The present invention is directed to the purification of exhaust gases of an internal combustion engine operated predominantly with a stoichiometric fuel mixture. The exhaust system has in particular 4 purification functions in a particular order. A three-way catalyst (TWC1) near the engine is followed by a gasoline particle filter (GPF) and another three-way catalyst (TWC2) downstream thereof. The system additionally has a nitrogen oxide storage function.

The invention provides a method for oxidizing chemical, the method having the steps of contacting soot to a catalyst defining a plurality of flat substrates forming a monolith, wherein any one of the substrates has a thickness no greater than 30 nm. Also provided is a catalyst for oxidizing chemical, the catalyst have a morphology having layered plates, wherein any plate is no more than 30 nm thick. The invention also provides a method for producing an oxidation catalyst, the method having the steps of combining a cobalt compound with a potassium compound to create a solution; contacting the solution with a reducing agent for a time and at a temperature sufficient to oxidize the cobalt compound and form a precipitate of the oxidized cobalt compound; filtering the precipitate; and calcining the filtered precipitate.

A diesel soot filter includes a substrate having a surface disposed at least partially within a fluid path of the diesel soot filter. A glass catalyst is disposed on the surface of the substrate such that an exhaust gas contacts at least a portion of a surface of the glass catalyst as the exhaust gas moves within the diesel soot filter. The glass catalyst comprises a plurality of alkali metal ions disposed within the glass catalyst and releasable to the surface of the glass catalyst at a controlled rate and the alkali metal ions combust with the soot as the exhaust gas travels along the fluid path. An oxide basis of the glass catalyst comprises Silicon (Si), Potassium (K), Cesium (Ce), and Zirconium (Zr).

An oxidation catalyst for treating an exhaust gas produced by a compression ignition engine comprising: a substrate; a catalytic material disposed on the substrate, wherein the catalytic material comprises platinum (Pt); and a region comprising a capture material, wherein the capture material comprises a Pt-alloying metal disposed or supported on a refractory oxide, wherein the refractory oxide comprises at least 65% by weight of zirconia, wherein the region is arranged to contact the exhaust gas after the exhaust gas has contacted and/or passed through the catalytic material.

An oxidation catalyst for treating an exhaust gas produced by a stoichiometric natural gas (NG) engine comprising a substrate and a catalytic material for oxidising hydrocarbon (HC), wherein the catalytic material for oxidising hydrocarbon (HC) comprises a molecular sieve and a platinum group metal (PGM) supported on the molecular sieve, wherein the molecular sieve has a framework comprising silicon, oxygen and optionally germanium.

The present disclosure provides catalyst compositions for NOx conversion and catalytic articles incorporating such catalyst compositions. Certain catalyst compositions include a zeolite with a silica-to-alumina ratio from 5 to 20 and sufficient Cu exchanged into cation sites of the zeolite such that the zeolite has a Cu/Al ratio of 0.1 to 0.5 and a CuO loading of 1 to 15 wt. %; and a copper trapping component in a concentration in the range of 1 to 20 wt. %, the copper trapping component including a plurality of particles having a particle size of about 0.5 to 20 microns. Certain catalyst compositions include, as the copper trapping component, alumina present as a plurality of alumina particles with a D.sub.90 particle size distribution in the range of 0.5 microns to 20 microns.

An example of a catalytic converter includes a catalyst to improve low temperature oxidation of carbon monoxide (CO) and hydrocarbons. The catalyst includes a support, which includes a porous alumina structure and a rare earth metal oxide promoter impregnated into pores of the porous alumina structure. The rare earth metal oxide promoter is selected from the group consisting of CeO.sub.2 and CeO.sub.2ZrO.sub.2. A platinum group metal (PGM) is bonded to the support.

A catalytic converter includes a catalyst. The catalyst includes a support, platinum group metal (PGM) particles dispersed on the support, and a barrier formed on the support. The barrier is disposed between a first set of the PGM particles and a second set of the PGM particles to suppress aging of the PGM particles.

An exhaust system 20 for an internal combustion engine comprises a) a first catalysed substrate monolith 12 comprising a first washcoat coating disposed in a first washcoat zone 16 of the substrate monolith and a second washcoat coating disposed in a second washcoat zone 18 of the substrate monolith, wherein the first washcoat coating comprises a catalyst composition comprising at least one platinum group metal (PGM) and at least one support material, wherein at least one PGM in the first washcoat coating is liable to volatilise when the first washcoat coating is exposed to relatively extreme conditions including relatively high temperatures, wherein the second washcoat coating comprises at least one material supporting copper for trapping volatilised PGM and wherein the second washcoat coating is oriented to contact exhaust gas that has contacted the first washcoat; and b) a second catalysed substrate monolith 14 comprising a catalyst for selectively catalysing the reduction of oxides of nitrogen to dinitrogen with a nitrogenous reductant disposed downstream from the first catalysed substrate monolith.

An exhaust after-treatment system for treating an exhaust produced by an engine. The exhaust after-treatment system includes an exhaust passage, a catalytic exhaust after-treatment component in communication with the exhaust passage for treating the exhaust, and a metal hydride module in communication with the exhaust passage that receives a portion of the exhaust therein at a location positioned upstream from the catalytic exhaust after-treatment component. The portion of the exhaust that enters the metal hydride module reacts with a metal hydride contained in the metal hydride module to produce hydrogen gas that facilitates the treating of the exhaust by the catalytic exhaust after-treatment component.