二氧化碳加氢直接合成二甲醚反应体系的热力学

为了有效利用二氧化碳资源,对二氧化碳加氢直接合成二甲醚进行了研究．在对二氧化碳加氢直接合成二甲醚反应体系进行的热力学研究中,用逸度系数校正了压力的效应,模拟计算分析了反应体系达到热力学平衡时各组分的组成及其与温度、压力和H_2与CO_2的比之间的关系．经计算得出,在533 K、3 MPa和H_2与CO_2的体积比为3的反应条件下,当体系达到热力学平衡状态时,CO_2的平衡转化率为26．49％,二甲醚的平衡收率为14．9％．研究结果表明,为获得较高的目标产物二甲醚的收率,可以通过调整反应条件控制CO的生成量,充分发挥催化剂中甲醇脱水组分的作用,及时脱除反应中生成的水,使平衡向有利于二甲醚的方向转移．

Thermodynamics of Balanceable Reaction System for Hydrogenation of Carbon Dioxide to Dimethyl Ether

To use the resource of carbon dioxide effectively, synthesis of dimethyl ether ( DME) from carbon dioxide hydrogenation was studied. In the investigation of thermodynamics for hydrogenation of carbon dioxide to DME, the effect of pressure on parameters was corrected with fugacity coefficient. Through simulated calculation , the equilibrium composition and the relations with reaction conditions, such as temperature, pressure and the ratio of H2 to CO2 ,in the reaction system were analyzed. Under the conditions of 533 K,3 MPa and that the ratio of H2 to CO2 is 3, CO2 equilibrium conversion is 26.49%, and DME equilibrium yield is 14. 9%. The results show that, in order to achieve higher yield of the object product, DME, it is necessary to control reaction conditions to decrease formation of CO, to fully utilize the effect of dehydration component of methano1, and to promptly remove the water produced during the reaction process.