| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an exhaust emission control device of an internal combustion engine capable of restraining discharge of H<SB>2</SB>S even when a concentration detecting means is abnormal by accurately detecting the concentration of the H<SB>2</SB>S and SOx. <P>SOLUTION: This exhaust emission control device is provided with a storage-reduction type NOx catalyst 8 arranged in an exhaust passage 4 of the internal combustion engine 1, a concentration detecting means 10 capable of respectively detecting the total concentration of sulfur oxides and hydrogen sulfide in exhaust gas passing through the NOx catalyst and the concentration of the sulfur oxides, a poisoning recovery control means 15 capable of performing S poisoning recovery processing for controlling an operation state of the internal combustion engine so that the sulfur oxides are discharged from the NOx catalyst, and a zero point correcting means 15 for correcting a zero point of the concentration detecting means when determining that the exhaust gas passing through the NOx catalyst is a zero point correcting state capable of correcting the zero point of the concentration detecting means. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
