Abstract: Provided are an oxidation catalyst for exhaust gas purification that removes toxic materials from exhaust gas emitted from a diesel engine, a catalyst structure for exhaust gas purification that contains the catalyst, and a method for purifying exhaust gas that uses the catalyst structure and can efficiently remove toxic materials from exhaust gas at low temperatures. The oxidation catalyst for exhaust gas purification contains either or both of titania (A) and a zeolite component (B) as a carrier; and a noble metal component (C) supported on the carrier. The zeolite component (B) contains a H-Beta type zeolite in a quantity of not less than 90% by weight relative to the total quantity of the zeolite component (B). The content of each component in the whole catalyst is 55 to 75% by weight for the titania (A), 15 to 25% by weight for the zeolite component (B), and 0.05 to 4% by weight for the noble metal component (C).

Abstract: An apparatus for purifying exhaust gas exhausted from an internal combustion engine, using two or more honeycomb structure-type catalysts (X) and (Y). The catalyst (X) contains the support material of the zirconium oxide as a main component which loads a Rh component on the support material of zirconium oxide and substantially does not contain a cerium component, and a cerium-containing oxide which substantially does not load the Rh component, and the catalyst (X) does not substantially contain Pt component and Pd component. The catalyst (Y) contains the support material of the cerium-zirconium composite oxide as a main component which loads a Rh component on the support material of cerium-zirconium composite oxide and which contains cerium of 1 to 20% by weight, in an oxide equivalent, and zirconium of 99 to 80% by weight, in an oxide equivalent, and the catalyst (Y) does not substantially contain Pt component and Pd component.

Abstract: An exhaust gas purification catalyst, which is suitable as a three way catalyst for efficiently purifying carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx) in exhaust gas discharged from a gasoline automobile and exhaust gas purification apparatus using the same and an exhaust gas purification method. <The upper layer> A catalyst composition having an activated metal (A), a heat resistant inorganic oxide (B) and a cerium-zirconium-type composite oxide (C) containing a pyrochlore phase in a crystal structure, wherein the activated metal (A) is rhodium. <The lower layer> A catalyst composition having an activated metal (A), a heat resistant inorganic oxide (B) and a cerium-containing oxide (C?) having a cubic crystal and/or tetragonal crystal structure as a major crystal structure, wherein the activated metal (A) is palladium, or palladium and platinum.

Abstract: A catalyst system to be used in an automobile exhaust gas purification apparatus which exerts excellent purification capability to a nitrogen oxide, even when hydrocarbon concentration varies, by subjecting exhaust gas discharged from an automotive internal engine to contacting with a catalyst, an exhaust gas purification apparatus using the same, and an exhaust gas purification method. A catalyst system etc.

Abstract: The present invention provides a catalyst system for vehicle exhaust gas purification devices which exhibit excellent capacity of removing nitrogen oxide emissions from internal combustion engine exhaust gases when they are brought into contact with the catalyst even when hydrocarbon concentration in exhaust gases varies, exhaust gas purification device using the same and method for purification of exhaust gases.

Abstract: An exhaust gas purification catalyst, which is suitable as a Three Way Catalyst for efficiently purifying carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx) in exhaust gas discharged from a gasoline automobile, an exhaust gas purification apparatus using the same and an exhaust gas purification method. It is provided by an exhaust gas purification catalyst, wherein catalyst components for purifying hydrocarbons (HC), carbon monoxide (CO) and nitrogen oxides (NOx) contained in exhaust gas are coated onto a honeycomb type structure as a catalyst composition layer, characterized in that the catalyst components comprise an activated metal (A), a heat resistant inorganic oxide (B) and a cerium-zirconium composite oxide (c) containing a pyrochlore phase in a crystal structure, in the same catalyst composition layer, and the activated metal (A) is a palladium and a rhodium and does not contain a platinum.

Abstract: An exhaust gas purification catalyst, which is suitable as a Three way catalyst for efficiently purifying carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx) in exhaust gas discharged from a gasoline automobile, an exhaust gas purification apparatus using the same and an exhaust gas purification method. <The Upper Layer> A catalyst composition having an activated metal (A), a heat resistant inorganic oxide (B) and a cerium-zirconium-type composite oxide (C) containing a pyrochlore phase in a crystal structure, wherein the activated metal (A) is rhodium. <The Lower Layer> A catalyst composition having an activated metal (A), a heat resistant inorganic oxide (B) and a cerium-containing oxide (C?) having a cubic crystal and/or a tetragonal crystal as a major crystal structure, wherein the activated metal (A) is palladium, or palladium and platinum.

Abstract: An apparatus of a catalyst for purifying exhaust gas suitable as a three-way catalyst (TWC) apparatus to be used for purifying carbon monoxide (CO), a hydrocarbon (HC) and a nitrogen oxide (NOx) in exhaust gas exhausted from a gasoline automobile, as well as a method for purifying exhaust gas.

Abstract: A catalyst system to be used in an automobile exhaust gas purification apparatus which exerts excellent purification capability to a nitrogen oxide, even when hydrocarbon concentration varies, by subjecting exhaust gas discharged from an automotive internal engine to contacting with a catalyst, an exhaust gas purification apparatus using the same, and an exhaust gas purification method. A catalyst system etc.

Abstract: The present invention provides a catalyst system for vehicle exhaust gas purification devices which exhibit excellent capacity of removing nitrogen oxide emissions from internal combustion engine exhaust gases when they are brought into contact with the catalyst even when hydrocarbon concentration in exhaust gases varies, exhaust gas purification device using the same and method for purification of exhaust gases.