| 摘要 |
PROBLEM TO BE SOLVED: To more enhance poisoning resistance against sulfur of an NOx occluding/reducing catalyst for cleaning exhaust gas and to more enhance its NOx cleaning performance after an endurance running. SOLUTION: This NOx occluding/reducing catalyst consists of a carrier of porous oxide and a noble metal and an NOx occluding material which are deposited on the carrier. At least one selected from SnO2, Nb2O5 and Ta2O5 is furthermore incorporated in the carrier, by the presence of which sulfate in the NOx occluding material is decomposed rapidly from a low temperature region. As a result, the original NOx occluding capacity of the NOx occluding material is recovered and the catalyst has excellent NOx occluding capacity even after the endurance running. |
