Thermal reactive hazards of 1,1-bis(tert-butylperoxy)cyclohexane with nitric acid contaminants by DSC

With two active O-O peroxide groups, 1,1-bis(tert-butylperoxy)cyclohexane (BTBPC) has a certain degree of thermal instability. It is usually used as an initiator in chemical processes, and therefore reckless operation may result in serious thermal accidents. This study focused on the runaway reactions of BTBPC alone and mixed with various concentrations of nitric acid (1, 2, 4, and 8 N). The essential thermokinetic parameters, such as exothermic onset temperature (T (o)), activation energy (E (a)), frequency factor (A), time to maximum rate under adiabatic condition (TMRad) and time to conversion limit (TCL), were evaluated by differential scanning calorimetry at the heating rate of 4 A degrees C min(-1), and a kinetics-based curve fitting method was used to assess the thermokinetic parameters. All the results indicated that BTBPC mixed with one more than 4 N nitric acid dramatically increased the degree of thermal hazard in the exothermic peak and became more dangerous. However, it was relatively safe for BTBPC mixed with less than 1 N nitric acid under 34.5 A degrees C.