| 摘要 |
<P>PROBLEM TO BE SOLVED: To suppress a decrease in the NO<SB>x</SB>reducing performance of a NO<SB>x</SB>storage reduction catalyst used in an exhaust emission control device. <P>SOLUTION: In this exhaust emission control device 10, when it is determined that the NO<SB>x</SB>storage reduction catalyst 16 is poisoned with hydrocarbon (HC) by performing NO<SB>x</SB>storage reduction catalyst purifying treatment, HC purge treatment for removing the HC according to the NO<SB>x</SB>storage capacity of the NO<SB>x</SB>storage reduction catalyst 16 is performed. After that, NO<SB>x</SB>reducing treatment for enriching an air-fuel ratio of exhaust gas is performed. <P>COPYRIGHT: (C)2010,JPO&INPIT |
