EXHAUST GAS CLEANING DEVICE

摘要

PROBLEM TO BE SOLVED: To clean NOx by forming oxygen-containing hydrocarbon species high in reactivity to the NOx from an exhaust gas containing a reducing agent and also allowing the oxygen-containing hydrocarbon species to react with the NOx. SOLUTION: This device is constituted of a partial oxidation catalyst 1 obtd. by supporting transition metal elements on a porous carrier and an NOx reducing catalyst 2 obtd. by supporting noble metals on a porous carrier. A hydrocarbon component in the exhaust gas is partially oxidized with the partial oxidation catalyst 1 and reformed to an oxygen-containing hydrocarbon compound. The oxygen-containing hydrocarbon compound has high reactivity with the NOx and reacts with the NOx on a surface of the NOx reducing catalyst 2 to reduce and clean the NOx, thus high NOx cleaning performance is attained even in a low temp. region.