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.

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.

This exhaust gas purifying catalyst is provided with a substrate 10 and a catalyst layer 20 formed on a surface of the substrate 10. The catalyst layer 20 contains zeolite particles 22 that support a metal, and a rare earth element-containing compound 24 that contains a rare earth element. The rare earth element-containing compound 24 is added in such an amount that the molar ratio of the rare earth element relative to Si contained in the zeolite 22 is 0.001 to 0.014 in terms of oxides.

A pillar shaped honeycomb structure, including: an outer peripheral wall; and a porous partition wall disposed inside the outer peripheral wall, the a porous partition wall defining a plurality of cells, each of the cells extending from one end face to other end face to form a flow path, wherein a surface of the porous partition wall in the cells comprise a collecting layer having an average pore diameter lower than that of the porous partition wall; and wherein magnetic particles having a Curie point of 700° C. or higher are provided either or both between the surfaces of the porous partition wall and the collecting layer, and on the collecting layer.

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.

The present invention relates to a catalyst for the oxidation of NO, for the oxidation of ammonia and for the selective catalytic reduction of NOx, the catalyst comprising a flow-through substrate, a first coating comprising one or more of a vanadium oxide and a zeolitic material comprising one or more of copper and iron, a second coating comprising a platinum group metal component supported on a non-zeolitic oxidic material and further comprising one or more of a vanadium oxide and a zeolitic material comprising one or more of copper and iron and a third coating comprising a platinum group metal component supported on an oxidic material. The present invention further relates to an exhaust gas treatment system comprising said catalyst.

The present invention provides a tri-metallic layered catalytic article comprising a first layer comprising palladium supported on at least one of an oxygen storage component, and an alumina component; a second layer comprising platinum and rhodium, each supported on at least one of an oxygen storage component and a zirconia component; and a substrate, wherein the weight ratio of palladium to platinum is in the range of 1.0:0.4 to 1:2. The present invention also provides a process for preparing the tri-metallic layered catalytic article, an exhaust system for internal combustion engine and use of the tri-metallic layered catalytic article for purifying a gaseous exhaust stream.

A NO.sub.x adsorber catalyst and its use in an emission treatment system for internal combustion engines, is disclosed. The NO.sub.x adsorber catalyst comprises a first layer consisting essentially of a support material, one or more platinum group metals disposed on the support material, and a NO.sub.x storage material.