MeOx/Al2O3 and MeOx/CeO2 (Me = Fe, Co, Ni) catalysts for high temperature N2O decomposition and NH3 oxidation

Abstract

A series of MeOx/Al2O3 and MeOx/CeO2 (Me = Fe, Co, Ni) compounds was prepared by incipient wetness impregnation and characterized by XRD, XPS, UV-vis DRS, differential dissolution phase analysis (DDPA). Their activity towards N2O decomposition and ammonia oxidation at 750-900 °C was shown to depend on oxygen mobility in the sample as characterized by steady state isotopic transient kinetic analysis (18O SSITKA) and dispersion of MeOx (Me = Fe) species. Obvious reverse "activity-FeOx dispersion" dependence was related to the change of contribution from oxygen transfer from the support to active sites through the Me-ceria or not improbably, the Me-alumina interface. It was shown that the high efficiency of CeO2 based samples in deN2O can be additionally increased by CeO2 supporting onto high surface area alumina.