Exhaust gas purification apparatus for internal combustion engine

摘要

Disclosed is an exhaust gas purification apparatus having a catalyst unit (13, 503, 704) provided in an exhaust pipe of an engine (11, 501, 701) and an absorbent (19, 505) provided downstream of the catalyst unit. When the engine is in a cool state, HC emitted from the engine is absorbed by the absorbent and the absorbed HC is returned to an upstream side of the catalyst unit after the engine is warmed up to desorb the HC by heat of an exhaust gas.