| 摘要 |
PURPOSE: To obtain a composite catalyst promoting the oxidation-reduction reactions of exhaust gases produced by an internal combustion engine, to provide a method for producing the catalyst and to provide a method for reducing contaminating exhaust materials by using the catalyst. CONSTITUTION: The present invention relates to a catalyst comprising tungsten oxide, a basic metal oxide, and a noble metal. More narrowly, the present invention relates to a catalyst comprising a refractory inorganic oxide, tungsten oxide in juxtaposed relation with the refractory inorganic oxide, and a basic metal oxide in juxtaposed relation with the tungsten oxide; and arrayed on the composite oxide a noble metal. Moreover, as to the catalyst, the ratio of the tungsten oxide to the basic metal oxide is (1:30) to (10:1). |
