| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an exhaust emission control device of an internal combustion engine capable of suppressing deterioration of NOx emission in the internal combustion engine caused by sulfur components remaining in a NOx catalyst by reducing the sulfur components always remaining in the catalyst while suppressing excessive rise of a catalyst bed temperature of the catalyst. <P>SOLUTION: High temperature S poisoning recovery control that is S poisoning recovery control at a high catalyst bed temperature higher than a catalyst bed temperature in a normal S poisoning recovery control is executed only when the amount of sulfur components always remaining in the NOx catalyst is increased, and thereby, sulfur components are efficiently discharged from the NOx catalyst. By execution of such high temperature S poisoning recovery control, the amount of sulfur components always remaining in the NOx catalyst is reduced. Accordingly, deterioration of NOx emission of the internal combustion engine caused by the remaining sulfur components can be suppressed by reducing the amount of sulfur components always remaining in the NOx catalyst while suppressing excessive rise of the catalyst bed temperature of the catalyst by execution of the high temperature S poisoning recovery control. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
