煤制甲醇合成气中有机氯化物生成反应的热力学分析

Thermodynamic analysis of organic chloride generation reactions in coal-to-methanol syngas

为分析煤制甲醇合成气中有机氯化物的来源及生成机理,利用原子系数矩阵法确定了该生成反应体系的一组独立反应,根据Rozicka-Domalski基团贡献法、Benson基团贡献法及手册查询计算出各组分的标准生成热、标准熵及恒压比热容后,利用热力学方法计算了不同条件下该反应体系中各独立反应的吉布斯自由能变,据此判断在指定条件下各独立反应发生的可能性。结果表明,常压、温度低于550 K时氯乙烷、氯丙烷及氯丁烷可自发生成,增大压力有助于增加该类有机氯化物的自发生成的可能性,分析结果可为煤制甲醇合成气中有机氯化物的生成及后续脱除技术开发提供指导。

In order to analyze the source and formation mechanism of organic chlorides in coal-to-methanol syngas,a set of independent reactions of the formation reaction system was determined by atomic coefficient matrix method.After calculating the standard heat of generation,standard entropy and constant pressure specific heat capacity of each component according to the Benson group contribution method and manual query,the Gibbs free energy change of each independent reaction in the reacting system under different condition was calculated by thermodynamic methods,and the possibility of each independent reaction under the specified conditions was judged.It can be seen from the calculation results that chloroethane,chloropropane and chlorobutane can occur spontaneously when the normal pressure and temperature are lower than 550 K,and increasing the pressure helps to increase the possibility of spontaneous formation of such organochlorides.The analysis results can insight to the generation of organic chlorides in coal to methanol syngas and the subsequent development of the technology for the removal of organochloride.