Thermal Hazard Analysis and Decomposition Mechanism of Energetic Nitration of 4-Methoxy-2-nitroacetanilide

The thermal hazard parameters of dangerous chemicals should be determined through scientific methods to prevent dangerous chemical accidents and realize sustainable development in the chemical industry. In this study, the thermal hazard of the nitrification product 4-methoxy-2-nitroacetanilide (AMN) was assessed through various calorimetric methods and thermal analysis techniques. The autocatalytic decomposition characteristics of AMN were determined and validated through dynamic and isothermal differential scanning calorimetry and accelerating rate calorimetry experiments. The variation trend of activation energy (E_a) with conversion (α) and the results of thermogravimetric analysis indicated that the thermal decomposition of AMN involved a single reaction process. The activation energy for the thermal decomposition reaction was calculated to be 34.32-37.99 kJ/mol through the model-free method, and the possible reaction mechanism was determined using the Málek method. Finally, the thermal safety of the energetic materials was analyzed, and the self-accelerating decomposition temperature, hot spot fire temperature, and thermal explosion critical temperature were calculated.