Thermal Hazard Analysis of Methyl Ethyl Ketone Peroxide

In the past forty years in Japan and Taiwan, many thermal explosions have been caused by methyl ethyl ketone peroxide (MEKPO) under the influence of external fire and others. Thermograms of commercialized MEKPO dimers were first screened by Differential Scanning Calorimetry (DSC) to determine the heat of decomposition and exothermic onset temperature. Thermal runaway phenomena were then thoroughly investigated by Vent Sizing Package2 (VSP2). Data of thermokinetics and hazard behaviors were used for hazard analysis of MEKPO thermal explosions. The onset temperatures of MEKPO monomer, which was prepared by the reaction of methyl ethyl ketone (MEK) and H2O2, were determined to be at about 40 C, showing extremely dangerous while operating in hot ambient conditions, which is the first finding in literature. The novel finding shows that two peaks on the thermograms that indicate the MEKPO thermal runaway is a complicated reaction mechanism, requiring further study for detailed thermal hazard investigation in the future. Instead of normal one reaction peak from the adiabatic calorimeter, two exothermic peaks on the DSC thermograms is another novel finding among literatures. It was found that the reaction order of 1 peak of MEKPO dimer decomposition by isothermal analysis was 1. The Arrhenius parameters were calculated to be Ea (kcal mol) = 27.0 and lnA (s) = 29, with reproducible confirmation. The reaction order of the 2 peak of MEKPO dimer decomposition was 0.3 by DSC, showing the Arrhenius parameters of Ea (kcal mol ) = 27.5 and lnA (s) = 23. By VSP2 the Arrhenius parameters were determined as lnA (s) = 20.7, Ea (kcal mol ) = 20.3, and n = 1, respectively. Preventative measures can be established by these basic parameters so that the pro-active disaster prevention program can be practically achieved.