一硝基甲苯硝化过程的热危险性

Thermal Hazard in the Process of Mononitrotoluene Nitration

为获得一硝基甲苯(MNT)硝化生成二硝基甲苯反应过程中的热危险性信息,用差示扫描量热法(DSC)测试了反应体系及所涉物质的热分解行为。通过反应量热器(RC1e)对反应放热过程进行了研究。结果表明,混酸最易分解,在反应后的混合体系中热分解开始温度为113.3℃。在半间歇反应条件下,若在冷却失效时立即停止MNT加料,则体系的最高温度不超过100℃;否则反应放出的总热量可使体系绝热温升140℃以上,引起二次分解反应。

To get thermal hazard information in the process of forming dinitrotoluene from mononitrotoluene （MNT）, DSC was used to test the thermal decomposition behaviors of these substance referred, and reaction calorimeter （RC1e） was used to study the heat generation in the reaction process. The results show that the decompositon of mixed acid easily took place and the onset temperature of decomposition reaction for mixed system after the reaction is 113.3 ℃. And the maximal temperature attainable by runaway of the desired synthetic reaction （MTSR） is lower than 100℃ if MNT dosing could stop as soon as cooling failure, or else, the adiabatic temperature arise can be higher than 140 ℃, and lead a secondary decomposition reaction.