金属镁粉氮化反应的理论与实验研究  

Theory and experimental study of nitridation reaction of Mg

作　　者：过乐驹 陈明华 陈永康 张欢迪 Guo Leju;Chen Minghua;Chen Yongkang;Zhang Huandi(Army Unit 32681,PLA,Tieling 112000;Army Unit 32181,PLA,Shijiazhuang 050000;Jilin University,Changchun 130000)

机构地区：[1]32681部队,铁岭112000 [2]32181部队,石家庄050000 [3]吉林大学,长春130000

出　　处：《化工新型材料》2020年第4期172-175,180,共5页New Chemical Materials

基　　金：军内预研项目(涉密)。

摘　　要：为研究镁粉在氮气中的反应机理和过程,采用从头算二阶多体微扰理论MP2/6-311+G(d)方法优化反应物、中间体和产物的几何构型,分析其电子结构,通过计算得到反应势能为435.18kJ/mol,氮化反应中镁和氮气形成中间体MgN2的过程为反应控制步骤,并对反应机理进行了分析。利用热重法对镁与氮气的反应过程进行了测试,根据Flynn-Wall-Ozawa积分法、Starink微分法和一般积分法计算了反应的动力学参数,得到反应活化能、指前因子和动力学方程。研究表明氮化反应分为3个阶段,利用Flynn-Wall-Ozawa积分法、Starink微分法和一般积分法得到的氮化反应平均活化能分别为410.56kJ/mol、412.86kJ/mol和409.21kJ/mol,平均指前因子为4.52×10^15s^-1,热分解动力学方程为dα/dt=1.64×10^13[2-ln(1-α)]e^-59.18。In order to study the reaction mechanism and process of Mg powder in N2,the optimized geometries,dipole moment and frequencies of all the stationary points were calculated at MP2/6-311+G(d)level.The potential energy surface was 435.18kJ/mol.The reaction producing MgN2was the controlling step.The mechanism was analyzed.Thermal analysis of the reaction between Mg and N2 was carried out by thermogravimetry.The kinetic parameters of thermal decomposition were calculated by Flynn-Wall-Ozawa(FWO)method,Starink method and general integral method.The activation energy,pre-exponential factor and kinetic equation of Mg were calculated by three thermal analysis kinetics equations.It shown that the nitridation reaction included three steps.The activation energy E obtained by FWO method,Starink method and general integration method were 410.56,412.86and 409.21kJ/mol respectively.The pre-exponential factor A was 4.52×10^15s^-1,and the kinetic equation of thermal decomposition was d α/dt=1.64×10^13[2-ln(1-α)]e^-59.18.

关 键 词：氮化镁 镁粉 量子化学 热动力学 

分 类 号：O643.12[理学—物理化学]