Abstract: A catalytic converter includes a substrate (1) and a catalyst layer (3). The catalyst layer includes a bottom catalyst layer (4), a first top catalyst layer (6) and a second top catalyst layer (7). The second top catalyst layer is provided on a downstream side relative to the first top catalyst layer. The first top catalyst layer is made of a ceria-free zirconia composite oxide support and rhodium. The second top catalyst layer is made of a ceria-containing zirconia composite oxide support and rhodium. The first top catalyst layer has a length that is X % of the entire length of the substrate. The second top catalyst layer has a length that is 100?X % of the entire length of the substrate. A ratio of a density of rhodium in the first top catalyst layer to a density of rhodium in the second top catalyst layer is at least 1 and at most 3.

Abstract: A catalytic converter (10) includes a base material and a catalyst layer (3). The catalyst layer has a lower catalyst layer (4) and an upper catalyst layer (5). The upper catalyst layer is constituted by a first upper catalyst layer (6) and a second upper catalyst layer (7). The first upper catalyst layer is formed of a first carrier, which is formed of a ceria-containing oxide, and rhodium supported on the first carrier. The second upper catalyst layer is formed of a second carrier and rhodium supported on the second carrier. The second carrier does not contain ceria and is formed of one oxide selected from among zirconia and alumina. A length of the first upper catalyst layer is X % (30 to 70%) of an overall length of the base material. A length of the second upper catalyst layer is 100?X % of the overall length of the base 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: A catalytic converter including: a cell structured first substrate; and a cell structured second substrate provided at a downstream side of the first substrate. The first substrate has a uniform cell density. The second substrate includes a center area with a first cell density and a surrounding area with a second cell density that is lower than the first cell density. The first substrate and the second substrate are mounted in tandem.

Abstract: A catalytic converter (10) includes i) an outer tube (1) that includes a cylindrical portion (1a), an upstream-side cone portion (1b), and a downstream-side cone portion (1c), and ii) a substrate (2) having a cell structure that is arranged in the cylindrical portion (1a) of the outer tube (1). The substrate (2) has a center region (2a) where a cell density is relatively high and a peripheral region (2b) where the cell density is relatively low, in a cross-section that is orthogonal to a length direction of the substrate (2). A projection portion when a connecting portion (5) of the exhaust duct (4) and the downstream-side cone portion (1c) is projected onto the substrate (2) is within the center region (2a).

Abstract: A catalyst converter includes: a substrate (1) having a cell structure formed of a center area (1A) having the highest cell density, a peripheral area (1C) having the lowest cell density, and an intermediate area (1B) having the cell density between that of the center area and that of the peripheral area; a first catalyst layer formed in the center area (1A); a second catalyst layer formed in the intermediate area (1B); and a third catalyst layer formed in the peripheral area (1C). A length in a longitudinal direction of the second catalyst layer is longer than that of the first catalyst layer. A length in the longitudinal direction of the third catalyst layer is longer than that of the second catalyst layer. A ratio of the length in the longitudinal direction of the first catalyst layer to the length of the substrate is 65% or more.

Abstract: An exhaust gas purification catalyst includes a composite oxide support, and a precious metal catalyst supported on the composite oxide support. The composite oxide support includes alumina, zirconia, ceria, a first additive element oxide and a second additive element oxide. The first additive element oxide contains an additive element selected from the group consisting of rare earth elements excluding cerium and alkali earth elements. The second additive element oxide contains an additive element selected from the group consisting of rare earth elements excluding cerium and alkali earth elements. In the composite oxide support, alumina is contained in a range of 30 to 40% by mass and zirconia is contained in a range of 36 to 46% by mass.

Abstract: Provide is a catalytic converter including a substrate which includes regions having different cell densities, in which exhaust gas purification performance is superior in all the regions of the substrate. A catalytic converter 10 includes catalyst layers in which a noble metal catalyst is supported on a support in surfaces of cell walls 2 of a substrate 1 having a cell structure in a longitudinal direction of the substrate 1 in which gas flows, in which the substrate 1 has a first region 1A having a relatively high cell density and a second region 1B having a relatively low cell density, and a ratio of a thickness of a catalyst layer 3A in the second region 1B to a thickness of a catalyst layer 3 in the first region 1A is in a range of more than 0.95 times and 1.2 times or less.

Abstract: Provided is a a catalytic converter capable of obtaining superior NOx purification performance while reducing the amount of a noble metal catalyst. A catalytic converter 10 includes: a substrate 1 having a cell structure in which exhaust gas flows; and catalyst layers 3 that are formed on cell wall surfaces 2 of the substrate 1. The catalyst layers 3 include a first catalyst layer 4 disposed on an upstream side of the substrate 1 in an exhaust gas flow direction and a second catalyst layer 5 disposed on a downstream side of the substrate in the exhaust gas flow direction. The first catalyst layer 4 is formed of a support and rhodium which is a noble metal catalyst supported on the support. The second catalyst layer 5 is formed of a support and palladium or platinum which is a noble metal catalyst supported on the support.

Abstract: Provided is a catalytic converter in which the entire catalyst constituting the catalytic converter can be efficiently utilized to purify exhaust gas, and the emission of hydrogen sulfide can be suppressed. A catalytic converter 10 includes catalyst layers 2A, 2B formed of a noble metal catalyst that are formed on cell wall surfaces of a substrate 1 having a cell structure in a longitudinal direction of the substrate 1 in which gas flows, in which the substrate 1 has a center region 1A having a relatively high cell density and a peripheral region 1B having a relatively low cell density, and lengths of the catalyst layers 2A, 2B of the center region 1A and the peripheral region 1B in the longitudinal direction are the same as each other, or the length of the catalyst layer 2B in the longitudinal direction is shorter than that of the catalyst layer 2A.

Abstract: There is provided a catalytic converter that offers high exhaust gas cleaning performance by effectively utilizing a whole catalyst that constitutes the catalytic converter. In a catalytic converter (10), catalytic layers (2A, 2B) made of a noble metal catalyst are formed on cell wall surfaces of a substrate (1) having a cell structure, and the catalytic layers (2A, 2B) extend in a longitudinal direction of the substrate (1) along which gas flows. The substrate (1) has a central region (1A) having a relatively high cell density and a peripheral region (1B) having a relatively low cell density. The length of each of the catalytic layers (2B) in the longitudinal direction in the peripheral region (1B) is longer than the length of each of the catalytic layers (2A) in the longitudinal direction in the central region (1A).

Abstract: An objective of the present invention is to provide a method for producing a catalyst for exhaust gas removal having excellent heat tolerance and purification performance within a wide range of atmospheres and a catalyst obtained by the production method. The present invention relates to a method for supporting catalyst metal particles, comprising: (a) adding an iridium precursor and a palladium precursor to a solvent containing at least one member selected from the group consisting of polyvinylpyrrolidone, N-methylpyrrolidone, N-vinyl-2-pyrrolidone, and ethylene glycol; (b) adding a reducing agent to the obtained catalyst metal colloid; (c) obtaining a concentrated solution containing catalyst metal particles by subjecting the obtained solution to heat reflux; and (d) supporting the catalyst metal particles on a carrier, wherein the iridium content of the catalyst metal particles accounts for 3% to 10% by mass of the total mass of iridium and palladium.

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: An object of the present invention is to provide an exhaust gas catalyst that can achieve high purification performance.

Abstract: A catalytic converter including: a cell structured first substrate; and a cell structured second substrate provided at a downstream side of the first substrate. The first substrate has a uniform cell density. The second substrate includes a center area with a first cell density and a surrounding area with a second cell density that is lower than the first cell density. The first substrate and the second substrate are mounted in tandem.

Abstract: The herein disclosed exhaust gas purification catalyst is an exhaust gas purification catalyst that is provided with a porous carrier 40 and palladium 50 supported on this porous carrier 40. The porous carrier 40 is provided with an alumina carrier 42 formed of alumina and with a CZ carrier 44 formed of a ceria-zirconia complex oxide. Barium is added to both the alumina carrier 42 and the CZ carrier 44. Here, an amount of barium added to the alumina carrier 42 is an amount that corresponds to 10 mass % to 15 mass % relative to a total mass of the alumina carrier 42 excluding the barium, and an amount of barium added to the CZ carrier 44 is an amount that corresponds to 5 mass % to 10 mass % relative to a total mass of the CZ carrier 44 excluding the barium.

Abstract: An exhaust gas purification catalyst includes a composite oxide support, and a precious metal catalyst supported on the composite oxide support. The composite oxide support includes alumina, zirconia, ceria, a first additive element oxide and a second additive element oxide. The first additive element oxide contains an additive element selected from the group consisting of rare earth elements excluding cerium and alkali earth elements. The second additive element oxide contains an additive element selected from the group consisting of rare earth elements excluding cerium and alkali earth elements. In the composite oxide support, alumina is contained in a range of 30 to 40% by mass and zirconia is contained in a range of 36 to 46% by mass.

Abstract: An exhaust gas purification catalyst is provided with a substrate and a catalyst coating layer formed on the surface of the substrate. The catalyst coating layer is formed into a layered structure having upper and lower layers, with a lower layer being closer to the surface of the substrate and an upper layer being relatively farther therefrom. The catalyst coating layer is provided with Rh and Pd as precious metal catalysts and is provided with an OSC material having an oxygen storage capacity as a support. The Rh is disposed in the upper layer of the catalyst coating layer, and the Pd is disposed in both the upper layer and the lower layer of the catalyst coating layer. At least a portion of the Pd in the upper layer and in the lower layer is supported on the OSC material. The mass ratio of the Pd disposed in the upper layer to the Pd disposed in the lower layer is not more than 0.4.

Abstract: An exhaust gas purification catalyst has a substrate, a lower catalyst layer that is formed on the substrate and contains at least one of Pd and Pt, and an upper catalyst layer that is formed on the lower catalyst layer and contains Rh. A region that does not contain the upper catalyst layer is disposed on the exhaust gas upstream side of this exhaust gas purification catalyst. The lower catalyst layer includes a front-stage lower catalyst layer on the exhaust gas upstream side and a rear-stage lower catalyst layer on the exhaust gas downstream side. The front-stage lower catalyst layer contains an oxygen storage material.

Abstract: The herein disclosed exhaust gas purification catalyst is an exhaust gas purification catalyst that is provided with a porous carrier 40 and palladium 50 supported on this porous carrier 40. The porous carrier 40 is provided with an alumina carrier 42 formed of alumina and with a CZ carrier 44 formed of a ceria-zirconia complex oxide. Barium is added to both the alumina carrier 42 and the CZ carrier 44. Here, an amount of barium added to the alumina carrier 42 is an amount that corresponds to 10 mass % to 15 mass % relative to a total mass of the alumina carrier 42 excluding the barium, and an amount of barium added to the CZ carrier 44 is an amount that corresponds to 5 mass % to 10 mass % relative to a total mass of the CZ carrier 44 excluding the barium.