The technology herein disclosed provides a wall flow type exhaust gas purifying catalyst capable of establishing the compatibility between the noxious gas purifying performance and the pressure loss suppressing performance at a high level. The exhaust gas purifying catalyst herein disclosed includes a base material 11 and a catalyst layer 20. Then, a first catalyst region 22 including the catalyst layer 20 formed therein is provided on an entry side surface 16a of a partition wall 16 of the base material 11. A second catalyst region 24 including the catalyst layer 20 formed on a wall surface 18a of a pore 18 is provided in a prescribed region from an exit side surface 16b of the partition wall toward an entry side cell 12. Further, a catalyst unformed region 30 in which a catalyst layer is substantially not formed is provided between the first catalyst region 22 and the second catalyst region 24 in the thickness direction Y of the partition wall 16. As a result of this, it is possible to prevent the deposition of PMs in the second catalyst region 24 including the catalyst layer 20 formed in the pore 18, and to establish the compatibility between the noxious gas purifying performance and the pressure loss suppressing performance at a high level.

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 determining a conversion capability of one or multiple exhaust gas catalytic converters, downstream from an internal combustion engine. The method includes ascertaining a respective local temperature at multiple locations within the one or the multiple catalytic converters, ascertaining a local conversion capability for a section or a partial volume of the one or the multiple catalytic converters based on the local temperature, and ascertaining a global conversion capability of the one or the multiple catalytic converters based on the ascertained local conversion capabilities. A processing unit and a computer program product for carrying out such a method are also described.

When an amount of particulate matter (PM) collected by a gasoline particulate filter (GPF) reaches a predetermined amount, a central processing unit (CPU) executes a regeneration process for regenerating the GPF. That is, the CPU stops supply of fuel to any one of cylinders #1 to #4, while increasing an amount of fuel supplied to remaining cylinders. When a temperature of a three-way catalyst becomes equal to or higher than a first temperature, the CPU increases an injection amount to lower a temperature of exhaust gas. When the temperature of the three-way catalyst becomes equal to or higher than the first temperature during the execution of the regeneration process, the CPU does not increase the injection amount.

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 and an outlet end with an axial length L; a first catalytic region comprising a first platinum group metal (PGM) component and a first oxygen storage capacity (OSC) material, wherein the first OSC material has a fresh specific surface area (SSA) of at least 10 m.sup.2/g; and wherein the first OSC material has an SSA difference of no more than 30 m.sup.2/g between the fresh first OSC material and the aged first OSC material.

Provided is, for example, an exhaust gas-purifying three-way catalyst which is suppressed in particle growth due to sintering of a catalytically active component on a carrier in exposure to a high temperature and thus is enhanced in purification performance, and a method for producing the same, as well as an integral structure type exhaust gas-purifying catalyst using the same. The exhaust gas-purifying three-way catalyst of the present invention includes a composite particle which contains a base material particle having a pore size of 100 to 650 nm as measured by a mercury intrusion method and a catalytically active particle of a platinum group element supported on the base material particle, in which a content proportion of the catalytically active particle is 0.001 to 30% by mass in total in terms of metal of the platinum group element, based on a total amount of the composite particle.

The disclosure relates to an exhaust gas aftertreatment system with a turbine arranged in the exhaust gas line and with a main catalytic converter arranged downstream from the turbine, wherein the exhaust gas line has a bypass line and a bypass connector, wherein the bypass line opens downstream from the turbine, wherein a main particle filter and, in the bypass line, a catalytic converter are provided, wherein the bypass valve a1) is formed as a three-way valve is and forms the bypass connector a2) the bypass valve is formed as a three-way valve and is provided at the opening b1) is positioned in the bypass line, wherein an exhaust gas flap is provided upstream from the opening in the exhaust gas line b2) the exhaust gas line is formed without exhaust gas flaps downstream from the bypass connector and upstream from the opening, and the catalytic converter has a three-way coating or the respective main catalytic converter has a DOC coating.

An exhaust-gas purification system of an internal combustion engine includes an electrically heated catalytic device and a three-way catalytic device. The electrically heated catalytic device includes a first honeycomb base having a large number of honeycomb passages and a first catalyst component that is supported on, by a predetermined thin-film treatment, surfaces that define the honeycomb passages and that contains one or more types of noble metals. The three-way catalytic device includes a second honeycomb base having a large number of honeycomb passages and a second catalyst component that is supported on surfaces defining the honeycomb passages and that contains one or more types of noble metals. The total noble metal content per unit volume of the second honeycomb base is higher than the total noble metal content per unit volume of the first honeycomb base.

The exhaust purification device of an internal combustion engine comprises a catalyst 20 arranged in an exhaust passage and able to store oxygen; and an air-fuel ratio control device configured to control an air-fuel ratio of inflowing exhaust gas flowing into the catalyst. The air-fuel ratio control device is configured to perform a distribution forming control controlling the air-fuel ratio of the inflowing exhaust gas so that in the catalyst, a first region with an oxygen storage amount of equal to or greater than a predetermined value and a second region with an oxygen storage amount of less than the predetermined value are alternately formed along an axial direction of the catalyst. The total number of the first region and the second region formed by the distribution forming control is equal to or greater than three.

Disclosed is a catalyst for removing saturated hydrocarbon including an acidic support including porous alumina (Al.sub.2O.sub.3) and having higher acidity than alumina, and an active metal including platinum (Pt) and supported on the acidic support.