High performance BaCO3-CeO2 composite catalyst for solvent-free selective oxidation of cyclohexane with molecular oxygen

Abstract

BaCO3-CeO2 composite catalysts were prepared by the hydrothermal synthesis method, and the influence of Ba/Ce on the structural and catalytic performance for selective oxidation of cyclohexane with molecule oxygen was studied. The characterization results exhibited that the doping amount of BaCO3 would influence the morphology, the content of surface Ce3+ and surface oxygen species (Oβ), and alkalinity. Meanwhile, the amount of alkali is the key to the decomposition of cyclohexyl hydrogen peroxide (CHHP). 10.5% conversion of cyclohexane and 85.0% selectivity of KA oil were achieved under the reaction conditions of 1.0 MPa O2 and 150 °C for 2 h. The excellent catalytic activity was attributed to its high atomic ratios of Ce3+/Cetotal and Oβ/Ototal on the surface and optimal redox capacity.