乙醇氧化羰基化法合成碳酸二乙酯的热力学计算与分析

THERMODYNAMIC ANALYSIS OF THE SYNTHESIS OF DIETHYL CARBONATE BY OXIDATION CARBONYLATION OF ETHANOL

利用Benson基团贡献法计算了碳酸二乙酯的热力学数据标准生成焓ΔfHθm 和热容Cp。计算了乙醇氧化羰基化法合成碳酸二乙酯反应的自由能ΔrG、平衡常数Kp 以及CO2 、CO和乙醇的平衡转化率。反应ΔrGθm 在 0 .1MPa、0～ 80 0K范围内均为负值 ,反应的平衡常数Kp、CO的平衡转化率较大 ,通过对实际生产中存在的主副反应讨论知 :从热力学角度分析温度上升有利于碳酸二乙酯的生成 ,反之温度降低有利于草酸二乙酯的生成。

The standard heat of formation and heat capacity of Diethyl Carbonate (DEC) are calculated by the method of Benson group contribution, the free energy change of the reaction ΔrG, equilibrium constant K p and equilibrium conversion of CO 2, CO and ethanol are evaluated according to the chemical thermodynamics principle. The results show the synthesis of DEC with C 2H 5OH and CO as feedstocks are favorable and there is higher equilibrium transformation rate. At the same time the bypass reaction in actual production is discussed, the results show that it is helpful for generating DEC when temperature rising and it is helpful for generating Diethyl Oxalate(DEO) when temperature dropping.