Mn-perovskite catalyst for the treatment of an exhaust gas stream containing one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons

Abstract

The present invention relates to a catalyst for the treatment of an exhaust gas stream containing one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons, the catalyst comprising a first washcoat layer comprising a perovskite, wherein the perovskite contains Mn, and a substrate, wherein the substrate has an inlet end through which the exhaust gas stream may enter the catalyst, and an outlet end through which the exhaust gas stream may exit the catalyst, wherein the catalyst further comprises one or more platinum group metals comprising Pt, Pd, or Pt and Pd, wherein the one or more platinum group metals are at least in part contained in one or more of: (a) the first washcoat layer, and (b) an optional second washcoat layer, or (c) optional second and third washcoat layers. Further, the present invention particularly relates to an exhaust gas treatment system comprising an internal combustion engine and an exhaust gas conduit for exhaust gas from the internal combustion engine, wherein the exhaust gas conduit comprises one or more of said catalysts.

Description

[0001] Mn-Perovskite Catalyst for the treatment of an exhaust gas stream containing one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons

[0002] TECHNICAL FIELD

[0003] The present invention relates to a catalyst for the treatment of an exhaust gas stream containing one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons, an exhaust gas treatment system comprising said catalyst, a method for the treatment of an exhaust gas stream containing one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons using said catalyst, and use of said catalyst for the oxidation of one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons.

[0004] INTRODUCTION

[0005] The present invention relates to the use of a diesel oxidation catalyst (DOC) with enhanced oxidation function, in particular with enhanced oxidation function of one or more of formaldehyde (HCHO), nitrogen oxide (NO), and hydrocarbons (including diesel fuel). It is known that formaldehyde is a toxic material that is coming under increasing regulation within indoor air spaces due to its release from various building materials used in the construction industry. Tighter regulations are also being implemented for formaldehyde emissions from the engine exhaust of passenger and delivery vehicles. Generally, manganese oxides (e.g., MnO2) are known to be active for destroying formaldehyde under ambient conditions, but they do not have the required thermal stability to survive in a typical engine exhaust environment. In particular, phase transitions at high temperature (e.g., higher than 400 °C) cause the structure of MnC>2 to collapse such that the surface area and pore volume are so low as to be catalytically ineffective. One way to improve the stability of the Mn oxide at high temperature (as well as other catalytically useful base metal oxides such as copper, ceria and iron) can be to support them on refractory oxide materials which themselves have high stability when exposed to high temperatures in the engine exhaust. Materials such as aluminum oxide (AI2O3) and zirconium oxide (ZrO2) can be useful in this regard.

[0006] The key challenge for inclusion of Mn-containing base metal oxide (BMO) catalysts in technology for abatement of exhaust emissions from diesel vehicles can be seen in the intrinsically poor sulfur resistance of manganese reflected in the high desulfation temperature of manganese sulfate. As described in the literature, significant desulfation of MnSC does not occur at temperatures typical for filter regeneration or de-sulfation (de-SOx) on a diesel engine (about 650-700 °C). In flowing nitrogen, 800 °C is typically required, while in flowing air, the temperature is even about 30 °C higher (Figure 1). It is known that Pt and Pd supported on a high temperature resistant refractory metal oxide support provides efficient oxidation of CO and HC pollutants emitted from diesel engines. Such DOC compositions are needed by vehicle manufacturers to meet ever more stringent worldwide CO and HC exhaust emission requirements. An additional function of the DOC composition when placed in the exhaust of a diesel vehicle is to oxidize diesel fuel injected into the exhaust upstream of the DOC in order to create a high temperature exotherm that is used to thermally oxidize soot that has accumulated on a diesel particulate filter (DPF) or a catalyzed soot filter (CSF) located downstream of the DOC composition. Alternatively, the hydrocarbon concentration in the exhaust stream can be increased for exotherm generation by adjusting the combustion process through various post-injection methods or the like. Temperatures greater 600 °C at the DPF or CSF inlet are preferred to provide efficient oxidation of the retained soot. The concentration of diesel fuel injected into the exhaust stream needed to provide the desired exotherm is quite high, approximately 1 % (10,000 ppm) on a C1 basis or more. The temperature at which the DOC composition can oxidize (“light-off’) the injected fuel needs to be as low as possible, preferably less than 300 °C. In addition, the amount of hydrocarbon slip bypassing the DOC catalyst during exotherm generation needs to be as low as possible, preferably less than 3,000 ppm, 2,000 ppm or even 1 ,000 ppm.

[0007] WO 2022 / 047132 A1 relates to an oxidation catalyst composition for catalytic articles, exhaust gas treatment systems for reducing formaldehyde levels in engine exhaust emissions. In particular, an oxidation catalyst is disclosed in claim 1 comprising a platinum group metal (PGM) component comprising Pd, Pt, or a combination thereof, a manganese component, and a first refractory metal oxide support material comprising zirconia.

[0008] US 10,598,061 B2 relates to methods and systems for a diesel oxidation catalyst. In particular, a method is disclosed in claim 1 comprising: generating NO2 in a catalyst comprising a washcoat with zirconium, one or more base metal oxides, and a palladium oxide, with an exhaust gas flow rate being between lower and upper threshold flow rates; and facilitating a regeneration of a particulate filter located downstream of the catalyst via NO2 when an exhaust gas temperature is greater than a threshold temperature where the palladium oxide is contained in an upstream portion of the catalyst relative to a direction of exhaust gas flow; and the one or more base metal oxides are contained in a downstream portion of the catalyst relative to the direction of exhaust gas flow.

[0009] US 10,392,980 B2 relates to methods and systems for a diesel oxidation catalyst. In particular, a method is disclosed in claim 1 comprising: passing diesel combustion exhaust gas over a diesel oxidation catalyst having a washcoat comprising zirconium oxide, palladium oxide, and at least one base metal oxide, the washcoat coated on a surface of a substrate with the at least one base metal oxide coated to a downstream portion of the substrate in a greater amount than coated to an upstream portion and the palladium oxide coated to the upstream portion of the substrate in a greater amount than coated to the downstream portion, downstream referring to an axial direction of exhaust gas flow, and where the palladium oxide is 0.5-3 weight percent of the washcoat. US 2018 / 333677 A1 relates to catalyst articles coated with a multi-layer catalyst composition, emission treatment systems comprising such a catalyst article, and methods of use and manufacture thereof. In particular, a catalyst article is defined in claim 1 , the catalyst article comprising a multi-layer catalyst composition adapted for oxidation of gaseous HC and CO emissions and conversion of NOx to N2, the catalyst article comprising: a substrate in adherence to a multi-layer catalyst composition; the multi-layer catalyst composition comprising a first layer, a second layer and optionally an intermediate layer between the first and second layers; the first layer positioned between the substrate and the second layer and comprising a first porous refractory oxide material impregnated with at least one base metal component; the second layer comprising a second porous refractory oxide material impregnated with at least one platinum group metal; and the intermediate layer comprising a refractory oxide material, wherein the second layer is substantially free of alumina and / or the intermediate layer is present and is substantially free of alumina.

[0010] US 2018 / 318805 A1 relates to a diesel oxidation catalyst composition, catalyst articles coated with such a composition, emission treatment systems comprising such a catalyst article, and methods of use thereof. In particular, a diesel oxidation catalyst composition is defined in claim 1 , the composition comprising at least one platinum group metal impregnated onto a porous refractory oxide material in particulate form and at least one base metal oxide impregnated onto a porous refractory oxide material in particulate form, wherein the porous refractory oxide material impregnated with at least one platinum group metal and the porous refractory oxide material impregnated with at least one base metal oxide are in the form of a mixture or wherein the at least one platinum group metal and the at least one base metal oxide are impregnated on the same porous refractory oxide material.

[0011] M. C. Alvarez-Galvan et al. disclose in Applied Catalysis B. 2004, 51 , 83-91 alumina-supported manganese catalysts with manganese loadings ranging from 3.9 to 18.2 wt.%. Said catalysts were prepared and tested in the combustion of formaldehyde / methanol mixture in an air stream.

[0012] US 2010 / 229533 A1 relates to a perowskite-type compounds for use in lean NOx traps. In the Example, a catalyst material is described particularly comprising CeO2-ZrO2 as carrier loaded with Lao.gSro.-iMnOs as NOx oxidation catalyst, BaO as NOx storage catalyst, Rh as NOx reduction catalyst, and Pd.

[0013] US 2017 / 095803 A1 relates to an effect of type of support oxide on sulfur resistance of syner- gized PGM as diesel oxidation catalyst. According to claim 1 of said document, a catalyst system particularly comprises a substrate, a washcoat including YMnOs perovskite and a doped ZrO2 support oxide, and an overcoat including a platinum group metal catalyst and a support oxide selected from the group consisting of Si-doped alumina, cerium-zirconia, and La-doped alumina, wherein the washcoat is free of platinum group metal catalyst. US 2010 / 086458 A1 relates to a method and architecture for oxidizing nitric oxide in exhaust gas from hydrocarbon fuel source with a fuel lean combustion mixture. According to claim 1 of said document, a catalytic oxidation reactor for oxidizing the nitric oxide component of an exhaust stream from a hydrocarbon fueled power source operated with a fuel lean combustion mixture particularly comprises a substrate material and a perovskite catalyst of general formula ABO3 coupled to a portion of said substrate material, wherein A comprises a rare earth metal from the Lanthanide series and / or an alkaline-earth metal and wherein B comprises a transition metal.

[0014] US 2018 / 318805 A1 relates to a diesel oxidation catalyst combining platinum group metal with base metal oxide. According to claim 1 of said document, a diesel oxidation catalyst composition particularly comprises at least one platinum group metal impregnated onto a porous refractory oxide material in particulate form and at least one base metal oxide impregnated onto a porous refractory oxide material in particulate form, wherein the porous refractory oxide material impregnated with at least one platinum group metal and the porous refractory oxide material impregnated with at least one base metal oxide are in the form of a mixture or wherein the at least one platinum group metal and the at least one base metal oxide are impregnated on the same porous refractory oxide material.

[0015] US 2023 / 321636 A1 relates to an oxidation catalyst comprising a platinum group metal and a base metal or metalloid oxide. In particular, oxidation catalyst compositions are disclosed in said document particularly comprising a platinum group metal (PGM) component comprising palladium, platinum, or a combination thereof; a first oxide chosen from oxides of cerium, silicon, iron, cobalt, zinc, chromium, molybdenum, nickel, tungsten, magnesium, antimony, tin, lead, yttrium, and combinations thereof; and a first refractory metal oxide support material; catalytic articles; and exhaust gas treatment systems, as well as methods of making and using such oxidation catalyst compositions.

[0016] Therefore, it was an object of the present invention to provide a catalyst having an improved performance with respect to the conversion of one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons, in particular after being exposed to a sulfation and de-sulfation treatment.

[0017] DETAILED DESCRIPTION

[0018] It has surprisingly been found that an improved catalyst can be provided for the conversion of one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons in an exhaust gas. In particular, it has been surprisingly found that a catalyst can be provided showing an improved performance with respect to the conversion of one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons after being exposed to a sulfation and de-sulfation treatment as encountered in a typical application. Furthermore, it has been surprisingly found that the catalyst according to the present invention shows enhanced hydrocarbon (HO) and nitrogen oxide (NO) oxidation function. In particular, it has surprisingly been found that the benefit of using BMO-containing catalyst to reduce platinum group metal in diesel exhaust treatment systems is not limited only to HCHO oxidation, but also to hydrocarbon and NO oxidation. This enables vehicle manufacturers to meet ever tightening vehicle emissions standards while also reducing overall PGM usage and costs. It has also been surprisingly found that use of a diesel oxidation catalyst (DOC) comprising both a platinum group metal (PGM) and a base metal oxide (BMO) catalyst leads to a catalyst having enhanced fuel burning function. Furthermore, it can be expected that the catalyst of the present invention is able to oxidize soot accumulation on a substrate, in particular on a wall-flow substrate, especially since the Mn-containing washcoat layer can generate NO2 which oxidizes soot. Additionally, the catalyst of the present invention can enable a comparatively lower N2O production, in particular due to its comparatively lower content of platinum group metals.

[0019] Therefore, the present invention relates to a catalyst for the treatment of an exhaust gas stream containing one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons, the catalyst comprising a first washcoat layer comprising a perovskite, wherein the perovskite contains Mn , and a substrate, wherein the substrate has an inlet end through which the exhaust gas stream may enter the catalyst, and an outlet end through which the exhaust gas stream may exit the catalyst, wherein the catalyst further comprises one or more platinum group metals comprising Pt, Pd, or Pt and Pd, wherein the one or more platinum group metals are at least in part contained in one or more of:

[0020] (a) the first washcoat layer, and

[0021] (b) an optional second washcoat layer, or

[0022] (c) optional second and third washcoat layers.

[0023] It is preferred that the optional second washcoat layer is substantially free of a Mn-containing perovskite, wherein more preferably the optional second washcoat layer is free of a Mn-contain- ing perovskite, wherein the optional second washcoat layer is more preferably substantially free of Mn, wherein the optional second washcoat layer is more preferably free of Mn.

[0024] Within the meaning of the present invention, a washcoat layer is substantially free of an element or compound(s) when the washcoat layer contains said element or compound(s) in an amount of 1 wt.-% or less calculated as the element or compound(s) and based on 100 wt.-% of the wash-coat layer, preferably in an amount of 0.5 wt.-% or less, more preferably of 0.1 wt.-% or less, more preferably of 0.05 wt.-% or less, more preferably of 0.01 wt.-% or less, more preferably of 0.005 wt.-% or less, more preferably of 0.001 wt.-% or less. It is preferred that the content of the Mn-containing perovskite in the first washcoat layer is in the range of from 10 to 99 wt.-% based on 100 wt.-% of the first washcoat layer, more preferably from 20 to 95 wt.-%, more preferably from 30 to 75 wt.-%, more preferably from 40 to 60 wt.- %, more preferably from 45 to 50 wt.-%.

[0025] It is preferred that the Mn-containing perovskite has the formula

[0026] (AyBl.y)l.xMnO3-z (I) wherein A is a transition metal and B is an alkaline earth metal, wherein y is in the range of from 0 to 1 , wherein x is in the range of from 0 to 0.10, and wherein z is in the range of from 0 to 0.5.

[0027] In the case wherein the Mn-containing perovskite has the formula (I) as defined herein, it is preferred that y is in the range of from greater than 0 to 0.95, more preferably of from 0.05 to 0.9, more preferably of from 0.1 to 0.8, more preferably of from 0.2 to 0.6, more preferably of from 0.3 to 0.5, more preferably of from 0.35 to 0.45, more preferably of from 0.38 to 0.42, wherein y more preferably is 0.40.

[0028] Further in the case wherein the Mn-containing perovskite has the formula (I) as defined herein, it is preferred that x is in the range of from 0.01 to 0.09, more preferably of from 0.02 to 0.08, more preferably of from 0.03 to 0.07, more preferably of from 0.04 to 0.06, wherein x more preferably is 0.05.

[0029] Further in the case wherein the Mn-containing perovskite has the formula (I) as defined herein, it is preferred that z is in the range of from greater than 0 to 0.5, more preferably of from 0.1 to 0.4, more preferably of from 0.2 to 0.3.

[0030] Further in the case wherein the Mn-containing perovskite has the formula (I) as defined herein, it is preferred that transition metal A is selected from the group consisting of Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and combinations of two or more thereof, more preferably from the group consisting of Y, La, Ce, Pr, Nd, Pm, Sm, and combinations of two or more thereof, more preferably from the group consisting of La, Ce, Pr, Nd, and combinations of two or more thereof, wherein more preferably A is La and / or Ce, wherein more preferably A is La.

[0031] Further in the case wherein the Mn-containing perovskite has the formula (I) as defined herein, it is preferred that the alkaline earth metal B is selected from the group consisting of Mg, Ca, Sr, Ba, and combinations of two or more thereof, more preferably from the group consisting of Ca, Sr, Ba, and combinations of two or more thereof, wherein more preferably B is Sr and / or Ca, wherein more preferably B is Sr.

[0032] It is preferred that the first washcoat layer further comprises a particulate metal oxide, wherein the particulate metal oxide is preferably substantially free of Mn, and wherein the particulate metal oxide is more preferably selected from the group consisting of ZrC>2, AI2O3, SiC>2, TiC>2, La2C>3-doped ZrC>2, CeO2-ZrO2 mixed oxide, La2C>3-doped CeO2-ZrO2 mixed oxide, Nd2Os-doped CeO2-ZrC>2 mixed oxide, Y2Os-doped CeO2-ZrO2 mixed oxide, praseodymium oxide-doped CeO2-ZrC>2 mixed oxide, ZrC>2-doped AI2O3, ZrC>2-doped SiC>2, SiC>2-doped AI2O3, CUO-AI2O3 mixed oxide, and mixtures of two or more thereof, more preferably from the group consisting of ZrC>2, La2C>3-doped ZrC>2, CeO2-ZrO2 mixed oxide, La2C>3-doped CeO2-ZrO2 mixed oxide, Nd20s- doped CeO2-ZrC>2 mixed oxide, Y2Os-doped CeO2-ZrO2 mixed oxide, P^Os-doped CeO2-ZrO2 mixed oxide, P^On-doped CeO2-ZrO2 mixed oxide, PrC>2-doped CeO2-ZrO2 mixed oxide, ZrC>2- doped AI2O3, ZrC>2-doped SiC>2, and mixtures of two or more thereof, more preferably from the group consisting of ZrC>2, La2C>3-doped ZrC>2, CeO2-ZrO2 mixed oxide, La2C>3-doped CeO2-ZrO2 mixed oxide, Nd2Os-doped CeO2-ZrO2 mixed oxide, Y2Os-doped CeO2-ZrO2 mixed oxide, P^Os- doped CeO2-ZrC>2 mixed oxide, P^On-doped CeO2-ZrO2 mixed oxide, and mixtures of two or more thereof, wherein more preferably the particulate metal oxide is La2C>3-doped ZrC>2, wherein more preferably the particulate metal oxide is ZrO2doped with La20s in an amount ranging from 1 to 50 wt.% calculated as La20s and based on 100 wt.-% of ZrO2and La20s, preferably from 3 to 30 wt.-%, more preferably from 5 to 15 wt.-%, more preferably from 8 to 10 wt.-%.

[0033] In the case wherein the first washcoat layer further comprises a particulate metal oxide as defined herein, it is preferred that the particulate metal oxide has a BET surface area in the range of from 10 to 300 m2 / g, more preferably of from 30 to 200 m2 / g, more preferably of from 50 to 150 m2 / g, more preferably of from 60 to 100 m2 / g, more preferably of from 70 to 80 m2 / g.

[0034] Further in the case wherein the first washcoat layer further comprises a particulate metal oxide as defined herein, it is preferred that in first washcoat layer the weight ratio of the Mn-containing perovskite to the particulate metal oxide is in the range of from 5:95 to 95:5, more preferably of from 10:90 to 90:10, more preferably of from 20:80 to 80:20, more preferably of from 30:70 to 70:30, more preferably of from 40:60 to 60:40, more preferably of from 45:55 to 55:45.

[0035] It is preferred that the first washcoat layer is substantially free of Ce, wherein more preferably the first washcoat layer is free of Ce.

[0036] In the case wherein the first washcoat layer is substantially free of Ce, it is preferred that the catalyst is substantially free of Ce, wherein more preferably the catalyst is free of Ce. Within the meaning of the present invention, the catalyst is substantially free of an element or compound(s) when the catalyst contains said element or compound(s) in an amount of 1 wt.-% or less calculated as the element or compound(s) and based on 100 wt.-% of the catalyst, preferably in an amount of 0.5 wt.-% or less, more preferably of 0.1 wt.-% or less, more preferably of 0.05 wt.-% or less, more preferably of 0.01 wt.-% or less, more preferably of 0.005 wt.-% or less, more preferably of 0.001 wt.-% or less.

[0037] It is preferred that the substrate is a wall-flow substrate or a flow-through substrate, more preferably a honeycomb wall-flow substrate or a honeycomb flow-through substrate, more preferably a honeycomb flow-through substrate, wherein the flow-through substrate is more preferably a flow-through substrate with high porosity walls.

[0038] It is preferred that the loading of the first washcoat layer is in the range of from 0.5 to 5 g / in3, more preferably of from 1 to 3 g / in3, more preferably of from 1.5 to 2.5 g / in3, more preferably of from 1 .8 to 2 g / in3.

[0039] Within the meaning of the present invention, the loading of a washcoat layer in the catalyst refers to the loading of said washcoat layer based on the volume of the catalyst in which said washcoat layer is contained. Accordingly, within the meaning of the present invention, the loading of a washcoat layer only contained in a certain portion or zone of the catalyst is based on the volume of that portion or zone of the catalyst. Thus, by means of examples, if a washcoat layer is provided over 50% of the axial length of a honeycomb substrate, its loading is calculated based on 50% of the total volume of the honeycomb substrate.

[0040] It is preferred that the loading of the second washcoat layer is in the range of from 0.25 to 6 g / in3, more preferably of from 0.5 to 6 g / in3, more preferably of from 1 to 5 g / in3, more preferably of from 1 .5 to 4.5 g / in3, more preferably of from 2 to 4 g / in3, more preferably of from 2.2 to 3.5 g / in3, more preferably of from 2.5 to 3.2 g / in3, more preferably of from 2.8 to 3.0 g / in3.

[0041] It is preferred that the catalyst comprises one or more platinum group metals consisting of Pt, Pd, or Pt and Pd, wherein more preferably the catalyst comprises Pt, or Pt and Pd as the one or more platinum group metals, wherein more preferably the catalyst comprises Pt and Pd as the one or more platinum group metals.

[0042] It is preferred that the catalyst comprises Pt, calculated as the element, at a loading in the range of from 2 to 250 g / ft3, more preferably of from 5 to 150 g / ft3, more preferably of from 10 to 125 g / ft3, more preferably of from 20 to 100 g / ft3, more preferably of from 25 to 85 g / ft3, more preferably of from 30 to 80 g / ft3, more preferably of from 40 to 60 g / ft3. Within the meaning of the present invention, the loading of Pt, Pd, or Pt and Pd in the catalyst refers to the loading of Pt, Pd, or Pt and Pd based on the volume of the catalyst in which Pt, Pd, or Pt and Pd is contained. In the event that Pt, Pd, or Pt and Pd is contained in one or more zones of the catalyst, it is preferred within the meaning of the present invention, that the loading of Pt, Pd, or Pt and Pd is based on the volume of the catalyst in which the one or more Pt, Pd, or Pt and Pd zones are contained. Thus, by means of examples, if Pt, Pd, or Pt and Pd is provided in a zone extending over 50% of the axial length of a honeycomb substrate, its loading is calculated based on 50% of the total volume of the honeycomb substrate.

[0043] It is preferred that the catalyst comprises Pd, calculated as the element, at a loading in the range of from 1 to 80 g / ft3, more preferably of from 5 to 60 g / ft3, more preferably of from 10 to 50 g / ft3, more preferably of from 15 to 40 g / ft3, more preferably of from 20 to 30 g / ft3.

[0044] It is preferred that the catalyst comprises Pt and Pd, calculated as the respective element, at a total Pt and Pd loading in the range of from 2 to 250 g / ft3, more preferably of from 5 to 200 g / ft3, more preferably of from 10 to 150 g / ft3, more preferably of from 20 to 130 g / ft3, more preferably of from 30 to 125 g / ft3, more preferably of from 40 to 110 g / ft3, more preferably of from 50 to 100 g / ft3, more preferably of from 60 to 90 g / ft3, more preferably of from 70 to 80 g / ft3.

[0045] It is preferred that the catalyst comprises Pt and Pd at a Pt : Pd weight ratio in the range of from 30:70 to 90:10, more preferably of from 50:50 to 80:20, more preferably of from 60:40 to 75:25, more preferably of from 65:35 to 70:30.

[0046] It is preferred that at least part of the one or more platinum group metals are supported on a particulate support material, wherein the particulate support material is more preferably selected from the group consisting of AI2O3, SiC>2, TiC>2, SiCh-doped AI2O3, Mn oxide-doped AI2O3, and mixtures of two or more thereof, wherein preferably the one or more platinum group metals are supported on AI2O3 and / or SiC>2-doped AI2O3 and / or Mn oxide-doped AI2O3, more preferably SiC>2-doped AI2O3 or AI2O3 or Mn oxide-doped AI2O3, more preferably SiC>2-doped AI2O3 or AI2O3, wherein more preferably at least part of the one or more platinum group metals are supported on SiC>2-doped AI2O3.

[0047] In the case wherein at least part of the one or more platinum group metals are supported on a particulate support material as defined herein, it is preferred according to a first alternative that the Mn oxide-doped AI2O3 comprises from 1 to 10 weight-%, more preferably from 4 to 6 weight- %, of Mn oxide, calculated as MnC>2, based on 100 weight-% of the Mn oxide-doped AI2O3.

[0048] Further in the case wherein at least part of the one or more platinum group metals are supported on a particulate support material as defined herein, it is preferred according to a second alternative that the SiC>2-doped AI2O3 comprises from 1 to 10 weight-%, preferably from 4 to 6 weight-%, of SiC>2 based on 100 weight-% of the SiC>2-doped AI2O3.

[0049] It is preferred that the catalyst further comprises a hydrocarbon trap material, wherein the hydrocarbon trap material is at least in part contained in one or more of:

[0050] (a) the first washcoat layer, and

[0051] (b) an optional second washcoat layer, or

[0052] (c) optional second and third washcoat layers.

[0053] In the case wherein the catalyst further comprises a hydrocarbon trap material as defined herein, it is preferred that the hydrocarbon trap material comprises a molecular sieve, preferably a zeolite, more preferably a zeolite having a maximum pore size of 12-membered rings, more preferably zeolite beta.

[0054] In the case wherein the hydrocarbon trap material comprises a molecular sieve, it is preferred that the molecular sieve, preferably the framework of the zeolite, comprises SiC>2 and AI2O3.

[0055] Further the case wherein the hydrocarbon trap material comprises a molecular sieve, it is preferred that the molecular sieve, preferably the zeolite, has a molar ratio of SiC>2 to AI2O3 in the range of from 10:1 to 500:1 , more preferably of from 10:1 to 100:1 , more preferably of from 10:1 to 40:1 , more preferably of from 15:1 to 30:1 , more preferably of from 20:1 to 25:1.

[0056] Further in the case wherein the hydrocarbon trap material comprises a molecular sieve, it is preferred that the molecular sieve, preferably the zeolite, comprises Fe, wherein the molecular sieve, preferably the zeolite, preferably comprises Fe, calculated as Fe2Os, in an amount in the range of from 1.0 to 7.0 weight-%, more preferably of from 3.0 to 5.0 weight-%, more preferably of from 4.0 to 4.5 weight-%, based on the weight of the molecular sieve.

[0057] Further in the case wherein the catalyst further comprises a hydrocarbon trap material as defined herein, it is preferred that the loading of the hydrocarbon trap material in the first washcoat layer and / or in each of the respective optional second or second and third washcoat layers is in the range of from 0.01 to 5.0 g / in3, preferably in the range of from 0.05 to 3.0 g / in3, more preferably in the range of from 0.1 to 2.0 g / in3, more preferably in the range of from 0.15 to 1 .0 g / in3, more preferably in the range of from 0.2 to 0.5 g / in3, more preferably in the range of from 0.22 to 0.3 g / in3, more preferably in the range of from 0.25 to 0.27 g / in3.

[0058] Further in the case wherein the catalyst further comprises a hydrocarbon trap material as defined herein, it is preferred that the catalyst comprises a second washcoat layer, wherein the hydrocarbon trap material is at least in part contained in the second washcoat layer. Further in the case wherein the catalyst further comprises a hydrocarbon trap material as defined herein, it is preferred that the catalyst comprises a third washcoat layer, wherein the hydrocarbon trap material is at least in part contained in the third washcoat layer.

[0059] In the case wherein the catalyst comprises a third washcoat layer, wherein the hydrocarbon trap material is at least in part contained in the third washcoat layer, it is preferred that the catalyst comprises second and third washcoat layers, wherein the hydrocarbon trap material is at least in part contained in the second and third washcoat layers.

[0060] It is preferred that the catalyst further comprises a sulfur-trap material, wherein the sulfur-trap material is at least in part contained in one or more of:

[0061] (a) the first washcoat layer, and

[0062] (b) an optional second washcoat layer, or

[0063] (c) optional second and third washcoat layers.

[0064] In the case wherein the catalyst further comprises a sulfur-trap material as defined herein, it is preferred that the content of the sulfur-trap material independently from one another in the first, second and third washcoat layers is in the range of from 5 to 75 wt.-% based on 100 wt.-% of the respective washcoat layer, preferably from 10 to 50 wt.-%, more preferably from 15 to 40 wt.-%, more preferably from 20 to 30 wt.-%.

[0065] Further in the case wherein the catalyst further comprises a sulfur-trap material as defined herein, it is preferred that the sulfur-trap material comprises one or more metal oxides which react with SO2 and / or SO3 to form corresponding metal sulfites and / or sulfates, wherein more preferably the sulfur-trap material consists of the one or more metal oxides.

[0066] In the case wherein the sulfur-trap material comprises one or more metal oxides which react with SO2 and / or SO3 to form corresponding metal sulfites and / or sulfates, it is preferred that each of the one or more metal oxides, which react with SO2 and / or SO3 to form corresponding metal sulfite and / or sulfate, displays a desulfation temperature T50, at which 50% of the respective metal sulfite and / or metal sulfate has decomposed to the metal oxide and SO2 and / or SO3, which is lower than the desulfation temperature T50 of MnSC , wherein more preferably, each of the one or more metal oxides displays a desulfation temperature T50 which is at least 10°C lower than the desulfation temperature T50 of MnSC , more preferably at least 20°C lower, more preferably at least 50°C lower, more preferably at least 80°C lower, more preferably at least 100°C lower, more preferably at least 150°C lower.

[0067] Further in the case wherein the sulfur-trap material comprises one or more metal oxides which react with SO2 and / or SO3 to form corresponding metal sulfites and / or sulfates, it is preferred that the one or more metal oxides are selected from the group consisting of oxides of Cu, Ni, Co, Fe, and Sn, including mixtures of two or more thereof, more preferably from the group consisting of oxides of Cu, Fe, and Sn, including mixtures of two or more thereof, wherein more preferably the one or more metal oxides comprise, more preferably consist of, oxides of Fe.

[0068] In the case wherein the one or more metal oxides are selected from the group consisting of oxides of Cu, Ni, Co, Fe, and Sn, including mixtures of two or more thereof, it is preferred according to a first alternative that the one or more metal oxides are selected from the group consisting of Fe20s, CuO, SnO, and SnO2, including mixtures of two or more thereof, wherein more preferably the one or more metal oxides comprise, preferably consist of Fe20s.

[0069] Further in the case wherein the one or more metal oxides are selected from the group consisting of oxides of Cu, Ni, Co, Fe, and Sn, including mixtures of two or more thereof, it is preferred that the one or more metal oxides comprise, more preferably consist of, oxides of Fe, wherein more preferably the one or more metal oxides comprise, more preferably consist of, Fe20s and / or Fe2O3-doped AI2O3, more preferably comprise, preferably consist of, Fe20s.

[0070] In the case wherein the one or more metal oxides comprise, more preferably consist of, oxides of Fe, it is preferred that the content of the one or more oxides of Fe independently from one another in the first, second and third washcoat layers, calculated as Fe20s and based on 100 wt.- % of the respective washcoat layer, is in the range of from 1 to 100 wt.-%, more preferably from 5 to 75 wt.-%, more preferably from 10 to 50 wt.-%, more preferably from 15 to 40 wt.-%, more preferably from 20 to 30 wt.-%.

[0071] Further in the case wherein the one or more metal oxides comprise, more preferably consist of, oxides of Fe, it is preferred that the one or more oxides of Fe display an average particle size D50 of 20 pm or less, more preferably of 10 pm or less, more preferably of 5 pm or less, more preferably of 1 pm or less, wherein the average particle size is more preferably determined according to ISO 13320:2020.

[0072] Further in the case wherein the one or more metal oxides comprise, more preferably consist of, oxides of Fe, it is preferred that the one or more metal oxides of Fe are supported on a particulate support material, wherein the particulate support material is preferably selected from the group consisting of ZrC>2, AI2O3, SiC>2, SiO2-AhO3, TiC>2, La2O3-doped ZrC>2, CeO2-ZrO2 mixed oxide, La2C>3-doped CeO2-ZrO2 mixed oxide, Nd2Os-doped CeO2-ZrO2 mixed oxide, Y2Os-doped CeO2-ZrC>2 mixed oxide, praseodymium oxide-doped CeO2-ZrO2 mixed oxide, ZrC>2-doped AI2O3, ZrC>2-doped SiC>2, SiC>2-doped AI2O3, CUO-AI2O3 mixed oxide, and mixtures of two or more thereof, more preferably from the group consisting of AI2O3, SiC>2, SiO2-AhO3, La20s- doped ZrC>2, CeO2-ZrO2 mixed oxide, La2C>3-doped CeO2-ZrO2 mixed oxide, and mixtures of two or more thereof, more preferably from the group consisting of AI2O3, SiO2-AhO3, La2C>3-doped ZrC>2, CeO2-ZrC>2 mixed oxide, and mixtures of two or more thereof, wherein more preferably Fe is supported on particulate La2C>3-doped ZrC>2. Further in the case wherein the one or more metal oxides are selected from the group consisting of oxides of Cu, Ni, Co, Fe, and Sn, including mixtures of two or more thereof, it is preferred according to a second alternative that the one or more metal oxides comprise, preferably consist of, oxides of Sn, preferably of SnO, SnC>2, or SnO and SnC>2.

[0073] In the case wherein the one or more metal oxides comprise, preferably consist of oxides of Sn as defined herein, it is preferred that the oxides of Sn are supported on a particulate support material, wherein the particulate support material is more preferably selected from the group consisting of ZrC>2, AI2O3, SiC>2, SiC^-AhOs, TiC>2, La2O3-doped ZrC>2, CeO2-ZrO2 mixed oxide, La2C>3-doped CeO2-ZrO2 mixed oxide, Nd2Os-doped CeO2-ZrO2 mixed oxide, Y2C>3-doped CeC>2- ZrC>2 mixed oxide, praseodymium oxide-doped CeO2-ZrO2 mixed oxide, ZrC>2-doped AI2O3, ZrC>2-doped SiC>2, SiC>2-doped AI2O3, CUO-AI2O3 mixed oxide, and mixtures of two or more thereof, more preferably from the group consisting of AI2O3, SiC>2, SiC^-AhOs, La2C>3-doped ZrC>2, CeO2-ZrC>2 mixed oxide, La2C>3-doped CeO2-ZrO2 mixed oxide, and mixtures of two or more thereof, more preferably from the group consisting of AI2O3, SiC^-AhOs, La2C>3-doped ZrC>2, CeO2-ZrC>2 mixed oxide, and mixtures of two or more thereof, wherein more preferably Sn is supported on particulate La2C>3-doped ZrC>2.

[0074] It is preferred that the catalyst comprises a second washcoat layer, wherein the one or more platinum group metals are at least in part contained in the second washcoat layer, wherein more preferably the one or more platinum group metals are entirely contained in the second washcoat layer.

[0075] In the case wherein the catalyst comprises a second washcoat layer, wherein the one or more platinum group metals are at least in part contained in the second washcoat layer, wherein more preferably the one or more platinum group metals are entirely contained in the second washcoat layer, it is preferred that the second washcoat layer is provided on the substrate, and the first washcoat layer is provided on the second washcoat layer.

[0076] According to a first alternative, it is preferred that the catalyst comprises a second washcoat layer, wherein the catalyst displays a layered arrangement of the first and second washcoat layers, and wherein the one or more platinum group metals are at least in part contained in the second washcoat layer.

[0077] In the case wherein the catalyst comprises a second washcoat layer, wherein the catalyst displays a layered arrangement of the first and second washcoat layers, and wherein the one or more platinum group metals are at least in part contained in the second washcoat layer, in accordance with the first alternative, it is preferred according to an alternative that the first washcoat layer is provided on the substrate, and the second washcoat layer is provided on the first washcoat layer. Further in the case wherein the catalyst comprises a second washcoat layer, wherein the catalyst displays a layered arrangement of the first and second washcoat layers, and wherein the one or more platinum group metals are at least in part contained in the second washcoat layer, in accordance with the first alternative, it is preferred according to a further alternative that the second washcoat layer is provided on the substrate, and the first washcoat layer is provided on the second washcoat layer.

[0078] Further in the case wherein the catalyst comprises a second washcoat layer, wherein the catalyst displays a layered arrangement of the first and second washcoat layers, and wherein the one or more platinum group metals are at least in part contained in the second washcoat layer, in accordance with the first alternative, wherein the first washcoat layer is preferably provided on the substrate, and the second washcoat layer is preferably provided on the first washcoat layer, it is preferred according to a further alternative that the catalyst comprises a third washcoat layer, wherein the catalyst displays a zoned arrangement of the first, second, and third washcoat layers, wherein the third washcoat layer is provided on the substrate along its axial length starting from the inlet end of the substrate and wherein the first washcoat layer is provided on the substrate along its axial length starting from the outlet end of the substrate, and wherein the second washcoat layer is provided on and entirely covers the first washcoat layer, wherein the length of the first washcoat layer is less than the axial length of the substrate such as to create an upstream zone comprising the third washcoat layer and a downstream zone comprising the first and second washcoat layers, and wherein the one or more platinum group metals are at least in part contained in the third washcoat layer.

[0079] Further in the case wherein the catalyst comprises a second washcoat layer, wherein the catalyst displays a layered arrangement of the first and second washcoat layers, and wherein the one or more platinum group metals are at least in part contained in the second washcoat layer, in accordance with the first alternative, wherein the second washcoat layer is preferably provided on the substrate, and the first washcoat layer is preferably provided on the second washcoat layer, it is preferred according to a further alternative that the catalyst comprises a third washcoat layer, wherein the catalyst displays a zoned arrangement of the first, second, and third washcoat layers, wherein the third washcoat layer is provided on the substrate along its axial length starting from the inlet end of the substrate and wherein the second washcoat layer is provided on the substrate along its axial length starting from the outlet end of the substrate, and wherein the first washcoat layer is provided on and entirely covers the second washcoat layer, wherein the length of the second washcoat layer is less than the axial length of the substrate such as to create an upstream zone comprising the third washcoat layer and a downstream zone comprising the first and second washcoat layers, and wherein the one or more platinum group metals are at least in part contained in the third washcoat layer.

[0080] Further in the case wherein the catalyst comprises a second washcoat layer, wherein the catalyst displays a layered arrangement of the first and second washcoat layers, and wherein the one or more platinum group metals are at least in part contained in the second washcoat layer, in accordance with the first alternative, wherein the first washcoat layer is preferably provided on the substrate, and the second washcoat layer is preferably provided on the first washcoat layer, it is preferred according to a further alternative that the catalyst comprises a third washcoat layer, wherein the catalyst displays a zoned arrangement of the first, second, and third washcoat layers, wherein the third washcoat layer is provided on the substrate along its axial length starting from the outlet end of the substrate and wherein the first washcoat layer is provided on the substrate along its axial length starting from the inlet end of the substrate, and wherein the second washcoat layer is provided on and entirely covers the first washcoat layer, wherein the length of the first washcoat layer is less than the axial length of the substrate such as to create a downstream zone comprising the third washcoat layer and an upstream zone comprising the first and second washcoat layers, and wherein the one or more platinum group metals are at least in part contained in the third washcoat layer.

[0081] Further in the case wherein the catalyst comprises a second washcoat layer, wherein the catalyst displays a layered arrangement of the first and second washcoat layers, and wherein the one or more platinum group metals are at least in part contained in the second washcoat layer, in accordance with the first alternative, wherein the second washcoat layer is preferably provided on the substrate, and the first washcoat layer is preferably provided on the second washcoat layer, it is preferred according to a further alternative that the catalyst comprises a third washcoat layer, wherein the catalyst displays a zoned arrangement of the first, second, and third washcoat layers, wherein the third washcoat layer is provided on the substrate along its axial length starting from the outlet end of the substrate and wherein the second washcoat layer is provided on the substrate along its axial length starting from the inlet end of the substrate, and wherein the first washcoat layer is provided on and entirely covers the second washcoat layer, wherein the length of the second washcoat layer is less than the axial length of the substrate such as to create a downstream zone comprising the third washcoat layer and an upstream zone comprising the first and second washcoat layers, and wherein the one or more platinum group metals are at least in part contained in the third washcoat layer.

[0082] According to a second alternative, it is preferred that the catalyst comprises a second washcoat layer, wherein the catalyst displays a zoned arrangement of the first and second washcoat layers, wherein the second washcoat layer is provided on the substrate along its axial length starting from the inlet end of the substrate, and wherein the first washcoat layer is provided on the substrate along its axial length starting from the outlet end of the substrate, wherein the length of the first washcoat layer is less than the axial length of the substrate such as to create an upstream zone comprising the second washcoat layer and a downstream zone comprising the first washcoat layer, and wherein the one or more platinum group metals are at least in part contained in the second washcoat layer.

[0083] According to a third alternative, it is preferred that catalyst comprises a second washcoat layer, wherein the catalyst displays a zoned arrangement of the first and second washcoat layers, wherein the first washcoat layer is provided on the substrate along its axial length starting from the inlet end of the substrate, and wherein the second washcoat layer is provided on the substrate along its axial length starting from the outlet end of the substrate, wherein the length of the first washcoat layer is less than the axial length of the substrate such as to create an upstream zone comprising the first washcoat layer and a downstream zone comprising the second washcoat layer, and wherein the one or more platinum group metals are at least in part contained in the second washcoat layer.

[0084] According to a fourth alternative, it is preferred that the catalyst comprises a second washcoat layer, wherein the catalyst displays a zoned arrangement of the first and second washcoat layers, wherein the second washcoat layer is provided on the substrate along its axial length starting from the inlet end of the substrate, and wherein the first washcoat layer is provided on the substrate along its axial length starting from the outlet end of the substrate, wherein the length of the second washcoat layer is less than the axial length of the substrate such as to create an upstream zone comprising the second washcoat layer and a downstream zone comprising the first washcoat layer, and wherein the one or more platinum group metals are at least in part contained in the second washcoat layer.

[0085] According to a fifth alternative, it is preferred that the catalyst comprises a second washcoat layer, wherein the catalyst displays a zoned arrangement of the first and second washcoat layers, wherein the first washcoat layer is provided on the substrate along its axial length starting from the inlet end of the substrate, and wherein the second washcoat layer is provided on the substrate along its axial length starting from the outlet end of the substrate, wherein the length of the second washcoat layer is less than the axial length of the substrate such as to create an upstream zone comprising the first washcoat layer and a downstream zone comprising the second washcoat layer, and wherein the one or more platinum group metals are at least in part contained in the second washcoat layer.

[0086] In the case wherein the catalyst comprises optional second and third washcoat layers according to the second or fourth alternative as defined herein, it is preferred that the catalyst comprises a third washcoat layer, wherein the third washcoat layer is provided on the first washcoat layer, wherein the catalyst displays a zoned arrangement of the second and third washcoat layers, wherein the second washcoat layer is provided on the substrate along the axial length of the substrate starting from the inlet end of the substrate, and wherein the third washcoat layer is provided on the first washcoat layer along the axial length of the substrate starting from the outlet end of the substrate, wherein the length of the third washcoat layer is less than the axial length of the substrate such as to create an upstream zone comprising the second washcoat layer and a downstream zone comprising the first and third washcoat layers.

[0087] In the case wherein the catalyst comprises optional second and third washcoat layers according to the second or fourth alternative as defined herein, it is preferred that the catalyst comprises a third washcoat layer, wherein the third washcoat layer is provided on the first washcoat layer, wherein the catalyst displays a zoned arrangement of the second and third washcoat layers, wherein the third washcoat layer is provided on the first washcoat layer along the axial length of the substrate starting from the inlet end of the substrate, and wherein the second washcoat layer is provided on the substrate along the axial length of the substrate starting from the outlet end of the substrate, wherein the length of the third washcoat layer is less than the axial length of the substrate such as to create an upstream zone comprising the first and third washcoat layers and a downstream zone comprising the second washcoat layer.

[0088] In the case wherein the catalyst comprises optional second and third washcoat layers according to the second, third, fourth or fifth alternative as defined herein, it is preferred that the first and second washcoat layers are adjacent to one another.

[0089] In the case wherein the catalyst comprises optional second and third washcoat layers according to the first alternative as defined herein, it is preferred that the first and third washcoat layers are adjacent to one another.

[0090] In the case wherein the catalyst comprises optional second and third washcoat layers according to the first, second, third, fourth or fifth alternative as defined herein, it is preferred that the second and third washcoat layers are adjacent to one another.

[0091] In the case wherein the catalyst comprises optional second and third washcoat layers according to the second, third, fourth or fifth alternative as defined herein, it is preferred that a portion of the second washcoat layer overlaps at least a portion of the first washcoat layer, wherein preferably the second washcoat layer overlaps the first washcoat layer over a portion ranging from 10 to 100% of the axial length of the first washcoat layer, more preferably from 15 to 80%, more preferably from 20 to 50%.

[0092] In the case wherein the catalyst comprises optional second and third washcoat layers according to the second, third, fourth or fifth alternative as defined herein, it is preferred that a portion of the first washcoat layer overlaps at least a portion of the second washcoat layer, wherein more preferably the first washcoat layer overlaps the second washcoat layer over a portion ranging from 10 to 100% of the axial length of the second washcoat layer, more preferably from 15 to 80%, more preferably from 20 to 50%.

[0093] In the case wherein the catalyst comprises optional second and third washcoat layers according to the first, second, third, fourth or fifth alternative as defined herein, wherein the catalyst comprises a third washcoat layer, it is preferred that a portion of the third washcoat layer overlaps at least a portion of the first washcoat layer, wherein more preferably the third washcoat layer overlaps the first washcoat layer over a portion ranging from 10 to 100% of the axial length of the first washcoat layer, more preferably from 15 to 80%, more preferably from 20 to 50%. According to a sixth alternative, it is preferred that the catalyst comprises a second washcoat layer, wherein the catalyst displays a zoned arrangement of the first and second washcoat layers, wherein the second washcoat layer is provided on the substrate along its entire length, and wherein the first washcoat layer is provided on the second washcoat layer along its axial length starting from the outlet end of the substrate, wherein the length of the first washcoat layer is less than the axial length of the substrate such as to create an upstream zone comprising the second washcoat layer and a downstream zone comprising the first washcoat layer, and wherein the one or more platinum group metals are at least in part contained in the second washcoat layer.

[0094] According to a seventh alternative, it is preferred that the catalyst comprises a second washcoat layer, wherein the catalyst displays a zoned arrangement of the first and second washcoat layers, wherein the second washcoat layer is provided on the substrate along its entire length, and wherein the first washcoat layer is provided on the second washcoat layer along its axial length starting from the inlet end of the substrate, wherein the length of the first washcoat layer is less than the axial length of the substrate such as to create an upstream zone comprising the first washcoat layer and a downstream zone comprising the second washcoat layer, and wherein the one or more platinum group metals are at least in part contained in the second washcoat layer.

[0095] In the case wherein the catalyst comprises optional second washcoat layer according to the sixth or seventh alternative as defined herein, it is preferred that the length of the first washcoat layer ranges from 10 to 90% of the axial length of the substrate, more preferably from 30 to 80%, more preferably from 50 to 70%.

[0096] According to an eighth alternative, it is preferred that the catalyst comprises a second washcoat layer, wherein the catalyst displays a zoned arrangement of the first and second washcoat layers, wherein the first washcoat layer is provided on the substrate along its entire length, and wherein the second washcoat layer is provided on the first washcoat layer along its axial length starting from the inlet end of the substrate, wherein the length of the second washcoat layer is less than the axial length of the substrate such as to create an upstream zone comprising the second washcoat layer and a downstream zone comprising the first washcoat layer, and wherein the one or more platinum group metals are at least in part contained in the second washcoat layer.

[0097] In the case wherein the catalyst comprises a second washcoat layer according to the eighth alternative as defined herein, it is preferred that the catalyst comprises a third washcoat layer, wherein the third washcoat layer is provided on the first washcoat layer, wherein the catalyst displays a zoned arrangement of the second and third washcoat layers, wherein the second washcoat layer is provided on the first washcoat layer along the axial length of the substrate starting from the inlet end of the substrate, and wherein the third washcoat layer is provided on the first washcoat layer along the axial length of the substrate starting from the outlet end of the substrate, wherein the length of the third washcoat layer is less than the axial length of the substrate such as to create an upstream zone comprising the second washcoat layer and a downstream zone comprising the third washcoat layer.

[0098] According to a ninth alternative, it is preferred that the catalyst comprises a second washcoat layer, wherein the catalyst displays a zoned arrangement of the first and second washcoat layers, wherein the first washcoat layer is provided on the substrate along its entire length, and wherein the second washcoat layer is provided on the first washcoat layer along its axial length starting from the outlet end of the substrate, wherein the length of the second washcoat layer is less than the axial length of the substrate such as to create an upstream zone comprising the first washcoat layer and a downstream zone comprising the second washcoat layer, and wherein the one or more platinum group metals are at least in part contained in the second washcoat layer.

[0099] In the case wherein the catalyst comprises a second washcoat layer according to the ninth alternative as defined herein, it is preferred that the catalyst comprises a third washcoat layer, wherein the third washcoat layer is provided on the first washcoat layer, wherein the catalyst displays a zoned arrangement of the second and third washcoat layers, wherein the third washcoat layer is provided on the first washcoat layer along the axial length of the substrate starting from the inlet end of the substrate, and wherein the second washcoat layer is provided on the first washcoat layer along the axial length of the substrate starting from the outlet end of the substrate, wherein the length of the third washcoat layer is less than the axial length of the substrate such as to create an upstream zone comprising the third washcoat layer and a downstream zone comprising the second washcoat layer.

[0100] In the case wherein the catalyst comprises second and third washcoat layers according to the eighth or ninth alternative as defined herein, it is preferred that the second and third washcoat layers are adjacent to one another.

[0101] According to a tenth alternative, wherein the catalyst comprises second and third washcoat layers, wherein the catalyst preferably displays a layered arrangement of the first and second washcoat layers, and wherein the one or more platinum group metals are preferably at least in part contained in the second washcoat layer, in accordance with the first alternative as defined herein, it is preferred that the first washcoat layer is provided on the substrate, wherein the second washcoat layer is at least partially, preferably completely, provided on the first washcoat layer, and wherein the third washcoat layer is at least partially, preferably completely, provided on the second washcoat layer.

[0102] According to an eleventh alternative, wherein the catalyst comprises second and third washcoat layers, wherein the catalyst preferably displays a layered arrangement of the first and second washcoat layers, and wherein the one or more platinum group metals are preferably at least in part contained in the second washcoat layer, in accordance with the first alternative as defined herein, it is preferred that the first washcoat layer is provided on the substrate, wherein the third washcoat layer is at least partially, preferably completely, provided on the first washcoat layer, and wherein the second washcoat layer is at least partially, preferably completely, provided on the third washcoat layer.

[0103] It is preferred that the length of the first washcoat layer ranges from 5 to 100% of the axial length of the substrate, more preferably from 10 to 90% of the axial length of the substrate, preferably from 15 to 75%, more preferably from 20 to 60%, more preferably from 25 to 50%, more preferably from 35 to 45%.

[0104] In the case wherein the catalyst comprises a second washcoat layer, it is preferred that the length of the second washcoat layer ranges from 5 to 100% of the axial length of the substrate, more preferably from 10 to 90% of the axial length of the substrate, more preferably from 15 to 75%, more preferably from 20 to 60%, more preferably from 25 to 50%, more preferably from 35 to 45%.

[0105] In the case wherein the catalyst comprises a third washcoat layer, it is preferred that the length of the third washcoat layer ranges from 5 to 100% of the axial length of the substrate, more preferably from 10 to 90% of the axial length of the substrate, preferably from 15 to 75%, more preferably from 20 to 60%, more preferably from 25 to 50%, more preferably from 35 to 45%.

[0106] In the case wherein the catalyst comprises a third washcoat layer, in accordance with the first, second, third, fourth, fifth, sixth, seventh, eighth, ninth, tenth, or eleventh alternative it is preferred that the one or more platinum group metals are at least in part contained in the third washcoat layer.

[0107] In the case wherein the catalyst comprises second and third washcoat layers, in accordance with the first, second, third, fourth, fifth, sixth, seventh, eighth, ninth, tenth, or eleventh alternative, it is preferred that the catalyst comprises second and third washcoat layers, wherein the one or more platinum group metals are entirely contained in the second and third washcoat layers.

[0108] In the case wherein the catalyst comprises second and third washcoat layers, wherein the one or more platinum group metals are entirely contained in the second and third washcoat layers, it is preferred that the weight ratio of the one or more platinum group metals comprised in the second washcoat layer to the one or more platinum group metals comprised in the third washcoat layer is in the range of from 0.5:1 to 5.0:1 , more preferably 1 .0:1 to 2.0:1 , more preferably in the range of from 1.4:1 to 1.6:1 , wherein the one or more platinum group metals comprised in the second washcoat layer preferably comprise, more preferably consist of, Pt and Pd, wherein the one or more platinum group metals comprised in the third washcoat layer preferably comprise, more preferably consist of, Pt and Pd.

[0109] It is preferred that the substrate is a metallic substrate or a ceramic substrate, wherein more preferably the substrate is a ceramic substrate, wherein more preferably the substrate comprises cordierite and / or SiC, preferably cordierite, wherein more preferably, the substrate consists cordierite and / or SiC, preferably of cordierite.

[0110] In the case wherein the catalyst comprises a second washcoat layer and optionally a third washcoat layer, in accordance with the first, second, third, fourth, fifth, sixth, seventh, eighth, ninth, tenth, or eleventh alternative, wherein the catalyst displays a zoned arrangement of the first and second washcoat layers, of the second and third washcoat layers, and / or of the first and third washcoat layers, it is preferred that the substrate consists of two separate monoliths, wherein the first monolith is provided upstream of the second monolith, wherein the washcoat layer or washcoat layers of the upstream zone are contained on the first monolith, and the washcoat layer or washcoat layers of the downstream zone are contained on the second monolith, wherein preferably the first monolith containing the washcoat layer or washcoat layers of the upstream zone and the second monolith containing the washcoat layer or washcoat layers of the downstream zone are obtained or obtainable by sectioning of a catalyst comprising a second washcoat layer and optionally a third washcoat layer, in accordance with the first, second, third, fourth, fifth, sixth, seventh, eighth, ninth, tenth, or eleventh alternative, wherein the catalyst displays a zoned arrangement of the first and second washcoat layers, of the second and third washcoat layers, and / or of the first and third washcoat layers, into two separate monoliths, wherein the washcoat layer or washcoat layers of the upstream zone are contained on the first monolith, and the washcoat layer or washcoat layers of the downstream zone are contained on the second monolith.

[0111] It is preferred that the exhaust gas stream contains hydrocarbons, more preferably C1 to C20 hydrocarbons, more preferably C2 to C10 hydrocarbons.

[0112] Further, the present invention relates to an exhaust gas treatment system comprising an internal combustion engine and an exhaust gas conduit for exhaust gas from the internal combustion engine, wherein the exhaust gas conduit comprises one or more catalysts according to any one of the embodiments defined herein, preferably one, two, three or four catalysts according to any one of the embodiments defined herein.

[0113] According to a first alternative, it is preferred that the internal combustion engine is a compression ignition engine, more preferably a diesel engine. According to a second alternative, wherein the internal combustion engine optionally is a compression ignition engine, optionally a diesel engine, according to the first alternative, it is preferred that the internal combustion engine is a lean gasoline engine.

[0114] According to a third alternative, it is preferred that the internal combustion engine is powered by an oxygenated fuel, wherein the oxygenated fuel more preferably comprises one or more of methanol and biofuel.

[0115] It is preferred that the system comprises one or more of an electric heater, a fuel burner, a fuel injector, a selective catalytic reduction (SCR) catalyst, an ammonia oxidation (AMOX) catalyst, a catalyzed soot filter (CSF), a diesel particulate filter (DPF), a selective catalytic reduction catalyst on filter (SCRoF), and a diesel exotherm catalyst (DEC).

[0116] According to a first alternative for the exhaust gas treatment system, in the case wherein the system comprises one or more of an electric heater, a fuel burner, a fuel injector, a selective catalytic reduction (SCR) catalyst, an ammonia oxidation (AMOX) catalyst, a catalyzed soot filter (CSF), a diesel particulate filter (DPF), a selective catalytic reduction catalyst on filter (SCRoF), and a diesel exotherm catalyst (DEC), it is preferred that the exhaust gas treatment system comprises in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a catalyst according to any of the embodiments defined herein, a catalyst according to any of the embodiments defined herein, a selective catalytic reduction (SCR) catalyst, a selective catalytic reduction (SCR) catalyst, an optional fuel injector, a diesel exotherm catalyst (DEC), a catalyzed soot filter (CSF), a selective catalytic reduction (SCR) catalyst, and a selective catalytic reduction (SCR) catalyst.

[0117] According to a second alternative for the exhaust gas treatment system, in the case wherein the system comprises one or more of an electric heater, a fuel burner, a fuel injector, a selective catalytic reduction (SCR) catalyst, an ammonia oxidation (AMOX) catalyst, a catalyzed soot filter (CSF), a diesel particulate filter (DPF), a selective catalytic reduction catalyst on filter (SCRoF), and a diesel exotherm catalyst (DEC), it is preferred that the exhaust gas treatment system comprises in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a catalyst according to any of the embodiments defined herein, a catalyst according to any of the embodiments defined herein, a selective catalytic reduction (SCR) catalyst, a selective catalytic reduction (SCR) catalyst, an optional fuel injector, a diesel exotherm catalyst (DEC), a diesel particulate filter (DPF), a selective catalytic reduction (SCR) catalyst, and a selective catalytic reduction (SCR) catalyst.

[0118] According to a third alternative for the exhaust gas treatment system, in the case wherein the system comprises one or more of an electric heater, a fuel burner, a fuel injector, a selective catalytic reduction (SCR) catalyst, an ammonia oxidation (AMOX) catalyst, a catalyzed soot filter (CSF), a diesel particulate filter (DPF), a selective catalytic reduction catalyst on filter (SCRoF), and a diesel exotherm catalyst (DEC), it is preferred that the exhaust gas treatment system comprises in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a catalyst according to any of the embodiments defined herein, a catalyst according to any of the embodiments defined herein, a selective catalytic reduction (SCR) catalyst, a selective catalytic reduction (SCR) catalyst, an optional fuel injector, a diesel exotherm catalyst (DEC), a diesel particulate filter (DPF), a selective catalytic reduction (SCR) catalyst, and an ammonia oxidation (AMOX) catalyst.

[0119] According to a fourth alternative for the exhaust gas treatment system, in the case wherein the system comprises one or more of an electric heater, a fuel burner, a fuel injector, a selective catalytic reduction (SCR) catalyst, an ammonia oxidation (AMOX) catalyst, a catalyzed soot filter (CSF), a diesel particulate filter (DPF), a selective catalytic reduction catalyst on filter (SCRoF), and a diesel exotherm catalyst (DEC), it is preferred that the exhaust gas treatment system comprises in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a catalyst according to any of the embodiments defined herein, a catalyst according to any of the embodiments defined herein, a selective catalytic reduction (SCR) catalyst, a selective catalytic reduction (SCR) catalyst, an optional fuel injector, a catalyst according to any of the embodiments defined herein, a diesel particulate filter (DPF), a selective catalytic reduction (SCR) catalyst, and a selective catalytic reduction (SCR) catalyst.

[0120] According to a fifth alternative for the exhaust gas treatment system, in the case wherein the system comprises one or more of an electric heater, a fuel burner, a fuel injector, a selective catalytic reduction (SCR) catalyst, an ammonia oxidation (AMOX) catalyst, a catalyzed soot filter (CSF), a diesel particulate filter (DPF), a selective catalytic reduction catalyst on filter (SCRoF), and a diesel exotherm catalyst (DEC), it is preferred that the exhaust gas treatment system comprises in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a catalyst according to any of the embodiments defined herein, a catalyst according to any of the embodiments defined herein, a selective catalytic reduction (SCR) catalyst, a selective catalytic reduction (SCR) catalyst, an optional fuel injector, a catalyst according to any of the embodiments defined herein, a catalyst according to any of the embodiments defined herein, wherein the substrate is a wall-flow substrate, a selective catalytic reduction (SCR) catalyst, and an ammonia oxidation (AMOX) catalyst.

[0121] According to a sixth alternative for the exhaust gas treatment system, in the case wherein the system comprises one or more of an electric heater, a fuel burner, a fuel injector, a selective catalytic reduction (SCR) catalyst, an ammonia oxidation (AMOX) catalyst, a catalyzed soot filter (CSF), a diesel particulate filter (DPF), a selective catalytic reduction catalyst on filter (SCRoF), and a diesel exotherm catalyst (DEC), it is preferred that the exhaust gas treatment system comprises in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a catalyst according to any of the embodiments defined herein, a selective catalytic reduction (SCR) catalyst, a selective catalytic reduction (SCR) catalyst, a catalyzed soot filter (CSF), a selective catalytic reduction (SCR) catalyst, and a selective catalytic reduction (SCR) catalyst.

[0122] According to a seventh alternative for the exhaust gas treatment system, in the case wherein the system comprises one or more of an electric heater, a fuel burner, a fuel injector, a selective catalytic reduction (SCR) catalyst, an ammonia oxidation (AMOX) catalyst, a catalyzed soot filter (CSF), a diesel particulate filter (DPF), a selective catalytic reduction catalyst on filter (SCRoF), and a diesel exotherm catalyst (DEC), it is preferred that the exhaust gas treatment system comprises in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a catalyst according to any of the embodiments defined herein, a selective catalytic reduction (SCR) catalyst, a selective catalytic reduction (SCR) catalyst, a catalyzed soot filter (CSF), a selective catalytic reduction (SCR) catalyst, and an ammonia oxidation (AMOX) catalyst.

[0123] According to an eighth alternative for the exhaust gas treatment system, in the case wherein the system comprises one or more of an electric heater, a fuel burner, a fuel injector, a selective catalytic reduction (SCR) catalyst, an ammonia oxidation (AMOX) catalyst, a catalyzed soot filter (CSF), a diesel particulate filter (DPF), a selective catalytic reduction catalyst on filter (SCRoF), and a diesel exotherm catalyst (DEC), it is preferred that the exhaust gas treatment system comprises in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a catalyst according to any of the embodiments defined herein, a selective catalytic reduction (SCR) catalyst, a selective catalytic reduction (SCR) catalyst, an optional fuel injector, a catalyst according to any of the embodiments defined herein, wherein the substrate is a wall-flow substrate, a selective catalytic reduction (SCR) catalyst, and an ammonia oxidation (AMOX) catalyst.

[0124] According to a ninth alternative for the exhaust gas treatment system, in the case wherein the system comprises one or more of an electric heater, a fuel burner, a fuel injector, a selective catalytic reduction (SCR) catalyst, an ammonia oxidation (AMOX) catalyst, a catalyzed soot filter (CSF), a diesel particulate filter (DPF), a selective catalytic reduction catalyst on filter (SCRoF), and a diesel exotherm catalyst (DEC), it is preferred that the exhaust gas treatment system comprises in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a catalyst according to any of the embodiments defined herein, a selective catalytic reduction (SCR) catalyst, a selective catalytic reduction catalyst on filter (SCRoF), and an ammonia oxidation (AMOX) catalyst.

[0125] According to a tenth alternative for the exhaust gas treatment system, in the case wherein the system comprises one or more of an electric heater, a fuel burner, a fuel injector, a selective catalytic reduction (SCR) catalyst, an ammonia oxidation (AMOX) catalyst, a catalyzed soot filter (CSF), a diesel particulate filter (DPF), a selective catalytic reduction catalyst on filter (SCRoF), and a diesel exotherm catalyst (DEC), it is preferred that the exhaust gas treatment system comprises in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a selective catalytic reduction (SCR) catalyst, an optional fuel injector, a catalyst according to any of the embodiments defined herein, a selective catalytic reduction catalyst on filter (SCRoF), and an ammonia oxidation (AMOX) catalyst.

[0126] According to an eleventh alternative for the exhaust gas treatment system, in the case wherein the system comprises one or more of an electric heater, a fuel burner, a fuel injector, a selective catalytic reduction (SCR) catalyst, an ammonia oxidation (AMOX) catalyst, a catalyzed soot filter (CSF), a diesel particulate filter (DPF), a selective catalytic reduction catalyst on filter (SCRoF), and a diesel exotherm catalyst (DEC), it is preferred that the exhaust gas treatment system comprises in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a selective catalytic reduction (SCR) catalyst, an optional fuel injector, a catalyst according to any of the embodiments defined herein, a catalyzed soot filter (CSF), a selective catalytic reduction (SCR) catalyst, and an ammonia oxidation (AMOX) catalyst.

[0127] According to a twelfth alternative for the exhaust gas treatment system, in the case wherein the system comprises one or more of an electric heater, a fuel burner, a fuel injector, a selective catalytic reduction (SCR) catalyst, an ammonia oxidation (AMOX) catalyst, a catalyzed soot filter (CSF), a diesel particulate filter (DPF), a selective catalytic reduction catalyst on filter (SCRoF), and a diesel exotherm catalyst (DEC), it is preferred that the exhaust gas treatment system comprises in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a selective catalytic reduction (SCR) catalyst, an optional fuel injector, a catalyst according to any of the embodiments defined herein, a catalyst according to any of the embodiments defined herein, wherein the substrate is a wall-flow substrate, a selective catalytic reduction (SCR) catalyst, and an ammonia oxidation (AMOX) catalyst.

[0128] According to a thirteenth alternative for the exhaust gas treatment system, in the case wherein the system comprises one or more of an electric heater, a fuel burner, a fuel injector, a selective catalytic reduction (SCR) catalyst, an ammonia oxidation (AMOX) catalyst, a catalyzed soot filter (CSF), a diesel particulate filter (DPF), a selective catalytic reduction catalyst on filter (SCRoF), and a diesel exotherm catalyst (DEC), it is preferred that the exhaust gas treatment system comprises in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a catalyst according to any of embodiments 1 to 85, a diesel particulate filter (DPF), a selective catalytic reduction (SCR) catalyst, a selective catalytic reduction (SCR) catalyst, a selective catalytic reduction (SCR) catalyst, a selective catalytic reduction (SCR) catalyst, and an ammonia oxidation (AMOX) catalyst.

[0129] According to a fourteenth alternative for the exhaust gas treatment system, in the case wherein the system comprises one or more of an electric heater, a fuel burner, a fuel injector, a selective catalytic reduction (SCR) catalyst, an ammonia oxidation (AMOX) catalyst, a catalyzed soot filter (CSF), a diesel particulate filter (DPF), a selective catalytic reduction catalyst on filter (SCRoF), and a diesel exotherm catalyst (DEC), it is preferred that the exhaust gas treatment system comprises in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a catalyst according to any of the embodiments defined herein, a selective catalytic reduction catalyst on filter (SCRoF), a selective catalytic reduction (SCR) catalyst, and an ammonia oxidation (AMOX) catalyst.

[0130] According to a fifteenth alternative for the exhaust gas treatment system, in the case wherein the system comprises one or more of an electric heater, a fuel burner, a fuel injector, a selective catalytic reduction (SCR) catalyst, an ammonia oxidation (AMOX) catalyst, a catalyzed soot filter (CSF), a diesel particulate filter (DPF), a selective catalytic reduction catalyst on filter (SCRoF), and a diesel exotherm catalyst (DEC), it is preferred that the exhaust gas treatment system comprises in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a catalyst according to any of the embodiments defined herein, a selective catalytic reduction (SCR) catalyst, a selective catalytic reduction catalyst on filter (SCRoF), a selective catalytic reduction (SCR) catalyst, and an ammonia oxidation (AMOX) catalyst.

[0131] Yet further, the present invention relates to a method for the treatment of an exhaust gas stream containing one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons, the method comprising

[0132] (A) providing an exhaust gas stream comprising one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons;

[0133] (B) directing the exhaust gas stream provided in (A) through a catalyst according to any of the embodiments defined herein.

[0134] It is preferred that the exhaust gas stream provided in (A) comprises one or more sulfur-containing compounds, more preferably SO2 and / or SO3.

[0135] It is preferred that the exhaust gas stream provided in (A) comprises NOX.

[0136] It is preferred that the exhaust gas stream provided in (A) comprises CO.

[0137] It is preferred that the exhaust gas stream provided in (A) comprises hydrocarbons, more preferably C1 to C20 hydrocarbons, more preferably C2 to C10 hydrocarbons.

[0138] Yet further, the present invention relates to use of a catalyst according to any of the embodiments defined herein for the oxidation of one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons, preferably for the oxidation of one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons in an exhaust gas stream, more preferably for the oxidation of one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons in the exhaust gas stream of an internal combustion engine, more preferably for the oxidation of one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons in the exhaust gas stream of a compression ignition engine, more preferably for the oxidation of one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons in the exhaust gas stream of a diesel engine.

[0139] The present invention is further illustrated by the following set of embodiments and combinations of embodiments resulting from the dependencies and back-references as indicated. In particular, it is noted that in each instance where a range of embodiments is mentioned, for example in the context of a term such as "The catalyst of any one of embodiments 1 to 4", every embodiment in this range is meant to be explicitly disclosed for the skilled person, i.e. the wording of this term is to be understood by the skilled person as being synonymous to "The catalyst of any one of embodiments 1 , 2, 3, and 4". Further, it is explicitly noted that the following set of embodiments represents a suitably structured part of the general description directed to preferred aspects of the present invention, and, thus, suitably supports, but does not represent the claims of the present invention.

[0140] 1 . A catalyst for the treatment of an exhaust gas stream containing one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons, the catalyst comprising a first washcoat layer comprising a perovskite, wherein the perovskite contains Mn , and a substrate, wherein the substrate has an inlet end through which the exhaust gas stream may enter the catalyst, and an outlet end through which the exhaust gas stream may exit the catalyst, wherein the catalyst further comprises one or more platinum group metals comprising Pt, Pd, or Pt and Pd, wherein the one or more platinum group metals are at least in part contained in one or more of:

[0141] (a) the first washcoat layer, and

[0142] (b) an optional second washcoat layer, or

[0143] (c) optional second and third washcoat layers.

[0144] 2. The catalyst of embodiment 1 , wherein the optional second washcoat layer is substantially free of a Mn-containing perovskite, wherein preferably the optional second washcoat layer is free of a Mn-containing perovskite, wherein the optional second washcoat layer is more preferably substantially free of Mn, wherein the optional second washcoat layer is more preferably free of Mn.

[0145] 3. The catalyst of embodiment 1 or 2, wherein the content of the Mn-containing perovskite in the first washcoat layer is in the range of from 10 to 99 wt.-% based on 100 wt.-% of the first washcoat layer, preferably from 20 to 95 wt.-%, more preferably from 30 to 75 wt.-%, more preferably from 40 to 60 wt.-%, more preferably from 45 to 50 wt.-%. The catalyst of any of embodiments 1 to 3, wherein the Mn-containing perovskite has the formula

[0146] (AyBl.y)l.xMnO3-z (I) wherein A is a transition metal and B is an alkaline earth metal, wherein y is in the range of from 0 to 1 , wherein x is in the range of from 0 to 0.10, and wherein z is in the range of from 0 to 0.5. The catalyst of embodiment 4, wherein y is in the range of from greater than 0 to 0.95, preferably of from 0.05 to 0.9, more preferably of from 0.1 to 0.8, more preferably of from 0.2 to 0.6, more preferably of from 0.3 to 0.5, more preferably of from 0.35 to 0.45, more preferably of from 0.38 to 0.42, wherein y more preferably is 0.40. The catalyst of embodiment 4 or 5, wherein x is in the range of from 0.01 to 0.09, more preferably of from 0.02 to 0.08, more preferably of from 0.03 to 0.07, more preferably of from 0.04 to 0.06, wherein x more preferably is 0.05. The catalyst of any of embodiments 4 to 6, wherein z is in the range of from greater than 0 to 0.5, preferably of from 0.1 to 0.4, more preferably of from 0.2 to 0.3. The catalyst of any of embodiments 4 to 7, wherein transition metal A is selected from the group consisting of Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and combinations of two or more thereof, preferably from the group consisting of Y, La, Ce, Pr, Nd, Pm, Sm, and combinations of two or more thereof, more preferably from the group consisting of La, Ce, Pr, Nd, and combinations of two or more thereof, wherein more preferably A is La and / or Ce, wherein more preferably A is La. The catalyst of any of embodiments 4 to 8, wherein the alkaline earth metal B is selected from the group consisting of Mg, Ca, Sr, Ba, and combinations of two or more thereof, preferably from the group consisting of Ca, Sr, Ba, and combinations of two or more thereof, wherein more preferably B is Sr and / or Ca, wherein more preferably B is Sr. The catalyst of any of embodiments 1 to 9, wherein the first washcoat layer further comprises a particulate metal oxide, wherein the particulate metal oxide is preferably substantially free of Mn, and wherein the particulate metal oxide is preferably selected from the group consisting of ZrC>2, AI2O3, SiC>2, TiC>2, La2O3-doped ZrC>2, CeO2-ZrO2 mixed oxide, La2C>3-doped CeO2-ZrO2 mixed oxide, Nd2Os-doped CeO2-ZrO2 mixed oxide, Y2Os-doped CeO2-ZrC>2 mixed oxide, praseodymium oxide-doped CeO2-ZrO2 mixed oxide, ZrC>2-doped AI2O3, ZrC>2-doped SiC>2, SiC>2-doped AI2O3, CUO-AI2O3 mixed oxide, and mixtures of two or more thereof, more preferably from the group consisting of ZrC>2, La2C>3-doped ZrC>2, CeO2-ZrC>2 mixed oxide, La2C>3-doped CeO2-ZrO2 mixed oxide, Nd2Os-doped CeO2-ZrO2 mixed oxide, Y2Os-doped CeO2-ZrO2 mixed oxide, P^Os-doped CeO2-ZrO2 mixed oxide, PreOn-doped CeO2-ZrO2 mixed oxide, PrC>2-doped CeO2-ZrO2 mixed oxide, ZrC>2-doped AI2O3, ZrC>2-doped SiC>2, and mixtures of two or more thereof, more preferably from the group consisting of ZrC>2, La2C>3-doped ZrC>2, CeO2-ZrO2 mixed oxide, La2C>3-doped CeC>2- ZrC>2 mixed oxide, Nd2Os-doped CeO2-ZrO2 mixed oxide, Y2Os-doped CeO2-ZrO2 mixed oxide, Pr2Os-doped CeO2-ZrO2 mixed oxide, P^On-doped CeO2-ZrO2 mixed oxide, and mixtures of two or more thereof, wherein more preferably the particulate metal oxide is La2C>3-doped ZrC>2, wherein more preferably the particulate metal oxide is ZrC>2 doped with La2C>3 in an amount ranging from 1 to 50 wt.% calculated as La20s and based on 100 wt.- % of ZrC>2 and La20s, preferably from 3 to 30 wt.-%, more preferably from 5 to 15 wt.-%, more preferably from 8 to 10 wt.-%. The catalyst of embodiment 10, wherein the particulate metal oxide has a BET surface area in the range of from 10 to 300 m2 / g, preferably of from 30 to 200 m2 / g, more preferably of from 50 to 150 m2 / g, more preferably of from 60 to 100 m2 / g, more preferably of from 70 to 80 m2 / g. The catalyst of embodiment 10 or 11 , wherein in first washcoat layer the weight ratio of the Mn-containing perovskite to the particulate metal oxide is in the range of from 5:95 to 95:5, preferably of from 10:90 to 90:10, more preferably of from 20:80 to 80:20, more preferably of from 30:70 to 70:30, more preferably of from 40:60 to 60:40, more preferably of from 45:55 to 55:45. The catalyst of any of embodiments 1 to 12, wherein the first washcoat layer is substantially free of Ce, wherein preferably the first washcoat layer is free of Ce. The catalyst of embodiment 13, wherein the catalyst is substantially free of Ce, wherein preferably the catalyst is free of Ce. The catalyst of any of embodiments 1 to 14, wherein the substrate is a wall-flow substrate or a flow-through substrate, preferably a honeycomb wall-flow substrate or a honeycomb flow-through substrate, more preferably a honeycomb flow-through substrate, wherein the flow-through substrate is more preferably a flow-through substrate with high porosity walls. The catalyst of any of embodiments 1 to 15, wherein the loading of the first washcoat layer is in the range of from 0.5 to 5 g / in3, preferably of from 1 to 3 g / in3, more preferably of from 1 .5 to 2.5 g / in3, more preferably of from 1 .8 to 2 g / in3. The catalyst of any of embodiments 1 to 16, wherein the loading of the second washcoat layer is in the range of from 0.25 to 6 g / in3, preferably of from 0.5 to 6 g / in3, more preferably of from 1 to 5 g / in3, more preferably of from 1.5 to 4.5 g / in3, more preferably of from 2 to 4 g / in3, more preferably of from 2.2 to 3.5 g / in3, more preferably of from 2.5 to 3.2 g / in3, more preferably of from 2.8 to 3.0 g / in3. The catalyst of any of embodiments 1 to 17, wherein the catalyst comprises one or more platinum group metals consisting of Pt, Pd, or Pt and Pd, wherein preferably the catalyst comprises Pt, or Pt and Pd as the one or more platinum group metals, wherein more preferably the catalyst comprises Pt and Pd as the one or more platinum group metals. The catalyst of any of embodiments 1 to 18, wherein the catalyst comprises Pt, calculated as the element, at a loading in the range of from 2 to 250 g / ft3, preferably of from 5 to 150 g / ft3, more preferably of from 10 to 125 g / ft3, more preferably of from 20 to 100 g / ft3, more preferably of from 25 to 85 g / ft3, more preferably of from 30 to 80 g / ft3, more preferably of from 40 to 60 g / ft3. The catalyst of any of embodiments 1 to 19, wherein the catalyst comprises Pd, calculated as the element, at a loading in the range of from 1 to 80 g / ft3, preferably of from 5 to 60 g / ft3, more preferably of from 10 to 50 g / ft3, more preferably of from 15 to 40 g / ft3, more preferably of from 20 to 30 g / ft3. The catalyst of any of embodiments 1 to 20, wherein the catalyst comprises Pt and Pd, calculated as the respective element, at a total Pt and Pd loading in the range of from 2 to 250 g / ft3, preferably of from 5 to 200 g / ft3, more preferably of from 10 to 150 g / ft3, more preferably of from 20 to 130 g / ft3, more preferably of from 30 to 125 g / ft3, more preferably of from 40 to 110 g / ft3, more preferably of from 50 to 100 g / ft3, more preferably of from 60 to 90 g / ft3, more preferably of from 70 to 80 g / ft3. The catalyst of any of embodiments 1 to 21 , wherein the catalyst comprises Pt and Pd at a Pt : Pd weight ratio in the range of from 30:70 to 90:10, preferably of from 50:50 to 80:20, more preferably of from 60:40 to 75:25, more preferably of from 65:35 to 70:30. The catalyst of any of embodiments 1 to 22, wherein at least part of the one or more platinum group metals are supported on a particulate support material, wherein the particulate support material is preferably selected from the group consisting of AI2O3, SiC>2, TiC>2, SiC>2-doped AI2O3, Mn oxide-doped AI2O3, and mixtures of two or more thereof, wherein preferably the one or more platinum group metals are supported on AI2O3 and / or SiC>2- doped AI2O3 and / or Mn oxide-doped AI2O3, more preferably SiC>2-doped AI2O3 or AI2O3 or Mn oxide-doped AI2O3, more preferably SiC>2-doped AI2O3 or AI2O3, wherein more preferably at least part of the one or more platinum group metals are supported on SiC>2-doped AI2O3.

[0147] 24. The catalyst of embodiment 23, wherein the Mn oxide-doped AI2O3 comprises from 1 to 10 weight-%, preferably from 4 to 6 weight-%, of Mn oxide, calculated as MnC>2, based on 100 weight-% of the Mn oxide-doped AI2O3.

[0148] 25. The catalyst of embodiment 23, wherein the SiC>2-doped AI2O3 comprises from 1 to 10 weight-%, preferably from 4 to 6 weight-%, of SiC>2 based on 100 weight-% of the SiC>2- doped AI2O3.

[0149] 26. The catalyst of any of embodiments 1 to 25, wherein the catalyst further comprises a hydrocarbon trap material, wherein the hydrocarbon trap material is at least in part contained in one or more of:

[0150] (a) the first washcoat layer, and

[0151] (b) an optional second washcoat layer, or

[0152] (c) optional second and third washcoat layers.

[0153] 27. The catalyst of embodiment 26, wherein the hydrocarbon trap material comprises a molecular sieve, preferably a zeolite, more preferably a zeolite having a maximum pore size of 12-membered rings, more preferably zeolite beta.

[0154] 28. The catalyst of embodiment 27, wherein the molecular sieve, preferably the framework of the zeolite, comprises SiC>2 and AI2O3.

[0155] 29. The catalyst of embodiment 27 or 28, wherein the molecular sieve, preferably the zeolite, has a molar ratio of SiC>2 to AI2O3 in the range of from 10:1 to 500:1 , more preferably of from 10:1 to 100:1 , more preferably of from 10:1 to 40:1 , more preferably of from 15:1 to 30:1 , more preferably of from 20:1 to 25:1.

[0156] 30. The catalyst of any of embodiments 27 to 29, wherein the molecular sieve, preferably the zeolite, comprises Fe, wherein the molecular sieve, preferably the zeolite, preferably comprises Fe, calculated as Fe2Os, in an amount in the range of from 1 .0 to 7.0 weight-%, more preferably of from 3.0 to 5.0 weight-%, more preferably of from 4.0 to 4.5 weight-%, based on the weight of the molecular sieve. The catalyst of any of embodiments 26 to 30, wherein the loading of the hydrocarbon trap material in the first washcoat layer and / or in each of the respective optional second or second and third washcoat layers is in the range of from 0.01 to 5.0 g / in3, preferably in the range of from 0.05 to 3.0 g / in3, more preferably in the range of from 0.1 to 2.0 g / in3, more preferably in the range of from 0.15 to 1.0 g / in3, more preferably in the range of from 0.2 to 0.5 g / in3, more preferably in the range of from 0.22 to 0.3 g / in3, more preferably in the range of from 0.25 to 0.27 g / in3. The catalyst of any of embodiments 26 to 31 , wherein the catalyst comprises a second washcoat layer, wherein the hydrocarbon trap material is at least in part contained in the second washcoat layer. The catalyst of any of embodiments 26 to 32, wherein the catalyst comprises a third washcoat layer, wherein the hydrocarbon trap material is at least in part contained in the third washcoat layer. The catalyst of embodiment 33, wherein the catalyst comprises second and third washcoat layers, wherein the hydrocarbon trap material is at least in part contained in the second and third washcoat layers. The catalyst of any of embodiments 1 to 34, wherein the catalyst further comprises a sulfur-trap material, wherein the sulfur-trap material is at least in part contained in one or more of:

[0157] (a) the first washcoat layer, and

[0158] (b) an optional second washcoat layer, or

[0159] (c) optional second and third washcoat layers. The catalyst of embodiment 35, wherein the content of the sulfur-trap material independently from one another in the first, second and third washcoat layers is in the range of from 5 to 75 wt.-% based on 100 wt.-% of the respective washcoat layer, preferably from

[0160] 10 to 50 wt.-%, more preferably from 15 to 40 wt.-%, more preferably from 20 to 30 wt.-%. The catalyst of embodiment 35 or 36, wherein the sulfur-trap material comprises one or more metal oxides which react with SO2 and / or SO3 to form corresponding metal sulfites and / or sulfates, wherein preferably the sulfur-trap material consists of the one or more metal oxides. The catalyst of embodiment 37, wherein each of the one or more metal oxides, which react with SO2 and / or SO3 to form corresponding metal sulfite and / or sulfate, displays a desulfation temperature T50, at which 50% of the respective metal sulfite and / or metal sulfate has decomposed to the metal oxide and SO2 and / or SO3, which is lower than the desulfation temperature T50 of MnSC , wherein preferably, each of the one or more metal oxides displays a desulfation temperature T50 which is at least 10°C lower than the desulfation temperature T50 of MnSC , preferably at least 20°C lower, more preferably at least 50°C lower, more preferably at least 80°C lower, more preferably at least 100°C lower, more preferably at least 150°C lower.

[0161] 39. The catalyst of embodiment 37 or 38, wherein the one or more metal oxides are selected from the group consisting of oxides of Cu, Ni, Co, Fe, and Sn, including mixtures of two or more thereof, preferably from the group consisting of oxides of Cu, Fe, and Sn, including mixtures of two or more thereof, wherein more preferably the one or more metal oxides comprise, preferably consist of, oxides of Fe.

[0162] 40. The catalyst of embodiment 39, wherein the one or more metal oxides are selected from the group consisting of Fe20s, CuO, SnO, and SnO2, including mixtures of two or more thereof, wherein more preferably the one or more metal oxides comprise, preferably consist of Fe20s.

[0163] 41 . The catalyst of embodiment 39 or 40, the one or more metal oxides comprise, preferably consist of, oxides of Fe, wherein preferably the one or more metal oxides comprise, preferably consist of, Fe20s and / or Fe2O3-doped AI2O3, more preferably comprise, preferably consist of, Fe20s.

[0164] 42. The catalyst of embodiment 41 , wherein the content of the one or more oxides of Fe independently from one another in the first, second and third washcoat layers, calculated as Fe20s and based on 100 wt.-% of the respective washcoat layer, is in the range of from 1 to 100 wt.-%, preferably from 5 to 75 wt.-%, more preferably from 10 to 50 wt.-%, more preferably from 15 to 40 wt.-%, more preferably from 20 to 30 wt.-%.

[0165] 43. The catalyst of embodiment 41 or 42, wherein the one or more oxides of Fe display an average particle size D50 of 20 pm or less, preferably of 10 pm or less, more preferably of 5 pm or less, more preferably of 1 pm or less, wherein the average particle size is preferably determined according to ISO 13320:2020.

[0166] 44. The catalyst of any of embodiments 41 to 43, wherein the one or more metal oxides of Fe are supported on a particulate support material, wherein the particulate support material is preferably selected from the group consisting of ZrO2, AI2O3, SiO2, SiO2-AhO3, TiO2, La2O3-doped ZrO2, CeO2-ZrO2 mixed oxide, La2O3-doped CeO2-ZrO2 mixed oxide, Nd20s- doped CeO2-ZrC>2 mixed oxide, Y2Os-doped CeO2-ZrO2 mixed oxide, praseodymium ox- ide-doped CeO2-ZrC>2 mixed oxide, ZrC>2-doped AI2O3, ZrC>2-doped SiC>2, SiC>2-doped AI2O3, CUO-AI2O3 mixed oxide, and mixtures of two or more thereof, more preferably from the group consisting of AI2O3, SiC>2, SiC^-AhOs, La2C>3-doped ZrC>2, CeO2-ZrO2 mixed oxide, La2C>3-doped CeO2-ZrO2 mixed oxide, and mixtures of two or more thereof, more preferably from the group consisting of AI2O3, SiO2-AhO3, La2C>3-doped ZrC>2, CeO2-ZrO2 mixed oxide, and mixtures of two or more thereof, wherein more preferably Fe is supported on particulate La2C>3-doped ZrC>2.

[0167] 45. The catalyst of embodiment 39, wherein the one or more metal oxides comprise, preferably consist of, oxides of Sn, preferably of SnO, SnC>2, or SnO and SnC>2.

[0168] 46. The catalyst of embodiment 45, wherein the oxides of Sn are supported on a particulate support material, wherein the particulate support material is preferably selected from the group consisting of ZrC>2, AI2O3, SiC>2, SiO2-AhO3, TiC>2, La2O3-doped ZrC>2, CeO2-ZrO2 mixed oxide, La2C>3-doped CeO2-ZrO2 mixed oxide, Nd2Os-doped CeO2-ZrO2 mixed oxide, Y2C>3-doped CeO2-ZrO2 mixed oxide, praseodymium oxide-doped CeO2-ZrO2 mixed oxide, ZrC>2-doped AI2O3, ZrC>2-doped SiC>2, SiC>2-doped AI2O3, CUO-AI2O3 mixed oxide, and mixtures of two or more thereof, more preferably from the group consisting of AI2O3, SiC>2, SiO2-AhO3, La2C>3-doped ZrC>2, CeO2-ZrO2 mixed oxide, La2C>3-doped CeO2-ZrO2 mixed oxide, and mixtures of two or more thereof, more preferably from the group consisting of AI2O3, SiO2-AhO3, La2C>3-doped ZrC>2, CeO2-ZrO2 mixed oxide, and mixtures of two or more thereof, wherein more preferably Sn is supported on particulate La2C>3-doped ZrC>2.

[0169] 47. The catalyst of any of embodiments 1 to 46, wherein the catalyst comprises a second washcoat layer, wherein the one or more platinum group metals are at least in part contained in the second washcoat layer, wherein preferably the one or more platinum group metals are entirely contained in the second washcoat layer.

[0170] 48. The catalyst of any of embodiments 1 to 47, wherein the catalyst comprises a second washcoat layer, wherein the catalyst displays a layered arrangement of the first and second washcoat layers, and wherein the one or more platinum group metals are at least in part contained in the second washcoat layer.

[0171] 49. The catalyst of embodiment 48, wherein the first washcoat layer is provided on the substrate, and the second washcoat layer is provided on the first washcoat layer.

[0172] 50. The catalyst of embodiment 47 or 48, wherein the second washcoat layer is provided on the substrate, and the first washcoat layer is provided on the second washcoat layer. The catalyst of embodiment 48 or 49, wherein the catalyst comprises a third washcoat layer, wherein the catalyst displays a zoned arrangement of the first, second, and third washcoat layers, wherein the third washcoat layer is provided on the substrate along its axial length starting from the inlet end of the substrate and wherein the first washcoat layer is provided on the substrate along its axial length starting from the outlet end of the substrate, and wherein the second washcoat layer is provided on and entirely covers the first washcoat layer, wherein the length of the first washcoat layer is less than the axial length of the substrate such as to create an upstream zone comprising the third washcoat layer and a downstream zone comprising the first and second washcoat layers, and wherein the one or more platinum group metals are at least in part contained in the third washcoat layer. The catalyst of embodiment 48 or 50, wherein the catalyst comprises a third washcoat layer, wherein the catalyst displays a zoned arrangement of the first, second, and third washcoat layers, wherein the third washcoat layer is provided on the substrate along its axial length starting from the inlet end of the substrate and wherein the second washcoat layer is provided on the substrate along its axial length starting from the outlet end of the substrate, and wherein the first washcoat layer is provided on and entirely covers the second washcoat layer, wherein the length of the second washcoat layer is less than the axial length of the substrate such as to create an upstream zone comprising the third washcoat layer and a downstream zone comprising the first and second washcoat layers, and wherein the one or more platinum group metals are at least in part contained in the third washcoat layer. The catalyst of embodiment 48 or 49, wherein the catalyst comprises a third washcoat layer, wherein the catalyst displays a zoned arrangement of the first, second, and third washcoat layers, wherein the third washcoat layer is provided on the substrate along its axial length starting from the outlet end of the substrate and wherein the first washcoat layer is provided on the substrate along its axial length starting from the inlet end of the substrate, and wherein the second washcoat layer is provided on and entirely covers the first washcoat layer, wherein the length of the first washcoat layer is less than the axial length of the substrate such as to create a downstream zone comprising the third washcoat layer and an upstream zone comprising the first and second washcoat layers, and wherein the one or more platinum group metals are at least in part contained in the third washcoat layer. The catalyst of embodiment 48 or 50, wherein the catalyst comprises a third washcoat layer, wherein the catalyst displays a zoned arrangement of the first, second, and third washcoat layers, wherein the third washcoat layer is provided on the substrate along its axial length starting from the outlet end of the substrate and wherein the second washcoat layer is provided on the substrate along its axial length starting from the inlet end of the substrate, and wherein the first washcoat layer is provided on and entirely covers the second washcoat layer, wherein the length of the second washcoat layer is less than the axial length of the substrate such as to create a downstream zone comprising the third washcoat layer and an upstream zone comprising the first and second washcoat layers, and wherein the one or more platinum group metals are at least in part contained in the third washcoat layer.

[0173] 55. The catalyst of any of embodiments 1 to 47, wherein the catalyst comprises a second washcoat layer, wherein the catalyst displays a zoned arrangement of the first and second washcoat layers, wherein the second washcoat layer is provided on the substrate along its axial length starting from the inlet end of the substrate, and wherein the first washcoat layer is provided on the substrate along its axial length starting from the outlet end of the substrate, wherein the length of the first washcoat layer is less than the axial length of the substrate such as to create an upstream zone comprising the second washcoat layer and a downstream zone comprising the first washcoat layer, and wherein the one or more platinum group metals are at least in part contained in the second washcoat layer.

[0174] 56. The catalyst of any of embodiments 1 to 47, wherein the catalyst comprises a second washcoat layer, wherein the catalyst displays a zoned arrangement of the first and second washcoat layers, wherein the first washcoat layer is provided on the substrate along its axial length starting from the inlet end of the substrate, and wherein the second washcoat layer is provided on the substrate along its axial length starting from the outlet end of the substrate, wherein the length of the first washcoat layer is less than the axial length of the substrate such as to create an upstream zone comprising the first washcoat layer and a downstream zone comprising the second washcoat layer, and wherein the one or more platinum group metals are at least in part contained in the second washcoat layer.

[0175] 57. The catalyst of any of embodiments 1 to 47, wherein the catalyst comprises a second washcoat layer, wherein the catalyst displays a zoned arrangement of the first and second washcoat layers, wherein the second washcoat layer is provided on the substrate along its axial length starting from the inlet end of the substrate, and wherein the first washcoat layer is provided on the substrate along its axial length starting from the outlet end of the substrate, wherein the length of the second washcoat layer is less than the axial length of the substrate such as to create an upstream zone comprising the second washcoat layer and a downstream zone comprising the first washcoat layer, and wherein the one or more platinum group metals are at least in part contained in the second washcoat layer.

[0176] 58. The catalyst of any of embodiments 1 to 47, wherein the catalyst comprises a second washcoat layer, wherein the catalyst displays a zoned arrangement of the first and second washcoat layers, wherein the first washcoat layer is provided on the substrate along its axial length starting from the inlet end of the substrate, and wherein the second washcoat layer is provided on the substrate along its axial length starting from the outlet end of the substrate, wherein the length of the second washcoat layer is less than the axial length of the substrate such as to create an upstream zone comprising the first washcoat layer and a downstream zone comprising the second washcoat layer, and wherein the one or more platinum group metals are at least in part contained in the second washcoat layer. The catalyst of embodiment 55 or 57, wherein the catalyst comprises a third washcoat layer, wherein the third washcoat layer is provided on the first washcoat layer, wherein the catalyst displays a zoned arrangement of the second and third washcoat layers, wherein the second washcoat layer is provided on the substrate along the axial length of the substrate starting from the inlet end of the substrate, and wherein the third washcoat layer is provided on the first washcoat layer along the axial length of the substrate starting from the outlet end of the substrate, wherein the length of the third washcoat layer is less than the axial length of the substrate such as to create an upstream zone comprising the second washcoat layer and a downstream zone comprising the first and third washcoat layers. The catalyst of embodiment 56 or 58, wherein the catalyst comprises a third washcoat layer, wherein the third washcoat layer is provided on the first washcoat layer, wherein the catalyst displays a zoned arrangement of the second and third washcoat layers, wherein the third washcoat layer is provided on the first washcoat layer along the axial length of the substrate starting from the inlet end of the substrate, and wherein the second washcoat layer is provided on the substrate along the axial length of the substrate starting from the outlet end of the substrate, wherein the length of the third washcoat layer is less than the axial length of the substrate such as to create an upstream zone comprising the first and third washcoat layers and a downstream zone comprising the second washcoat layer. The catalyst of any of embodiments 55 to 60, wherein the first and second washcoat layers are adjacent to one another. The catalyst of any of embodiments 51 to 54, wherein the first and third washcoat layers are adjacent to one another. The catalyst of any of embodiments 51 to 54 and 59 to 60, wherein the second and third washcoat layers are adjacent to one another. The catalyst of any of embodiments 55 to 60, wherein a portion of the second washcoat layer overlaps at least a portion of the first washcoat layer, wherein preferably the second washcoat layer overlaps the first washcoat layer over a portion ranging from 10 to 100% of the axial length of the first washcoat layer, more preferably from 15 to 80%, more preferably from 20 to 50%. The catalyst of any of embodiments 55 to 60, wherein a portion of the first washcoat layer overlaps at least a portion of the second washcoat layer, wherein preferably the first washcoat layer overlaps the second washcoat layer over a portion ranging from 10 to 100% of the axial length of the second washcoat layer, more preferably from 15 to 80%, more preferably from 20 to 50%. The catalyst of any of embodiments 51 to 54 and 59 to 61 and 63 to 65, wherein a portion of the third washcoat layer overlaps at least a portion of the first washcoat layer, wherein preferably the third washcoat layer overlaps the first washcoat layer over a portion ranging from 10 to 100% of the axial length of the first washcoat layer, more preferably from 15 to 80%, more preferably from 20 to 50%. The catalyst of any of embodiments 1 to 47, wherein the catalyst comprises a second washcoat layer, wherein the catalyst displays a zoned arrangement of the first and second washcoat layers, wherein the second washcoat layer is provided on the substrate along its entire length, and wherein the first washcoat layer is provided on the second washcoat layer along its axial length starting from the outlet end of the substrate, wherein the length of the first washcoat layer is less than the axial length of the substrate such as to create an upstream zone comprising the second washcoat layer and a downstream zone comprising the first washcoat layer, and wherein the one or more platinum group metals are at least in part contained in the second washcoat layer. The catalyst of any of embodiments 1 to 47, wherein the catalyst comprises a second washcoat layer, wherein the catalyst displays a zoned arrangement of the first and second washcoat layers, wherein the second washcoat layer is provided on the substrate along its entire length, and wherein the first washcoat layer is provided on the second washcoat layer along its axial length starting from the inlet end of the substrate, wherein the length of the first washcoat layer is less than the axial length of the substrate such as to create an upstream zone comprising the first washcoat layer and a downstream zone comprising the second washcoat layer, and wherein the one or more platinum group metals are at least in part contained in the second washcoat layer. The catalyst of embodiment 67 or 68, wherein the length of the first washcoat layer ranges from 10 to 90% of the axial length of the substrate, preferably from 30 to 80%, more preferably from 50 to 70%. 70. The catalyst of any of embodiments 1 to 47, wherein the catalyst comprises a second washcoat layer, wherein the catalyst displays a zoned arrangement of the first and second washcoat layers, wherein the first washcoat layer is provided on the substrate along its entire length, and wherein the second washcoat layer is provided on the first washcoat layer along its axial length starting from the inlet end of the substrate, wherein the length of the second washcoat layer is less than the axial length of the substrate such as to create an upstream zone comprising the second washcoat layer and a downstream zone comprising the first washcoat layer, and wherein the one or more platinum group metals are at least in part contained in the second washcoat layer.

[0177] 71 . The catalyst of embodiment 70, wherein the catalyst comprises a third washcoat layer, wherein the third washcoat layer is provided on the first washcoat layer, wherein the catalyst displays a zoned arrangement of the second and third washcoat layers, wherein the second washcoat layer is provided on the first washcoat layer along the axial length of the substrate starting from the inlet end of the substrate, and wherein the third washcoat layer is provided on the first washcoat layer along the axial length of the substrate starting from the outlet end of the substrate, wherein the length of the third washcoat layer is less than the axial length of the substrate such as to create an upstream zone comprising the second washcoat layer and a downstream zone comprising the third washcoat layer.

[0178] 72. The catalyst of any of embodiments 1 to 47, wherein the catalyst comprises a second washcoat layer, wherein the catalyst displays a zoned arrangement of the first and second washcoat layers, wherein the first washcoat layer is provided on the substrate along its entire length, and wherein the second washcoat layer is provided on the first washcoat layer along its axial length starting from the outlet end of the substrate, wherein the length of the second washcoat layer is less than the axial length of the substrate such as to create an upstream zone comprising the first washcoat layer and a downstream zone comprising the second washcoat layer, and wherein the one or more platinum group metals are at least in part contained in the second washcoat layer.

[0179] 73. The catalyst of embodiment 72, wherein the catalyst comprises a third washcoat layer, wherein the third washcoat layer is provided on the first washcoat layer, wherein the catalyst displays a zoned arrangement of the second and third washcoat layers, wherein the third washcoat layer is provided on the first washcoat layer along the axial length of the substrate starting from the inlet end of the substrate, and wherein the second washcoat layer is provided on the first washcoat layer along the axial length of the substrate starting from the outlet end of the substrate, wherein the length of the third washcoat layer is less than the axial length of the substrate such as to create an upstream zone comprising the third washcoat layer and a downstream zone comprising the second washcoat layer. 74. The catalyst of embodiment 71 or 73, wherein the second and third washcoat layers are adjacent to one another.

[0180] 75. The catalyst of any one of embodiments 1 to 48, wherein the first washcoat layer is provided on the substrate, wherein the second washcoat layer is at least partially, preferably completely, provided on the first washcoat layer, and wherein the third washcoat layer is at least partially, preferably completely, provided on the second washcoat layer.

[0181] 76. The catalyst of any one of embodiments 1 to 48, wherein the first washcoat layer is provided on the substrate, wherein the third washcoat layer is at least partially, preferably completely, provided on the first washcoat layer, and wherein the second washcoat layer is at least partially, preferably completely, provided on the third washcoat layer.

[0182] 77. The catalyst of any of embodiments 1 to 76, wherein the length of the first washcoat layer ranges from 5 to 100% of the axial length of the substrate, preferably from 10 to 90% of the axial length of the substrate, preferably from 15 to 75%, more preferably from 20 to 60%, more preferably from 25 to 50%, more preferably from 35 to 45%.

[0183] 78. The catalyst of any of embodiment 47 to 77, wherein the length of the second washcoat layer ranges from 5 to 100% of the axial length of the substrate, preferably from 10 to 90% of the axial length of the substrate, more preferably from 15 to 75%, more preferably from 20 to 60%, more preferably from 25 to 50%, more preferably from 35 to 45%.

[0184] 79. The catalyst of any of embodiment 51 to 54 and 59 to 60 and 62 to 63 and 71 and 73, wherein the length of the third washcoat layer ranges from 5 to 100% of the axial length of the substrate, preferably from 10 to 90% of the axial length of the substrate, preferably from 15 to 75%, more preferably from 20 to 60%, more preferably from 25 to 50%, more preferably from 35 to 45%.

[0185] 80. The catalyst of any of embodiments 1 to 79, preferably of any of embodiments 51 to 79, wherein the one or more platinum group metals are at least in part contained in the third washcoat layer.

[0186] 81 . The catalyst of any of embodiments 1 to 79, preferably of any of embodiments 51 to 79, wherein the catalyst comprises second and third washcoat layers, wherein the one or more platinum group metals are entirely contained in the second and third washcoat layers.

[0187] 82. The catalyst of embodiment 81 , wherein the weight ratio of the one or more platinum group metals comprised in the second washcoat layer to the one or more platinum group metals comprised in the third washcoat layer is in the range of from 0.5:1 to 5.0:1 , more preferably 1.0:1 to 2.0:1 , more preferably in the range of from 1.4:1 to 1.6:1 , wherein the one or more platinum group metals comprised in the second washcoat layer preferably comprise, more preferably consist of, Pt and Pd, wherein the one or more platinum group metals comprised in the third washcoat layer preferably comprise, more preferably consist of, Pt and Pd.

[0188] 83. The catalyst of any of embodiments 1 to 82, wherein the substrate is a metallic substrate or a ceramic substrate, wherein preferably the substrate is a ceramic substrate, wherein more preferably the substrate comprises cordierite and / or SiC, preferably cordierite, wherein more preferably, the substrate consists cordierite and / or SiC, preferably of cordierite.

[0189] 84. The catalyst of any of embodiments 51 to 83, wherein the substrate consists of two separate monoliths, wherein the first monolith is provided upstream of the second monolith, wherein the washcoat layer or washcoat layers of the upstream zone are contained on the first monolith, and the washcoat layer or washcoat layers of the downstream zone are contained on the second monolith, wherein preferably the first monolith containing the washcoat layer or washcoat layers of the upstream zone and the second monolith containing the washcoat layer or washcoat layers of the downstream zone are obtained or obtainable by sectioning of a catalyst according to any of embodiments 51 to 83 into two separate monoliths, wherein the washcoat layer or washcoat layers of the upstream zone are contained on the first monolith, and the washcoat layer or washcoat layers of the downstream zone are contained on the second monolith.

[0190] 85. The catalyst of any of embodiments 1 to 84, wherein the exhaust gas stream contains hydrocarbons, preferably C1 to C20 hydrocarbons, more preferably C2 to C10 hydrocarbons.

[0191] 86. Exhaust gas treatment system comprising an internal combustion engine and an exhaust gas conduit for exhaust gas from the internal combustion engine, wherein the exhaust gas conduit comprises one or more catalysts according to any of embodiments 1 to 85, preferably one, two, three or four catalysts according to any of embodiments 1 to 85.

[0192] 87. The exhaust gas treatment system of embodiment 86, wherein the internal combustion engine is a compression ignition engine, preferably a diesel engine.

[0193] 88. The exhaust gas treatment system of embodiment 86 or 87, wherein the internal combustion engine is a lean gasoline engine. The exhaust gas treatment system of embodiment 86, wherein the internal combustion engine is powered by an oxygenated fuel, wherein the oxygenated fuel preferably comprises one or more of methanol and biofuel. The exhaust gas treatment system of any of embodiments 86 to 89, wherein the system comprises one or more of an electric heater, a fuel burner, a fuel injector, a selective catalytic reduction (SCR) catalyst, an ammonia oxidation (AMOX) catalyst, a catalyzed soot filter (CSF), a diesel particulate filter (DPF), a selective catalytic reduction catalyst on filter (SCRoF), and a diesel exotherm catalyst (DEC). The exhaust gas treatment system of embodiment 90, comprising in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a catalyst according to any of embodiments 1 to 85, a catalyst according to any of embodiments 1 to 85, a selective catalytic reduction (SCR) catalyst, a selective catalytic reduction (SCR) catalyst, an optional fuel injector, a diesel exotherm catalyst (DEC), a catalyzed soot filter (CSF), a selective catalytic reduction (SCR) catalyst, and a selective catalytic reduction (SCR) catalyst. The exhaust gas treatment system of embodiment 90, comprising in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a catalyst according to any of embodiments 1 to 85, a catalyst according to any of embodiments 1 to 85, a selective catalytic reduction (SCR) catalyst, a selective catalytic reduction (SCR) catalyst, an optional fuel injector, a diesel exotherm catalyst (DEC), a diesel particulate filter (DPF), a selective catalytic reduction (SCR) catalyst, and a selective catalytic reduction (SCR) catalyst. The exhaust gas treatment system of embodiment 90, comprising in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a catalyst according to any of embodiments 1 to 85, a catalyst according to any of embodiments 1 to 85, a selective catalytic reduction (SCR) catalyst, a selective catalytic reduction (SCR) catalyst, an optional fuel injector, a diesel exotherm catalyst (DEC), a diesel particulate filter (DPF), a selective catalytic reduction (SCR) catalyst, and an ammonia oxidation (AMOX) catalyst. The exhaust gas treatment system of embodiment 90, comprising in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a catalyst according to any of embodiments 1 to 85, a catalyst according to any of embodiments 1 to 85, a selective catalytic reduction (SCR) catalyst, a selective catalytic reduction (SCR) catalyst, an optional fuel injector, a catalyst according to any of embodiments 1 to 85, a diesel particulate filter (DPF), a selective catalytic reduction (SCR) catalyst, and a selective catalytic reduction (SCR) catalyst. 95. The exhaust gas treatment system of embodiment 90, comprising in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a catalyst according to any of embodiments 1 to 85, a catalyst according to any of embodiments 1 to 85, a selective catalytic reduction (SCR) catalyst, a selective catalytic reduction (SCR) catalyst, an optional fuel injector, a catalyst according to any of embodiments 1 to 85, a catalyst according to any of embodiments 1 to 85, wherein the substrate is a wall-flow substrate, a selective catalytic reduction (SCR) catalyst, and an ammonia oxidation (AMOX) catalyst.

[0194] 96. The exhaust gas treatment system of embodiment 90, comprising in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a catalyst according to any of embodiments 1 to 85, a selective catalytic reduction (SCR) catalyst, a selective catalytic reduction (SCR) catalyst, a catalyzed soot filter (CSF), a selective catalytic reduction (SCR) catalyst, and a selective catalytic reduction (SCR) catalyst.

[0195] 97. The exhaust gas treatment system of embodiment 90, comprising in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a catalyst according to any of embodiments 1 to 85, a selective catalytic reduction (SCR) catalyst, a selective catalytic reduction (SCR) catalyst, a catalyzed soot filter (CSF), a selective catalytic reduction (SCR) catalyst, and an ammonia oxidation (AMOX) catalyst.

[0196] 98. The exhaust gas treatment system of embodiment 90, comprising in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a catalyst according to any of embodiments 1 to 85, a selective catalytic reduction (SCR) catalyst, a selective catalytic reduction (SCR) catalyst, an optional fuel injector, a catalyst according to any of embodiments 1 to 85, wherein the substrate is a wall-flow substrate, a selective catalytic reduction (SCR) catalyst, and an ammonia oxidation (AMOX) catalyst.

[0197] 99. The exhaust gas treatment system of embodiment 90, comprising in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a catalyst according to any of embodiments 1 to 85, a selective catalytic reduction (SCR) catalyst, a selective catalytic reduction catalyst on filter (SCRoF), and an ammonia oxidation (AMOX) catalyst.

[0198] 100. The exhaust gas treatment system of embodiment 90, comprising in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a selective catalytic reduction (SCR) catalyst, an optional fuel injector, a catalyst according to any of embodiments 1 to 85, a selective catalytic reduction catalyst on filter (SCRoF), and an ammonia oxidation (AMOX) catalyst. The exhaust gas treatment system of embodiment 90, comprising in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a selective catalytic reduction (SCR) catalyst, an optional fuel injector, a catalyst according to any of embodiments 1 to 85, a catalyzed soot filter (CSF), a selective catalytic reduction (SCR) catalyst, and an ammonia oxidation (AMOX) catalyst. The exhaust gas treatment system of embodiment 90, comprising in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a selective catalytic reduction (SCR) catalyst, an optional fuel injector, a catalyst according to any of embodiments 1 to 85, a catalyst according to any of embodiments 1 to 85, wherein the substrate is a wall-flow substrate, a selective catalytic reduction (SCR) catalyst, and an ammonia oxidation (AMOX) catalyst. The exhaust gas treatment system of embodiment 90, comprising in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a catalyst according to any of embodiments 1 to 85, a diesel particulate filter (DPF), a selective catalytic reduction (SCR) catalyst, a selective catalytic reduction (SCR) catalyst, a selective catalytic reduction (SCR) catalyst, a selective catalytic reduction (SCR) catalyst, and an ammonia oxidation (AMOX) catalyst. The exhaust gas treatment system of embodiment 90, comprising in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a catalyst according to any of embodiments 1 to 85, a selective catalytic reduction catalyst on filter (SCRoF), a selective catalytic reduction (SCR) catalyst, and an ammonia oxidation (AMOX) catalyst. The exhaust gas treatment system of embodiment 90, comprising in consecutive order in the direction of the exhaust gas: optionally an electric heater or a fuel burner and / or a fuel injector, a catalyst according to any of embodiments 1 to 85, a selective catalytic reduction (SCR) catalyst, a selective catalytic reduction catalyst on filter (SCRoF), a selective catalytic reduction (SCR) catalyst, and an ammonia oxidation (AMOX) catalyst. Method for the treatment of an exhaust gas stream containing one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons, the method comprising

[0199] (A) providing an exhaust gas stream comprising one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons;

[0200] (B) directing the exhaust gas stream provided in (A) through a catalyst according to any of embodiments 1 to 85. 107. The method of embodiment 106, wherein the exhaust gas stream provided in (A) comprises one or more sulfur-containing compounds, preferably SO2 and / or SO3.

[0201] 108. The method of embodiment 106 or 107, wherein the exhaust gas stream provided in (A) comprises NOX.

[0202] 109. The method of any of embodiments 106 to 108, wherein the exhaust gas stream provided in (A) comprises CO.

[0203] 110. The method of any of embodiments 106 to 109, wherein the exhaust gas stream provided in (A) comprises hydrocarbons, preferably C1 to C20 hydrocarbons, more preferably C2 to C10 hydrocarbons.

[0204] 111. Use of a catalyst according to any of embodiments 1 to 85 for the oxidation of one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons, preferably for the oxidation of one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons in an exhaust gas stream, more preferably for the oxidation of one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons in the exhaust gas stream of an internal combustion engine, more preferably for the oxidation of one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons in the exhaust gas stream of a compression ignition engine, more preferably for the oxidation of one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons in the exhaust gas stream of a diesel engine.

[0205] The present invention is further illustrated by the following examples and comparative examples.

[0206] EXPERIMENTAL SECTION

[0207] Example 1 : Preparation of a catalyst for the treatment of an exhaust gas stream containing one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons

[0208] A catalyst was prepared by coating platinum group metal (PGM)-containing front zone and base metal oxide (BMO)-containing rear zone segments separately on 1 ” diameter cordierite honeycomb substrates and then combining the coated cores sequentially for subsequent S aging and testing. The front zone segment was prepared by first combining Pt (using an aqueous solution containing an ammine stabilized hydroxo Pt(IV) complex, said solution having a Pt content in the range of from 10 to 20 weight-%), Pd (using Pd nitrate), Beta zeolite and a commercial alumina support powder comprising 5 wt.-% silica and having a BET surface area of approximately 150 m2 / g and a pore volume of about 0.6 cm3 / g in an aqueous slurry composition using techniques commonly known in the art. After coating the slurry onto a cordierite substrate followed by drying and calcination at 590 °C, a 1 ” diameter by 1 .2” long core was subsequently cut from the monolith to be used as the front zone segment. Pt-Pd weight ratio was 2:1 , and total Pt-Pd loading was 75 g / ft3of monolith volume. The washcoat loading of the PGM-containing layer was 2.9 g / in3, containing about 91 wt.-% alumina and about 9 wt.-% Beta zeolite. The BMO-contain- ing rear zone segment was prepared by first combining a commercial LaSrMnOs powder of nominal composition (Lao.4oSro.6o)o.95Mn03-z, wherein z is in the range of from 0 to 0.5, with a commercial zirconia powder comprising 9 wt.-% La20s and having a BET surface area of approximately 75 m2 / g in equal weight proportions in de-ionized (DI) water. After milling the resulting mixture to a particle size suitable for coating, boehmite alumina binder was added. The resulting slurry was then coated onto a 1 ” diameter by 1 .8” long cordierite substrate which was dried and subsequently calcined at 590 °C for 1 h. The total washcoat loading was 1 .9 g / in3of monolith volume comprising 48.4 % by weight (Lao.4oSro.6o)o.95Mn03-z, wherein z is in the range of from 0 to 0.5, 48.4 % by weight balance La2C>3-stabilized ZrC>2, and 3.2 % by weight alumina binder.

[0209] Example 2: Catalyst aging and catalytic testing

[0210] Sulfur aging (S aging) of the catalyst prepared in Example 1 was accomplished on a lab reactor at 300°C in a feed comprising 15 ppm SO2, 150 ppm NO, 10 % O2 and 5 % H2O. The flow through the catalyst measured as space velocity was 35,000 / h. Exposure time was 88 minutes corresponding to a target S exposure amount of 1 g (S) / L of monolith volume. Desulfation was then accomplished at 750°C under isothermal conditions for 30 minutes in a feed comprising 10 % O2 and 5 % H2O. Flow through the catalyst as measured by space velocity was 32,000 / h.

[0211] After sulfation and desulfation, samples were tested for formaldehyde (HCHO) light-off performance using a feed comprising 180 ppm NO, 1000 ppm CO, 25 ppm HCHO, 100 ppm-C1 from C2H4, 190 ppm-C1 from C10H22, 10 % O2, 10 % H2O and 10 % CO2. The flow through the catalyst as measured by space velocity was 50,000 / h. The sample was placed in the reactor and first equilibrated at 80 °C in flowing air. The formaldehyde-containing feed was then introduced, and temperature ramping initiated to 300 °C at a ramp rate of 15 °C / min. Formaldehyde concentration was monitored by FTIR during the light-off ramp and conversion performance vs. temperature was subsequently calculated from these measurements. After testing the combined front and rear zones of Example 1 , the Pt-Pd front zone was tested by itself to allow an assessment of the impact of the rear zone BMC component on oxidation performance.

[0212] The results after sulfation and 750°C desulfation are shown in Figure 1. Confirming the benefit of the (Lao.4oSro.6o)o.95Mn03-z perovskite material, wherein z is in the range of from 0 to 0.5, formaldehyde oxidation performance was significantly higher for the sample of Example 1 comprising both the Pt-Pd front zone and BMC rear zone relative to the Pt-Pd front zone tested by itself.

[0213] The results for the catalyst of Example 1 compared to testing performed with only the front zone of said example are shown in Figure 1 . Formaldehyde oxidation performance was substantially higher for the sample of Example 1 in accordance with the present invention already starting at comparably low temperatures and displaying said improved performance at higher temperatures up through 300°C. These results clearly demonstrate that including a BMO layer in a catalyst, wherein the BMO layer specifically contains a Mn-perovskite catalyst, affords a highly costefficient catalyst in view of the reduced amount of platinum group metal catalysts which may be employed for achieving a conversion which would be comparable to a catalyst containing higher amounts of platinum group metals, in particular within the entire temperature range starting at 150°C.

[0214] In addition thereto, it has surprisingly been found that the additional use of a BMO layer specifically containing a Mn-perovskite catalyst affords a light-off performance in the low temperature range between 130 and 160°C, whereas the light-off induced by the platinum group containing catalyst is only observed starting at around 160°C. As a result, the catalyst according to the present invention not only affords a catalyst which is highly cost efficient compared to a catalyst according to the state of the art containing on a greater amount of platinum group metals, but furthermore provides a low temperature activity not observed in a platinum group metal containing catalyst according to the state of the art.

[0215] DESCRIPTION OF THE FIGURES

[0216] Figure 1 : shows formaldehyde (HCHO) oxidation performance after sulfation and 750 °C desulfation for the catalyst of Example 1 and the Pt-Pd front zone of Example 1 tested by itself. Both samples comprised a 2:1 Pt-Pd front zone at 75 g / ft3. The rear zone of Example 1 further comprised a 50-50 by weight mixture of (Lao.4oSro.6o)o.95Mn03-z perovskite material, wherein z is in the range of from 0 to 0.5, and 9 wt.-% La2C>3-stabilized ZrC>2.

[0217] CITED LITERATURE

[0218] - WO 2022 / 047132 A1

[0219] - US 10,598,061 B2

[0220] - US 10,392,980 B2

[0221] - US 2018 / 333677 A1

[0222] - US 2018 / 318805 A1

[0223] M. C. Alvarez-Galvan et al. in Applied Catalysis B. 2004, 51 , 83-91

[0224] - US 2010 / 229533 A1

[0225] - US 2017 / 095803 A1

[0226] - US 2010 / 086458 A1

[0227] - US 2018 / 318805 A1

[0228] - US 2023 / 321636 A1

Claims

Claims1 . A catalyst for the treatment of an exhaust gas stream containing one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons, the catalyst comprising a first washcoat layer comprising a perovskite, wherein the perovskite contains Mn , and a substrate, wherein the substrate has an inlet end through which the exhaust gas stream may enter the catalyst, and an outlet end through which the exhaust gas stream may exit the catalyst, wherein the catalyst further comprises one or more platinum group metals comprising Pt, Pd, or Pt and Pd, wherein the one or more platinum group metals are at least in part contained in one or more of:(a) the first washcoat layer, and(b) an optional second washcoat layer, or(c) optional second and third washcoat layers.

2. The catalyst of claim 1 , wherein the Mn-containing perovskite has the formula(AyBl.y)l.xMnO3-z (I) wherein A is a transition metal and B is an alkaline earth metal, wherein y is in the range of from 0 to 1 , wherein x is in the range of from 0 to 0.10, and wherein z is in the range of from 0 to 0.5.

3. The catalyst of claim 2, wherein transition metal A is selected from the group consisting of Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and combinations of two or more thereof.

4. The catalyst of claim 2 or 3, wherein the alkaline earth metal B is selected from the group consisting of Mg, Ca, Sr, Ba, and combinations of two or more thereof.

5. The catalyst of any of claims 1 to 4, wherein the first washcoat layer further comprises a particulate metal oxide.

6. The catalyst of any of claims 1 to 5, wherein the first washcoat layer is substantially free of Ce.

7. The catalyst of any of claims 1 to 6, wherein the catalyst comprises one or more platinum group metals consisting of Pt, Pd, or Pt and Pd.

8. The catalyst of any of claims 1 to 7, wherein at least part of the one or more platinum group metals are supported on a particulate support material.

9. The catalyst of any of claims 1 to 8, wherein the catalyst further comprises a hydrocarbon trap material, wherein the hydrocarbon trap material is at least in part contained in one or more of:(a) the first washcoat layer, and(b) an optional second washcoat layer, or(c) optional second and third washcoat layers.

10. The catalyst of claim 9, wherein the hydrocarbon trap material comprises a molecular sieve.11 . The catalyst of any of claims 1 to 10, wherein the catalyst further comprises a sulfur-trap material, wherein the sulfur-trap material is at least in part contained in one or more of:(a) the first washcoat layer, and(b) an optional second washcoat layer, or(c) optional second and third washcoat layers.

12. The catalyst of any of claims 1 to 11 , wherein the catalyst comprises a second washcoat layer, wherein the one or more platinum group metals are at least in part contained in the second washcoat layer.

13. Exhaust gas treatment system comprising an internal combustion engine and an exhaust gas conduit for exhaust gas from the internal combustion engine, wherein the exhaust gas conduit comprises one or more catalysts according to any of claims 1 to 12.

14. Method for the treatment of an exhaust gas stream containing one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons, the method comprising(A) providing an exhaust gas stream comprising one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons;(B) directing the exhaust gas stream provided in (A) through a catalyst according to any of claims 1 to 12.

15. Use of a catalyst according to any of claims 1 to 12 for the oxidation of one or more of formaldehyde, nitrogen oxide (NO), and hydrocarbons.

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