A device for purifying the exhaust gas of an internal combustion engine

摘要

A device for purifying the exhaust gas of an internal combustion engine is disclosed. The device comprises a particulate filter arranged in the exhaust system, which carry a catalyst for absorbing and reducing NOx. The catalyst absorbs NOx when the air-fuel ratio in the surrounding atmosphere thereof is lean and releases the absorbed NOx to purify NOx by reduction when the air-fuel ratio is the stoichiometric or rich. The device further comprises a catalytic apparatus for purifying NOx arranged in the exhaust system upstream of the particulate filter, which has an oxidation function.