NH3 oxidation to nitrogen and water at low temperatures using supported transition metal catalysts, revised manuscript ISO 71

The ability of several alumina-supported metal catalysts and transition-metal ion-exchanged zeolite Y catalysts to oxidize ammonia to nitrogen and water at low temperatures (between 200 and 350 degrees C) was tested both at high and low ammonia concentrations. Copper-containing zeolite Y catalysts were comparable in activity and were more selective than noble-metal containing zeolite catalysts of similar metal loading. Cu/zeolite-Y catalysts were superior to copper/molybdenum and vanadium/alumina catalysts. Postsynthesis treatment of Cu/zeolite-Y with NaOH increased the activity for ammonia oxidation; dispersion and size of the supported copper-oxide particles were very important parameters. Go-fed steam dramatically increased the deactivation on all catalysts, especially at lower temperatures. (C) 2000 Published by Elsevier Science B.V