| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an exhaust emission control device for an internal combustion engine capable of surely treating a hydrogen sulfide. <P>SOLUTION: This exhaust emission control device for the internal combustion engine comprises a first catalyst and a second catalyst. The first catalyst is a catalyst for absorbing and deoxidizing sulfur oxides. The second catalyst is a catalyst having an oxidizing function and provided on a downstream side of the first catalyst in an exhaust passage. Further, this exhaust emission control device for the internal combustion engine comprises an adjusting means and a control means. The adjusting means is a means capable of adjusting an air-fuel ratio of exhaust gas passing through the second catalyst and the catalyst temperature of the second catalyst. The control means performs the lean control for setting exhaust gas passing through the second catalyst to a lean air-fuel ratio lower than a lean air-fuel ratio in the lean-combustion of the internal combustion engine and for raising the catalyst temperature of the second catalyst to a first predetermined temperature by using the adjusting means. By this structure, the hydrogen sulfide generated by the first catalyst can be surely oxidized to sulfur oxides by the second catalyst for discharge. <P>COPYRIGHT: (C)2009,JPO&INPIT |
