The Preparation, Characterization And The Mechanism Study Of CO Oxidation Over MnO_X Combustion Catalyst

Mn3O4nanoparticles was prepared using Mn(Ac)2·4H2O as the precursor and oleic acid as the protector through the mathol thermal. Mn2O3can be obtained by calcination of directly. Mn3O4nanoparticle can also be the core of Mn3O4@SiO2. Mn2O3was found to be active for CO oxidation. The activity for Mn3O4@SiO2is decreased but showed good stabilitiy in the same condition. With the combination of the temperature-programmed desorption of O2(O2-TPD), temperature-programmed surface reaction (TRSR) of CO oxidation, Operando Raman spectra and kinetics parameters, we conclude that the oxidizing of CO may proceed through the Langmuir-Hinshelwood mechanism (<200℃) to Mars-van-Krevelen mechanism (>350℃) with the increasing of reaction temperature. In particular, the adsorbed oxygen is deduced to be responsible for CO oxidation at lower temperatures, while Mn3O4@SiO2is Langmuir-Hinshelwood machemism from200-300℃.