molar ratio of Si to Al in the framework structure of the 12-membered ring pore zeolite material, calculated as molar SiO2:Al2O3, is preferably in the range of 2:1 to 37:1, more preferably 3:1 to 35:1, even more preferably 4:1 to 20:1, and even more preferably 5:1 to 15:1. It is even more preferred that the molar ratio of Si to Al be in the range of 6:1 to 12:1.

[0020] In the context of the present invention, the 12-ring pore zeolitic material, more preferably the zeolitic material having the framework type BEA, is preferably prepared by a template-free process.

[0021] The first coating preferably contains the 12-membered ring pore zeolite material containing the first metal in an amount in the range of 70 to 98 mass %, more preferably 75 to 97 mass %, even more preferably 80 to 95 mass %, and more preferably 85 to 92 mass %, based on the mass of the first coating.

[0022] Preferably, the first coating further comprises a 10-ring pore zeolite material containing a third metal, which is one or more of copper and iron, and preferably the third metal is iron.

[0023] The 10-ring pore zeolite material contained in the first coating preferably has a framework type selected from the group consisting of MFI, MWW, AEL, HEU, FER, AFO, a mixture of two or more thereof, and a mixed type of two or more thereof. More preferably, the 10-ring pore zeolite material contained in the first coating has a framework type MFI.

[0024] The 10-membered ring pore zeolite material contained in the first coating preferably contains a third metal, which is iron. The 10-membered ring pore zeolite material preferably contains iron in an amount ranging from 0.5 to 9 mass%, more preferably from 1 to 7 mass%, even more preferably from 1.5 to 6 mass%, even more preferably from 2 to 5 mass%, and still more preferably from 2.5 to 4.5 mass% (calculated by dividing the mass of the third metal, calculated as Fe2O3, by the mass of the 10-membered ring pore zeolite material containing the third metal).

[0025] Preferably, 0 to 0.001 mass %, more preferably 0 to 0.0001 mass %, and even more preferably 0 to 0.00001 mass % of the third metal is copper calculated as CuO. More preferably, the 10-membered ring pore zeolite material contained in the first coating does not contain copper.

[0026] It is preferable that 95 to 100 mass %, more preferably 98 to 100 mass %, and even more preferably 99 to 100 mass % of the framework structure of the 10-membered ring pore zeolite material is composed of Si, Al, O, and optionally H.

[0027] The molar ratio of Si to Al, calculated as molar SiO2:Al2O3, in the framework structure of the 10-membered ring pore zeolite material is preferably in the range of 2:1 to 60:1, more preferably in the range of 5:1 to 50:1, even more preferably in the range of 10:1 to 40:1, even more preferably in the range of 15:1 to 35:1, even more preferably in the range of 20:1 to 30:1, and even more preferably in the range of 23:1 to 29:1.

[0028] The first coating suitably contains the 10-membered ring pore zeolite material containing a third metal in an amount in the range of 1 to 8 mass %, preferably in the range of 2 to 7 mass %, more preferably in the range of 3 to 6 mass %, based on the mass of the first coating.

[0029] The first coating further comprises an oxide binder, and the oxide binder more preferably comprises one or more of zirconia, alumina, titania, silica, and mixed oxides containing two or more of Zr, Al, Ti, and Si, more preferably comprises one or more of silica, alumina, and zirconia, more preferably comprises one or more of silica and zirconia, and more preferably comprises silica.

[0030] Suitably, the first coating comprises an oxide binder in an amount in the range of 0.5 to 8% by weight, more preferably in the range of 2 to 7% by weight, even more preferably in the range of 3 to 6% by weight (these values being based on the weight of the first coating).

[0031] Therefore, the present invention preferably relates to a catalyst for selective catalytic reduction of nitrogen oxides, the catalyst comprising: (i) a substrate having 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 interior wall of the flow-through substrate extending therethrough; (ii) a first coating comprising a 12-ring pore zeolite material comprising a first metal, the first metal being iron, in an amount of z1% by weight, calculated by dividing the mass of the first metal, calculated as Fe2O3, by the mass of the 12-ring pore zeolite material comprising the first metal, wherein the 12-ring pore zeolite material in the first coating has a framework type BEA; wherein the first coating further comprises a 10-ring pore zeolite material, more preferably a zeolite material having framework type MFI, comprising a third metal, the third metal being one or more of copper and iron, more preferably iron; The first coating more preferably further comprises an oxide binder. (iii) a second coating comprising an eight-ring pore zeolite material containing a second metal, the second metal being one or more of copper and iron, wherein the eight-ring pore zeolite material contains the second metal in an amount of z2% by weight, calculated by dividing the mass of the second metal, calculated as CuO and Fe2O3, by the mass of the eight-ring pore zeolite material containing the second metal. Equipped with wherein the first coating is disposed on a surface of an inner wall of the substrate, the surface defining an interface between the inner wall and the passageway, and extends over x% of the axial length of the substrate from the inlet end toward the outlet end of the substrate, where x is in the range of 10 to 75; the second coating extends over y% of the axial length of the substrate from the outlet end toward the inlet end, where y is in the range of 25 to 90; The ratio z1:z2 is in the range of 0.5:1 to 0.95:1; Regarding catalysts.

[0032] In the context of the present invention, it is suitable that 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 the first coating consists of a 12-membered ring pore zeolite material containing a first metal which is one or more of copper and iron, and preferably one or more of a 10-membered ring pore zeolite material containing a third metal as defined above and the oxide binder as defined above, more preferably a 10-membered ring pore zeolite material containing a third metal as defined above and the oxide binder as defined above.

[0033] The first coating is 1.5 to 5 g / in 3 in the range of 2 to 4 g / in 3 in the range of 2.5 to 3.5 g / in 3 It is preferred that the catalyst be present at a loading in the range of 0.1 to 1.0.

[0034] It is preferable that a maximum of 10 ppm, more preferably 0 to 5 ppm, even more preferably 0 to 2 ppm, more preferably 0 to 1 ppm, and more preferably 0 to 0.5 ppm of the first coating is made of platinum, preferably platinum, palladium, and rhodium, and more preferably platinum group metals. That is, it is preferable that the first coating is substantially free of platinum, more preferably platinum, palladium, and rhodium, and more preferably platinum group metals, and more preferably is free of platinum.

[0035] It is preferable that the first coating comprises 0 to 0.01 mass%, more preferably 0 to 0.001 mass%, and even more preferably 0 to 0.0001 mass% of the 8-membered ring pore zeolite material. In other words, it is preferable that the first coating does not substantially contain, more preferably does not contain, the 8-membered ring pore zeolite material.

[0036] The first coating preferably comprises 0 to 0.001 mass%, more preferably 0 to 0.0001 mass%, and even more preferably 0 to 0.00001 mass% of copper calculated as CuO. In other words, the first coating is preferably substantially free of copper, more preferably free of copper.

[0037] The first coating (ii) has an ammonia storage capacity A1 of at least 2.1 mmol / g, preferably in the range of 2.2 to 10.0 mmol / g, more preferably in the range of 2.5 to 5.0 mmol / g. (NH3) The ammonia storage capacity is determined as defined in Reference Example 1.

[0038] With respect to the second coating, it is preferred that the 8-ring pore zeolite material contained in the second coating 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 and AEI, and more preferably having framework type CHA.

[0039] The 8-membered ring pore zeolite material contained in the second coating preferably contains copper as a second metal. The 8-membered ring pore zeolite material contains z2% by mass of copper, calculated by dividing the mass of the second metal, calculated as CuO, by the mass of the 8-membered ring pore zeolite material containing the second metal, where z2 is preferably in the range of 2.0 to 15, more preferably 3 to 10, more preferably 4 to 8, more preferably 4.5 to 7, or even more preferably 4.9 to 6.

[0040] It is preferable that the first metal contains 0 to 0.001 mass%, more preferably 0 to 0.0001 mass%, and even more preferably 0 to 0.00001 mass% of iron calculated as Fe2O3. It is preferable that the 8-membered ring pore zeolite material contained in the second coating does not contain iron.

[0041] Preferably, 95 to 100 mass %, more preferably 98 to 100 mass %, and even more preferably 99 to 100 mass % of the framework structure of the 8-membered ring pore zeolite material is composed of Si, Al, O, and optionally H. In the framework structure, the molar ratio of Si to Al (calculated as molar SiO2:Al2O3) is suitably in the range of 2:1 to 50:1, more preferably 2:1 to 45:1, more preferably 10:1 to 35:1, more preferably 15:1 to 25:1, and more preferably 16:1 to 22:1.

[0042] It is preferable that the second coating contains the 8-membered ring pore zeolite material containing the second metal in an amount in the range of 85 to 99 mass %, more preferably in the range of 90 to 98 mass %, and more preferably in the range of 92 to 97 mass %, based on the mass of the second coating.

[0043] The second coating preferably further comprises an oxide binder, more preferably comprising one or more of zirconia, alumina, titania, silica, and mixed oxides comprising two or more of Zr, Al, Ti, and Si, more preferably comprising one or more of silica, alumina, and zirconia, more preferably comprising one or more of alumina and zirconia, more preferably comprising zirconia.

[0044] The second coating preferably contains an oxide binder in an amount in the range of 0.5 to 8 mass %, more preferably in the range of 2 to 7 mass %, and even more preferably in the range of 3 to 6 mass %, based on the mass of the first coating.

[0045] Therefore, the present invention preferably relates to a catalyst for selective catalytic reduction of nitrogen oxides, the catalyst comprising: (i) a substrate having 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 interior wall of the flow-through substrate extending therethrough; (ii) a first coating comprising a 12-ring pore zeolite material comprising a first metal, the first metal being iron, in an amount of z1% by weight, calculated by dividing the mass of the first metal, calculated as FeO, by the mass of the 12-ring pore zeolite material comprising the first metal; (iii) a second coating comprising an 8-ring pore zeolite material comprising a second metal, the second metal being one or more of copper and iron, the 8-ring pore zeolite material comprising the second metal in an amount of z2% by weight, calculated by dividing the mass of the second metal, calculated as CuO and Fe2O3, by the mass of the 8-ring pore zeolite material comprising the second metal; wherein the 8-ring pore zeolite material has a framework type CHA, the second coating further comprises an oxide binder; Equipped with wherein the first coating is disposed on a surface of an inner wall of the substrate, the surface defining an interface between the inner wall and the passageway, and extends over x% of the axial length of the substrate from the inlet end toward the outlet end of the substrate, where x is in the range of 10 to 75; the second coating extends over y% of the axial length of the substrate from the outlet end toward the inlet end, where y is in the range of 25 to 90; The ratio z1:z2 is in the range of 0.5:1 to 0.95:1; Regarding catalysts.

[0046] More preferably, the present invention relates to a catalyst for selective catalytic reduction of nitrogen oxides, the catalyst comprising: (i) a substrate having 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 interior wall of the flow-through substrate extending therethrough; (ii) a first coating comprising a 12-ring pore zeolite material comprising a first metal, the first metal being iron, in an amount of z1% by weight, calculated by dividing the mass of the first metal, calculated as Fe2O3, by the mass of the 12-ring pore zeolite material comprising the first metal, wherein the 12-ring pore zeolite material in the first coating has a framework type BEA; wherein the first coating further comprises a 10-ring pore zeolite material, more preferably a zeolite material having framework type MFI, comprising a third metal, the third metal being one or more of copper and iron, more preferably iron; The first coating more preferably further comprises an oxide binder. (iii) a second coating comprising an 8-ring pore zeolite material comprising a second metal, the second metal being one or more of copper and iron, the 8-ring pore zeolite material comprising the second metal in an amount of z2% by weight, calculated by dividing the mass of the second metal, calculated as CuO and Fe2O3, by the mass of the 8-ring pore zeolite material comprising the second metal; wherein the 8-ring pore zeolite material has a framework type CHA, the second coating further comprises an oxide binder; Equipped with wherein the first coating is disposed on a surface of an inner wall of the substrate, the surface defining an interface between the inner wall and the passageway, and extends over x% of the axial length of the substrate from the inlet end toward the outlet end of the substrate, where x is in the range of 10 to 75; the second coating extends over y% of the axial length of the substrate from the outlet end toward the inlet end, where y is in the range of 25 to 90; The ratio z1:z2 is in the range of 0.5:1 to 0.95:1; Regarding catalysts.

[0047] In the context of the present invention, it is preferable that 95 to 100 mass %, more preferably 98 to 100 mass %, even more preferably 99 to 100 mass %, and more preferably 99.5 to 100 mass % of the second coating is made of an 8-membered ring pore zeolite material containing a second metal which is at least one of copper and iron, more preferably copper, and more preferably the oxide binder defined above.

[0048] The second coating is 1.5 to 5 g / in 3 in the range of 1.75 to 4 g / in 3 in the range of 2 to 3.5 g / in 3 It is preferred that the catalyst be present at a loading in the range of 1000 to 15000.

[0049] It is preferred that a maximum of 10 ppm, more preferably 0 to 5 ppm, even more preferably 0 to 2 ppm, more preferably 0 to 1 ppm, and more preferably 0 to 0.5 ppm of the second coating is made of platinum, more preferably platinum, palladium, and rhodium, and more preferably platinum group metals. In other words, it is preferred that the second coating is substantially free of platinum, more preferably platinum, palladium, and rhodium, and more preferably platinum group metals, and more preferably is free of platinum.

[0050] It is preferable that the second coating comprises 0 to 0.01 mass%, more preferably 0 to 0.001 mass%, and even more preferably 0 to 0.0001 mass% of the 12-membered ring pore zeolite material. In other words, it is preferable that the second coating does not substantially contain, and more preferably does not contain, the 12-membered ring pore zeolite material.

[0051] Preferably, the second coating comprises 0 to 0.01 mass%, more preferably 0 to 0.001 mass%, and even more preferably 0 to 0.0001 mass% of the 10-membered ring pore zeolite material. In other words, the second coating is substantially free of, and more preferably free of, the 10-membered ring pore zeolite material.

[0052] It is preferable that the second coating contains 0 to 0.001 mass%, more preferably 0 to 0.0001 mass%, and even more preferably 0 to 0.00001 mass% of iron calculated as Fe2O3. In other words, it is preferable that the second coating contains substantially no iron, and more preferably contains no iron.

[0053] The second coating (iii) has an ammonia storage capacity A2 of less than 2 mmol / g, preferably in the range of 0.5 to 1.99 mmol / g, more preferably in the range of 1 to 1.95 mmol / g. (NH3) The ammonia storage capacity is determined as defined in Reference Example 1.

[0054] The substrate is preferably a flow-through substrate or a wall-flow filter substrate, more preferably a flow-through substrate.

[0055] It is preferred that the flow-through substrate comprises, more preferably consists of, a ceramic material, more preferably comprising one or more of alumina, silica, silicates, aluminosilicates, more preferably cordierite or mullite, aluminotitanate, silicon carbide, zirconia, magnesia, more preferably spinel, and titania, more preferably one or more of silicon carbide and cordierite, more preferably cordierite, more preferably consisting of (the like).

[0056] It is preferable that the substrate has a substrate length in the range of 1 to 15 inches, more preferably in the range of 2 to 10 inches.

[0057] The substrate preferably has a substrate width in the range of 0.5 to 3 inches, more preferably in the range of 0.75 to 2 inches.

[0058] Suitably, the catalyst comprises, more preferably consists of, one substrate (i), a first coating (ii) and a second coating (iii).

[0059] Preferably, the substrate comprises a first upstream substrate and a second downstream substrate, the first coating (ii) being disposed on the first upstream substrate, and the second coating (ii) being disposed on the second downstream substrate. More preferably, there is a gap of less than 0.2 inches between the juxtaposed first upstream substrate and second downstream substrate, and more preferably, there is no gap.

[0060] Preferably, the first upstream substrate is a flow-through substrate, more preferably a cordierite flow-through substrate, and preferably, the second downstream substrate is a flow-through substrate, more preferably a cordierite flow-through substrate.

[0061] It is preferred that the first upstream substrate and the second downstream substrate are the same in chemical composition and physical properties, and it may also be preferred that they be the same dimensions (diameter and / or length).

[0062] In addition, in the context of the present invention, it is also conceivable that the first coating (ii) and the second coating (iii) are disposed not only on the first upstream substrate and the second downstream substrate as described above, but also on, for example, a first upstream substrate, a second downstream substrate, and a third intermediate substrate disposed / located between the first upstream substrate and the second downstream substrate.

[0063] It is preferred that the first upstream substrate, the third intermediate substrate, and the second downstream substrate be identical in chemical composition and physical properties, and it may also be preferred that they be identical in size (diameter and / or length).

[0064] The first coating (ii) has an ammonia storage capacity A1 (NH3) and the second coating (iii) has an ammonia storage capacity A2 (NH3) A1 (NH3) A2 (NH3) Preferably, the ammonia storage capacity is greater than 1000 kJ / cm, and the ammonia storage capacity is determined as defined in Reference Example 1.

[0065] A1 (NH3) :A2 (NH3) The ratio is preferably in the range of 1.25:1 to 3:1, more preferably in the range of 1.3:1 to 2:1, and even more preferably in the range of 1.35:1 to 1.9:1.

[0066] The present invention further provides a method for producing the catalyst for selective catalytic reduction of nitrogen oxides according to the present invention, the method comprising the steps of: (1) providing a substrate having 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 interior wall of the flow-through substrate extending therethrough; (2) preparing a first mixture comprising water and a 12-ring pore zeolite material comprising a first metal, the first metal being one or more of copper and iron, wherein the 12-ring pore zeolite material comprises the first metal in an amount of z1% by weight, calculated by dividing the mass of the first metal, calculated as CuO and Fe2O3, by the mass of the 12-ring pore zeolite material comprising the first metal; (3) disposing the first mixture obtained in (2) on the inner wall surface of the substrate prepared in (1) over x% of the axial length of the substrate from the inlet end to the outlet end of the substrate, where x is in the range of 10 to 75; (4) drying the mixture-treated substrate from (3) to obtain a substrate having a first coating disposed thereon; and optionally, baking; (5) preparing a second mixture comprising water and an 8-ring pore zeolite material containing a second metal, the second metal being one or more of copper and iron, wherein the 8-ring pore zeolite material contains z2% by weight of the second metal, calculated as the mass of the second metal, calculated as CuO and Fe2O3, divided by the mass of the 8-ring pore zeolite material containing the second metal; (6) disposing the second mixture obtained in (5) on the substrate having the first coating disposed thereon from the outlet end of the substrate toward the inlet end thereof over y% of the axial length of the substrate, where y is in the range of 25 to 90; (7) drying the mixture-treated substrate obtained in (6) to obtain a substrate having the first coating and the second coating disposed thereon; (8) The substrate obtained in (7) on which the first coating and the second coating are disposed is calcined to obtain a catalyst. Including, Here, the ratio z1:z2 is in the range of 0.5:1 to 0.95:1. Regarding the method.

[0067] Regarding (2), the following structure is further provided: (2.1) preparing a 12-ring pore zeolite material, more preferably a 12-ring pore zeolite material as defined above; (2.2) mixing a source of a first metal, preferably an iron salt, with the 12-ring pore zeolite material obtained in (2.1); (2.3) Calcining the mixture obtained in (2.2) to obtain a 12-ring pore zeolite material containing a first metal, preferably iron; (2.4) Combining water with a 12-ring pore zeolite material containing a first metal, preferably iron, and preferably an organic acid, more preferably tartaric acid. It is preferred that the composition contains:

[0068] Regarding (2), the following structure is further provided: (2.5) adding a third metal-containing 10-ring pore zeolite material, more preferably a 10-ring pore zeolite material as defined above, to the mixture obtained in (2.4); (2.6) More preferably, adding a source of oxide binder, more preferably colloidal silica, to the mixture obtained in (2.5); (2.7) More preferably, an additive is added to the mixture obtained in (2.6). It is preferred that the composition contains:

[0069] The drying described in (4) is preferably carried out in a gas atmosphere having a temperature in the range of 100 to 160°C, more preferably in the range of 120 to 140°C, and the gas atmosphere preferably contains oxygen, more preferably is air.

[0070] The drying described in (4) is preferably carried out for a duration in the range of 5 minutes to 2 hours, more preferably 10 minutes to 1 hour.

[0071] After drying, the firing described in (4) is preferably carried out in a gas atmosphere having a temperature in the range of 450 to 700°C, more preferably in the range of 500 to 600°C, and the gas atmosphere preferably contains oxygen, more preferably is air.

[0072] After drying, the firing described in (4) is preferably carried out for a period of time ranging from 5 minutes to 2 hours, more preferably for a period of time ranging from 10 minutes to 1 hour.

[0073] (5) is (5.1) preparing an 8-ring pore zeolitic material containing a second metal which is one or more of copper and iron, more preferably copper, more preferably preparing an 8-ring pore zeolitic material as defined above; (5.2) combining water with the 8-ring pore zeolite material obtained in (5.1) containing a second metal, which is one or more of copper and iron, more preferably copper; (5.3) Adding a source of oxide binder, preferably zirconium acetate, to the mixture obtained in (5.2). It is preferred that the composition contains:

[0074] The drying described in (7) is preferably carried out in a gas atmosphere having a temperature in the range of 100 to 160°C, more preferably in the range of 120 to 140°C, and the gas atmosphere preferably contains oxygen, more preferably is air.

[0075] The drying described in (7) is preferably carried out for a duration in the range of 5 minutes to 2 hours, more preferably in the range of 10 minutes to 1 hour.

[0076] After drying, the firing described in (7) is preferably carried out in a gas atmosphere having a temperature in the range of 400 to 600°C, more preferably 450 to 550°C, and the gas atmosphere preferably contains oxygen, and more preferably the gas atmosphere is air.

[0077] After drying, the firing by (7) is preferably carried out for a time in the range of 5 minutes to 2 hours, more preferably for a duration in the range of 10 minutes to 1 hour.

[0078] x is preferably in the range of 20 to 72, more preferably in the range of 22 to 70, and still more preferably in the range of 25 to 68.

[0079] y is preferably in the range of 27 to 80, more preferably in the range of 30 to 78, and still more preferably in the range of 32 to 75.

[0080] It is preferable that y is 100 - x.

[0081] The second coating is preferably disposed on the surface of the inner wall of the substrate.

[0082] When x < y, it is preferable that x is in the range of 10 to 45, more preferably in the range of 20 to 40, and still more preferably in the range of 25 to 35. Alternatively, when x > y, it is preferable that x is in the range of 55 to 75, more preferably in the range of 60 to 72, still more preferably in the range of 62 to 70, and more preferably in the range of 63 to 68.

[0083] It is preferable that there is no overlap between the first coating and the second coating.

[0084] The method of the present invention preferably consists of (1), (2), (3), (4), (5), (6) and (7).

[0085] The present invention further relates to a catalyst for selective catalytic reduction of nitrogen oxides, more preferably a catalyst for selective catalytic reduction of nitrogen oxides according to the present invention and as defined above, and a catalyst for selective catalytic reduction of nitrogen oxides obtainable or obtained by the method according to the present invention and as defined above.

[0086] The present invention further relates to an exhaust gas treatment system for treating exhaust gases emitted by a combustion engine, preferably a diesel engine, comprising one or more catalysts for the selective catalytic reduction of nitrogen oxides according to the present invention and one or more of a diesel oxidation catalyst, a catalyzed soot filter and an ammonia oxidation catalyst.

[0087] According to a first aspect of the present invention, the system preferably comprises a diesel oxidation catalyst, a catalyzed soot filter, and one or more catalysts for selective catalytic reduction of nitrogen oxides according to the present invention.

[0088] According to the first aspect, it is preferred that the diesel oxidation catalyst is arranged upstream of a catalyzed soot filter, which in turn is arranged upstream of one or more catalysts for the selective catalytic reduction of nitrogen oxides according to the invention.

[0089] Also, according to the first aspect, it is preferred to arrange a catalyzed soot filter upstream of two catalysts for the selective catalytic reduction of nitrogen oxides according to the present invention, in which case the two catalysts for the selective catalytic reduction of nitrogen oxides are arranged in parallel to each other.

[0090] According to the first aspect, it is more preferred that the system further comprises two ammonia oxidation catalysts, each of which is arranged downstream of one of the catalysts for selective catalytic reduction of nitrogen oxides according to the present invention, so that the two ammonia oxidation catalysts are also preferably arranged in parallel to each other.

[0091] According to a second aspect of the present invention, it is a preferred embodiment that the system includes the catalyst for selective catalytic reduction of nitrogen oxides according to the present invention and a catalyzed soot filter.

[0092] According to the second aspect, it is preferable to dispose a catalyzed soot filter downstream of the catalyst for selective catalytic reduction of nitrogen oxides according to the present invention.

[0093] According to the second aspect, the system further comprises a diesel oxidation catalyst, which is preferably arranged downstream of the catalyst for selective catalytic reduction of nitrogen oxides according to the invention and upstream of the catalyzed soot filter.

[0094] Furthermore, according to the second aspect, the system further comprises an ammonia oxidation catalyst, and it is preferable that the ammonia oxidation catalyst is disposed downstream of the catalyzed particulate filter.

[0095] The present invention further relates to the use of the catalyst according to the invention for the selective catalytic reduction of nitrogen oxides contained in an exhaust gas stream, preferably an exhaust gas stream from a diesel engine.

[0096] The present invention further relates to the use of an exhaust gas treatment system according to the present invention for treating an exhaust gas stream leaving a diesel engine.

[0097] The present invention further provides a method for selective catalytic reduction of NOx, wherein the NOx is contained in an exhaust gas stream, the method comprising: (1) providing an exhaust gas stream, preferably an exhaust gas stream from a diesel engine; (2) passing the exhaust gas stream provided in (1) through the catalyst of the present invention; The present invention relates to a method comprising:

[0098] The present invention further provides a method for treating an exhaust gas stream from a diesel engine, comprising the steps of: (1') providing said exhaust gas stream; (2') passing the exhaust gas stream provided in (1') through an exhaust gas treatment system according to the present invention; The present invention relates to a method comprising:

[0099] II. Further catalysts for selective catalytic reduction of NOx Accordingly, the present invention provides a catalyst for selective catalytic reduction of nitrogen oxides, comprising: a substrate having 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 interior wall of the flow-through substrate extending therethrough; a coating disposed on a surface of an interior wall of the substrate, the surface defining an interface between the interior wall and the passageway, the coating comprising a 12-ring pore zeolite material comprising a first metal, the first metal being one or more of copper and iron, wherein the 12-ring pore zeolite material comprises the first metal in an amount of z% by weight, calculated as the mass of the first metal, calculated as CuO and Fe2O3, divided by the mass of the 12-ring pore zeolite material comprising the first metal. Equipped with wherein the coating further comprises a 10-ring pore zeolite material comprising a second metal, the second metal being one or more of copper and iron, the 10-ring pore zeolite material comprising the second metal in an amount of y% by weight, calculated by dividing the mass of the second metal, calculated as CuO and Fe2O3, by the mass of the 10-ring pore zeolite material comprising the second metal; where y is in the range of 0.5 to 9, and y <zである Regarding catalysts.

[0100] The coating preferably extends over or covers 90 to 100%, more preferably 95 to 100%, and even more preferably 98 to 100% of the axial length of the substrate.

[0101] The 12-ring pore zeolite material contained in the coating preferably has a framework type selected from the group consisting of BEA, FAU, USY, GME, MOR, OFF, a mixture of two or more thereof, and a mixed type of two or more thereof, more preferably a framework type selected from the group consisting of BEA, FAU, a mixture of two or more thereof, and a mixed type of two or more thereof, and even more preferably a framework type BEA.

[0102] The 12-membered ring pore zeolite material contained in the coating preferably contains a first metal that is iron. The 12-membered ring pore zeolite material contains z mass% iron, calculated by dividing the mass of the first metal, calculated as Fe2O3, by the mass of the 12-membered ring pore zeolite material containing the first metal, where z is in the range of 1.0 to 10, more preferably 1.5 to 8, more preferably 2 to 6, more preferably 3 to 5, or even more preferably 3.5 to 4.8.

[0103] It is preferable that 0 to 0.001 mass %, more preferably 0 to 0.0001 mass %, and even more preferably 0 to 0.00001 mass % of the first metal is copper calculated as CuO. It is preferable that the 12-membered ring pore zeolite material contained in the coating does not contain copper.

[0104] Preferably, 95 to 100 mass%, more preferably 98 to 100 mass%, and even more preferably 99 to 100 mass% of the framework structure of the 12-membered ring pore zeolite material is composed of Si, Al, O, and optionally H. In this case, the molar ratio of Si to Al (calculated as molar SiO2:Al2O3) in the framework structure is preferably in the range of 2:1 to 37:1, more preferably 3:1 to 35:1, more preferably 4:1 to 20:1, and more preferably 5:1 to 15:1. It is even more preferable that the molar ratio of Si to Al is in the range of 6:1 to 12:1.

[0105] In the context of the present invention, the 12-ring pore zeolitic material, more preferably the zeolitic material having the framework type BEA, is preferably prepared by a template-free process.

[0106] The coating preferably contains the 12-membered ring pore zeolite material containing the first metal in an amount ranging from 70 to 98 mass %, more preferably from 75 to 97 mass %, even more preferably from 80 to 95 mass %, and still more preferably from 85 to 92 mass %, based on the mass of the coating.

[0107] It is preferred that the 10-ring pore zeolite material includes a second metal which is iron.

[0108] The 10-membered ring pore zeolite material contained in the coating preferably has a framework type selected from the group consisting of MFI, MWW, AEL, HEU, FER, AFO, a mixture of two or more of these, and a mixed type of two or more of these. It is more preferable that the 10-membered ring pore zeolite material contained in the coating has a framework type MFI.

[0109] Accordingly, the present invention provides a catalyst for selective catalytic reduction of nitrogen oxides, comprising: a substrate having 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 interior wall of the flow-through substrate extending therethrough; a coating disposed on a surface of an interior wall of the substrate, the surface defining an interface between the interior wall and the passageway, the coating comprising a 12-ring pore zeolite material comprising a first metal, the first metal being iron, wherein the 12-ring pore zeolite material comprises the first metal in an amount of z% by weight, calculated as the mass of the first metal, calculated as FeO, divided by the mass of the 12-ring pore zeolite material comprising the first metal, the 12-ring pore zeolite material having a framework type BEA; Equipped with wherein the coating further comprises a 10-ring pore zeolite material comprising a second metal, the second metal being iron, and the 10-ring pore zeolite material comprises the second metal in an amount of y% by mass, calculated by dividing the mass of the second metal, calculated as Fe2O3, by the mass of the 10-ring pore zeolite material comprising the second metal, (the 10-ring pore zeolite material comprised in the coating has a framework type MFI); where y is in the range of 0.5 to 9, and y <zである、 It is preferred that it relates to a catalyst.

[0110] In the present invention, it is preferable that the 10-membered ring pore zeolite material contained in the coating contains a second metal, which is iron, and that the 10-membered ring pore zeolite material contains y mass% of iron, calculated by dividing the mass of the second metal, calculated as Fe2O3, by the mass of the 10-membered ring pore zeolite material containing the second metal, where y is preferably in the range of 1 to 7, more preferably in the range of 1.5 to 6, more preferably in the range of 2 to 5, and more preferably in the range of 2.5 to 4.5.

[0111] Preferably, 0 to 0.001 mass%, more preferably 0 to 0.0001 mass%, and even more preferably 0 to 0.00001 mass% of the second metal is copper calculated as CuO. Preferably, the 10-membered ring pore zeolite material contained in the coating does not contain copper.

[0112] Preferably, 95 to 100 mass%, more preferably 98 to 100 mass%, and even more preferably 99 to 100 mass% of the framework structure of the 10-membered ring pore zeolite material is composed of Si, Al, O, and optionally H. In this case, the molar ratio of Si to Al in the framework structure (calculated as molar SiO2:Al2O3) is more preferably in the range of 2:1 to 60:1, more preferably in the range of 5:1 to 50:1, more preferably in the range of 10:1 to 40:1, more preferably in the range of 15:1 to 35:1, more preferably in the range of 20:1 to 30:1, and more preferably in the range of 23:1 to 29:1.

[0113] The coating suitably contains the second metal-containing 10-ring pore zeolite material in an amount in the range of 1 to 8 mass %, preferably in the range of 2 to 7 mass %, more preferably in the range of 3 to 6 mass %, based on the mass of the coating.

[0114] The coating preferably further comprises an oxide binder, more preferably comprising one or more of zirconia, alumina, titania, silica, and mixed oxides comprising two or more of Zr, Al, Ti, and Si, more preferably comprising one or more of silica, alumina, and zirconia, more preferably comprising one or more of silica and zirconia, more preferably comprising silica.

[0115] The coating suitably contains an oxide binder in an amount in the range of 0.5 to 8 mass %, more preferably in the range of 2 to 7 mass %, and even more preferably in the range of 3 to 6 mass %, based on the mass of the coating.

[0116] Preferably, 95 to 100 mass%, more preferably 98 to 100 mass%, even more preferably 99 to 100 mass%, and more preferably 99.5 to 100 mass% of the coating comprises a 12-membered ring pore zeolite material containing a first metal which is one or more of copper and iron, more preferably iron, and a 10-membered ring pore zeolite material containing a second metal which is one or more of copper and iron, more preferably iron, and more preferably the oxide binder defined above.

[0117] The coating is 1.5 to 5 g / in 3 in the range of 2 to 4 g / in 3 in the range of 2.5 to 3.5 g / in 3 It is preferred that the catalyst be present at a loading in the range of 1000 to 15000.

[0118] It is preferred that a maximum of 10 ppm, more preferably 0 to 5 ppm, even more preferably 0 to 2 ppm, more preferably 0 to 1 ppm, and even more preferably 0 to 0.5 ppm of the coating is made of platinum, preferably platinum, palladium, and rhodium, and more preferably any of the platinum group metals. In other words, it is preferred that the coating is substantially free of platinum, palladium, and rhodium, more preferably platinum group metals, and more preferably is free of platinum.

[0119] The coating preferably comprises 0 to 0.01 mass%, more preferably 0 to 0.001 mass%, and even more preferably 0 to 0.0001 mass% of the 8-membered ring pore zeolite material. In other words, the coating is substantially free of, and more preferably free of, the 8-membered ring pore zeolite material.

[0120] The coating preferably comprises 0 to 0.001 mass%, more preferably 0 to 0.0001 mass%, and even more preferably 0 to 0.00001 mass% of copper calculated as CuO. In other words, the coating is preferably substantially free of copper, more preferably free of copper.

[0121] The coating has an ammonia storage capacity A1 of at least 2.1 mmol / g, preferably in the range of 2.2 to 10.0 mmol / g, and more preferably in the range of 2.5 to 5.0 mmol / g. (NH3) The ammonia storage capacity is determined as defined in Reference Example 1.

[0122] The catalyst of the present invention preferably comprises a substrate and a coating.

[0123] The present invention further provides a method for producing a catalyst according to the invention, comprising the steps of: (1') providing a substrate having 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 interior wall of the flow-through substrate extending therethrough; (2') preparing a mixture comprising water and a 12-ring pore zeolite material comprising a first metal, the first metal being one or more of copper and iron, wherein the 12-ring pore zeolite material comprises the first metal in an amount of z% by weight, calculated by dividing the mass of the first metal, calculated as CuO and Fe2O3, by the mass of the 12-ring pore zeolite material comprising the first metal; and further comprising a 10-ring pore zeolite material comprising a second metal, the second metal being one or more of copper and iron, wherein the 10-ring pore zeolite material comprises the second metal in an amount of y% by weight, calculated by dividing the mass of the second metal, calculated as CuO and Fe2O3, by the mass of the 10-ring pore zeolite material comprising the second metal; (3') disposing the mixture obtained in (2') on the inner wall surface of the substrate prepared in (1') over x% of the axial length of the substrate from the inlet end to the outlet end of the substrate, where x is in the range of 10 to 75; (4') drying the mixture-treated substrate obtained in (3') to obtain a substrate having a coating disposed thereon; (5') Calcining the substrate having the coating disposed thereon obtained in (4') to obtain a catalyst; where y is in the range of 0.5 to 9, and y <zである It is preferred that the present invention relates to a method.

[0124] (2') further includes (2'.1) preparing a 12-ring pore zeolite material, more preferably a 12-ring pore zeolite material as defined above; (2'.2) mixing a source of a first metal, preferably an iron salt, with the 12-ring pore zeolite material obtained in (2'.1); (2'.3) Calcining the mixture obtained in (2'.2) to obtain a 12-ring pore zeolite material containing a first metal, preferably iron; (2'.4) combining water with a 12-ring small pore zeolite material comprising a first metal, more preferably iron, and more preferably an organic acid, more preferably tartaric acid; (2'.5) adding a second metal-containing 10-ring pore zeolitic material, more preferably a 10-ring pore zeolitic material as defined above, to the mixture obtained in (2'.4); (2'.6) More preferably, adding to the mixture obtained in (2'.5) a source of an oxide binder, more preferably colloidal silica; (2'.7) More preferably, an additive is added to the mixture obtained in (2'.6). It is also preferable that (2') further comprises: (2'.1) preparing a 12-ring pore zeolite material, more preferably a 12-ring pore zeolite material as defined above; (2'.2) mixing a source of a first metal, preferably an iron salt, with the 12-ring pore zeolite material obtained in (2'.1); (2'.3) Calcining the mixture obtained in (2'.2) to obtain a 12-ring pore zeolite material containing a first metal, preferably iron; (2'.4) combining water with a 12-ring small pore zeolite material comprising a first metal, more preferably iron, and more preferably an organic acid, more preferably tartaric acid; (2'.5) adding a second metal-containing 10-ring pore zeolitic material, more preferably a 10-ring pore zeolitic material as defined above, to the mixture obtained in (2'.4); (2'.6) adding to the mixture obtained in (2'.5) a source of an oxide binder, more preferably colloidal silica; (2'.7) Adding an additive to the mixture obtained in (2'.6); It is more preferred that the composition contains:

[0125] The drying by (4') is preferably carried out in a gas atmosphere at a temperature in the range of 100 to 160°C, more preferably in the range of 120 to 140°C, and the gas atmosphere preferably contains oxygen, and even more preferably is air.

[0126] The drying in (4') is preferably carried out for a duration in the range of 5 minutes to 2 hours, more preferably 10 minutes to 1 hour.

[0127] The firing in (5') is preferably carried out in a gas atmosphere at a temperature in the range of 450 to 700°C, more preferably in the range of 500 to 600°C, and the gas atmosphere preferably contains oxygen, and even more preferably is air.

[0128] The firing in (5') is preferably carried out for a duration in the range of 5 minutes to 2 hours, more preferably 10 minutes to 1 hour.

[0129] The above method preferably comprises steps (1'), (2'), (3'), (4') and (5').

[0130] The present invention further relates to a catalyst for the selective catalytic reduction of nitrogen oxides, more preferably to a catalyst for the selective catalytic reduction of nitrogen oxides according to the invention, a catalyst for the selective catalytic reduction of nitrogen oxides obtainable or obtained by the process according to the invention.

[0131] The present invention provides a catalyst for selective catalytic reduction of nitrogen oxides, comprising: a first catalyst for the selective catalytic reduction of nitrogen oxides according to the invention as defined in item II, in which the coating of the first catalyst for the selective catalytic reduction of nitrogen oxides according to the invention as defined in item II is preferably the first coating (ii) as defined in item I, and A second catalyst for the selective catalytic reduction of nitrogen oxides, a substrate having 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 interior wall of the flow-through substrate extending therethrough; a coating disposed on the surface of the inner wall of the substrate, the coating being the second coating (iii) defined in item I; A second catalyst comprising: Including, wherein the first catalyst is disposed upstream of the second catalyst; and Here, the gap between the substrate of the first catalyst and the substrate of the second catalyst that are placed side by side is preferably less than 0.2 inches, and more preferably there is no gap between them. Regarding catalysts.

[0132] The substrate of the first catalyst is preferably defined as the substrate defined in item I. The substrate of the second catalyst is preferably defined as the substrate defined in item I.

[0133] It is more preferable that the substrate for the first catalyst and the substrate for the second catalyst have the same chemical composition, physical properties, and dimensions.

[0134] The present invention will be described by the first series of embodiments set forth below and the combinations resulting from the dependency and backward references of the embodiments set forth therein. The first series of embodiments can also be combined with the second series of embodiments described below. In particular, it should be noted that in clauses where a range of embodiments is mentioned, for example, in connection with the term "the catalyst according to any one of embodiments 1 to 4," it is intended to explicitly disclose to those skilled in the art all embodiments included within this range, i.e., the wording of this term should be understood as synonymous with "the catalyst according to any one of embodiments 1, 2, 3, and 4." Furthermore, it should be explicitly pointed out that the following series of embodiments is not a set of claims in the patent claims that determine the scope of protection, but rather provides a well-organized description of the general and preferred aspects of the present invention.

[0135] 1. A catalyst for selective catalytic reduction of nitrogen oxides, (i) a substrate having 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 interior wall of the flow-through substrate extending therethrough; (ii) a first coating comprising a 12-ring pore zeolite material comprising a first metal, the first metal being one or more of copper and iron, the 12-ring pore zeolite material comprising the first metal in an amount of z1% by weight, calculated by dividing the mass of the first metal, calculated as CuO and Fe2O3, by the mass of the 12-ring pore zeolite material comprising the first metal; (iii) a second coating comprising an eight-ring pore zeolite material containing a second metal, the second metal being one or more of copper and iron, wherein the eight-ring pore zeolite material contains the second metal in an amount of z2% by weight, calculated by dividing the mass of the second metal, calculated as CuO and Fe2O3, by the mass of the eight-ring pore zeolite material containing the second metal. Equipped with wherein the first coating is disposed on a surface of an inner wall of the substrate, the surface defining an interface between the inner wall and the passageway, and extends (covers) x% of the axial length of the substrate from the inlet end toward the outlet end of the substrate, where x is in the range of 10 to 75; the second coating extends (covers) y% of the axial length of the substrate from the outlet end toward the inlet end, where y is in the range of 25 to 90; wherein the ratio z1:z2 is in the range of 0.5:1 to 0.95:1.

[0136] 2. The catalyst of embodiment 1, wherein x is in the range of 20 to 72, preferably in the range of 22 to 70, and more preferably in the range of 25 to 68.

[0137] 3. The catalyst according to embodiment 1 or 2, wherein y is in the range of 27 to 80, preferably in the range of 30 to 78, more preferably in the range of 32 to 75.

[0138] 4. The catalyst of any one of embodiments 1 to 3, wherein y is 100-x.

[0139] 5. The catalyst of any one of embodiments 1 to 4, wherein the second coating is disposed on a surface of the inner wall of the substrate.

[0140] 6.x < y, where x ranges from 10 to 45, preferably from 20 to 40, more preferably from 25 to 35, or x > y, where x ranges from 55 to 75, preferably from 60 to 72, more preferably from 62 to 70, and even more preferably from 63 to 68, the catalyst according to any one of Embodiments 1 to 5.

[0141] 7. The catalyst according to any one of Embodiments 1 to 6, wherein there is no overlap between the first coating and the second coating.

[0142] 8. The 12-membered ring zeolite material contained in the first coating is selected from the group consisting of BEA, FAU, USY, GME, MOR, OFF, mixtures of two or more thereof, and mixed types of two or more thereof. Preferably, it has a framework type selected from the group consisting of BEA, FAU, mixtures of two or more thereof, and mixed types of two or more thereof. More preferably, the 12-membered ring zeolite material contained in the first coating has a framework type BEA. The catalyst according to any one of Embodiments 1 to 7.

[0143] 9. The 12-membered ring zeolite material contained in the first coating contains a first metal which is iron, and the amount of iron contained in the 12-membered ring zeolite material containing the first metal is z1 mass% calculated by dividing the mass of the first metal calculated as Fe2O3 by the mass of the 12-membered ring zeolite material containing the first metal. Here, z1 is preferably in the range of 1.0 to 10, more preferably in the range of 1.5 to 8, more preferably in the range of 2 to 6, more preferably in the range of 3 to 5, and more preferably in the range of 3.5 to 4.8. The catalyst according to any one of Embodiments 1 to 8.

[0144] 10. 0 to 0.001 mass%, preferably 0 to 0.0001 mass%, and even more preferably 0 to 0.00001 mass% of the first metal consists of copper calculated as CuO. Here, the 12-membered ring zeolite material contained in the first coating preferably does not contain copper. The catalyst according to Embodiment 9.

[0145] 11. The catalyst according to any one of embodiments 1 to 10, wherein 95 to 100% by weight, preferably 98 to 100% by weight, and more preferably 99 to 100% by weight, of the framework structure of the 12-ring pore zeolite material consists of Si, Al, O, and optionally H, wherein the molar ratio of Si to Al, calculated as molar SiO2:Al2O3, in the framework structure is preferably in the range of 2:1 to 37:1, more preferably in the range of 3:1 to 35:1, more preferably in the range of 4:1 to 20:1, more preferably in the range of 5:1 to 15:1, and more preferably in the range of 6:1 to 12:1.

[0146] 12. The catalyst of any one of embodiments 1 to 11, wherein the 12-ring pore zeolitic material is prepared by a template-free process.

[0147] 13. The catalyst of any one of embodiments 1 to 12, wherein the first coating comprises the 12-ring pore zeolite material containing the first metal in an amount in the range of 70 to 98% by weight, preferably in the range of 75 to 97% by weight, further preferably in the range of 80 to 95% by weight, and even more preferably in the range of 85 to 92% by weight, based on the weight of the first coating.

[0148] 14. The catalyst of any one of embodiments 1 to 13, wherein the first coating further comprises a 10-ring pore zeolite material comprising a third metal, the third metal being one or more of copper and iron, and the third metal is more preferably iron.

[0149] 15. The catalyst of embodiment 14, wherein the 10-ring pore zeolitic material in the first coating has a framework type selected from the group consisting of MFI, MWW, AEL, HEU, FER, AFO, mixtures of two or more thereof, and mixed types of two or more thereof, and the 10-ring pore zeolitic material in the first coating preferably has framework type MFI.

[0150] 16. The catalyst of embodiment 14 or 15, wherein the 10-ring pore zeolitic material in the first coating comprises a third metal that is iron, and the 10-ring pore zeolitic material preferably comprises iron in an amount in the range of 0.5 to 9 wt.%, preferably in the range of 1 to 7 wt.%, more preferably in the range of 1.5 to 6 wt.%, more preferably in the range of 2 to 5 wt.%, more preferably in the range of 2.5 to 4.5 wt.% (calculated by dividing the mass of the third metal, calculated as Fe2O3, by the mass of the 10-ring pore zeolitic material containing the third metal).

[0151] 17. The catalyst of embodiment 16, wherein 0 to 0.001 wt. %, preferably 0 to 0.0001 wt. %, and more preferably 0 to 0.00001 wt. % of the third metal consists of copper, calculated as CuO, and wherein the 10-ring pore zeolite material in the first coating is preferably copper-free.

[0152] 18. The catalyst according to any one of embodiments 14 to 17, wherein 95 to 100% by weight, preferably 98 to 100% by weight, more preferably 99 to 100% by weight, of the framework structure of the 10-ring pore zeolitic material consists of Si, Al, O, and optionally H, wherein the molar ratio of Si to Al in the framework structure, calculated as molar SiO2:Al2O3, is preferably in the range of 2:1 to 60:1, more preferably in the range of 5:1 to 50:1, more preferably in the range of 10:1 to 40:1, more preferably in the range of 15:1 to 35:1, more preferably in the range of 20:1 to 30:1, more preferably in the range of 23:1 to 29:1.

[0153] 19. The catalyst of any one of embodiments 14 to 18, wherein the first coating comprises a 10-ring pore zeolite material containing a third metal in an amount in the range of 1 to 8 wt.%, preferably in the range of 2 to 7 wt.%, more preferably in the range of 3 to 6 wt.%, based on the weight of the first coating.

[0154] 20. The catalyst of any one of the preceding embodiments, wherein the first coating further comprises an oxide binder, preferably comprising one or more of zirconia, alumina, titania, silica, and mixed oxides comprising two or more of Zr, Al, Ti, and Si; more preferably comprising one or more of silica, alumina, and zirconia; more preferably comprising one or more of silica and zirconia; more preferably comprising silica.

[0155] 21. The catalyst of embodiment 20, wherein the first coating comprises an oxide binder in an amount in the range of 0.5 to 8% by weight, more preferably in the range of 2 to 7% by weight, and even more preferably in the range of 3 to 6% by weight, based on the weight of the first coating.

[0156] 22. The catalyst according to any one of the preceding embodiments, wherein 95 to 100%, preferably 98 to 100%, more preferably 99 to 100%, more preferably 99.5 to 100%, by weight, of the first coating consists of a 12-ring pore zeolite material comprising a first metal, the first metal being one or more of copper and iron, and preferably one or more of a 10-ring pore zeolite material comprising a third metal as defined in any one of embodiments 14 to 19 and an oxide binder as defined in embodiment 20 or 21, more preferably a 10-ring pore zeolite material comprising a third metal as defined in any one of embodiments 14 to 19 and an oxide binder as defined in embodiment 20 or 21.

[0157] 23. The first coating is 1.5 to 5 g / in 3 in the range of 2 to 4 g / in 3 in the range of 2.5 to 3.5 g / in 3 23. The catalyst of any one of embodiments 1 to 22, wherein the catalyst is present in the catalyst at a loading in the range of

[0158] 24. The catalyst of any one of embodiments 1 to 23, wherein up to 10 ppm of the first coating consists of platinum, preferably 0 to 5 ppm, even more preferably 0 to 2 ppm, more preferably 0 to 1 ppm, and more preferably 0 to 0.5 ppm, and more preferably consists of platinum, palladium, and rhodium, and more preferably platinum group metals.

[0159] 25. The catalyst of any one of embodiments 1 to 24, wherein 0 to 0.01 wt. %, preferably 0 to 0.001 wt. %, and more preferably 0 to 0.0001 wt. % of the first coating consists of an 8-ring pore zeolite material.

[0160] 26. The catalyst of any one of embodiments 1 to 25, wherein 0 to 0.001 wt. % of the first coating consists of copper, calculated as CuO, preferably 0 to 0.0001 wt. %, and more preferably 0 to 0.00001 wt. %.

[0161] 27. The first coating (ii) has an ammonia storage capacity A1 of at least 2.1 mmol / g, preferably in the range of 2.2 to 10.0 mmol / g, more preferably in the range of 2.5 to 5.0 mmol / g. (NH3) (The ammonia storage capacity is determined as defined in Reference Example 1).

[0162] 28. The catalyst of any one of embodiments 1 to 27, wherein the 8-ring pore zeolite material in the second coating 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, 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 and AEI, and more preferably having framework type CHA.

[0163] 29. The catalyst of any one of embodiments 1 to 28, wherein the 8-ring pore zeolite material in the second coating comprises a second metal that is copper, and the 8-ring pore zeolite material comprises z2 wt. % copper, calculated by dividing the mass of the second metal, calculated as CuO, by the mass of the 8-ring pore zeolite material containing the second metal, and z2 is preferably in the range of 2.0 to 15, more preferably in the range of 3 to 10, more preferably in the range of 4 to 8, more preferably in the range of 4.5 to 7, and more preferably in the range of 4.9 to 6.

[0164] 30. The catalyst of embodiment 29, wherein 0 to 0.001 wt. % of the first metal is iron, calculated as Fe2O3, more preferably 0 to 0.0001 wt. %, and even more preferably 0 to 0.00001 wt. %, of the first metal; and wherein the 8-ring pore zeolite material in the second coating is preferably iron-free.

[0165] 31. The catalyst according to any one of embodiments 1 to 30, wherein 95 to 100 wt%, preferably 98 to 100 wt%, and more preferably 99 to 100 wt% of the framework structure of the 8-ring pore zeolitic material consists of Si, Al, O, and optionally H, wherein the molar ratio of Si to Al, calculated as molar SiO:AlO in the framework structure, is preferably in the range of 2:1 to 50:1, more preferably in the range of 2:1 to 45:1, more preferably in the range of 10:1 to 35:1, more preferably in the range of 15:1 to 25:1, and more preferably in the range of 16:1 to 22:1.

[0166] 32. The catalyst of any one of embodiments 1 to 31, wherein the second coating comprises the 8-ring pore zeolite material comprising the second metal in an amount in the range of 85 to 99 wt.%, more preferably in the range of 90 to 98 wt.%, more preferably in the range of 92 to 97 wt.%, based on the weight of the second coating.

[0167] 33. The catalyst of any one of embodiments 1-32, wherein the second coating further comprises an oxide binder, preferably comprising one or more of zirconia, alumina, titania, silica, and mixed oxides comprising two or more of Zr, Al, Ti, and Si; more preferably comprising one or more of silica, alumina, and zirconia; more preferably comprising one or more of alumina and zirconia; more preferably comprising zirconia.

[0168] 34. The catalyst of embodiment 33, wherein the second coating comprises an oxide binder in an amount in the range of 0.5 to 8% by weight, preferably in the range of 2 to 7% by weight, and more preferably in the range of 3 to 6% by weight, based on the weight of the first coating.

[0169] 35. The catalyst of any one of embodiments 1 to 34, wherein 95 to 100 wt. %, preferably 98 to 100 wt. %, even more preferably 99 to 100 wt. %, and even more preferably 99.5 to 100 wt. % of the second coating consists of an 8-ring pore zeolite material containing a second metal that is at least one of copper and iron, more preferably copper, and an oxide binder, preferably as defined in embodiment 33 or 34.

[0170] 36. The second coating is 1.5 to 5 g / in 3 range, preferably 1.75 to 4 g / in 3 in the range of 2 to 3.5 g / in 3 36. The catalyst of any one of embodiments 1 to 35, wherein the catalyst is present in the catalyst at a loading in the range of

[0171] 37. The catalyst of any one of embodiments 1 to 36, wherein up to 10 ppm, preferably 0 to 5 ppm, even more preferably 0 to 2 ppm, more preferably 0 to 1 ppm, more preferably 0 to 0.5 ppm of the second coating consists of platinum, preferably consisting of platinum, palladium, and rhodium, more preferably consisting of platinum group metals.

[0172] 38. The catalyst of any one of embodiments 1 to 37, wherein 0 to 0.01 wt. %, preferably 0 to 0.001 wt. %, and more preferably 0 to 0.0001 wt. % of the second coating consists of a 12-ring pore zeolite material.

[0173] 39. The catalyst of any one of embodiments 1 to 38, wherein 0 to 0.01 wt. %, preferably 0 to 0.001 wt. %, and more preferably 0 to 0.0001 wt. % of the second coating consists of a 10-ring pore zeolite material.

[0174] 40. The catalyst of any one of embodiments 1 to 39, wherein 0 to 0.001 wt. % of the second coating consists of iron, calculated as Fe2O3, preferably 0 to 0.0001 wt. %, and more preferably 0 to 0.00001 wt. %.

[0175] 41. The second coating (iii) has an ammonia storage capacity A2 of less than 2 mmol / g, preferably in the range of 0.5 to 1.99 mmol / g, more preferably in the range of 1 to 1.95 mmol / g. (NH3) 41. The catalyst of any one of embodiments 1 to 40, wherein the ammonia storage capacity is determined as defined in Reference Example 1.

[0176] 42. The catalyst of any one of embodiments 1-41, wherein the substrate is a flow-through substrate or a wall-flow filter substrate, preferably a flow-through substrate.

[0177] 43. The catalyst of embodiment 42, wherein the flow-through substrate comprises, preferably consists of, a ceramic material, preferably comprising, or more preferably consisting of, one or more of alumina, silica, silicates, aluminosilicates, preferably cordierite or mullite, aluminotitanate, silicon carbide, zirconia, magnesia, preferably spinel, and titania, more preferably one or more of silicon carbide and cordierite, more preferably cordierite.

[0178] 44. The catalyst of any one of embodiments 1 to 43, wherein the substrate has a substrate length in the range of 1 to 15 inches, preferably in the range of 2 to 10 inches.

[0179] 45. The catalyst of any one of embodiments 1 to 44, wherein the substrate has a substrate width in the range of 0.5 to 3 inches, preferably in the range of 0.75 to 2 inches.

[0180] 46. The catalyst of any one of embodiments 1 to 45, wherein the catalyst comprises, and preferably consists of, a substrate (i), a first coating (ii), and a second coating (iii).

[0181] 47. The catalyst of any one of embodiments 1 to 45, wherein the substrate comprises a first upstream substrate and a second downstream substrate, the first coating (ii) disposed on the first upstream substrate, and the second coating (ii) disposed on the second downstream substrate, and wherein there is preferably a gap of less than 0.2 inches, and more preferably no gap, between the juxtaposed first upstream substrate and second downstream substrate.

[0182] 48. The first coating (ii) has an ammonia storage capacity A1 (NH3) and the second coating (iii) has an ammonia storage capacity A2 (NH3) A1 (NH3) A2 (NH3) 48. The catalyst according to any one of embodiments 1 to 47, wherein the ammonia storage capacity is determined as defined in Reference Example 1.

[0183] 49.A1 (NH3) :A2 (NH3) in the range of 1.25:1 to 3:1, preferably in the range of 1.3:1 to 2:1, and more preferably in the range of 1.35:1 to 1.9:1.

[0184] 50. A method for producing a catalyst for selective catalytic reduction of nitrogen oxides according to any one of embodiments 1 to 49, comprising: (1) providing a substrate having 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 interior wall of the flow-through substrate extending therethrough; (2) preparing a first mixture comprising water and a 12-ring pore zeolite material comprising a first metal, the first metal being one or more of copper and iron, wherein the 12-ring pore zeolite material comprises the first metal in an amount of z1% by weight, calculated by dividing the mass of the first metal, calculated as CuO and Fe2O3, by the mass of the 12-ring pore zeolite material comprising the first metal; (3) disposing the first mixture obtained in (2) on the inner wall surface of the substrate prepared in (1) over x% of the axial length of the substrate from the inlet end to the outlet end of the substrate, where x is in the range of 10 to 75; (4) drying the mixture-treated substrate from (3) to obtain a substrate having a first coating disposed thereon; and optionally, baking; (5) preparing a second mixture comprising water and an 8-ring pore zeolite material containing a second metal, the second metal being one or more of copper and iron, wherein the 8-ring pore zeolite material contains z2% by weight of the second metal, calculated as the mass of the second metal, calculated as CuO and Fe2O3, divided by the mass of the 8-ring pore zeolite material containing the second metal; (6) disposing the second mixture obtained in (5) on the substrate having the first coating disposed thereon from the outlet end of the substrate toward the inlet end thereof over y% of the axial length of the substrate, where y is in the range of 25 to 90; (7) drying the mixture-treated substrate obtained in (6) to obtain a substrate having the first coating and the second coating disposed thereon; (8) Calcining the substrate having the first coating and the second coating disposed thereon obtained in (7) to obtain a catalyst; Including, wherein the ratio z1:z2 is in the range of 0.5:1 to 0.95:1.

[0185] 51.(2) further states, (2.1) Preparing a 12-ring pore zeolite material, preferably a 12-ring pore zeolite material as defined in any one of embodiments 8 to 12; (2.2) mixing a source of a first metal, preferably an iron salt, with the 12-ring pore zeolite material obtained in (2.1); (2.3) Calcining the mixture obtained in (2.2) to obtain a 12-ring pore zeolite material containing a first metal, preferably iron; (2.4) The method of embodiment 50, comprising admixing water, a 12-ring pore zeolite material comprising a first metal, preferably comprising iron, and preferably an organic acid, more preferably tartaric acid.

[0186] 52.(2) further states, (2.5) adding a 10-ring pore zeolitic material containing a third metal, preferably a 10-ring pore zeolitic material as defined in any one of embodiments 15 to 18, to the mixture obtained in (2.4); (2.6) preferably adding a source of oxide binder, preferably colloidal silica, to the mixture obtained in (2.5); (2.7) The process of embodiment 51, more preferably comprising adding an additive to the mixture obtained in (2.6).

[0187] 53. The method according to any one of embodiments 50 to 52, wherein the drying according to (4) is carried out in a gas atmosphere having a temperature in the range of 100 to 160°C, preferably in the range of 120 to 140°C, and the gas atmosphere preferably contains oxygen, more preferably is air.

[0188] 54. The method according to any one of embodiments 50 to 53, wherein the drying according to (4) is carried out for a duration ranging from 5 minutes to 2 hours, preferably from 10 minutes to 1 hour.

[0189] 55. The method according to any one of embodiments 50 to 54, wherein after drying, the calcination described in (4) is carried out in a gas atmosphere having a temperature in the range of 450 to 700 °C, preferably in the range of 500 to 600 °C, and the gas atmosphere preferably contains oxygen, more preferably is air.

[0190] 56. The method according to any one of embodiments 50 to 55, wherein after drying, the calcination according to (4) is carried out for a duration in the range of 5 minutes to 2 hours, preferably in the range of 10 minutes to 1 hour.

[0191] 57.(5) is (5.1) Preparing an 8-ring pore zeolitic material containing a second metal, which is one or more of copper and iron, preferably copper, preferably as defined in any one of embodiments 28 to 31; (5.2) mixing water with the 8-ring pore zeolite material obtained in (5.1) containing a second metal, which is one or more of copper and iron, preferably copper; (5.3) The method of any one of embodiments 50 to 56, comprising adding a source of oxide binder, preferably zirconium acetate, to the mixture obtained in (5.2).

[0192] 58. The method according to any one of embodiments 50 to 57, wherein the drying according to (7) is carried out in a gas atmosphere having a temperature in the range of 100 to 160°C, preferably in the range of 120 to 140°C, and the gas atmosphere preferably contains oxygen, more preferably is air.

[0193] 59. The method according to any one of embodiments 50 to 58, wherein the drying according to (7) is carried out for a duration ranging from 5 minutes to 2 hours, preferably from 10 minutes to 1 hour.

[0194] 60. The method according to any one of embodiments 50 to 59, wherein after drying, the calcination described in (7) is carried out in a gas atmosphere having a temperature in the range of 400 to 600°C, preferably in the range of 450 to 550°C, and the gas atmosphere preferably contains oxygen, more preferably is air.

[0195] 61. After drying, the firing described in (7) is carried out for a duration in the range of 5 minutes to 2 hours, preferably in the range of 10 minutes to 1 hour, according to the method of any one of Embodiments 50 to 60.

[0196] 62. x is in the range of 20 to 72, preferably in the range of 22 to 70, more preferably in the range of 25 to 68, according to the method of any one of Embodiments 50 to 61.

[0197] 63. y is in the range of 27 to 80, preferably in the range of 30 to 78, more preferably in the range of 32 to 75, according to the method of any one of Embodiments 50 to 62.

[0198] 64. y is 100 - x, according to the method of any one of Embodiments 50 to 63.

[0199] 65. The second coating is disposed on the surface of the inner wall of the substrate, according to the method of any one of Embodiments 50 to 64.

[0200] 66. x < y, and x is in the range of 10 to 45, preferably in the range of 20 to 40, more preferably in the range of 25 to 35; or x > y, and x is in the range of 55 to 75, preferably in the range of 60 to 72, more preferably in the range of 62 to 70, even more preferably in the range of 63 to 68, according to the method of any one of Embodiments 50 to 65.

[0201] 67. There is no overlap between the first coating and the second coating, according to the method of any one of Embodiments 50 to 66.

[0202] 68. Consisting of (1), (2), (3), (4), (5), (6) and (7), according to the method of any one of Embodiments 50 to 68.

[0203] 69. A catalyst for the selective catalytic reduction of nitrogen oxides obtainable or obtained by the method according to any one of embodiments 50 to 68, preferably the catalyst for the selective catalytic reduction of nitrogen oxides according to any one of embodiments 1 to 49.

[0204] 70. An exhaust gas treatment system for treating exhaust gas emitted from a combustion engine, preferably a diesel engine, comprising one or more catalysts for selective catalytic reduction of nitrogen oxides according to any one of embodiments 1 to 49 and 69, and one or more of a diesel oxidation catalyst, a catalyzed soot filter, and an ammonia oxidation catalyst.

[0205] 71. A diesel oxidation catalyst, a catalyzed soot filter, and one or more catalysts for selective catalytic reduction of nitrogen oxides according to any one of embodiments 1 to 49 and 69, The system of embodiment 70, wherein the diesel oxidation catalyst is located upstream of the catalyzed soot filter, and the catalyzed soot filter is located upstream of one or more catalysts for selective catalytic reduction of nitrogen oxides according to any one of embodiments 1 to 49 and 69.

[0206] 72. The system of embodiment 71, wherein a catalyzed soot filter is disposed upstream of two catalysts for the selective catalytic reduction of nitrogen oxides of any one of embodiments 1 to 49 and 69, and the two catalysts for the selective catalytic reduction of nitrogen oxides are disposed in parallel with each other.

[0207] 73. The system of embodiment 72, further comprising two ammonia oxidation catalysts, each ammonia oxidation catalyst being disposed downstream of one catalyst for selective catalytic reduction of nitrogen oxides of any one of embodiments 1 to 49 and 69.

[0208] 74. A vehicle comprising the catalyst for selective catalytic reduction of nitrogen oxides according to any one of embodiments 1 to 49 and 69 and a catalyzed soot filter; 71. The system of embodiment 70, wherein the catalyzed soot filter is disposed downstream of the catalyst for selective catalytic reduction of nitrogen oxides of any one of embodiments 1 to 49 and 69.

[0209] 75. Further comprising a diesel oxidation catalyst, the diesel oxidation catalyst being positioned downstream of the catalyst for selective catalytic reduction of nitrogen oxides according to any one of embodiments 1 to 49 and 69 and upstream of the catalyzed soot filter; 75. The system of embodiment 74, wherein preferably further comprising an ammonia oxidation catalyst disposed downstream of the catalyzed particulate filter.

[0210] 76. Use of the catalyst according to any one of embodiments 1 to 49 and 69 for the selective catalytic reduction of nitrogen oxides contained in an exhaust gas stream, preferably from a diesel engine.

[0211] 77. Use of an exhaust gas treatment system according to any one of embodiments 70 to 75 for treating an exhaust gas stream from a diesel engine.

[0212] 78. A method for selective catalytic reduction of NOx, wherein the NOx is contained in an exhaust gas stream, (1) providing an exhaust gas stream, preferably an exhaust gas stream from a diesel engine; (2) A method comprising passing the exhaust gas stream provided in (1) through the catalyst of any one of embodiments 1 to 49 and 69.

[0213] 79. A method for treating an exhaust gas stream from a diesel engine, comprising: (1') providing said exhaust gas stream; (2') A method comprising passing the exhaust gas stream provided in (1') through the exhaust gas treatment system of any one of embodiments 70-75.

[0214] Next, the present invention will be described by the following second series of embodiments, combinations of the dependencies and back-references shown therein. The second series of embodiments can also be combined with the first series of embodiments. In particular, in a term that refers to a plurality of embodiments within a certain range, such as "a catalyst according to any one of Embodiments 1' to 3'", it is intended to explicitly disclose to those skilled in the art all the embodiments included within this range. That is, it should be noted that the language of this term should be understood to be synonymous with "a catalyst according to any one of Embodiments 1', 2', and 3'". Further, it is explicitly pointed out that the following series of embodiments present a systematic and appropriate explanation of the general and preferred aspects of the present invention, rather than a set of claims in the claims defining the scope of protection.

[0215] 1’. A catalyst for selective catalytic reduction of nitrogen oxides, comprising: a substrate having 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 the inner wall of the through-flow substrate extending therethrough; a coating disposed on the surface of the inner wall of the substrate, on the surface defining the interface between the inner wall and the passages, the coating comprising a 12-ring zeolite material containing at least one first metal selected from copper and iron, wherein the 12-ring zeolite material contains the first metal in an amount of z mass% calculated by dividing the mass of the first metal calculated as CuO and Fe2O3 by the mass of the 12-ring zeolite material containing the first metal; and wherein the coating further comprises a 10-ring zeolite material containing at least one second metal selected from copper and iron, and the 10-ring zeolite material contains the second metal in an amount of y mass% calculated by dividing the mass of the second metal calculated as CuO and Fe2O3 by the mass of the 10-ring zeolite material containing the second metal; wherein y is in the range of 0.5 to 9 and y < z.

[0216] 2'. The catalyst of embodiment 1', wherein the coating extends over 90-100%, preferably 95-100%, and more preferably 98-100% of the axial length of the substrate.

[0217] 3'. The catalyst of embodiment 1' or 2', wherein the 12-ring pore zeolite material comprised in the coating has a framework type selected from the group consisting of BEA, FAU, USY, GME, MOR, OFF, mixtures of two or more thereof, and mixed types of two or more thereof, more preferably a framework type selected from the group consisting of BEA, FAU, mixtures of two or more thereof, and mixed types of two or more thereof, even more preferably framework type BEA.

[0218] 4'. The catalyst of any one of embodiments 1' to 3', wherein the 12-ring pore zeolite material in the coating comprises a first metal that is iron, and the 12-ring pore zeolite material comprises z wt. % iron, calculated by dividing the mass of the first metal, calculated as Fe2O3, by the mass of the 12-ring pore zeolite material comprising the first metal, where z is preferably in the range of 1.0 to 10, more preferably 1.5 to 8, more preferably 2 to 6, more preferably 3 to 5, or more preferably 3.5 to 4.8.

[0219] 5'. The catalyst of embodiment 4', wherein 0 to 0.001 wt. % of the first metal consists of copper, calculated as CuO, preferably 0 to 0.0001 wt. %, and more preferably 0 to 0.00001 wt. %, and wherein the 12-ring pore zeolite material included in the coating is preferably copper-free.

[0220] 6'. The catalyst according to any one of embodiments 1' to 5', wherein 95 to 100% by weight, preferably 98 to 100% by weight, and more preferably 99 to 100% by weight, of the framework structure of the 12-ring pore zeolite material consists of Si, Al, O, and optionally H, wherein the molar ratio of Si to Al, calculated as molar SiO2:Al2O3, in the framework structure is preferably in the range of 2:1 to 37:1, more preferably in the range of 3:1 to 35:1, more preferably in the range of 4:1 to 20:1, more preferably in the range of 5:1 to 15:1, and more preferably in the range of 6:1 to 12:1.

[0221] 7'. The catalyst of any one of embodiments 1' to 6', wherein the 12-ring pore zeolitic material is prepared by a template-free process.

[0222] 8'. The catalyst of any one of embodiments 1' to 7', wherein the coating comprises the 12-ring pore zeolite material containing the first metal in an amount ranging from 70 to 98 wt.%, preferably from 75 to 97 wt.%, more preferably from 80 to 95 wt.%, and even more preferably from 85 to 92 wt.%, based on the weight of the coating.

[0223] 9'. The catalyst of any one of embodiments 1' to 8', wherein the 10-ring pore zeolitic material comprises a second metal that is iron.

[0224] 10'. The catalyst of any one of embodiments 1' to 9', wherein the 10-ring pore zeolite material in the coating has a framework type selected from the group consisting of MFI, MWW, AEL, HEU, FER, AFO, mixtures of two or more thereof, and mixed types of two or more thereof, wherein the 10-ring pore zeolite material in the coating preferably has framework type MFI.

[0225] 11'. The catalyst of any one of embodiments 1' to 10', wherein the 10-ring pore zeolite material in the coating comprises a second metal that is iron, and the 10-ring pore zeolite material comprises y wt. % iron, calculated by dividing the mass of the second metal, calculated as Fe2O3, by the mass of the 10-ring pore zeolite material comprising the second metal, where y is preferably in the range of 1 to 7, more preferably in the range of 1.5 to 6, more preferably in the range of 2 to 5, and more preferably in the range of 2.5 to 4.5.

[0226] 12'. The catalyst of embodiment 11', wherein 0 to 0.001 wt. % of the second metal is copper, calculated as CuO, preferably 0 to 0.0001 wt. %, and more preferably 0 to 0.00001 wt. %, and the 10-ring pore zeolite material contained in the coating is preferably copper-free.

[0227] 13'. The catalyst according to any one of embodiments 1' to 12', wherein 95 to 100 wt%, preferably 98 to 100 wt%, and more preferably 99 to 100 wt% of the framework structure of the 10-ring pore zeolite material consists of Si, Al, O, and optionally H, wherein the molar ratio of Si to Al in the framework structure, calculated as molar SiO2:Al2O3, is preferably in the range of 2:1 to 60:1, more preferably in the range of 5:1 to 50:1, more preferably in the range of 10:1 to 40:1, more preferably in the range of 15:1 to 35:1, more preferably in the range of 20:1 to 30:1, and more preferably in the range of 23:1 to 29:1.

[0228] 14'. The catalyst of any one of embodiments 1' to 13', wherein the coating comprises the 10-ring pore zeolite material comprising the second metal in an amount in the range of 1 to 8 wt.%, preferably in the range of 2 to 7 wt.%, more preferably in the range of 3 to 6 wt.%, based on the weight of the coating.

[0229] 15'. the coating further comprises an oxide binder, preferably comprising one or more of zirconia, alumina, titania, silica, and mixed oxides comprising two or more of Zr, Al, Ti, and Si, more preferably comprising one or more of silica, alumina, and zirconia, more preferably comprising one or more of silica and zirconia, and even more preferably comprising silica; Catalyst according to any one of embodiments 1' to 14', wherein the coating preferably comprises an oxide binder in an amount in the range of 0.5 to 8 wt.%, more preferably in the range of 2 to 7 wt.%, and even more preferably in the range of 3 to 6 wt.%, based on the weight of the coating.

[0230] 16'. The catalyst according to any one of embodiments 1' to 15', wherein 95 to 100% by weight, preferably 98 to 100% by weight, even more preferably 99 to 100% by weight, and even more preferably 99.5 to 100% by weight of the coating consists of a 12-membered ring pore zeolite material containing a first metal that is at least one of copper and iron, more preferably iron, a 10-membered ring pore zeolite material containing a second metal that is at least one of copper and iron, more preferably iron, and an oxide binder preferably according to embodiment 15'.

[0231] 17. Coating: 1.5~5g / in 3 in the range of 2 to 4 g / in 3 in the range of 2.5 to 3.5 g / in 3 The catalyst of any one of embodiments 1' to 16', wherein the catalyst is present in the catalyst at a loading in the range of

[0232] 18′. The catalyst of any one of embodiments 1′ to 17′, wherein up to 10 ppm of the coating consists of platinum, preferably 0-5 ppm, even more preferably 0-2 ppm, more preferably 0-1 ppm, more preferably 0-0.5 ppm, of the coating consists of platinum, preferably consisting of platinum, palladium, and rhodium, more preferably consisting of platinum group metals.

[0233] 19'. The catalyst of any one of embodiments 1' to 18', wherein 0 to 0.01 wt. % of the coating is made of an 8-ring pore zeolite material, preferably 0 to 0.001 wt. %, and more preferably 0 to 0.0001 wt. %.

[0234] 20′. The catalyst of any one of embodiments 1′ to 19′, wherein 0 to 0.001% by weight of the coating consists of copper, calculated as CuO, preferably 0 to 0.0001% by weight, and more preferably 0 to 0.00001% by weight.

[0235] 21'. The coating has an ammonia storage capacity A1 of at least 2.1 mmol / g, preferably in the range of 2.2 to 10.0 mmol / g, more preferably in the range of 2.5 to 5.0 mmol / g. (NH3) (The ammonia storage capacity is determined as defined in Reference Example 1).

[0236] 22'. The catalyst of any one of embodiments 1' to 21', comprising a substrate and a coating.

[0237] 23'. A method for preparing the catalyst according to any one of embodiments 1' to 22', comprising: (1') providing a substrate having 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 interior wall of the flow-through substrate extending therethrough; (2’) Prepare a mixture comprising water and a 12-membered ring zeolite material containing at least one of copper and iron, wherein the 12-membered ring zeolite material contains the first metal in an amount of z mass% calculated by dividing the mass of the first metal calculated as CuO and Fe2O3 by the mass of the 12-membered ring zeolite material containing the first metal, and the mixture further contains a 10-membered ring zeolite material containing at least one of copper and iron as the second metal, where the 10-membered ring zeolite material contains the second metal in an amount of y mass% calculated by dividing the mass of the second metal calculated as CuO and Fe2O3 by the mass of the 10-membered ring zeolite material containing the second metal), (3’) Dispose the mixture obtained in (2’) over x% of the axial length of the substrate from the inlet end to the outlet end on the surface of the inner wall of the substrate prepared in (1’), where x ranges from 10 to 75, (4’) Dry the mixture-treated substrate obtained in (3’) to obtain a substrate with a coating disposed thereon, (5’) Bake the substrate with a coating disposed thereon obtained in (4’) to obtain a catalyst (including), where y ranges from 0.5 to 9 and y < z, a method.

[0238] 24’. (2’) further comprises (2’.1) Prepare a 12-membered ring zeolite material, preferably the 12-membered ring zeolite material defined in any one of embodiments 3’ to 7’ (2’.2) Mix a source of the first metal, preferably an iron salt, with the 12-membered ring zeolite material obtained in (2’.1) (2’.3) Bake the mixture obtained in (2’.2) to obtain a 12-membered ring zeolite material containing the first metal, preferably iron (2’.4) Mix water, the 12-membered ring zeolite material containing the first metal, preferably iron, and preferably an organic acid, more preferably tartaric acid (2'.5) adding a 10-ring pore zeolitic material containing a second metal, preferably a 10-ring pore zeolitic material as defined in any one of embodiments 10' to 13', to the mixture obtained in (2'.4); (2'.6) Preferably, adding a source of oxide binder, preferably colloidal silica, to the mixture obtained in (2'.5); (2'.7) More preferably, an additive is added to the mixture obtained in (2'.6). The method of embodiment 23', comprising:

[0239] 25'. The method according to embodiment 23' or 24', wherein the drying according to (4') is carried out in a gas atmosphere having a temperature in the range of 100 to 160°C, preferably in the range of 120 to 140°C, and the gas atmosphere preferably contains oxygen, more preferably air.

[0240] 26'. The method according to any one of embodiments 23' to 25', wherein the drying according to (4') is carried out for a duration ranging from 5 minutes to 2 hours, preferably from 10 minutes to 1 hour.

[0241] 27'. The method according to any one of embodiments 23' to 26', wherein the firing according to (5') is carried out in a gas atmosphere having a temperature in the range of 450 to 700°C, preferably in the range of 500 to 600°C, and the gas atmosphere preferably contains oxygen, more preferably air.

[0242] 28'. The method according to any one of embodiments 23' to 27', wherein the baking according to (5') is carried out for a duration ranging from 5 minutes to 2 hours, preferably from 10 minutes to 1 hour.

[0243] 29'. The method according to any one of embodiments 23' to 28', consisting of (1'), (2'), (3'), (4') and (5').

[0244] 30'. A catalyst for selective catalytic reduction of nitrogen oxides obtainable or obtained by the method according to any one of embodiments 23' to 28', preferably the catalyst for selective catalytic reduction of nitrogen oxides according to any one of embodiments 1' to 22'.

[0245] 31'. A catalyst for selective catalytic reduction of nitrogen oxides, A first catalyst for selective catalytic reduction of nitrogen oxides according to any one of embodiments 1' to 22'; A second catalyst for the selective catalytic reduction of nitrogen oxides, a substrate having 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 interior wall of the flow-through substrate extending therethrough; a coating disposed on the surface of the inner wall of the substrate, the coating being the second coating (iii) as defined in the first set of embodiments. a second catalyst comprising: Including, where: The coating of the catalyst for the selective catalytic reduction of nitrogen oxides according to any one of embodiments 1′ to 22′ is preferably the first coating (ii) as defined in the first series of embodiments, The first catalyst is disposed upstream of the second catalyst; A catalyst wherein the gap between the substrate of a first catalyst and the substrate of a second catalyst that are juxtaposed is preferably less than 0.2 inches, and more preferably there is no gap between them.

[0246] In the present invention, the "loading amount" (g / in 3 or g / ft 3 The term "mass of component / coating" refers to the mass of said component / coating per volume of substrate (on which said component / coating resides), where the volume of the substrate is the volume defined by the cross-sectional area of the substrate times the axial length of the substrate. For example, a volume extending over x% of the axial length of the substrate and having a mass of X g / in 3When referring to a first coating loading having a loading of 0.01, the loading is relative to the total substrate volume (in 3 ) refers to X grams of the first coating per x% of the total weight of the coating.

[0247] Furthermore, in the context of the present invention, the phrase "X is one or more of A, B, and C" (where X is a given feature and each of A, B, and C represents a specific implementation of said feature) should be understood as disclosing that X is either A or B or C, A and B, A and C, B and C, or A, B, and C. In this regard, it should be noted that those skilled in the art can convert the above abstract terms into concrete examples. For example, X is a chemical element and A, B, and C are specific elements such as Li, Na, and K, or 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 should be noted that those skilled in the art can extend the above terms to less specific implementations of said feature. For example, "X is one or more of A and B" discloses that X is A or B, or A and B. Also, it should be noted that the above terms may alternatively be expanded to more specific realizations of the feature, for example, "X is one or more of A, B, C, and D" discloses that X is any of 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, B, and C, or A, B, and D, or B, C, and D, or A, B, C, and D.

[0248] Furthermore, in the context of the present invention, the expression "surface of the interior wall" 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 which may contaminate the surface).

[0249] In the context of the present invention, the expression "consists of" in relation to the weight percent of one or more components refers to the weight percent amount of that component relative to 100 weight percent of the entity in question. For example, the phrase "0 to 0.001 weight percent of the first coating consists of platinum" indicates that of the 100 weight percent components that make up the coating, 0 to 0.001 weight percent is platinum.

[0250] The present invention will be further illustrated by the following Reference Examples, Comparative Examples, and Examples. [Example]

[0251] Reference Example 1: Ammonia storage capacity measurement The ammonia storage capacity of a given catalyst can be determined by the method described in U.S. Pat. No. 9,597,633. 6 The measurements were carried out by thermogravimetric analysis (TGA) as defined in B2.

[0252] Reference Example 2: Determination of particle size distribution by volume (Dv90) The particle size distribution was determined by static light scattering using a Sympatec HELOS (3200) & QUIXEL instrument. The optical density of the samples was less than 10%.

[0253] Reference example 3: BET specific surface area measurement The BET specific surface area was determined using liquid nitrogen according to DIN 66131 or DIN ISO 9277.

[0254] Reference Example 4: Application method To apply one or more coatings to a flow-through substrate, the flow-through substrate was dipped vertically into a portion of a given slurry over a specific length of the substrate equal to the desired length of the coating to be applied, thus bringing the slurry into contact with the wall of the substrate.

[0255] Reference Example 6: Preparation of selective catalytic reduction (SCR) catalyst (containing Fe-BEA) Slurry preparation: Fe-BEA (Dv90 5.15 μm, SiO2:Al2O3 molar ratio 39, BET specific surface area approximately 700 m) with an Fe content of 1.55 wt% (calculated as Fe2O3) based on the mass of the Fe-BEA. 2 1 / g) was dispersed in a solution of water and tartaric acid (1.3% by weight of tartaric acid based on the weight of Fe-BEA) to form a slurry. BEA zeolite was prepared via a template-based synthesis route. The resulting slurry was milled using a continuous milling device to obtain particles with a Dv90 value of approximately 5 micrometers.

[0256] Fe-MFI with an Fe content of 3.5 wt% (calculated as FeO) based on the mass of the Fe-MFI (Dv90 of 17.5 micrometers, SiO:AlO molar ratio of 27.5, BET specific surface area of approximately 385 m) 2 1 / g) was added to the Fe-BEA-containing slurry. The amount of Fe-MFI was calculated to be approximately 5.5% by weight based on the weight of Fe-BEA. Additionally, colloidal silica, a binder, was added to the mixture. The amount of colloidal silica was calculated to be approximately 5.4% by weight based on the weight of Fe-BEA. Finally, a viscosity agent (0.13% by weight based on the weight of Fe-BEA) was added. The resulting slurry was mixed and milled using a continuous milling device to obtain particles with a Dv90 value of approximately 5 micrometers. The pH of the aqueous phase of the slurry was measured and adjusted to approximately 3-3.5. The solids content of the slurry was 44% by weight.

[0257] The slurry obtained above was applied to an uncoated honeycomb flow-through monolith cordierite substrate (1 inch diameter x 2 inches length, 300 cells per square inch, and 5 mil wall thickness, cylindrical shape) along 100% of the substrate length according to the method described in Reference Example 4. The coated substrate was dried at 140°C for 30 minutes and calcined in air at 590°C for approximately 30 minutes (the coating / drying and calcination process was repeated once). The final coating loading on the calcined catalyst was approximately 3.2 g / in. 3 and Fe-BEA is 2.88 g / in 3, Fe-MFI is 0.16g / in 3 , silica is 0.1562g / in 3 The ammonia storage capacity of the coating measured in accordance with Reference Example 1 was 1.2 mmol / g.

[0258] Reference Example 7: Preparation of SCR catalyst (containing Cu-CHA) An aqueous solution of zirconium acetate was added to water. The amount of zirconium acetate was calculated so that the amount of zirconia in the coating, calculated as ZrO, was 5 wt.% based on the weight of Cu-chabazite. Additionally, Cu-chabazite (SiO:AlO molar ratio 18, BET specific surface area approximately 565 m) with a Cu content (calculated as CuO) of 5.1 wt.% based on the weight of chabazite was prepared. 2 / g) was added to a solution of zirconium acetate to form a mixture with a solids content of 46% by weight. Water was added, and the resulting slurry was milled using a continuous mill to obtain particles with a Dv90 value of approximately 7 micrometers. Further, a dispersant and an acid were added to the aqueous phase of the resulting slurry, and the pH value of the aqueous phase was adjusted to 4. Water was added to adjust the solids content of the slurry to 40% by weight.

[0259] The slurry obtained above was applied to an uncoated honeycomb flow-through monolith cordierite substrate (1 inch diameter x 1 inch length, 600 cells per square inch, 3 mil wall thickness, cylindrical shape) along 100% of the substrate length according to the method described in Reference Example 4. The coated substrate was dried at 140°C for 30 minutes and calcined in air at 450°C for approximately 30 minutes. The final coating loading on the calcined catalyst was approximately 2.75 g / in. 3 and Cu-CHA is 2.62 g / in 3 , ZrO2 is 0.13g / in 3 The ammonia storage capacity of the coating measured in accordance with Reference Example 1 was 1.9 mmol / g.

[0260] Example 1: Preparation of SCR catalyst Slurry preparation: Fe-BEA (Dv90 approximately 13.5 micrometers, SiO:AlO molar ratio 9.75, BET specific surface area approximately 612.5 m) with an Fe content of 4.6 mass % (calculated as FeO) based on the mass of the Fe-BEA. 2 The resulting slurry was dispersed in a solution of water and tartaric acid (1.3% by weight based on the weight of Fe-BEA) to form a slurry. The BEA zeolite was prepared by a template-free synthesis method. The resulting slurry was milled in a continuous mill to produce particles with a Dv90 value of approximately 5 micrometers.

[0261] Fe-MFI with an Fe content of 3.5 wt. % (calculated as FeO) based on the mass of the Fe-MFI (Dv90 of 17.5 micrometers, SiO:AlO molar ratio of 27.5, and BET specific surface area of approximately 385 m 2 1 / g) was added to the Fe-BEA-containing slurry. The amount of Fe-MFI was calculated to be approximately 5.5% by weight based on the weight of Fe-BEA. Additionally, colloidal silica, a binder, was added to the mixture. The amount of colloidal silica was calculated to be approximately 5.4% by weight based on the weight of Fe-BEA. Finally, a viscosity agent (0.13% by weight based on the weight of Fe-BEA) was added. The resulting slurry was mixed and milled using a continuous milling device to obtain particles with a Dv90 value of approximately 5 micrometers. The pH of the aqueous phase of the slurry was measured and adjusted to approximately 3-3.5. The solids content of the slurry was 39% by weight.

[0262] a) The slurry obtained above was applied to an uncoated honeycomb flow-through monolith cordierite substrate (a cylindrical shape with a diameter of 1 inch and a length of 2 inches, 600 cells per square inch, and a wall thickness of 3 mils) along 100% of the substrate length according to the method described in Reference Example 4. The coated substrate was dried at 140°C for 30 minutes and calcined in air at 590°C for approximately 30 minutes (the coating / drying and calcination process was repeated once or up to twice to reach the target loading described below).

[0263] The final coating loading on the calcined catalyst was approximately 3.2 g / in 3and Fe-BEA is 2.88 g / in 3 , Fe-MFI is 0.16g / in 3 , silica is 0.1562g / in 3 The ammonia storage capacity of the coating measured in accordance with Reference Example 1 was 2.8 to 3.0 mmol / g.

[0264] b) The slurry obtained above was applied to an uncoated honeycomb flow-through monolith cordierite substrate (a cylindrical shape having a diameter of 1 inch and a length of 2 inches, 300 cells per square inch, and a wall thickness of 5 mils) along 100% of the substrate length according to the method described in Reference Example 4. The coated substrate was dried at 140°C for 30 minutes and calcined in air at 590°C for approximately 30 minutes (the coating / drying and calcination process was repeated once or up to twice to reach the target loading described below).

[0265] The final coating loading on the calcined catalyst was approximately 3.2 g / in 3 and Fe-BEA is 2.88 g / in 3 , Fe-MFI is 0.16g / in 3 , silica is 0.1562g / in 3 The ammonia storage capacity of the coating measured in accordance with Reference Example 1 was 2.8 to 3.0 mmol / g.

[0266] Example 2: Testing of the catalysts of Example 1a) and Reference Example 6 - DeNOx performance and N2O production The catalysts of Example 1a) and Reference Example 6 were hydrothermally aged for 25 hours in an oven at 650°C. The deNOx (%) and NO (nitrous oxide) production (ppm) when the catalysts of Example 1a) and Reference Example 6 were used were measured (E-Lab evaluation).

[0267] Space velocity: 60000h -1 NOx = NO inlet concentration: 500 ppm / NH3 inlet concentration: 550 ppm / H2O: 10% by volume / O2: 10% by volume Test temperatures: 450, 400, 350, 300, 250, 225, 200, 180, and 150°C Summary of test procedures for lab reactor evaluation: 1. Adjust the maximum test temperature and feed gas composition.

[0268] 2. Stabilize the concentrations measured downstream of the catalyst under investigation.

[0269] 3. Measure NOx, NH3 and N2O concentrations at the catalyst outlet and use inlet concentrations from bypass measurements or reactor setup measurements.

[0270] 4. Move to the next lower temperature and repeat steps 2 and 3.

[0271] Calculation method: DeNOx: (NOx inlet - NOx outlet) / NOx inlet * 100 (unit: percent) N2O production: N2O outlet - N2O inlet (unit: ppm) The results are shown in Figures 1 and 2.

[0272] As can be seen from Figures 1 and 2, the catalyst of Example 1a) exhibits very low nitrous oxide production at temperatures between 150 and 450 °C, i.e., less than 0.5 ppm of NO, and at a T of about 250 °C 50 (deNOx) and a NOx conversion rate of about 98% at 450°C. In contrast, the catalyst of Reference Example 6 reveals that the NOx conversion rate is low under the same conditions. Therefore, the above example shows that the catalyst of the present invention makes it possible to improve the NOx conversion rate while showing a low NO production amount.

[0273] Example 3: Measurement of ammonia storage capacity for Example 1a), Reference Examples 6 and 7 The ammonia storage capacity or capacity of these catalyst coatings was measured under fresh conditions as defined in Reference Example 1. Specifically, the powder containing each coating component was measured, and the results are shown in Table 1 below.

[0274] [Table 1]

[0275] As can be seen from Table 1, the Fe-BEA catalyst of Example 1a) exhibits a much higher ammonia storage capacity than the Fe-BEA catalyst of Reference Example 6 (prior art). Thus, without being bound by theory, it is believed that the silica-to-alumina ratio and Fe content of the BEA zeolite material affect the ammonia storage capacity of the Fe-BEA catalyst. Furthermore, without wishing to be bound by any theory, it is believed that the method of preparing the BEA zeolite material, i.e., the template-free process for preparing the BEA zeolite material, also affects the ammonia storage capacity of the final catalyst. Furthermore, the Fe-BEA catalyst of Example 1a) also exhibits a much higher ammonia storage capacity than the Cu-CHA catalyst of Reference Example 7.

[0276] Example 4: SCR catalyst consisting of the catalyst of Example 1b) and the catalyst of Reference Example 7 An SCR catalyst was fabricated by combining the catalyst of Example 1b) and the catalyst of Reference Example 7, with the catalyst of Example 1b) upstream of the catalyst of Reference Example 7 and the catalyst of Reference Example 7 downstream of the catalyst of Example 1b) with no gap between the two catalysts. The length of the formed catalyst was 3 inches (2 inches - Example 1b) and 1 inch - Reference Example 7).

[0277] As a result, the upstream portion of the catalyst of Example 4, which used the catalyst of Example 1b), had an ammonia storage amount of 2.8 to 3.0 mmol / g, and the downstream portion of the catalyst of Example 4, which used the catalyst of Reference Example 7, had an ammonia storage amount of 1.9 mmol / g. The ammonia storage amount was determined as defined in Reference Example 1. The ammonia storage amount in the upstream region of the catalyst of Example 4 was higher than the ammonia storage amount in the downstream region of the catalyst.

[0278] Comparative Example 1: SCR catalyst consisting of the catalyst of Reference Example 6 and the catalyst of Reference Example 7 An SCR catalyst was prepared by combining the catalysts of Reference Example 6 and Reference Example 7 so that the catalyst of Reference Example 6 was located upstream of the catalyst of Reference Example 7 and the catalyst of Reference Example 7 was located downstream of the catalyst of Reference Example 6, with no gap between the two catalysts. The length of the prepared catalyst was 3 inches (2 inches - Reference Example 6, 1 inch - Reference Example 7).

[0279] As a result, the upstream portion of the catalyst of Comparative Example 1, which used the catalyst of Example 6, had an ammonia storage capacity of 1.2 mmol / g, and the downstream portion of the catalyst of Comparative Example 1, which used the catalyst of Reference Example 7, had an ammonia storage capacity of 1.9 mmol / g. The ammonia storage capacity was determined as defined in Reference Example 1. The ammonia storage capacity of the catalyst of Comparative Example 1 is higher in the downstream region than in the upstream region. This example is representative of prior art US9597636B2, which discloses that the ammonia storage capacity should be higher in the downstream portion of the catalyst.

[0280] Example 5: Testing of the catalyst of Example 4 and the catalyst of Comparative Example 1 - NOx emissions Lamp (C NOx =C NO (Feed) = 750 ppm, NSR (normal stoichiometric ratio) of ammonia to NOx = 1.2, space velocity of 80,000 h at 3-inch overall length -1 , C O2-供給 =10% by mass, C H2O-供給 =5% by mass, C CO2-供給A selective catalytic reduction (SCR) steady-state treatment was performed using urea (5% by mass). The inlet temperature of the tested catalyst was varied over time (T = 180°C to 450°C - Figure 3 / T = 250°C to 450°C - Figure 4) during and after urea injection was stopped, and NOx concentrations were measured. The experiment was conducted in a laboratory reactor. This test was intended to simulate a rapid temperature change without adding ammonia to the feed. Therefore, the NH3 feed was stopped simultaneously with the temperature increase. This required the catalyst to operate using stored NH3 at the time the ammonia feed was stopped, allowing for investigation of the catalyst's dynamic behavior. This test must mimic typical engine acceleration conditions, where the ammonia (in this case, urea) feed cannot adapt quickly enough to the engine's exhaust gas composition and temperature transitions. The results are shown in Figures 3 and 4.

[0281] As can be seen from FIG. 3, from t = 4000 to 4121 seconds (inlet temperature 180°C), the NOx conversion rate of the catalyst of Example 4 is approximately 16%, while the NOx conversion rate of the catalyst of Comparative Example 1 is low, at approximately 12%. Furthermore, when NH3 injection was stopped at t = 4121 seconds and the temperature was increased, the NOx conversion rates of the two catalysts rapidly increased to approximately 93% from t = 4121 to 4150 seconds. However, from t = approximately 4160 to 4400 seconds, the NOx conversion rate of the catalyst of Comparative Example 1 decreased. In contrast, the NOx conversion rate of the catalyst of the present invention (Example 4) continued to increase from t = 4150 to 4200 seconds, reaching approximately 99%. Thereafter, at t = 4200 seconds, the NOx conversion rate of the catalyst of the present invention began to decrease, but was still superior to the NOx conversion rate of the catalyst of Comparative Example 1.

[0282] As can be seen from FIG. 4, from t = 13,500 to 13,821 seconds (inlet temperature 250°C), the NOx conversion rate of the catalyst of Example 4 is approximately 91%, while the NOx conversion rate of the catalyst of Comparative Example 1 is low, approximately 85%. Furthermore, when NH3 injection was stopped and the temperature was increased at t = 13,821 seconds, the NOx conversion rates of both catalysts increased from t = 13,821 to 13,850 seconds, but the NOx conversion rate of the catalyst of Example 4 was still superior to that of the catalyst of Comparative Example 1. However, from t = approximately 1,360 to 14,000 seconds, the NOx conversion rate of the catalyst of Comparative Example 1 decreased. In contrast, for the catalyst of the present invention (Example 4), the NOx conversion rate of the catalyst of Example 4 was 100% at t = 13,850 seconds and remained at 100 to approximately 98% until t = approximately 13,890 seconds. Thereafter, at about t=13890 seconds, the NOx conversion of the catalyst of the present invention began to decline, but was still superior to the NOx conversion of the catalyst of Comparative Example 1.

[0283] 3 and 4 show that the catalyst according to the present invention allows a high NOx conversion rate to be maintained for a longer period of time compared to the comparative catalyst, which is further noted to be due to the higher ammonia storage capacity of the upstream portion of the catalyst according to the present invention compared to the ammonia storage capacity of the downstream portion.

[0284] Reference Example 8: Preparation of SCR catalyst (containing Cu-CHA) The catalyst of Reference Example 8 was prepared in the same manner as the catalyst of Reference Example 7, except that a different substrate was used. Specifically, an uncoated honeycomb flow-through monolith cordierite substrate (diameter: 1 inch x length: 6 inches (two 3-inch long substrates placed side by side with no gap between the substrates), cylindrical with 600 cells per square inch and a wall thickness of 3 mils) was used. The final coating loading on the catalyst after calcination was approximately 2.75 g / in. 3 and Cu-CHA was 2.62 g / in 3 , ZrO2 0.13g / in 3 The ammonia storage capacity of the coating measured in accordance with Reference Example 1 was 1.9 mmol / g.

[0285] Example 6: SCR catalyst consisting of the catalyst of Example 1b) and the catalyst of Reference Example 8 The catalyst of Example 1b) and the catalyst of Reference Example 8 were combined so that the catalyst of Example 1b) was upstream of the catalyst of Reference Example 8 and the catalyst of Reference Example 8 was downstream of the catalyst of Example 1b) with no gap between the two catalysts to prepare an SCR catalyst. The length of the prepared catalyst was 8 inches (2 inches - Example 1b) and 6 inches - Reference Example 8).

[0286] As a result, the upstream portion of the catalyst of Example 6, which used the catalyst of Example 1b), had an ammonia storage amount of 2.8 to 3.0 mmol / g, and the downstream portion of the catalyst of Example 4, which used the catalyst of Reference Example 8, had an ammonia storage amount of 1.9 mmol / g. The ammonia storage amount was determined as defined in Reference Example 1. The ammonia storage amount in the upstream region of the catalyst of Example 6 was higher than the ammonia storage amount in the downstream region of the catalyst.

[0287] Comparative Example 2: SCR catalyst consisting of the catalyst of Reference Example 6 and the catalyst of Reference Example 8 The catalysts of Reference Example 6 and Reference Example 8 were combined to prepare an SCR catalyst, with the catalyst of Reference Example 6 located upstream of the catalyst of Reference Example 8, the catalyst of Reference Example 7 located downstream of the catalyst of Reference Example 8, and no gap between the two catalysts. The length of the prepared catalyst was 8 inches (2 inches for Reference Example 6 and 6 inches for Reference Example 8).

[0288] As a result, the upstream portion of the catalyst of Comparative Example 1, which used the catalyst of Reference Example 6, had an ammonia storage capacity of 1.2 mmol / g, and the downstream portion of the catalyst of Comparative Example 1, which used the catalyst of Reference Example 8, had an ammonia storage capacity of 1.9 mmol / g. The ammonia storage capacity was determined as defined in Reference Example 1. The ammonia storage capacity in the downstream region of the catalyst of Comparative Example 2 was higher than that in the upstream region of the catalyst. This example is representative of prior art US9597636B2, which discloses the need for higher ammonia storage capacity in the downstream portion of the catalyst.

[0289] Example 7: Testing of the catalysts of Example 6 and Comparative Example 2 - NOx emissions Lamp (C NOx =C NO (Feed) = 750 ppm, NSR (Normalized Stoichiometric Ratio) of ammonia to NOx = 1.2, Space Velocity 30,000 h at 8-inch overall length -1 , C O2-供給 =10% by mass, C H2O-供給 =5% by mass, C CO2-供給 A selective catalytic reduction (SCR) steady-state process was performed with urea (U / C) = 5% by mass. NOx concentrations were measured over time during and after urea injection, varying the inlet temperature of the tested catalyst (T = 180°C to 450°C - Figure 4). This test was intended to simulate a rapid temperature change without adding ammonia to the feed. Therefore, the NH3 feed was also stopped simultaneously with the temperature increase. This required the catalyst to operate using stored NH3 at the time the ammonia feed was stopped, allowing for investigation of the catalyst's dynamic behavior. This test must mimic typical engine acceleration conditions, where the ammonia (in this case, urea) feed cannot adapt quickly enough to the changing engine exhaust composition and temperature. The results are shown in Figure 5.

[0290] As can be seen from FIG. 5, from t=4000 to 4122 seconds (inlet temperature 180°C), the NOx conversion of the catalyst of Example 6 is approximately 56%, while the NOx conversion of the catalyst of Comparative Example 2 is lower, i.e., approximately 43%. Furthermore, when NH3 injection was stopped at t=4122 seconds and the temperature was increased, the NOx conversion of both catalysts increased sharply to approximately 100% from t=4122 to 4170 seconds. However, from t=approximately 4300 to 4350 seconds, the NOx conversion of these two catalysts decreased. However, the NOx conversion of the catalyst of the present invention (Example 6) decreased more slowly than that of the catalyst of Comparative Example 2, and therefore remained high from t=4350 to 4550 seconds.

[0291] 5 shows that the catalyst according to the present invention allows a high NOx conversion rate to be maintained for a longer period of time compared to the comparative catalyst, which is further noted to be due to the higher ammonia storage capacity of the upstream portion of the catalyst according to the present invention compared to the ammonia storage capacity of the downstream portion.

[0292] References US9352307B2 EP2520365A2 US9597636B2

Claims

1. A catalyst for selective catalytic reduction of nitrogen oxides, the catalyst comprising: (i) a substrate having 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 interior wall of the flow-through substrate extending therethrough; (ii) a 12-ring pore zeolite material comprising a first metal, the first metal being one or more of copper and iron, and the 12-ring pore zeolite material is selected from the group consisting of CuO and Fe ２ O ３ a first coating comprising a first metal in an amount of z1 wt.%, calculated by dividing the mass of the first metal by the mass of the 12-ring small pore zeolite material comprising the first metal; (iii) an 8-ring pore zeolite material containing a second metal, the second metal being one or more of copper and iron, and the 8-ring pore zeolite material is ２ O ３ A second coating comprising a second metal in an amount of z2% by weight, calculated by dividing the mass of the second metal by the mass of the 8-ring pore zeolite material comprising the second metal. Equipped with wherein the first coating is disposed on a surface of an inner wall of the substrate, the surface defining an interface between the inner wall and the passageway, and extends over x % of the axial length of the substrate from the inlet end toward the outlet end of the substrate, where x is in the range of 10 to 75; the second coating extends over y % of the axial length of the substrate from the outlet end toward the inlet end of the substrate, where y is in the range of 25 to 90; the ratio z1:z2 is in the range of 0.5:1 to 0.95:1; the first coating further comprises a 10-ring pore zeolite material comprising a third metal, the third metal being one or more of copper and iron; Catalyst, wherein said first coating (ii) has an ammonia storage capacity A1(NH3) of at least 2.1 mmol / g and said second coating (iii) has an ammonia storage capacity A2(NH3) of less than 2 mmol / g, their ammonia storage capacities being determined as defined in Reference Example 1.

2. 2. The catalyst of claim 1, wherein y is 100-x.

3. 3. The catalyst of claim 1 or 2, wherein the 12-ring pore zeolite material contained in the first coating is selected from the group consisting of BEA, FAU, USY, GME, MOR, OFF, mixtures of two or more thereof, and mixed types of two or more thereof.

4. The 12-ring pore zeolite material included in the first coating includes a first metal that is iron, and the 12-ring pore zeolite material is ２ O ３ 4. The catalyst of claim 1, wherein the catalyst comprises iron in an amount z1 wt. % calculated by dividing the mass of the first metal calculated as: mass of the first metal divided by the mass of the 12-ring pore zeolitic material comprising the first metal, wherein z1 is in the range of 1.0 to 10.

5. 5. The catalyst of any one of claims 1 to 4, wherein the first coating further comprises a 10-ring pore zeolite material containing a third metal which is iron.

6. The first coating (ii) has an ammonia storage capacity A1 in the range of 2.2 to 10.0 mmol / g （ＮＨ３） The catalyst according to any one of claims 1 to 5, wherein the ammonia storage capacity is determined as defined in Reference Example 1.

7. 7. The catalyst according to claim 1, wherein the 8-ring pore zeolite material contained in the second coating is selected from the group consisting of CHA, AEI, RTH, LEV, DDR, KFI, ERI, AFX, a mixture of two or more thereof, and a mixed type of two or more thereof.

8. The second coating (iii) has an ammonia storage capacity A2 in the range of 0.5 to 1.99 mmol / g. （ＮＨ３） The catalyst according to any one of claims 1 to 7, wherein the ammonia storage capacity is determined as defined in Reference Example 1.

9. A method for producing the catalyst for selective catalytic reduction of nitrogen oxides according to any one of claims 1 to 8, comprising the steps of: (1) providing a substrate having 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 interior wall of the flow-through substrate extending therethrough; (2) preparing a first mixture comprising water and a 12-ring pore zeolite material containing a first metal, the first metal being one or more of copper and iron, wherein the 12-ring pore zeolite material is CuO and Fe ２ O ３ The mass of the first metal calculated as follows is divided by the mass of the 12-ring small pore zeolite material containing the first metal, and the mass of the first metal is 1 mass%; adding to the resulting first mixture a 10-ring small pore zeolite material containing a third metal, the third metal being one or more of copper and iron; (3) disposing the first mixture obtained in (2) on the inner wall surface of the substrate prepared in (1) over x% of the axial length of the substrate from the inlet end toward the outlet end of the substrate, where x is in the range of 10 to 75; (4) drying the mixture-treated substrate obtained in (3) to obtain a substrate having a first coating disposed thereon; and, optionally, baking; (5) preparing a second mixture comprising water and an 8-ring pore zeolite material containing a second metal, the second metal being one or more of copper and iron, wherein the 8-ring pore zeolite material is a mixture of CuO and Fe ２ O ３ The mass of the second metal is calculated by dividing the mass of the second metal by the mass of the 8-membered ring pore zeolite material containing the second metal, and the mass of the second metal is calculated by dividing the mass of the 8-membered ring pore zeolite material containing the second metal by 2% by mass, (6) disposing the second mixture from (5) on the substrate from (4) having the first coating disposed thereon, over y% of the axial length of the substrate from the outlet end toward the inlet end of the substrate, where y is in the range of 25 to 90; (7) drying the mixture-treated substrate obtained in (6) to obtain a substrate having the first coating and the second coating disposed thereon; (8) The substrate having the first coating and the second coating disposed thereon obtained in (7) is calcined to obtain a catalyst. Including, wherein the ratio z1:z2 is in the range of 0.5:1 to 0.95:

1.

10. (2) furthermore, (2.1) Preparing a 12-ring pore zeolite material; (2.2) mixing a source of a first metal with the 12-ring pore zeolite material obtained in (2.1); (2.3) Calcining the mixture obtained in (2.2) to obtain a 12-ring pore zeolite material containing a first metal; (2.4) Mixing water with the 12-ring pore zeolite material containing the first metal. Including, (2) further states: (2.5) adding a 10-ring pore zeolite material containing a third metal to the mixture obtained in (2.4); 10. The method of claim 9, comprising:

11. An exhaust gas treatment system for treating exhaust gas emitted from a combustion engine, the system comprising one or more catalysts for selective catalytic reduction of nitrogen oxides according to any one of claims 1 to 8, and one or more of a diesel oxidation catalyst, a catalyzed soot filter, and an ammonia oxidation catalyst.

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