An investigation on catalytic performance and reaction mechanisms of Fe/OMS-2 for the oxidation of carbon monoxide, ethyl acetate, and toluene

Abstract

The octahedral molecular sieve (OMS-2)-supported Fe (xFe/OMS-2: x = 1, 3, 5, and 10) catalysts were prepared using the pre-incorporation method. Physicochemical properties of the as-synthesized materials were characterized by means of various techniques, and their catalytic activities for CO, ethyl acetate, and toluene oxidation were evaluated. Among all of the samples, performed the best, with the reaction temperature required to achieve 90% conversion (T90%) being 160°C for CO oxidation, 210°C for ethyl acetate oxidation, and 285°C for toluene oxidation. Such a good catalytic performance of 5Fe/OMS-2 was associated with its high (Mn3+ + Mn2+) content and adsorbed oxygen species concentration, and good low-temperature reducibility and lattice oxygen mobility as well as strong interaction between Fe and OMS-2. In addition, catalytic mechanisms of the oxidation of three pollutants over the 5Fe/OMS-2 catalyst were also studied. It was found that CO, ethyl acetate or toluene was first adsorbed, then the related intermediates were formed, and finally the formed intermediates were completely converted into CO2 and H2O.