| 摘要 |
PURPOSE:To prevent a catalyst from being covered by Pb and to improve durability of catalyst against poisoning due to Pb by providing a layer of activated aluminal activated by aluminum sulphate on the surface of catalyst carrier and trapping Pb compd. in the exhaust gas by trapping Pb compd. in the exhaust gas by the layer of activated alumina. CONSTITUTION:In a catalyst for purifying exhaust gas comprising a catalyst carrier and catalyst metal supported by the carrier, said catalyst carrier is formed at least of the surfacial alumina layer, and aluminum sulphate is made to contain alumina layer at least in its surface layer. Preferred catalyst carrier is monolithic catalyst carrier of cordierite or granular carrier. As the result, Pb compd. in the exhaust gas is trapped by the activated alumina layer, and the catalyst metal is prevented from being covered by Pb. Thus, durability of catalyst is improved and the catalyst is prevented from being poisoned by the Pb compd. |
