一元氯化镁化合物热分解的热力学研究

Thermodynamic Study of Thermal Decomposition of Magnesium Chloride Compounds

本文利用Gaussian 03程序,采用量子化学理论,在RHF/6-31G（d）水平上,对一元氯化镁化合物热分解反应机理进行了研究。在对现有4种水氯镁石脱水技术的反应物和产物几何构型进行能量梯度法全优化的同时,计算了不同温度下4种方法的主副反应路径的标准热力学参数（298.15~1000 K）。热力学计算结果表明：所有反应均为吸热反应,当压力为1.01×105 Pa、温度低于1000 K时,所有反应都不能自发进行;从热力学的角度分析,热分解更有利于以苯胺为助剂的复盐法的发生。

The thermal decomposition mechanism of magnesium chloride compound was studied by quantum chemical theory,with Gaussian 03 package at RHF/6-31G（d） level.To four kinds of bischofite dehydration technology,the equilibrium geometries of reactants and products were calculated,and the standard thermodynamic parameters of main and side reaction paths in different temperature ranges were optimized respectively.The thermodynamic calculation results show that all above reactions are endothermic process and can take place non-spontaneously when reaction temperature is less than 1 000 K and pressure is 1.01 ×10 5 Pa.Analyzed from thermodynamic theory,the thermal decomposition of magnesium chloride compounds favors to produce to the reaction of complex thermal decomposition method by aniline.