| 摘要 |
<P>PROBLEM TO BE SOLVED: To properly set regeneration time for an NOx storage catalyst in relation to an exhaust emission control device for an internal combustion engine. <P>SOLUTION: A reforming catalyst 13 is disposed in an engine exhaust passage, and downstream of the reforming catalyst 13, the NOx storage catalyst 15 is disposed to store NOx when an air-fuel ratio is lean, and emit stored NOx when the air-fuel ratio is rich. Relation between necessary regeneration time for regenerating the NOx storage catalyst 15 and exhaust gas quantity is preliminarily determined. An SOx emission process from the NOx storage catalyst 15 is executed through a regeneration period determined based on the relation. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
