EXHAUST CLEANING DEVICE FOR DIESEL ENGINE

摘要

PROBLEM TO BE SOLVED: To simultaneously remove nitrogen oxide(NOx) and granular substances (PM) included in exhaust gases. SOLUTION: Filters 14 to be interposed into an exhaust passage 10 for a diesel engine in order to capture the granular substances included in the exhaust gases is coated with first catalysts which are platinum-deposited oxide catalysts to oxidize carbon monoxide like '2NO+O2→N2+2CO2' and second catalysts which are rhodium-deposited oxide catalysts or iridium oxide catalysts to react the carbon monoxide and nitrogen monoxide like '2CO+2O2→N2+2CO2', by which the exhaust emission control device for the diesel engine is constituted. The filters 14 may be additionally coated with the third catalysts which are multicomponent oxide catalysts to successively react nitrogen dioxide and nitrogen monoxide with the granular substances captured by the filters like '2 NO2+C→2NO+CO2, 2NO+C→N2+CO2' in order further to perform emission control.