| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a device and a method for detecting deterioration in an NO oxidation catalyst, which easily detects deterioration in the NO oxidation catalyst. <P>SOLUTION: This device 1 for detecting deterioration in the NO oxidation catalyst 5 detects deterioration in the NO oxidation catalyst 5, and includes an execution determination means determining that deterioration determination of the NO oxidation catalyst 5 can be executed when adsorption quantity of NO<SB>2</SB>adsorbed by the NO oxidation catalyst 5 is less than saturation adsorption quantity, a flow-in side NOx concentration detection means detecting NOx concentration of exhaust gas flowing into the NO oxidation catalyst 5, a flow-out side NOx concentration detection means detecting NOx concentration of exhaust gas flowing out the NO oxidation catalyst 5, and a deterioration determination means determining that the NO oxidation catalyst 5 is deteriorated if difference resulting from subtracting a detection value of the flow out side NOx concentration detection means from a detection value of the flow in side NOx concentration detection means is not greater than a prescribed NOx concentration threshold when the execution determination means determines that deterioration determination of the NO oxidation catalyst 5 can be executed. <P>COPYRIGHT: (C)2011,JPO&INPIT |
