硝酸、硫酸对三硝基均苯三酚热分解特性的影响

三硝基均苯三酚（TNPG）在硝化过程中不可避免地会接触到酸根离子。为了探究硝酸、硫酸作用下TNPG的热分解特性，采用差示扫描量热仪（DSC）对合适酸含量的样品在不同升温速率条件下进行测试，并进行动力学分析与预测。DSC测试结果表明，TNPG的起始分解温度为198.35 ℃，硝酸和硫酸都能促进其热分解过程，随着酸含量的增加，起始分解温度降低。无模型法计算得到TNPG的活化能变化范围为97~103 kJ/mol，而酸作用下的TNPG较不稳定，活化能为20~94 kJ/mol（硝酸作用）和135~224 kJ/mol(硫酸作用)。等温预测结果说明，各样品具有自催化分解特性；绝热预测结果表明，每个样品的T_D24分别为137.6 ℃（TNPG）、111.3 ℃（硝酸作用）和140.4 ℃（硫酸作用）。若在合成过程中发生热失控，采取控制措施的时间余量较大；需要将物质在阴凉、干燥、无酸根离子的环境中储存，避免外部火灾的发生。

Effect of Nitric Acid and Sulfuric Acid on Thermal Decomposition- Characteristics of Trinitrophloroglucinol

It is inevitable to touch acid ion like nitric and sulfuric during the synthesis of trinitrophloroglucinol (2,4,6-trinitro-1,3,5-benzoquinone, TNPG). In order to investigate the thermal stability of TNPG under the action of nitric acid and sulfuric acid, typical samples with a suitable amount of acid was screened by differential scanning calorimeter (DSC) under various heating rates, and their kinetic parameters were analyzed and calculated. Results show that initial decomposition temperature of TNPG is 198.35 ℃, and its thermal decomposition can be catalyzed by both acid nitric and sulfuric acid. With the increasing of acid amount, initial decomposition temperature could be lower. Activation energy of TNPG calculated with model free method is 97-103 kJ/mol. TNPG under the action of acid is relatively unstable showing activation energy ranges of 20-94 kJ/mol (with nitric acid) and 135-224 kJ/mol (with sulfuric acid), respectively. It can be known from the isothermal prediction results that the decomposition of each sample has autocatalytic decomposition characteristics. The T_D24?of each typical sample is predicted to be 137.6 ℃ (TNPG), 111.3 ℃ (with nitric acid) and 140.4 ℃ (with sulfuric acid). It is allowed a longer time to take control once the thermal runaway occurs during the synthesis process. It is necessary to store the material in a cool, dry, and acid-free environment, and be away from external fires.