| 摘要 |
PURPOSE:To enhance the catalytic activity and durability of the title catalyst by depositing at least one kind between platinum and rhodium in an alumina coating layer contg. praseodymium, cerium, and activated alumina to form the catalyst for purifying exhaust gas. CONSTITUTION:The activated alumina carrier is impregnated with a specified amt. of an aq. soln. of cerium nitrate contg. praseodymium, dried, and then baked at 600-650 deg.C for 1.5-2hr in the air to obtain activated alumina deposited with praseodymium and ceria. The activated alumina and ceria powder carrying praseodymium are mixed and crushed in a nitric acid-acidified boehmite alumina sol to obtain a slurry. The obtained slurry is coated on the surface of a cordierite monolithic carrier base material. The material is dried, and then baked in the air at 650-850 deg.C to obtain a catalyst carrier. The catalyst carrier is dipped in an aq. soln. of a platinum salt and a rhodium salt to deposit >=1 kind between platinum and rhodium on the carrier. |
