| 摘要 |
PURPOSE:To remarkably enhance the durability of the title catalyst by coating the fine particles of a catalyst composition consisting of the zirconia carrying Pt and Pd and the zirconia carrying Rh on a honeycomb carrier to form the catalyst. CONSTITUTION:Granular zirconia is immersed in an aq. soln. of a Pt salt and/or a Pd salt to prepare the zirconia A carrying 5-30wt.% Pt and/or Pd. Meanwhile, granular zirconia is dipped in an aq. soln. of a Rh salt to prepare the zirconia B carrying 1-2wt.% Rh. The zirconia A and the zirconia B are crushed by a mill, etc., to 1-20mu particle diameter, and both materials are slurred. The slurry contg. noble metals is wash-coated on a monolithic honeycomb carrier, dried, and then baked, as required, to produce the catalyst for purifying exhaust gas. |
