Evaluation of the Thermal Hazard of the Oxidation Reaction in the Synthesis of 3,4-Bis(4-nitrofurazan-3-yl)furoxan

Safety evaluation of chemical reactions is very significant before industrial applications are conducted. A lot of thermal hazards are generated in the synthesis of 3,4-bis(4-nitrofurazan-3-yl)furoxan (DNTF) because of the strong exothermicity of the oxidation reaction, unstable hydrogen peroxide, and interactions between the materials. In this article, systematic parameters regarding the safe synthesis of DNTF were studied, including the preparation stage of reaction solution and the oxidation reaction step. A Calvet microcalorimeter and an RC1mx reaction calorimeter were employed for process safety research. Differential scanning calorimetry and adiabatic accelerating rate calorimetry were used to investigate the thermal stabilities of the materials and their thermal hazards. After screening of the thermal stabilities of the materials in the two stages, hazardous materials were identified, and their thermal safety parameters were obtained. Finally, two evaluation methods were applied to evaluate the hazard levels of the preparation process and the oxidation reaction process in the synthesis of DNTF on the basis of thermal safety parameters. This study provides critical safety technical guidance for the DNTF synthesis process and safety design.