| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an exhaust emission control system of internal combustion engines which well achieves both adsorbing efficiency and eliminating efficiency of non-purified ingredients inside an emission passage of an exhaust emission control system that has an adsorbent therein. <P>SOLUTION: An exhaust emission control system of internal combustion engines comprises: a bypass 20 branched from an emission passage 14; a switching valve 22 switching over an exhaust gas flow destination between the emission passage 14 and the bypass 20; an NOx adsorbent 24 adsorbing NOx in the emission, the NOx adsorbent 24 being disposed in the bypass 20; and a catalyst 26 disposed at the upstream of the NOx adsorbent 24 in the bypass 22, wherein the amounts of emission reducing agent and oxidizing agent fed into the catalyst 26 are increased when NOx adsorbed into the NOx adsorbent is eliminated at the time of cold start.Preferably, an air-oil ratio in the internal combustion engine is enriched and air is introduced into the catalyst 26 as well. <P>COPYRIGHT: (C)2009,JPO&INPIT |
