N_2O decomposition in the presence of ammonia on faujasite-supported metal catalysts

摘要

The reduction of N_2O to N_2 was carried out by temperature programmed surface reaction (TPSR) from 473 to 873 K in He, He + 3% O_2, He+0.02% NH_3 and He + 3% O_2 + 0.02% NH_3 on H-FAU supported transition metal catalysts. In the absence of oxygen, the addition of NH_3 considerably shifts the N_2O conversion profile towards lower temperatures. This is particularly true for the Ru- and Rh-FAU which exhibit the onset of N_2O conversion around 500 K. The addition of O_2 inhibits this effect for most of the catalysts and NO formation due to NH_3 oxidation is observed. However Fe-, Ni- and Co-FAU kept the best catalytic behaviour for N_2O reduction to N_2 in the presence of O_2, when NH_3 was added to the feed with respect to the decomposition reaction.