Experimental study of the SO2 removal over a NOx trap catalyst

The NO_x storage capacity of a NO_x 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_x storage capacity cannot be recovered, even after long regeneration duration.