EXHAUST GAS CLEANING DEVICE

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PROBLEM TO BE SOLVED : To upgrade cleaning performance at a low temperature of PM, HC and NOx by supplying a large quantity of NO2 to an NOx occlusion reduction catalyst etc. disposed downstream from an oxidation catalyst 1. SOLUTION : The oxidation catalyst 1 comprises a first catalytic layer 11 containing no zeolite, a second catalytic layer 12 which contains zeolite but not a rare metal or contains a negligible amount of rare metal, and a third catalytic layer 13 containing a rare metal. As the chemical reaction to reduce NO2 to NO is inhibited in the first catalytic layer 11, it is possible to supply a large amount of NO2 to the NOx occlusion reduction catalyst etc. disposed downstream. COPYRIGHT : (C)2010, JPO&INPIT