| 摘要 |
PROBLEM TO BE SOLVED: To provide an exhaust emission purifier capable of surely combusting and purifying HC generated in cold starting an internal combustion engine. SOLUTION: Two adsorption catalyst devices 3, 4 respectively provided with a ternary catalyst 5, 7 and an HC adsorbent 6, 8, are mounted on an exhaust passages 2 in series, and a ratio of the ternary catalyst 5 is high at an inlet side in the upstream-side adsorption catalyst device 3, and a ratio of the HC adsorbent 8 is high at an inlet side in the downstream-side adsorption catalyst device 4 to early activate the ternary catalyst 5 of the upstream-side adsorption catalyst device 3 in cold starting. HC generated before the activation of the ternary catalyst 5 is efficiently adsorbed by the HC adsorbent 6 of the adsorption catalyst device 3, and then the HC separated from the HC adsorbent is surely adsorbed again by the HC adsorbent 8 in the downstream-side adsorption catalyst device 4, whereby the HC is surely combusted and purified by the ternary catalyst 7 of an active temperature. |
