Abstract: An exhaust gas purification system of the present disclosure includes a first exhaust gas purification device that purifies exhaust gas discharged from an internal combustion engine and a second exhaust gas purification device that additionally purifies the exhaust gas purified by the first exhaust gas purification device, wherein the exhaust gas is exhaust gas with a gaseous composition in which an amount of reducing agents is in excess compared to a stoichiometric gaseous composition and a gaseous composition in which an amount of oxidants is in excess compared to the stoichiometric gaseous composition are alternately switched between, the first exhaust gas purification device includes a three-way catalyst, and the second exhaust gas purification device includes an exhaust gas purification catalyst containing spinel-type MgAlxFe2.00?xO4.00 supporting particles on which Rh is supported, where 0.00<×?1.50.

Abstract: An exhaust gas purification system of the present disclosure includes a first exhaust gas purification device that purifies exhaust gas discharged from an internal combustion engine and a second exhaust gas purification device that additionally purifies the exhaust gas purified by the first exhaust gas purification device, wherein the exhaust gas is exhaust gas with a gaseous composition in which an amount of reducing agents is in excess compared to a stoichiometric gaseous composition and a gaseous composition in which an amount of oxidants is in excess compared to the stoichiometric gaseous composition are alternately switched between, the first exhaust gas purification device includes a three-way catalyst, and the second exhaust gas purification device includes an exhaust gas purification catalyst containing spinel-type MgAlxFe2.00?xO4.00 supporting particles on which Rh is supported, where 0.00<×?1.50.

Abstract: There is provided an exhaust gas purification system that allows efficient purification of NOx present in exhaust gas emitted from an internal combustion engine. The exhaust gas purification system of the disclosure comprises a first exhaust gas purification device that purifies exhaust gas emitted from an internal combustion engine, wherein the atmosphere alternately switches between a reducing agent-excess atmosphere and an oxidizing agent-excess atmosphere with respect to the stoichiometric atmosphere, and a second exhaust gas purification device that further purifies the exhaust gas that has been purified by the first exhaust gas purification device, wherein the first exhaust gas purification device has a three-way catalyst, and the second exhaust gas purification device has an exhaust gas purifying catalyst that comprises an AMn2O4 spinel-type oxide support (A=Mg, Zn or Li) on which a precious metal is supported.

Abstract: An object of the present disclosure is to provide an NOx storage material having sufficient NOx storage capacity even in a low temperature region and a production method thereof. An NOx storage material including a composite oxide of silver and gallium. The composite oxide of silver and gallium is preferably a delafossite-type composite oxide. The composite oxide is produced by dissolving a silver salt and a gallium salt in a solvent and baking the solution, wherein the molar ratio of silver:gallium is preferably from 2:8 to 7:3.

Abstract: NOx abatement compositions include cobalt oxide (Co3O4) doped with cerium, and have an overall formula Co3-xCe-O4, with cerium occupying tetrahedral and/or octahedral sites in the spinel structure. The NOx abatement compositions possess NOx storage and NOx direct decomposition activity. Dual stage NOx abatement devices include an upstream portion having the NOx abatement composition to adsorb and store NOx at low temperature, and then release the NOx at higher temperature to a downstream catalytic conversion portion.

Abstract: There is provided an exhaust gas purification system that allows efficient purification of NOx present in exhaust gas emitted from an internal combustion engine. The exhaust gas purification system of the disclosure comprises a first exhaust gas purification device that purifies exhaust gas emitted from an internal combustion engine, wherein the atmosphere alternately switches between a reducing agent-excess atmosphere and an oxidizing agent-excess atmosphere with respect to the stoichiometric atmosphere, and a second exhaust gas purification device that further purifies the exhaust gas that has been purified by the first exhaust gas purification device, wherein the first exhaust gas purification device has a three-way catalyst, and the second exhaust gas purification device has an exhaust gas purifying catalyst that comprises an AMn2O4 spinel-type oxide support (A=Mg, Zn or Li) on which a precious metal is supported.

Abstract: NOx abatement compositions include cobalt oxide (Co3O4) doped with cerium, and having an overall formula Co3-xCexO4, with cerium occupying tetrahedral and/or octahedral sites in the spinel structure. The NOx abatement compositions possess NOx storage and NOx direct decomposition activity. Dual stage NOx abatement devices include an upstream portion having the NOx abatement composition to adsorb and store NOx at low temperature, and then release the NOx at higher temperature to a downstream catalytic conversion portion.

Abstract: An object of the present disclosure is to provide an NOx storage material having sufficient NOx storage capacity even in a low temperature region and a production method thereof. An NOx storage material including a composite oxide of silver and gallium. The composite oxide of silver and gallium is preferably a delafossite-type composite oxide. The composite oxide is produced by dissolving a silver salt and a gallium salt in a solvent and baking the solution, wherein the molar ratio of silver:gallium is preferably from 2:8 to 7:3.

Abstract: Provided are an exhaust gas purification catalyst comprising a nanocomposite material comprising CeO2 and NiO which are uniformly mixed; and a production method thereof. The uniform mixing satisfies at least one of following conditions: (a) when the nanocomposite material is analyzed using STEM-EDX, the number of Ni atoms is from 3 to 20 atomic % relative to the total number of Ni and Ce atoms at a majority of randomly selected 5 or more measurement points in which both Ce and Ni elements are detected; and (b) in the Fourier transform of EXAFS spectrum at Ni—K absorption edge regarding the nanocomposite material, the ratio of the peak intensity of Ni—O near an interatomic distance of 1.8 ? to the peak intensity of Ni—Ni near an interatomic distance of 2.6 ? is 1:at least 0.50 to less than 2.18.

Abstract: An exhaust gas purification catalyst of the present invention includes a catalyst support and a plurality of bimetallic particles supported thereon wherein the bimetallic particles consist of gold and cobalt and have an average particle size of greater than 0 nm but 100 nm or less. A method of the present invention includes heating a mixed solution containing a gold salt, a cobalt salt, a solvent and an inorganic reducing agent to a temperature sufficient to reduce gold and cobalt, thereby producing bimetallic particles consisting of gold and cobalt, and supporting the produced bimetallic particles on the catalyst support.

Abstract: Provided are metal particles comprising an at least partial solid solution of rhodium and gold. Also provided is a method for producing metal particles comprising adding a boron-based reducing agent to a mixed solution containing a rhodium salt and a gold salt to produce the metal particles comprising an at least partial solid solution of rhodium and gold. Furthermore, provided are an exhaust gas purifying catalyst comprising the metal particles supported on a catalyst support and a method for producing the same.

Abstract: The purpose of the present invention is to provide an exhaust gas purification catalyst which can decrease a NOx reduction temperature and comprises rhodium and gold. An exhaust gas purification catalyst which carries two-element microparticles each comprising rhodium and gold, said catalyst being characterized in that the rhodium and the gold are phase-separated from each other and the content ratio of the rhodium to the gold (i.e., rhodium:gold) is (30-99.9 at. %):(70-0.1 at. %) in the two-element microparticles.

Abstract: An exhaust gas purification catalyst of the present invention includes a catalyst support and a plurality of bimetallic particles supported thereon wherein the bimetallic particles consist of gold and cobalt and have an average particle size of greater than 0 nm but 100 nm or less. A method of the present invention includes heating a mixed solution containing a gold salt, a cobalt salt, a solvent and an inorganic reducing agent to a temperature sufficient to reduce gold and cobalt, thereby producing bimetallic particles consisting of gold and cobalt, and supporting the produced bimetallic particles on the catalyst support.

Abstract: An exhaust gas purification catalyst for removing CO or HC, which contains a carrier and an alloy of palladium and silver supported on this carrier.

Abstract: The purpose of the present invention is to provide an exhaust gas purification catalyst which can decrease a NOx reduction temperature and comprises rhodium and gold. An exhaust gas purification catalyst which carries two-element microparticles each comprising rhodium and gold, said catalyst being characterized in that the rhodium and the gold are phase-separated from each other and the content ratio of the rhodium to the gold (i.e., rhodium:gold) is (30-99.9 at. %):(70-0.1 at. %) in the two-element microparticles.

Abstract: Provided are metal particles comprising an at least partial solid solution of rhodium and gold. Also provided is a method for producing metal particles comprising adding a boron-based reducing agent to a mixed solution containing a rhodium salt and a gold salt to produce the metal particles comprising an at least partial solid solution of rhodium and gold. Furthermore, provided are an exhaust gas purifying catalyst comprising the metal particles supported on a catalyst support and a method for producing the same.

Abstract: The present invention relates to a catalyst for purification of nitrogen oxides, the catalyst comprising a solid in which Au and Fe atoms exist in a state of being close. In accordance with the present invention, a catalyst that can demonstrate NOx purification performance at low temperatures and/or in an oxidative atmosphere is provided.

Abstract: An exhaust gas purification catalyst for removing CO or HC, which contains a carrier and an alloy of palladium and silver supported on this carrier.