Heterogeneous peroxidation of benzoyl chloride with H ₂ O ₂ in packed‐bed microreactors: Reaction regime and kinetics

Benzoyl peroxide (BPO), a widely used diacyl peroxide, is typically synthesized via heterogeneous peroxidation of benzoyl chloride (BC) and H 2 O 2 in batch reactors—a process that suffers from low space–time yields and safety concerns. This study developed a safe and efficient continuous‐flow synthesis using packed‐bed microreactors. Importantly, a kinetic model coupling intrinsic reaction kinetics and mass transfer was established and validated across different packing sizes, providing mechanistic insight into the heterogeneous liquid–liquid process. The main reaction followed a slow regime governed by both kinetics and mass transfer, whereas the hydrolysis side reaction occurred in a very slow regime with negligible mass transfer resistance. Consequently, packed‐bed microreactors enhanced mass transfer and improved BPO selectivity. Under optimal conditions (NaOH/BC = 1.0, H 2 O 2 /BC = 0.6, 50°C), a 94.4% BPO yield was achieved within 120 s. The space–time yield was over 51 times that of batch reactors. This study offers insights for intensifying and scaling up diacyl peroxide syntheses.