Oxidation of Styrene to Benzaldehyde by Anhydrous Hydrogen Peroxide on γ-Alumina-Supported V2O5 Nanoparticle Catalysts: Optimization Studies Using Response Surface Methodology

Particles of γ‐alumina‐supported V2O5 with an average particle size of 5‐10 nm and a surface area of 174.8 m2/g were prepared through a wet impregnation method. These materials were found to be effective in the selective oxidation of styrene to benzaldehyde using anhydrous H2O2. Response surface methodology was used to investigate the effect of the oxidant (H2O2) concentration (from 20 to 60 mmol), temperature (from 45 to 75°C), time (from 2.5 to 6 h) and catalyst concentration (from 0.014 to 0.036 g/L) on the styrene conversion and the selectivity of benzaldehyde and styrene oxide. Based on the response surface methodology analysis, the optimal oxidation conditions occur with a reaction temperature of 62.7°C, a reaction time of 5.15 h, a molar ratio of H2O2/styrene of 2.7:1 and a catalyst concentration of 0.024 g/L. These conditions result in maximal styrene conversion (68.23%) and benzaldehyde selectivity (57.32%).