Application, Characterization, and Simulation of CuO-ZnO-TiO2 for Catalytic Oxidation of Cumene to Cumene Hydroperoxide

Abstract

CuO-ZnO-TiO₂ was prepared by ultrasound-assisted coprecipitation. Its catalytic performance in the liquid-phase oxidation of cumene with oxygen to cumene hydroperoxide (CHP) was studied. Under the reaction conditions of CuO:ZnO:TiO₂ molar ratio of 3:1:1.33, feed ratio (catalyst/cumene) of 7.5 mg/mL, reaction temperature of 85 °C, reaction time of 7 h, and oxygen flow rate of 15 mL/min, the conversion of cumene was 37.2% and the selectivity of CHP was 94.5%. Characterization by XRD, SEM, TEM, EDS, and N₂ adsorption/desorption showed 3CuO-ZnO-TiO₂ was concentrated with a particle size of about 50 nm, specific area of about 110 m²/g with a pore volume of 0.0048 cm³/g, and high dispersion of active components. XPS and O₂-TPD characterization indicated that 3CuO-ZnO-TiO₂ contains a large amount of lattice oxygen and reactive oxygen species. DFT simulation indicated ROO· is more easily generated and more likely to bind to the CuO-ZnO surface to facilitate oxidation of cumene to cumene peroxides.