EXHAUST PURIFICATION DEVICE FOR INTERNAL COMBUSTION ENGINE

摘要

The objective of the present invention is to suppress the deterioration of an oxidizer or reducer addition device provided to an exhaust pathway in order to supply an oxidizer or reducer to a selective reduction NOx catalyst. In the exhaust pathway (2) of an internal combustion engine (1), a first selective reduction NOx catalyst (3) and a second selective reduction NOx catalyst (4) are provided in sequence from the upstream side along the flow of exhaust. Also, the addition device (5) is provided between the first selective reduction NOx catalyst (3) and the second selective reduction NOx catalyst (4).