强酸性离子交换树脂催化下硼酸三甲酯合成反应的动力学研究

Kinetics of synthesis of trimethyl borate on laden lithium chloride acid ion-exchange resin

以自制的负载氯化锂强酸性离子交换树脂为催化剂,采用间歇法研究了硼酸和甲醇酯化可逆反应的动力学。对可逆反应动力学方程进行线性化处理,确定了积分法拟合可逆反应动力学参数的方法,并以幂函数形式表达了指前因子与催化剂浓度的关系。测定了不同反应温度和催化剂用量下硼酸三甲酯得率随时间的变化,对动力学数据采用线性拟合,得到硼酸三甲酯非均相催化合成反应动力学方程式为:rA=499.4 C0.38cat exp(-31920/RT)CACB-397.7C0.08 cat exp(-29780/RT)CRCS。

The kinetics of the reversible reaction between boronic acid and methanol was investigated by using the selfmade strong acid cation exchange resin loaded with lithium chloride as the catalyst. A method was established for fitting parameters of reversible reaction kinetic model derived from the integration method, and the relationship between pre-exponential constants and concentration of catalyst was expressed by power function. According to the variation of trimethyl borate yield with time, temperature and the amount of catalyst, the kinetic model was fitted by linear method. The equation of synthesis kinetics of trimethyl borate by inhomogeneous catalysis was showed as ：rA=499.4C^0.38 cat exp（-31920/RT）CACB-397.7C^0.08 cat exp（-29780/RT）CRCS.