Runaway reaction and thermal hazards simulation of 4-amino-1,2,4-triazole picrate by HP-DSC and ARC

4-Amino-1,2,4-triazole picrate (4-ATPA) is a type of ionic liquids, as well as an explosive with sound thermal stability and low mechanical sensitivity. However, under upset conditions such as high temperature and pressure, an unpredictable explosion would occur and result in huge casualties and property losses. The purpose of this research was to evaluate the thermal hazard and runaway reaction of 4-ATPA through high-pressure differential scanning calorimetry and accelerating rate calorimeter. The kinetic parameters of decomposition reaction under non-isothermal and different pressure conditions were calculated based on the experiment results. Experimental results showed that the β and test pressure had no effect on the amount of heat release. Adiabatic experiments indicated that 4-ATPA had a high onset temperature at 196.8 °C. The maximum self-heating rate (3567.9 °C min−1) and pressure rise rate (202.0 bar min−1) revealed the vulnerability of 4-ATPA to suffer a disastrous explosion. Moreover, the apparent activation energy and pre-exponential factor were evaluated as 110.2 kJ mol−1 and 1.8 × 10−15 s−1 by ASTM E698 method. The correctness of the thermodynamic calculation formula under adiabatic conditions is verified by ARC tests. Finally, the thermal hazard risk of 4-ATPA was classified as unacceptable based on the risk classification criteria.