Abstract: A process for simultaneously reducing the amounts of hydrocarbons, carbon monoxide and nitrogen oxides contained in the exhaust gas from an internal combustion engine in the exhaust gas from gasoline or diesel engines with high amounts of oxygen in the exhaust gas is disclosed. A high reductive effect towards nitrogen oxides is enabled by using a homogeneous aluminum silicate as a high surface area support material for the catalytically active components.

Abstract: An oxidative diesel control catalyst is disclosed which has a high conversion rate for hydrocarbons and carbon monoxide and an inhibited oxidation effect on nitrogen oxides and sulfur dioxides and which contains a monolithic catalyst element with throughflow passages of ceramic or metal coated with an activity-promoting dispersion coating of the fine-particle metal oxides aluminum oxide, titanium oxide, silicon oxide, zeolite or mixtures thereof as support of the catalytically active components, the active components being present in the form of platinum, palladium, rhodium and/or iridium doped with vanadium or in contact with an oxidic vanadium compound. The reduced oxidation effect on sulfur dioxide is obtained by virtue of the fact that the fine-particle metal oxides are surface-modified aluminum oxide, titanium oxide, silicon oxide, zeolite or mixtures thereof.