Epoxidation of cyclohexene with tert-butyl hydroperoxide catalyzed by mixed oxide V2O5-TiO2

TiO2 and 20 wt% V2O5-TiO2 catalysts were prepared by the sol-gel route and calcined at 500 degrees C. The mixed oxide presented the crystalline structures of TiO2 anatase and V2O5 Shcherbinaite phases, with a BET (Brunauer-Emmett-Teller) surface area of 19 m(2)/g. The catalytic material was tested for the epoxidation of cyclohexene by tert-butyl hydroperoxide at 80 degrees C. The activity and selectivity were investigated as a function of the reaction time as well as the amounts of the catalyst and solvent. The reaction followed second-order kinetics, and the best catalytic performance was observed after 6 hr of reaction time, with 150 mg of catalyst in n-heptane solvent. The epoxidation selectivity reached 76% at 48% conversion. The catalyst remained stable after two cycles.