A three-way catalyst article, and its use in an exhaust system for internal combustion engines, is disclosed. The catalyst article for treating exhaust gas comprising: a substrate comprising an inlet end, an outlet end with an axial length L; a first catalytic region beginning at the inlet end and extending for less than the axial length L, wherein the first catalytic region comprises a first palladium component; a second catalytic region beginning at the outlet end and extending for less than the axial length L, wherein the second catalytic region comprises a second palladium component; a third catalytic region beginning at the outlet end and extending for less than the axial length L, wherein the third catalytic region comprises a third rhodium component; and wherein the third catalytic region overlies the second catalytic region.

A mixed oxide, a catalytic composition, a catalytic wall-flow monolith, the use of the mixed oxide and the process of the preparation of the mixed oxide. The mixed oxide comprises zirconium, cerium, lanthanum and optionally at least one rare earth element other than cerium and other than lanthanum. The catalytic composition and the wall-flow monolith comprise the particles of the mixed oxide. The use of the mixed oxide is in the preparation of a coating on a filter. The process of preparation of the mixed oxide consists jet milling. The mixed oxide is a compromise between a calibrated size and a low viscosity when in the form of an aqueous slurry while retaining a high specific surface area and a high pore volume.

The present invention provides an exhaust gas purification catalyst including a base material 11 and a catalyst layer 20 provided on the base material 11. The catalyst layer 20 includes: a catalyst metal; and a carrying material 21 carrying the catalyst metal. The carrying material 21 includes: an OSC material 22 having an oxygen storage capacity; and a carrier 23 other than the OSC material. The OSC material 22 has a mean particle diameter Dx of 1.5 μm or more which is larger than the mean particle diameter Dy of the carrier 23 other than the OSC material 22.

An exhaust gas cleaning catalyst is provided with a fire-resistant three-dimensional structural body, a first catalyst layer provide on a first surface side of the fire-resistant three-dimensional structural body, and a second catalyst layer provided on a side of the first catalyst layer opposite to the fire-resistant three-dimensional structural body. The first catalyst layer contains: a complex oxide including cerium and zirconium; and elemental rhodium. The second catalyst layer contains: a complex oxide including cerium and zirconium; and elemental palladium. The amount of cerium included in the second catalyst layer, in terms of cerium dioxide, is 10-25 g per liter of the fire-resistant three-dimensional structural body.

Subject of the invention is an exhaust gas purification system for a gasoline engine, comprising in consecutive order the following devices: a first three-way-catalyst (TWC1), a gasoline particulate filter (GPF) and a second three-way-catalyst (TWC2), wherein the wash coat load (WCL) of the TWC2 is greater than the WCL of the GPF, wherein the WCL is determined in g/l of the volume of the device. The invention also relates to methods in which the system is used and uses of the system.

The presently claimed invention provides an automotive catalyst comprising a platinum group metal selected from palladium, platinum, rhodium and any combination thereof; metal oxide nanoparticles; and a carrier, wherein the platinum group metal and the metal oxide nanoparticles are homogeneously dispersed on the carrier such as alumina component. The metal oxide nanoparticles have a D.sub.90 diameter in the range of 1.0 nm to 50 nm. The presently claimed invention also provides a layered catalytic article comprising catalyst comprising at least one platinum group metal; metal oxide nanoparticles; and a carrier. The presently claimed invention also provides a process for preparing the catalyst and the catalytic article, and a method of treating a gaseous exhaust stream comprising contacting the stream with the catalyst or catalytic article.

A porous composite includes a porous base material, and a porous collection layer provided on a collection surface of the base material (e.g., on inner surfaces of first cells). The collection layer contains catalyst particles of rare-earth oxide or transition-metal oxide situated in pores of the collection surface of the base material. The collection surface has a covered region that is covered with the collection layer and whose total area is 60% or less of the total area of the collection surface.

A method of manufacturing a catalyst article, the method comprising: providing a complex of a polyamine and a PGM; providing a support material; applying the complex to the support material to form a loaded support material; disposing the loaded support material on a substrate; and heating the loaded support material to form nanoparticles of the PGM on the support material.

The invention relates to a catalytic converter for removing carbon monoxide, hydrocarbons and nitrogen oxides from the exhaust gas of internal combustion engines operated with stoichiometric air-fuel mixture, which catalytic converter comprises a substrate of the length L and a catalytic coating, characterized in that the coating is located on the walls of the substrate and extends, proceeding from one end of the substrate, over a length corresponding to at least 50% of L and comprises active aluminum oxide, two cerium/zirconium/rare-earth-metal mixed oxides different from each other, and at least one platinum group metal.

An exhaust gas purification catalyst is provided which can be more enhanced in NOx purification performance. An exhaust gas purification catalyst including a substrate, a NOx storage layer located over the substrate, an oxidation catalyst layer located over a part of the NOx storage layer, the part being located upstream in an exhaust gas flow direction, and a reduction catalyst layer located over a part of the NOx storage layer, the part being located downstream in an exhaust gas flow direction, wherein the NOx storage layer includes an oxidation catalyst including Pd or Pd and Pt, and a NOx storage material including at least one element selected from the group consisting of an alkali metal, an alkali earth metal and a rare-earth element, the oxidation catalyst layer includes an oxidation catalyst including Pt or Pt and Pd, the reduction catalyst layer includes a reduction catalyst including Rh, and a total content rate (mol %) of Pt and Pd based on a total content rate (100 mol %) of metal element(s) in the oxidation catalyst layer is higher than a total content rate (mol %) of Pt and Pd based on a total content rate (100 mol %) of metal elements in the NOx storage layer.