| 摘要 |
PURPOSE:To raise oxidation resistance and catalytic activity by allowing a catalytic metal to be carried by at least an active alumina-carrying layer out of a layer of oxides of Zr and Si and the active alumina-carrying layer, both layer having been provided on a substrate, thereby preparing a catalyst for purification of exhaust gases. CONSTITUTION:A substrate made of heat-resistant steel is heat-treated, with Zr and silicon present on surfaces of the substrate, thereby forming an oxide layer on the surfaces of the substrate. Further, a catalytic metal is carried by at least an active alumina-carrying layer out of the oxide layer and the active alumina-carrying layer. Thus, a catalyst for purification of exhaust gases is formed. More particularly, the catalyst for purification of exhaust gases is constituted by a cylindrical honeycomb substrate 1 consisting of predetermined components, an oxide layer 2 formed on surfaces of the substrate, an active alumina-carrying layer 3 formed on the layer 2, and a catalytic metal 4 carried mainly by the active alumina-carrying layer 3. |
