Isothermal oscillation during N2O decomposition over Fe- and Fe/Pt-ferrierite:: Effect of NO addition

Well-expressed oscillation of the N2O decomposition over Fe- and Fe/Pt-fer-rierite catalysts has been observed, differing both in parameters and conditions from the oscillation behavior described previously for the same reaction over Fe-zeolites. The observed regular oscillation in the N2O conversion was accompanied by changes in N-2 and O-2 production in a dry N2O/He gas stream and was quenched reversibly after NO/NO2 addition. The results were observed in the temperature region of 400-450 degrees C over Fe/Pt-ferrierite, with periods of 0.5-3.5 min. For Fe-ferrierite, the temperature region for the oscillation behavior was slightly higher (i.e., 450-500 degrees C. In striking contrast to Fe/Pt-fer-rierite, the period of oscillation did not change with temperature over Fe-ferrierite. The patterns of the oscillation over both catalysts were complex and depended on the reaction conditions. (c) 2006 Elsevier Inc. All rights reserved.