Process hazard and decomposition mechanism of benzoyl peroxide in the presence of incompatible substances

Abstract

Benzoyl peroxide (BPO) is a hazardous chemical, which is incompatible with many substances. Due to its high thermal sensitivity, it reacts violently with organic chemicals and can cause serious explosions when heated. Toluene and sodium hydroxide (NaOH) are incompatible substances frequently encountered in the production and utilization of BPO. Therefore, it is necessary to investigate the thermal decomposition behavior of BPO and its reaction mechanism under the effect of impurities. In this paper, thermal decomposition behavior of BPO, the mixture of BPO and toluene, and the mixture of BPO and NaOH were studied using differential scanning calorimetry and adiabatic calorimetry under different conditions. The decomposition kinetic models were obtained to simulate thermal runaway behavior in actual package. Chromatography-Mass Spectrometry experiments were performed to examine the composition of thermal decomposition products in different systems. The results show that NaOH improves the thermal stability of BPO and toluene makes it easier for BPO decomposition. Both NaOH and toluene change the decomposition path of BPO. The consumption of benzoic acid radicals is accelerated by NaOH. Toluene makes the decomposition of BPO follow an n-order reaction by consuming phenyl radicals generated by the decomposition of BPO. This study is important for understanding thermal hazards of BPO at the reaction mechanism level and ensuring process safety in industrial processes.