CO_2/H_2和(CO/CO_2)+H_2低压合成甲醇催化过程的本质

Comparison Studies on the Catalysis Process of Methanol Synthesis from CO_2+H_2 and (CO/CO_2) +H_2

通过在Cu／ZnO／Al2O3催化剂上CO2＋H2、CO＋H2和（CO／CO2）＋H2催化反应动力学研究，对合成甲醇动力学和反应机理进行了细致分析，提出合成甲醇的反应机理，解释了在（CO／CO2）＋H2合成甲醇过程中少量CO2的作用及合成甲醇的直接碳源．

The catalytic processes of methanol synthesis from CO2+H2, CO+H2 and (CO/CO2) +H2 have been studied. The results indicate that methanol is primarily formed fromCO2 hydrogenation for both CO2+H2 and (CO/CO2) +H2. Due to the limitation of thermaldynamics, the yield of methanol is low for CO2 hydrogenation. In the process of (CO/CO2)+H2, methanol selectivity and formation rate are promoted greatly due to the recycle processof methanol synthesis from CO2+H2 and reverse water-gas shift reaction. As a result, thelimitation of thermodynamic equilibrium of methanol synthesis from CO2, hydrogenation ismoved to the favorable side of methanol synthesis. A novel reaction mechanism is proposed.