Catalyst useful for removing nitrogen oxide from an exhaust gas of diesel engine comprises a carrier body of length (L) and a catalytically active coating made of at least one material zone

摘要

Catalyst comprises a carrier body of length (L) and a catalytically active coating (3) made of at least one material zone (3a, 3b) comprising (i) at least one of (a) zeolite containing copper, iron and/or silver, (b) titanium dioxide, zirconium oxide, vanadium oxide, tungsten oxide and/or silicon dioxide, (c) cerium oxide, zirconium oxide, neodymium oxide, tungsten oxide, iron oxide, lanthanum oxide, praseodymium oxide and/or aluminum oxide, or (d) mixtures of (a), (b) and/or (c), and (ii) at least one of e.g. barium oxide, barium hydroxide, barium carbonate or strontium oxide. Catalyst comprises a carrier body of length (L) and a catalytically active coating (3) made of at least one material zone (3a, 3b) comprising (i) at least one of (a) zeolite containing 1-10 wt.% of copper, iron and/or silver, based on the total weight of the zeolite, where the zeolite comprises zeolite beta , mordenite (MOR), ultrastable Y (USY), zeolite Socony Mobil-5 (ZSM-5), ferrierite (FER) and/or chabazite (CHA), (b) titanium dioxide, zirconium oxide, vanadium oxide, tungsten oxide and/or silicon dioxide, (c) cerium oxide, zirconium oxide, neodymium oxide, tungsten oxide, iron oxide, lanthanum oxide, praseodymium oxide and/or aluminum oxide, or (d) mixtures of (a), (b) and/or (c), and (ii) at least one of barium oxide, barium hydroxide, barium carbonate, strontium oxide, strontium hydroxide, strontium carbonate, praseodymium oxide, lanthanum oxide, cerium oxide, cerium/zirconium mixed oxide, magnesium oxide, magnesium/ aluminum mixed oxide, alkali metal oxide, alkali metal hydroxide and/or alkali metal carbonate. Independent claims are also included for: (1) removing nitrogen oxides from the exhaust gas of the diesel engine, comprising passing to be cleaned exhaust gas with an air ratio lambda , which is greater than 1, over the catalyst; and (2) a device for carrying out the above mentioned method comprising the catalyst and a selective catalytic reduction (SCR)-catalyst arranged at its outflow side.