An oxidation catalyst is described for treating an exhaust gas produced by a diesel engine comprising a catalytic region and a substrate, wherein the catalytic region comprises a catalytic material comprising: bismuth (Bi) or an oxide thereof; an alkali metal or an oxide thereof; a platinum group metal (PGM) selected from the group consisting of (i) platinum (Pt), (ii) palladium (Pd) and (iii) platinum (Pt) and palladium (Pd); and a support material comprising a mixed oxide of alumina and silica, a mixed oxide of silica and a refractory oxide, a composite oxide of alumina and silica, a composite oxide of silica and a refractory oxide, alumina doped with a silica or silica doped with a refractory oxide.

The present invention provides catalyst article, and its use in an exhaust system for internal combustion engines, is disclosed. The catalyst article catalyst article comprises: a substrate which is a wall-flow filter having an inlet end and an outlet end and an axial length L therebetween, a plurality of inlet channels extending from the inlet end and a plurality of outlet channels extending from the outlet end, wherein the plurality of inlet channels comprise a first catalyst composition extending from the inlet or outlet end for at least 50% of L and the plurality of outlet channels comprise a second catalyst composition extending from the outlet or inlet end for at least 50% of L, wherein the first and second catalyst compositions overlap by at most 80% of L, and wherein the first and second catalyst compositions each independently comprise a particulate oxygen storage component (OSC) having a first D90 and a particulate inorganic oxide having a second D90 and: i) the first D90 is less than 1 micron and the second D90 is from 1 to 20 microns; or ii) the second D90 is less than 1 micron and the first D90 is from 1 to 20 microns.

An exhaust gas purification apparatus includes a three-way catalyst. The three-way catalyst includes a downstream catalyst layer and an upstream catalyst layer. The downstream catalyst layer is to be provided in an exhaust pipe. The downstream catalyst layer contains a noble metal material containing at least one of Pd, Rh, or Pt, and an OSC material containing at least ceria. The upstream catalyst layer is to be provided in the exhaust pipe closer to an engine than the downstream catalyst layer is. The upstream catalyst layer contains the noble metal material and the OSC material. The upstream catalyst layer contains the ceria at a content less than a content of the ceria in the downstream catalyst layer.

The invention relates to a wall-flow filter as a particle filter with catalytically active coatings in the channels which are closed in a gastight manner at the opposing closed ends of the channels A at the first end, wherein the inlet region of the filter is additionally supplied with a dry powder-gas aerosol which contains metal compounds with a high melting point (such as the metal oxides Al2O3, SiO2, FeO2, TiO2, ZnO2, etc. for example) and which is to simultaneously improve the catalytic activity and the degree of filtration efficiency with respect to the exhaust gas back-pressure.

A catalytic wall-flow monolith filter having three-way catalytic activity for use in an emission treatment system of a positive ignition internal combustion engine comprising a porous filter substrate having a first face and a second face defining a longitudinal direction there between and first and second pluralities of channels extending in the longitudinal direction, wherein the first plurality of channels is open at the first face and closed at the second face and the channels of the first plurality of channels are defined in part by channel wall surfaces, wherein the second plurality of channels is open at the second face and closed at the first face and the channels of the second plurality of channels are defined in part by channel wall surfaces and wherein channel walls between the channel wall surfaces of the first plurality of channels and the channel wall surfaces of the second plurality of channels are porous, wherein a first on-wall coating comprising catalytic material having a layer thickness is present on at least the channel wall surfaces of the first plurality of channels, wherein the catalytic material on channel wall surfaces of the first plurality of channels comprises one or more platinum group metal selected from the group consisting of (i) rhodium (Rh) only; (ii) palladium (Pd) only; (iii) platinum (Pt) and rhodium (Rh); (iv) palladium (Pd) and rhodium (Rh); and (v) platinum (Pt), palladium (Pd) and rhodium (Rh) and a refractory metal oxide support, wherein: (i) an amount by weight of the one or more platinum group metal, per unit volume of the on-wall coating present on channel wall surfaces of the first plurality of channels varies continually along the longitudinal direction; and/or (ii) the layer thickness of the on-wall coating present on channel wall surfaces of the first plurality of channels varies continually along the longitudinal direction.

Methods and systems are provided for emissions control of a vehicle. In one example, an emissions treatment device includes a porous substrate and a catalytic washcoat disposed thereon, the catalytic washcoat having nickel and no other metal. The porous substrate may be configured to filter particulate matter (PM) exiting the vehicle and the catalytic washcoat may be configured to oxidize at least a portion of the PM. The nickel in the catalytic washcoat may provide additional oxygen storage capacity and increased tolerance to sulfur poisoning of catalytic activity of the catalytic washcoat, further promoting PM oxidation. Moreover, because the catalytic washcoat may increase PM oxidation during passive regeneration events, a total number of active regeneration events may be decreased and fuel economy may be maintained.

Methods are provided for emissions control of a vehicle. In one example, a catalyst may include a cerium-based support material and a transition metal catalyst loaded on the support material, the transition metal catalyst including nickel and copper, wherein nickel in the transition metal catalyst is included in a monatomic layer loaded on the support material. In some examples, limiting nickel to the monatomic layer may mitigate extensive transition metal catalyst degradation ascribed to sintering of thicker nickel washcoat layers. Further, by utilizing the cerium-based support material, side reactions involving nickel in the transition metal catalyst with other support materials may be prevented.

The disclosure provides a monolithic wall-flow filter catalytic article including a substrate having an aspect ratio of from about 1 to about 20, and having a functional coating composition disposed on the substrate, the functional coating composition including a first sorbent composition, an oxidation catalyst composition, and optionally, a second sorbent composition. The monolithic wall-flow filter catalytic article may be in a close-coupled position close to the engine. The disclosure further provides an integrated exhaust gas treatment system including the monolithic wall-flow filter catalytic article and may additionally include a flow-through monolith catalytic article. The flow-through monolith catalytic article includes a substrate having a selective catalytic reduction (SCR) coating composition disposed thereon. The integrated exhaust gas treatment system simplifies the traditional four-article system into a two-article Catalyzed Soot Filter (CSF) plus Selective Catalytic Reduction (SCR) CSF+SCR arrangement.

A selective catalytic reduction catalyst for the treatment of an exhaust gas stream of a passive ignition engine, the catalyst comprising a porous wall-flow filter substrate comprising an inlet end, an outlet end, a substrate axial length (w) extending between the inlet end and the outlet end, and a plurality of passages defined by porous internal walls of the porous wall flow filter substrate; wherein the catalyst further comprises a first coating, said first coating extending over x % of the substrate axial length from the inlet end toward the outlet end of the substrate, x being in the range of from 10 to 100, wherein the first coating comprises copper and an 8-membered ring pore zeolitic material; wherein the catalyst further comprises a second coating, the second coating extending over y % of the substrate axial length from the outlet end toward the inlet end of the substrate, y being in the range of from 20 to 90, wherein the second coating comprises copper, and optionally an 8-membered ring pore zeolitic material; wherein the catalyst optionally further comprises a third coating; wherein x+y is at least 90; wherein y % of w from the outlet end toward the inlet end of the substrate define the outlet zone of the coated substrate and (100−y) % of w from the inlet end toward the outlet end of the substrate define the inlet zone of the coated substrate; wherein the ratio of the loading of copper in the inlet zone, Cu(in), calculated as CuO, relative to the loading of copper in the outlet zone, Cu(out), calculated as CuO, Cu(in):Cu(out), is less than 1:1.

The present invention relates to a three-way catalyst (TWC) for treatment of exhaust gases from internal combustion engines operated with a predominantly stoichiometric air/fuel ratio, so called spark ignited engines.