An engine exhaust aftertreatment device, comprising a first exhaust treatment unit and/or a second exhaust treatment unit; the first exhaust treatment unit comprises a first bypass pipeline (1) and a first connection pipe (4) provided between a DPF (2) and an SCR (3), one end of the first bypass pipeline (1) being in communication with a turbine front exhaust pipe (9), and the other end of the first bypass pipeline being in communication with the first connection pipe (4); the second exhaust treatment unit comprises a second bypass pipeline (19) and a second connection pipeline (20) provided between a DOC (13) and the DPF (2), one end of the second bypass pipeline (19) being in communication with the turbine front exhaust pipe (9), and the other end of the second bypass pipeline being in communication with the second connection pipeline (20); when it is detected that an engine (11) satisfies a starting condition of the first exhaust treatment unit, the first exhaust treatment unit starts; and when it is detected that the engine (11) satisfies a starting condition of the second exhaust treatment unit, the second exhaust treatment unit starts. Said device and method greatly improve the exhaust treatment efficiency and reduce the risk of exhaust excessive emission.

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.

This disclosure is directed to catalyst compositions, catalytic articles for purifying exhaust gas emissions and methods of making and using the same. In particular, the disclosure relates to a catalytic article including a catalytic material on a substrate, wherein the catalytic material has a first layer and a second layer. The first layer provides effective lean NO.sub.x trap functionality and the second layer provides effective three-way conversion of carbon monoxide, hydrocarbons, and nitrogen oxides (NO.sub.x).

Provided are a novel synthesis technique for producing pure phase aluminosilicate zeolite and a catalyst comprising the phase pure zeolite in combination with a metal, and methods of using the same.

An exhaust gas purification device includes a first catalyst, a bypass pipe, a second catalyst, and a switching controller. The first catalyst is provided in an exhaust pipe. The bypass pipe branches from a first portion of the exhaust pipe. The first portion is located upstream of the first catalyst. The bypass pipe is recoupled to a second portion of the exhaust pipe. The second portion is located upstream of the first catalyst. The second catalyst is provided in the bypass pipe. The switching controller is configured to switch a flow path of an exhaust gas to the bypass pipe based on a deterioration degree of the first catalyst.

An exhaust passage includes a main passage and bypass passage, a catalyst, an exhaust control valve, and an HC adsorbent in the bypass passage. The exhaust control valve is controlled so that, when a temperature of the catalyst is higher than a predetermined sintering occurrence temperature, the quality of HC desorbed from the HC adsorbent is greater when the air-fuel ratio of the exhaust gas flowing through the upstream exhaust passage portion is a lean air-fuel ratio compared to when it is a stoichiometric air-fuel ratio or rich air-fuel ratio, or the quality of HC desorbed from the HC adsorbent is greater when the air-fuel ratio of the exhaust gas flowing through the upstream exhaust passage portion is a larger lean air-fuel ratio compared to when it is a smaller lean air-fuel ratio.

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; an inlet catalyst layer beginning at the inlet end and extending for less than the axial length L, wherein the inlet catalyst layer comprises an inlet palladium component; an outlet catalyst layer beginning at the outlet end and extending for less than the axial length L, wherein the outlet catalyst layer comprises an outlet rhodium component; and wherein the outlet catalyst layer overlaps with the inlet catalyst layer.

The present invention relates to a catalyst comprising a carrier substrate of the length L extending between substrate ends a and b and two washcoat zones A and B, wherein washcoat zone A comprises a zeolite having a smallest lower channel width of at least 0.4 nm and extends starting from substrate end a over a part of the length L, and washcoat zone B comprises the same components as washcoat A and palladium and extends from substrate end b over a part of the length L, wherein L=L.sub.A+L.sub.B, wherein L.sub.A is the length of washcoat zone A and L.sub.B is the length of substrate length B.

An internal combustion engine includes an engine body, an HC adsorption and removal catalyst in an exhaust, including an HC adsorption layer and a catalyst layer, and having a desorption temperature of the HC from the HC adsorption layer lower than an HC removal temperature of a temperature where a rate of removal of HC at the catalyst layer is a predetermined rate or more when an air-fuel ratio of the exhaust is near the stoichiometric air-fuel ratio, and an air feed device for feeding air to the HC adsorption and removal catalyst. A control device for an internal combustion engine includes an air feed control for controlling feed air to the HC adsorption and removal catalyst when a condition stands. The condition includes the temperature of the HC adsorption and removal catalyst being the desorption temperature or more and less than the HC removal temperature.

A method of manufacturing a catalyst article, the method comprising: providing a complex of a polyphenol and a PGM, the PGM comprising rhodium and/or platinum, the polyphenol comprising an ester functional group; 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.