Thermal instability and kinetic analysis on m-chloroperbenzoic acid

Abstract

m-Chloroperbenzoic acid (MCPBA) has been widely applied as an oxidant agent for various oxidations in organic chemistry. The understanding of thermal instability and kinetics is a prerequisite for safer storage and transportation. This study investigated the thermal decomposition characteristics of MCPBA under dynamic and adiabatic conditions by performing TG, DSC and ARC tests, respectively. Kinetic parameters were computed using Starink method and compensation effect. Thermal safety parameters, including critical temperature of thermal explosion (Tb) and time to maximum rate under adiabatic conditions (TMRad), were determined to assess the thermal hazard of MCPBA. The experimental results showed two major thermal decomposition processes and a coupling phenomenon of heat absorption and generation. The mean value of Ea was determined as 57.630 kJ mol−1, and the best model to describe the overall reaction mechanism was three-dimensional diffusion model with integral form \(G\left( \alpha \right) = \left[ {1 - \left( {1 - \alpha } \right)^{1/3} } \right]^{2}\) for 0.05 < α < 0.80. The TMRad was 24 h with an apparent onset temperature of 345.82 K. This study provided a guidance to determine the safety measures in MCPBA storage and transportation.