The present invention relates to a honeycomb catalytic converter including: a honeycomb structured body in which multiple through-holes are arranged longitudinally in parallel with one another with a partition wall therebetween; a noble metal supported on the honeycomb structured body; and an inlet-side end face and on outlet-side end face, wherein each partition wall includes a substrate portion in the form of an extrudate containing a ceria-zirconia complex oxide and alumina, and a coat layer formed on a surface of the substrate portion and containing the noble metal, and the inlet-side end face has a higher aperture ratio than the outlet-side end face.

Provided is a catalyst device that makes it possible to efficiently purify exhaust gas. A catalyst device that comprises: a carrier that is formed by stacking and rolling a metal-foil-shaped flat plate and a metal-foil-shaped corrugated plate and that carries a catalyst; and an outer cylinder that houses the carrier and supports the carrier such that one end part of the carrier is oriented toward an exhaust gas upstream side and another end part of the carrier is oriented toward an exhaust gas downstream side. The flat plate and the corrugated plate have a plurality of holes and are covered by a coating film that includes a catalyst substance. The coating film that covers the downstream side of the holes is thicker than the coating film that covers the upstream side of the holes.

A catalyst article and its use in an exhaust system for internal combustion engines is disclosed. The catalyst article comprises a substrate which is a wall-flow filter, a first catalyst composition, and a second catalyst composition. The first and second catalyst compositions each independently comprise an oxygen storage component (OSC) derived from a CeZr mixed oxide sol having a D90 of less than 1.3 micron and a particulate inorganic oxide having a D90 of from 1 to 20 microns.

An exhaust gas purification device includes a substrate including an upstream end and a downstream end and having a length Ls; a first containing Pd particles, extending between the upstream end and a first position, and being in contact with the substrate; a second containing Rh particles, extending between the downstream end and a second position, and being in contact with the substrate; and a third catalyst layer containing Rh particles, extending between the upstream end and a third position, and being in contact with at least the first catalyst layer, wherein an average of a Rh particle size distribution is from 1.0 to 2.0 nm, and a standard deviation of the Rh particle size distribution is 0.8 nm or less in each of the second catalyst layer and the third catalyst layer.

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 oxygen storage capacity (OSC) of the GPF is greater than the OSC of the TWC2, wherein the OSC is determined in mg/l of the volume of the device.

The invention also relates to methods in which the system is used and uses of the system.

A method for purifying the exhaust gas generated by an internal combustion engine, wherein the exhaust gas generated by the internal combustion engine is conducted through an exhaust gas path in which at least one adsorption element is arranged, to which pollutants contained in the exhaust gas at least partly bind, and in which the at least one adsorption element is regenerated by at least partial desorption of the bound pollutants, and pollutants desorbed from the at least one adsorption element during the desorption process are stored in at least one storage unit.

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 GPF is greater than the WCL of the TWC2, 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.

A three-way catalyst article is provided for the treatment of exhaust gas from a positive ignition engine, the catalyst article comprising: a substrate having a first layer provided thereon, wherein a second layer is provided on the first layer, wherein the first layer comprises a first metal and a first alumina, and wherein the second layer comprises a second metal and a second alumina, wherein either (i) the first metal is Pd and the second metal is Rh; or (ii) the first metal is Rh and the second metal is Pd; and wherein at least one of the first and second aluminas comprises theta alumina.

The invention relates to a three-way catalytic converter, which is suitable, in particular, for the removal of carbon monoxide, hydrocarbons and nitrogen oxides out of the exhaust gas of combustion engines operated with stoichiometric air-fuel mixture. The three-way catalytic converter is characterized in that it has a high oxygen storage capacity after aging and consists of at least two catalytically active layers.

The present invention relates to a four-way conversion catalyst for the treatment of an exhaust gas stream of a gasoline engine, the catalyst comprising a porous wall-flow filter substrate comprising an inlet end, an outlet end, a substrate axial length extending between the inlet end and the outlet end, and a plurality of passages defined by porous internal walls of the porous wallflow filter substrate, wherein the plurality of passages comprise inlet passages having an open inlet end and a closed outlet end, and outlet passages having a closed inlet end and an open outlet end, wherein the interface between the passages and the porous internal walls is defined by the surface of the internal walls; wherein the porous internal walls comprise pores which comprise an oxidic component comprising a first refractory metal oxide, said first refractory metal oxide comprising aluminum, said oxidic component having a platinum group metal content in the range of from 0 to 0.001 weight-% based on the total weight of the oxidic component; wherein the catalyst further comprises a first three-way conversion catalytic coating, at least weight-% thereof being comprised in the pores of the internal walls, said first three-way conversion catalytic coating comprising an oxygen storage compound and a platinum group metal supported on a second refractory metal oxide.