초록 ▼

The invention concerns a catalyst for oxidation of hydrocarbons and carbon monoxide and/or reduction of nitrogen oxides. The catalyst consists of a carrier body and on this a catalytical coating, which consists of a washcoat layer containing a support material with a high specific surface area, one

The invention concerns a catalyst for oxidation of hydrocarbons and carbon monoxide and/or reduction of nitrogen oxides. The catalyst consists of a carrier body and on this a catalytical coating, which consists of a washcoat layer containing a support material with a high specific surface area, one or more metal oxides with a promoting effect and at least two catalytically active noble metals within the washcoat or on the washcoat. The catalytical coating consists of at least two washcoat layers containing different amounts of at least one noble metal, in such a way that at least one noble metal is concentrated to more than 50% by weight of its total amount to at least one of the layers and that at least two noble metals are contained together in at least one of the layers. The invention also concerns a process for the preparation of said catalyst in order to obtain said layers with different composition of noble metals. The invention also concerns the use of said catalyst for purification of exhaust gases from internal combustion engines.

대표청구항 ▼

A catalyst for treating a gas flow for the oxidation of hydrocarbons and carbon monoxide and/or the reduction of nitrogen oxides comprising a carrier body and a catalytic coating, said coating comprising at least two washcoat layers applied parallel to the gas flow, each washcoat layer comprising a

A catalyst for treating a gas flow for the oxidation of hydrocarbons and carbon monoxide and/or the reduction of nitrogen oxides comprising a carrier body and a catalytic coating, said coating comprising at least two washcoat layers applied parallel to the gas flow, each washcoat layer comprising a support material having a high surface area and one or more metal oxide promoters and one layer containing at least one catalytically active noble metal, the amount of said at least one catalytically active noble metal being different in each washcoat layer with more than 50% by weight of the total amount of said at least one catalytically active noble metal being contained in one said layer and further wherein at least one layer contains at least two catalytically active noble metals.