Abstract: Provided is a methanation catalyst processing method capable of suppressing degradation of a catalyst performance. A methanation catalyst processing method of the present disclosure includes oxidizing nickel through a heat treatment of a methanation catalyst by supplying an oxygen gas containing oxygen to a reactor, the reactor housing the methanation catalyst containing the nickel as a catalyst component. In the oxidizing, the oxygen gas is supplied to the reactor such that the oxygen is supplied to 1 g of the methanation catalyst at a supply rate in a range of from 0.0213 mmol-O2/sec·g-cat. to 0.0638 mmol-O2/sec·g-cat., and a time period of the heat treatment of the methanation catalyst by supplying the oxygen gas to the reactor is set to 30 minutes or more.

Abstract: Provided is a methanation catalyst processing method capable of suppressing degradation of a catalyst performance. A methanation catalyst processing method of the present disclosure includes oxidizing nickel through a heat treatment of a methanation catalyst by supplying an oxygen gas containing oxygen to a reactor, the reactor housing the methanation catalyst containing the nickel as a catalyst component. In the oxidizing, the oxygen gas is supplied to the reactor such that the oxygen is supplied to 1 g of the methanation catalyst at a supply rate in a range of from 0.0213 mmol-O2/sec·g-cat. to 0.0638 mmol-O2/sec·g-cat., and a time period of the heat treatment of the methanation catalyst by supplying the oxygen gas to the reactor is set to 30 minutes or more.

Abstract: An exhaust gas controlling catalyst includes zirconia particles; ceria particles which contact the zirconia particles, of which a mean particle size is smaller than a mean particle size of the zirconia particles; and an active metal that is supported on at least the ceria particles in a dispersed manner.

Abstract: An exhaust gas purification catalyst includes an alumina support, a silica layer, and active metal particles. The silica layer is formed on a surface of the alumina support. The active metal particles are formed of platinum and palladium, the platinum and the palladium being supported on the silica layer. A ratio of fine particles having a particle size of 2.0 nm or less to all the active metal particles is 50% or higher in terms of the number of particles, the fine particles being included in the active metal particles. A ratio of fine alloy particles having a palladium content ratio of 10 at % to 90 at % to all the fine particles is 50% or higher in terms of the number of particles, the fine alloy particles being included in the fine particles.

Abstract: An exhaust gas purification catalyst includes an alumina support, a silica layer, and active metal particles. The silica layer is formed on a surface of the alumina support. The active metal particles are formed of platinum and palladium, the platinum and the palladium being supported on the silica layer. A ratio of fine particles having a particle size of 2.0 nm or less to all the active metal particles is 50% or higher in terms of the number of particles, the fine particles being included in the active metal particles. A ratio of fine alloy particles having a palladium content ratio of 10 at % to 90 at % to all the fine particles is 50% or higher in terms of the number of particles, the fine alloy particles being included in the fine particles.

Abstract: An exhaust gas control apparatus for an internal combustion engine includes: a NOx purification catalyst arranged in an exhaust passage of the internal combustion engine; a degradation degree estimating unit estimating a degradation degree of the NOx purification catalyst; and an air-fuel ratio control unit adjusting an air-fuel ratio of exhaust gas flowing into the NOx purification catalyst, wherein, until the estimated degradation degree of the NOx purification catalyst reaches a predetermined degradation degree, the air-fuel ratio control unit adjusts the air-fuel ratio of the exhaust gas to a rich air-fuel ratio, and, when the estimated degradation degree of the NOx purification catalyst exceeds the predetermined degradation degree, the air-fuel ratio control unit changes the air-fuel ratio of the exhaust gas from the rich air-fuel ratio to a lean air-fuel ratio so that the NOx purification catalyst is regenerated.

Abstract: An exhaust gas control apparatus for an internal combustion engine includes: a NOx purification catalyst arranged in an exhaust passage of the internal combustion engine; a degradation degree estimating unit estimating a degradation degree of the NOx purification catalyst; and an air-fuel ratio control unit adjusting an air-fuel ratio of exhaust gas flowing into the NOx purification catalyst, wherein, until the estimated degradation degree of the NOx purification catalyst reaches a predetermined degradation degree, the air-fuel ratio control unit adjusts the air-fuel ratio of the exhaust gas to a rich air-fuel ratio, and, when the estimated degradation degree of the NOx purification catalyst exceeds the predetermined degradation degree, the air-fuel ratio control unit changes the air-fuel ratio of the exhaust gas from the rich air-fuel ratio to a lean air-fuel ratio so that the NOx purification catalyst is regenerated.

Abstract: An exhaust gas controlling catalyst includes zirconia particles; ceria particles which contact the zirconia particles, of which a mean particle size is smaller than a mean particle size of the zirconia particles; and an active metal that is supported on at least the ceria particles in a dispersed manner.

Abstract: A base metal exhaust gas control apparatus for an internal combustion engine includes a basic structure having a first-stage base metal catalyst that oxidizes HC and CO, and a second-stage base metal catalyst that reduces NOx. The first-stage base metal catalyst oxidizes HC more efficiently than it oxidizes CO.