Abstract: Provided is an exhaust gas purification catalyst improved in warm-up performance while suppressing HC poisoning of a noble metal in an atmosphere in which an air-fuel ratio (A/F) is rich and the HC poisoning easily occurs. The present disclosure relates to an exhaust gas purification catalyst that includes a substrate and a catalyst coating layer coated on the substrate. The catalyst coating layer includes a lower coating layer coated on the substrate and an upper coating layer coated on the lower coating layer. The lower coating layer contains a noble metal. The upper coating layer contains Pd and/or Pt. The Pd and/or Pt contained in the upper coating layer is supported on A12O3 by a certain amount or more. A thickness of the upper coating layer is adjusted.

Abstract: A catalyst for purification of exhaust gas including a substrate, and a catalyst coat layer which is formed on a surface of the substrate and contains catalyst particles, wherein the catalyst coat layer has an average thickness ranging 25 to 150 ?m, a void fraction, as determined by scanning electron microscope observation of a cross-section of the catalyst coat layer, ranging 1.5 to 8.0% by volume, 60 to 90% by volume of all voids in the catalyst coat layer are high-aspect ratio pores which have equivalent circle diameters ranging 2 to 50 ?m in a cross-sectional image of a cross-section of the catalyst coat layer perpendicular to a flow direction of exhaust gas in the substrate, and which ratios of 5 or higher, the high-aspect ratio pores have an average aspect ratio ranging 10 to 50, and a noble metal is supported on the entire catalyst coat layer.

Abstract: An exhaust gas purification device includes a substrate including an upstream end and a downstream end, the substrate having a length Ls between the upstream end and the downstream end; a first catalyst layer containing first catalyst particles, extending across a first region, and being in contact with the substrate, the first region extending between the upstream end and a first position, the first position being at a first distance La from the upstream end toward the downstream end; and a second catalyst layer containing second catalyst particles, extending across a second region, and being in contact with the substrate, the second region extending between the downstream end and a second position, the second position being at a second distance Lb from the downstream end toward the upstream end. The first catalyst layer has an inner surface defining macropores.

Abstract: An overall exhaust gas purification function based on an NOx reduction function and an HC oxidation function in an NSR catalyst arranged in an exhaust passage of an internal combustion engine is improved. In the NSR catalyst, a portion of an NOx storage catalyst layer supported by a carrier, which extends from its upstream end to an X % (0<X?75) of an overall length thereof along the flow of exhaust gas, forms an upstream side catalyst layer, and a portion of the NOx storage catalyst layer at the downward side of the upstream side catalyst layer along the flow of exhaust gas forms a downstream side catalyst layer. The upstream side catalyst layer does not contain potassium (K) as an NOx storage material, but the downstream side catalyst layer contains potassium (K) as an NOx storage material.

Abstract: An exhaust purification apparatus for an internal combustion engine is provided with an NOx storage and reduction type catalyst in an exhaust passage. The NOx storage and reduction type catalyst comprises a base member, an upstream side coat layer arranged on the base member, and a downstream side coat layer arranged at a downstream side in the direction of exhaust flow from the upstream side coat layer. The upstream side coat layer does not include a Ce-containing oxide but includes a precious metal catalyst. The downstream side coat layer contains a Ce-containing oxide and precious metal catalyst. A length of the upstream side coat layer is a length of 5 to 62.5% of the total length of the upstream side coat layer and the downstream side coat layer, while the remaining part of the coat layer aside from the upstream side coat layer is the downstream side coat layer.

Abstract: An exhaust gas control apparatus includes a NOx storage-reduction catalyst, and an injector capable of supplying a reducing agent containing hydrocarbon and carbon monoxide to the NOx storage-reduction catalyst and adjusting a CO ratio that is a ratio of carbon monoxide to hydrocarbon supplied to the NOx storage-reduction catalyst. The exhaust gas control apparatus controls the injector such that the CO ratio becomes lower when the NOx removal treatment is started than when the NOx removal treatment is ended.

Abstract: An exhaust purification apparatus for an internal combustion engine is provided with an NOx storage and reduction type catalyst in an exhaust passage. The NOx storage and reduction type catalyst comprises a base member, an upstream side coat layer arranged on the base member, and a downstream side coat layer arranged at a downstream side in the direction of exhaust flow from the upstream side coat layer. The upstream side coat layer does not include a Ce-containing oxide but includes a precious metal catalyst. The downstream side coat layer contains a Ce-containing oxide and precious metal catalyst. A length of the upstream side coat layer is a length of 5 to 62.5% of the total length of the upstream side coat layer and the downstream side coat layer, while the remaining part of the coat layer aside from the upstream side coat layer is the downstream side coat layer.

Abstract: An overall exhaust gas purification function based on an NOx reduction function and an HC oxidation function in an NSR catalyst arranged in an exhaust passage of an internal combustion engine is improved. In the NSR catalyst, a portion of an NOx storage catalyst layer supported by a carrier, which extends from its upstream end to an X % (0<X?75) of an overall length thereof along the flow of exhaust gas, forms an upstream side catalyst layer, and a portion of the NOx storage catalyst layer at the downward side of the upstream side catalyst layer along the flow of exhaust gas forms a downstream side catalyst layer. The upstream side catalyst layer does not contain potassium (K) as an NOx storage material, but the downstream side catalyst layer contains potassium (K) as an NOx storage material.

Abstract: The exhaust gas purification apparatus 100 according to the present invention is provided with an exhaust gas purification catalyst 40, an upstream O2 sensor 14, a downstream O2 sensor 15, and a control section 30 that executes main F/B control and sub-F/B control. This exhaust gas purification apparatus 100 contains, on a support in a prescribed region 45 from a catalyst-outlet-side end 43a at the downstream side of an exhaust gas purification catalyst 40, an OSC material having a pyrochlore structure and an OSC material having an oxygen storage rate that is faster than that of the OSC material having a pyrochlore structure.

Abstract: The exhaust gas purification apparatus 100 according to the present invention is provided with an exhaust gas purification catalyst 40, an upstream O2 sensor 14, a downstream O2 sensor 15, and a control section 30 that executes main F/B control and sub-F/B control. This exhaust gas purification apparatus 100 contains, on a support in a prescribed region 45 from a catalyst-outlet-side end 43a at the downstream side of an exhaust gas purification catalyst 40, an OSC material having a pyrochlore structure and an OSC material having an oxygen storage rate that is faster than that of the OSC material having a pyrochlore structure.

Abstract: Disclosed is an exhaust gas purifying catalyst in which grain growth of a noble metal particle supported on a support is suppressed. Also disclosed is a production process for producing an exhaust gas purifying catalyst. The exhaust gas purifying catalyst comprises a crystalline metal oxide support and a noble metal particle supported on the support, wherein the noble metal particle is epitaxially grown on the support, and wherein the noble metal particle is dispersed and supported on the outer and inner surfaces of the support. The process for producing an exhaust gas purifying catalyst comprises masking, in a solution, at least a part of the surface of a crystalline metal oxide support by a masking agent, introducing the support into a noble metal-containing solution containing a noble metal, and drying and firing the support and the noble metal-containing solution to support the noble metal on the support.

Abstract: Disclosed is an exhaust gas purifying catalyst in which grain growth of a noble metal particle supported on a support is suppressed. Also, disclosed is a production process of an exhaust gas purifying catalyst, by which the above exhaust gas purifying catalyst can be produced. The exhaust gas purifying catalyst comprises a crystalline metal oxide support and a noble metal particle supported on the support, wherein the noble metal particle is epitaxially grown on the support, and wherein the noble metal particle is dispersed and supported on the outer and inner surfaces of the support. The process for producing an exhaust gas purifying catalyst comprises masking, in a solution, at least a part of the surface of a crystalline metal oxide support by a masking agent, introducing the support into a noble metal-containing solution containing a noble metal, and drying and firing the support and the noble metal-containing solution to support the noble metal on the support.

Abstract: Disclosed is an exhaust gas purifying catalyst in which grain growth of a noble metal particle supported on a support is suppressed. Also disclosed is a production process for producing an exhaust gas purifying catalyst. The exhaust gas purifying catalyst comprises a crystalline metal oxide support and a noble metal particle supported on the support, wherein the noble metal particle is epitaxially grown on the support, and wherein the noble metal particle is dispersed and supported on the outer and inner surfaces of the support. The process for producing an exhaust gas purifying catalyst comprises masking, in a solution, at least a part of the surface of a crystalline metal oxide support by a masking agent, introducing the support into a noble metal-containing solution containing a noble metal, and drying and firing the support and the noble metal-containing solution to support the noble metal on the support.

Abstract: Disclosed is an exhaust gas purifying catalyst in which grain growth of a noble metal particle supported on a support is suppressed. Also, disclosed is a production process of an exhaust gas purifying catalyst, by which the above exhaust gas purifying catalyst can be produced. The exhaust gas purifying catalyst comprises a crystalline metal oxide support and a noble metal particle supported on the support, wherein the noble metal particle is epitaxially grown on the support, and wherein the noble metal particle is dispersed and supported on the outer and inner surfaces of the support. The process for producing an exhaust gas purifying catalyst comprises masking, in a solution, at least a part of the surface of a crystalline metal oxide support by a masking agent, introducing the support into a noble metal-containing solution containing a noble metal, and drying and firing the support and the noble metal-containing solution to support the noble metal on the support.