溶剂萃取法回收TNT的安全性研究

为了更好地利用回收的废弃火炸药,以甲苯作为溶剂,利用溶剂萃取法从B炸药中回收TNT组分;采用液相色谱法测定回收TNT的纯度;采用差示扫描量热仪(DSC)和5 s爆发点实验对回收的TNT和对比样品进行了热安定性分析;测定了回收TNT的撞击感度和摩擦感度。结果表明,液相色谱法测得回收TNT纯度为94.19%,对比样品TNT纯度为96.66%;不同升温速率下,回收TNT熔化峰温较对比样品降低了0.9~1.4℃,分解峰温降低了5℃左右,活化能降低3.51 kJ/mol,表明回收TNT的热安定性有所降低;回收TNT的5 s延滞期爆发点为422.7℃,较纯TNT文献值低约53℃,比对比样品TNT高28.5℃;5 s爆发点变化与其所含杂质种类有关,回收TNT中的杂质对热感度的影响较小;回收TNT的撞击感度为8%,摩擦感度为4%,与对比样品相比均下降,表明回收TNT的安全性较好,能满足再利用的要求。

Study on the Safety of Reclaimed TNT by Solvent Extraction

In order to make better use of the abandoned explosives,TNT component was recycled from B explosive by solvent extraction with toluene as solvent.The purity of reclaimed TNT was determined by liquid chromatography.The thermal stabilities of reclaimed TNT and contrast samples were analyzed by differential scanning calorimeter(DSC)and 5 s explosion temperature experiment.Impact sensitivity and friction sensitivity of reclaimed TNT were measured.The results show that the purity of reclaimed TNT and contrast sample obtained by liquid chromatography are 94.19%and 96.66%,respectively.At different heating rates,the melting peak temperature of reclaimed TNT decreases by 0.9—1.4℃compared with the contrast sample,the decomposition peak temperature decreases by about 5℃,and the activation energy decreases by 3.51 kJ/mol,indicating that the thermal stability of reclaimed TNT decreases.The test result of 5 s explosion temperature is 422.7℃,about 53℃lower than the reference value of pure TNT,and 28.5℃higher than the contrast sample.The change of the 5 s explosion temperature is related to the type of impurities contained,and the impurities in reclaimed TNT have little effect on the thermal sensitivity.The impact sensitivity of reclaimed TNT is 8%and the friction sensitivity is 4%,both of which decrease compared with the contrast samples,indicating that the reclaimed TNT is safe and can meet the requirements of the reuse.