A NO.sub.x absorber catalyst for treating an exhaust gas from a diesel engine. The NO.sub.x absorber catalyst comprises a first NO.sub.x absorber material comprising a molecular sieve catalyst, wherein the molecular sieve catalyst comprises a noble metal and a molecular sieve, and wherein the molecular sieve contains the noble metal; a second NO.sub.x absorber material comprising palladium (Pd) supported on an oxide of cerium; and a substrate having an inlet end and an outlet end.

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.

An object of the present invention is to provide an exhaust gas purification system which exhibits high exhaust gas purification performance. The present invention provides an exhaust gas purification system including: a carrier containing aluminum oxide; an exhaust gas purification device including a catalyst provided on the carrier and containing gallium, and connected to an internal combustion engine; and a system connected to the exhaust gas purification device for increasing an oxygen concentration. The system for increasing an oxygen concentration provides an oxygen concentration higher than that of a post combusted gas of the internal combustion engine.

An arrangement structure of an exhaust gas sensor includes an exhaust pipe that extends from an engine for a vehicle to form a part of an exhaust flow path, a catalytic device that purifies exhaust gas flowing through the exhaust flow path, and a first exhaust gas sensor that detects a predetermined component in the exhaust gas. The exhaust pipe is led out from a front side of the engine to one side in a left-right direction of the engine, and extends rearward so as to be routed on a lateral side of the engine. The catalytic device is arranged in the middle of the exhaust pipe on the lateral side of the engine. The first exhaust gas sensor is arranged on the lateral side of the engine and on an upstream side or a downstream side of the catalytic device in the exhaust pipe.

A method and a control device for regulating a modeled fill level of an exhaust gas component reservoir of a catalytic converter of an internal combustion engine. Regulation of the modeled fill level is accomplished using a system model. An actual maximum storage capacity of the catalytic converter for the exhaust gas component is ascertained during operation of the internal combustion engine and is taken into consideration in regulating the modeled fill level.

An exhaust gas control apparatus includes: a honeycomb substrate including an inflow cell and an outflow cell adjacent to each other with a partition wall sandwiched between the inflow cell and the outflow cell; a first sealing part provided at an outflow side end of the inflow cell, and a second sealing part provided at an inflow side end of the outflow cell; and a catalyst layer provided on the partition wall, and at least one of the first sealing part and the second sealing part is an OSC material-containing sealing part containing an OSC material and a sealant, and a concentration of the OSC material in the OSC material-containing sealing part is uniform in an extending direction.

The present disclosure provides an exhaust gas purification catalyst having an improved Rh activation, which comprises a substrate and a catalyst coat layer formed on the substrate, the catalyst coat layer having a two-layer structure, wherein the catalyst coat layer includes an upstream portion on an upstream side and a downstream portion on a downstream side in an exhaust gas flow direction, and a part or all of the upstream portion is formed on a part of the downstream portion, wherein the upstream portion contains Rh fine particles and Pt, wherein the Rh fine particles have an average particle size measured by a transmission electron microscope observation of 1.0 nm or more to 2.0 nm or less, and a standard deviation of the particle size of 0.8 nm or less, and wherein the downstream portion contains Rh.

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.

A substrate (11) includes an inflow-side cell (21), an outflow-side cell (22), and a porous, gas-permeable partition wall (23) that separates the inflow-side cell (21) and the outflow-side cell (22) from each other, and also includes a first catalyst portion (14) that is provided on a side of the partition wall (23) that faces the inflow-side cell (21) at least at a portion in upstream side in an exhaust gas flow direction, and a second catalyst portion (15) that is provided on a side of the partition wall that faces the outflow-side cell at least at a portion in downstream side. With respect to a pore volume of pores with a pore size of 10 to 18 m, when a measured value of the pore volume in the first catalyst portion (14) and the partition wall (23) within a region where the first catalyst portion (14) is provided is defined as a first pore volume, and a measured value of the pore volume in the second catalyst portion (15) and the partition wall (23) within a region where the second catalyst portion (15) is provided is defined as a second pore volume, the first pore volume is greater than the second pore volume. A catalytically active component contained in the first catalyst portion (14) and a catalytically active component contained in the second catalyst portion (15) are of different types.

A method and a control device for regulating a modeled fill level of an exhaust gas component reservoir of a catalytic converter of an internal combustion engine. Regulation of the modeled fill level is accomplished using a system model. An actual maximum storage capacity of the catalytic converter for the exhaust gas component is ascertained during operation of the internal combustion engine and is taken into consideration in regulating the modeled fill level.