| 摘要 |
PURPOSE:To improve the durability of the title catalyst and to enhance the activity at low temp. by depositing the catalyst composition consisting of the fine particles of zirconia carrying Pt and/or Pd and Rh on a honeycomb carrier to form the catalyst. CONSTITUTION:Granular zirconia is immersed in an aq. soln. of the salts of Pt and/or Pd and Rh, and then dried and baked to obtain the zirconia carrying 5-30wt.% Pt and/or Pd and 1-20wt.% Rh. The obtained zirconia is crushed by a mill, etc., to 0.1-20mu particle diameter, and then slurred. The slurry is wash-coated on a monolithic honeycomb carrier, dried, and then baked, as required, to produce the catalyst for purifying exhaust gas. Besides, a refractory inorg. oxide such as activated alumina can be appropriately added to the noble metal-carrying zirconia, and jointly used. |
