碳酸二甲酯与苯酚酯交换反应动力学研究

The reaction kinetics of transesterification from dimethyl carbonate and phenol

采用自制钛催化剂,研究了碳酸二甲酯与苯酚反应生成甲基苯基碳酸酯的反应动力学,考察了反应温度对苯酚转化率的影响,确定了碳酸二甲酯与苯酚反应的热力学和动力学数据,建立了动力学模型并进行了统计学检验。实验结果表明,在自制钛催化剂用量为0.28%(w)、438~468 K条件下,碳酸二甲酯与苯酚生成甲基苯基碳酸酯反应的二级动力学方程对实验数据拟合良好,正反应速率常数的指数前因子为2.70×10~3 L/(mol·min),逆反应速率常数的指数前因子为6.08×10~2 L/(mol·min),反应热为35.95 k J/mol,反应熵为12.72 J/(mol·K)。

The reaction kinetics of methyl phenyl carbonate from dimethyl carbonate(DMC)and phenol which catalyzed by self-made titanium catalyst was investigated.The influence of reaction temperature on the conversion of phenol was investigated.The data of reaction thermodynamics and kinetics of DMC and phenol were determined.A second order reaction kinetics of model was established and a statistical test was carried out.It was found that,catalyzed by self-made titanium catalyst(0.28%(w)),the reaction model was well fitted to the experimental data,the pre-exponential factor of positive reaction rate constant of methyl phenyl carbonate from DMC and phenol is 2.70×103 L/(mol·min),and the pre-exponential factor of negative reaction rate constant is 6.08×102 L/(mol·min)under the temperature range of 438-468 K.The heat and entropy of the reaction are 35.95 kJ/mol and 12.72 J/(mol·K),respectively.