Catalytic convertor for removing nitrogen oxides from the exhaust gas of diesel motors

摘要

Catalyst comprising a support body of length L and a catalytically active coating of one or more material zones: a zeolite or a zeolite-like compound containing 1-10 wt.% of copper, where the zeolite or the zeolite-like compound is chabazite, SAPO-34, ALPO-34 or zeolite-beta ; and at least one compound (A) comprising barium oxide, barium hydroxide, barium carbonate, strontium oxide, strontium hydroxide, strontium carbonate, praseodymium oxide, lanthanum oxide, magnesium oxide, magnesium/aluminum-mixed oxide, alkali metal oxide, alkali metal hydroxide and/or alkali metal carbonate, is new. Independent claims are included for: (1) removing nitrogen oxides from the exhaust gas of diesel engines, comprising conducting the exhaust gas to be purified exhibiting an air ratio lambda , which is greater than 1, over the catalyst; and (2) an apparatus for performing the method, comprising the catalyst and a selective catalytic reduction catalyst arranged downstream to it.