Experimental study of the SO2 removal over a NOx trap catalyst

The NOx storage capacity of a NOx trap catalyst is affected by SO2 poisoning. When the extent of poisoning is low (less than 30% of BaO involved in sulphate formation), it is possible to regenerate the catalyst under reducing conditions and the initial storage capacity can be recovered, even in the presence of some remaining sulphates. When the extent of poisoning is very high, it is more difficult to regenerate the material and the initial NO, storage capacity cannot be recovered, even after long regeneration duration. (C) 2002 Elsevier Science B.V. All rights reserved.