缩合法合成甲基苯基二氯硅烷反应热力学研究  

Thermodynamic Research on Synthesis of Dichloromethylphenylsilane by Condensation Method

作　　者：刘彤[1] 黄云龙[1] 王光润[1] 王金福[1] 

机构地区：[1]清华大学化学工程系,绿色反应工程与工艺北京市重点实验室,北京100084

出　　处：《化学反应工程与工艺》2011年第5期454-459,共6页Chemical Reaction Engineering and Technology

摘　　要：本工作研究了氯苯和甲基二氯硅烷气相缩合生成甲基苯基二氯硅烷反应体系,指出在温度低于600℃时,反应体系可由一个主反应和两个副反应组成的反应网络描述,并给出了此三个反应的平衡常数和反应热。利用吉布斯自由能最小化原理计算了热力学平衡组成和产品的平衡收率。计算表明由于副反应的平衡移动,温度升高有利于提高甲基苯基二氯硅烷的平衡收率。综合考虑缩合反应、副反应以及原料在高温下的裂解结炭反应,通过平衡收率与实验收率的比较,明确了随着温度的升高,反应经历了由动力学限制过渡到热力学限制,再过渡到裂解反应占主导的过程。确定了合成过程的最优反应温度为600℃。计算出此温度下反应热为-102 kJ/mol。产品平衡收率为36%。由于主反应的平衡常数大于107,所以原料的平衡转化率大于99%,而且配料比R=C6H5Cl:CH3SiHCl2<1时,平衡收率随R的增大而增大;当R>1时,平衡收率不再随R变化。Synthesis of dichloromethylphenylsilane by gas phase condensation reaction,in which chlorobenzene reacts with methyldichlorosilane,was investigated in this paper.Below 600 ℃,the reaction system can be characterized by one main reaction and two side reactions,equilibrium constants and reaction heat of which were given.The equilibrium composition and yield of desired product were calculated by minimizing global Gibbs free energy.Because of equilibrium shifting of side reactions,an increase in temperature favors the yield of dichloromethylphenylsilane.It＇s clear by comparing experimental and calculated results that reaction system undergoes a transition from dynamic to thermodynamic limit,and pyrolysis is dominant at higher temperature.Optimum temperature is 600 ℃,at which the heat of reaction system and equilibrium yield of desired product are-102 kJ/mol and 36%.Equilibrium conversion of reactant is greater than 99%,because the equilibrium constant is greater than 107.When feed ratio R（C6H5Cl：CH3SiHCl2）1,equilibrium yield increases with R.But the yield stay constant when R1.

关 键 词：缩合法 甲基苯基二氯硅烷 热力学 

分 类 号：TQ264.1[化学工程—有机化工] O642.1[理学—物理化学]