Process for reducing nitrogen oxides from exhaust gas
AssigneesTosoh Corporation, Kabushiki Kaisha Toyota Chuo Kenkyusho, Toyota Jidosha Kabushiki Kaisha
InventorsSenshi Kasahara, Katsumi Kamiyama, Kazushige Igawa, Shinichi Matsumoto, Masayuki Fukui, Tadashi Suzuki, Shiroh Kondoh, Koji Yokota, Shinichi Takeshima, Kazunobu Ishibashi, Masao Nakano
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Abstract
A catalyst for reducing nitrogen oxides from an exhaust gas containing the same in an oxygen rich atmosphere comprising (i) a zeolite having a molar ratio of SiO.sub.2 /Al.sub.2 O.sub.3 of at least 10, (ii) copper, and (iii) a rare earth ion, an alkaline earth metal and/or a valence variable metal.
Claims13
A method of purifying an exhaust gas containing an excess amount of oxygen, which comprises bringing a catalyst into contact with the exhaust gas to remove nitrogen oxides, carbon monoxide and hydrocarbons from the exhaust gas, the catalyst comprising:
- (i) a zeolite having a molar ratio of SiO.sub.2 /Al.sub.2 O.sub.3 of at least 10;
- and
- (ii) at least one copper ion and at least one kind of rare earth ion loaded thereon.
A method of purifying an exhaust gas containing an excess amount of oxygen, which comprises bringing a catalyst into contact with the exhaust gas in the presence of an organic compound to remove nitrogen oxides, carbon monoxide and hydrocarbons from the exhaust gas, the catalyst comprising:
- (i) a zeolite having a molar ratio of SiO.sub.2 /Al.sub.2 O.sub.3 of at least 10;
- and
- (ii) at least one copper ion and at least one kind of alkaline earth metal loaded thereon.
A method of purifying an exhaust gas containing an excess amount of oxygen, which comprises bringing a catalyst into contact with the exhaust gas in the presence of an organic compound to remove nitrogen oxides, carbon monoxide and hydrocarbons from an exhaust gas, the catalyst comprising:
- (i) a zeolite having a molar ratio of SiO.sub.2 /Al.sub.2 O.sub.3 of at least 10;
- and
- (ii) at least one copper ion and at least one kind of valence variable metal loaded thereon.
Dependencies are inferred from the claim text.