| 摘要 |
PURPOSE:To improve oxidation resistance and peeling resistance by providing the layer of perovskite type oxides having a specified metallic composition to the inflow port side of exhaust gas on a base body made of heat resistant steel and providing an activated alumina layer carried with catalytic metal thereon. CONSTITUTION:A cylindrical body 5 molded by alternately winding corrugated sheets 6 and plates 7 is immersed into the aq. soln. of rare earth metallic salt having 3 valence in a range to the central part of the base part from the inflow port side of exhaust gas and thereafter it is dried at about 200 deg.C for about 2hr. Then the outlet side of exhaust gas in the reaction side is immersed into the aq. soln. of alkaline earth metallic salt and calcined at 700 deg.C to form an oxide layer 2. Then the base body 1 is immersed into slurry consisting of activated alumina, a binder and water, and calcined at about 600 deg.C to form a layer 3 carried with activated alumina. Furthermore the base body 1 is successively immersed into a platinum amine aq. soln. and a rhodium chloride aq. soln. and a catalyst for purifying exhaust gas is obtained by carrying catalytic metal 4 thereon. |
