The mechanism of low-temperature ammonia oxidation on metal oxides according to the data of spectrokinetic measurements

Low temperature ammonia oxidation on MoO3, Fe2O3, Cr2O3, and ZnO is studied by the spectro-kinetic method. It is shown that the following adsorbed species are intermediates in this reaction: NH3 and N2O on Fe2O3 and ZnO; NH3, N2O, and NO on Cr2O3. All of the detected intermediates are used to construct the mechanism of the process. In the framework of the proposed mechanism, stationary and nonstationary spectral and kinetic data are quantitatively processed. The dependence of the rate constants of the same steps on different oxides on their physicochemical properties is discussed.