EXHAUST EMISSION CONTROL DEVICE

摘要

PROBLEM TO BE SOLVED: To inhibit the emission control efficiency of a NOx selective reduction catalyst 9 from deteriorating by catalytic metal for oxidation separated from an oxidation catalyst 7 and a particulate filter 8.SOLUTION: An auxiliary agent comprising at least one selected from alkali metal, alkaline earth metal, sulfur and phosphor is carried on at least a part of portions contacting with exhaust gas between a reducing agent supply 5 and the NOx selective reduction catalyst 9 or at a part on an upstream side in an exhaust gas flow in the NOx selective reduction catalyst 9.