Concentrations of reactant, intermediate, product were measured by HPLC during nitrolysis of DADN (1,5-diacetyl-3, 7-dinitro-1, 3, 5, 7-tetraazacyclooctane) by N2O5/HNO3 at temperatures of 303, 313, 323, and 333 K. Based on the mechanism of the nitrolysis reaction (first-order consecutive reaction), the kinetic parameters were calculated from these data obtained. The activation energies were 2. 3996 ×104 J · mor-1 for the first step (DADN to SEX (1-acetyl-3, 5, 7-trinitro-1, 3, 5, 7-tetrazacyclooctane)) and 1. 6598×104 J · mol-1 for the second step (SEX to HMX (high melt point explosive)), and the pre-exponential factors were 2. 2000 ×104 h-1 and 6. 5178×102 h-1 , respectively. The reaction rate constant is larger for the fist step than for the second one. In order to check the intermediate in nitrolysis reaction of DADN, an experiment was carried out to separate and identify the intermediate (also by-product). The results indicate that this intermediate is SEX.%采用高效液相色谱跟踪检测了不同温度条件下N2O5/HNO3体系硝解DADN时反应底物、中间体和产物浓度随时间的变化情况.通过对303、313、323、333 K温度下实验数据的分析,计算得到各步的反应速率常数,并最终求得DADN到SEX和SEX到HMX两步的反应活化能分别为2.3996×104 J·mol-1和1.6598×104J·mol-1,指前因子分别为2.2000×104 h-1和6.5178×102 h-1.同时,通过柱分离得到的中间产物经结构鉴定为SEX,对其硝基机理进行了分析,实验证明DADN的硝解反应分两步进行,是一级连串反应过程,控制步骤是SEX到HMX.
展开▼
