Selective oxidation of ammonia to nitrogen on transition metal containing mixed metal oxides

Abstract The selective catalytic oxidation of ammonia to nitrogen (NH 3 -SCO) has been studied over hydrotalcite derived mixed metal oxides containing Cu, Co, Fe or Ni. XRD, BET, NH 3 -TPD and TPR techniques were used for catalysts characterization. Results of NH 3 -SCO were compared with those of selective catalytic reduction of NO with NH 3 (NO-SCR). Reaction mechanism was studied by temperature-programmed surface reaction (TPSR) and activity tests with a various contact time. Catalytic performance of the studied samples depends on both kind and loading of transition metals in the mixed metal oxide system. The Cu-containing samples have been found to be the most active catalysts of the NH 3 -SCO process. Transition metal loading strongly influences distribution of ammonia oxidation products. The highest selectivity to N 2 was measured for the catalysts with the lowest transition metal content.