酯交换法合成碳酸二苯酯的技术分析

从化学反应热力学可行性、工艺流程、原子经济性等方面对合成碳酸二苯酯(DPC)的3种酯交换法(碳酸二甲酯(DMC)与苯酚酯交换法、草酸二甲酯(DMO)与苯酚酯交换法、DMC与乙酸苯酯(PA)酯交换法)进行了分析。DMC与苯酚酯交换法、DMO与苯酚酯交换法的反应平衡常数较小,需要将甲醇移出以利于反应向产物方向移动,反应时间长,过程设计复杂,工程投资较大;DMC与PA酯交换法涉及的主要反应的反应平衡常数较大,反应比较容易进行,具有反应时间短、反应过程设计简单等特点,且副产物可以通过转化再利用,实现"100%原子利用率",极具工业化前景。提出了加大研究开发和投资力度,以加快DMC与PA酯交换法合成DPC工业化进程的建议。

Technological Analysis of Synthesis of Diphenyl Carbonate by Transesterification

Syntheses of diphenyl carbonate(DPC) through three transesterifications,namely transesterification of dimethyl carbonate(DMC) with phenol,transesterification of dimethyl oxalate(DMO) with phenol and transesterification of DMC with phenyl acetate(PA),were analyzed and compared in chemical thermodynamics,technological processes and atom economy. Equilibrium constants for transesterifications of DMC with phenol and DMO with phenol are smaller,so removal of methanol from the systems is necessary to promote the synthesis of DPC. Applications of the above two transesterifications are restricted due to long reaction time,complicated engineering design and high investment. Transesterification of DMC with PA is easy in thermodynamics,simple and convenient in operation,and short in total reaction time,which reduced the operation cost. And the by-products can be reused. It is believed that the transesterification of DMC with PA is a promising industrial route for DPC production.