CATALYTIC REDUCTION OF NITRIC OXIDE WITH AMMONIA OVER TRANSITION METAL ION-EXCHANGED Y ZEOLITES

Abstract Catalytic reduction of nitric oxide with ammonia was studied over transition metal ion-exchanged Y zeolite (Me-Y) catalysts. Among various catalysts used, Cu(II)–Y was found to be of particular interest, exhibiting low temperature activity and an unusual catalytic activity-temperature profile with a maximum at 120°C. It was also observed that the catalytic activity was enhanced considerably when a second cation, especially Co (II) or Fe(III), was co-exchanged together with Cu(II) in Y zeolite. Such phenomena were discussed briefly.