Mechanism and kinetics of the aerobic oxidation of benzyl alcohol to benzaldehyde catalyzed by cobalt porphyrin in a membrane microchannel reactor

The highly efficient selective aerobic oxidation of benzyl alcohol to benzaldehyde catalyzed by cobalt porphyrin was achieved in a membrane microchannel reactor. The efficiency of benzyl alcohol oxidation was remarkably improved in the micro-structured chemical system, achieving a conversion and benzaldehyde selectivity of 82% and 98%, respectively, in 6.5 min. The classification and transfer of free radicals, as well as the oxygen-transfer mechanism, were determined by in situ EPR (electron paramagnetic resonance) and in situ UV-visible spectroscopy. Further kinetic studies revealed that the oxidation of benzyl alcohol follows the Michaelis-Menten kinetics, with K-m = 0.133 mol/L.A mathematic kinetic model was proposed, and the kinetic model fitted the experimental data well. The mathematical model can predict the reaction process at a wide range of benzyl alcohol concentrations, which is beneficial for the process optimization and reactor design. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

In a membrane microchannel reactor, the selective aerobic oxidation of benzyl alcohol to benzaldehyde catalyzed by cobalt porphyrin achieved high efficiency, with a conversion and benzaldehyde selectivity of 82% and 98% in 6.5 min. Kinetic studies revealed that the oxidation follows Michaelis-Menten kinetics, with a proposed mathematic kinetic model that fits well with experimental data and can predict reaction processes at various benzyl alcohol concentrations, aiding in process optimization and reactor design.