| 摘要 |
PURPOSE:To purify NOx by a Pt type catalyst without forming N2O. CONSTITUTION:A Rh or Pd type catalyst or a Ph/Pd mixed catalyst 10 is arranged to the front stage of the exhaust system 4 of an internal combustion engine 2 and a Pt type catalyst 8 is arranged to the rear stage of said exhaust system to constitute the, purifier of the internal combustion engine. CO is oxidized by the catalyst 10 of the front stage and the max. purifying activity temp. of NOx due to the Pt type catalyst 8 in such a case that CO is absent is higher than that in such a case that CO is present and, therefore, N2O is hard to generate. |
