Mesoporous Co3O4 catalysts for VOC elimination: Oxidation of 2-propanol

Mesoporous cobalt oxides were prepared by an inverse micelle method and calcined at different temperatures. These materials exhibited superior activity for oxidation of 2-propanol as the model substrate for VOC elimination. Highest active Co3O4-350 material showed a maximum turnover frequency of 25.8 h(-1) at 160 degrees C at a weight hourly space velocity of 60 L g(-1) h(-1). The apparent activation energies of mesoporous cobalt oxides ranged from 69.7 kJ/mol to 115.6 kJ/mol. In situ Diffuse Reflectance Infrared spectroscopy (DRIFTS) revealed that the reaction involves formation of carbonyl and carbonate species on the surface of the catalyst before complete oxidation to CO2 and H2O. The activities of the materials were correlated to better low temperature reducibility, large pore volumes, higher Co3+/Co2+ ratios, and higher number of surface-active oxygen species.