【摘要】 采用共沉淀法制备了Cu/MgO催化剂并经La和K修饰,研究了含CO2的CO原料气加氢低温甲醇合成性能.采用XRD,CO-TPD和CO2-TPD等手段对催化剂的物相结构和表面吸附行为进行了表征.结果表明,La的添加促进了Cu组分的分散,增强了CO和CO2低温吸附能力,CO2加氢活性提高;进一步经K修饰后,催化剂表面碱性明显增强,CO和CO2高温吸附能力增强,促使CO和CO2同步转化,催化活性和甲醇收率明显提高,但副产物甲酸乙酯含量增加;当n(Cu)∶n(K)为10∶1时,总碳转化率达29.7%,甲醇收率较高,且催化剂具有较好的稳定性.更多还原

【Abstract】 La and K promoted Cu/MgO catalysts were prepared by coprecipitation method.The catalytic performance of the catalysts on low-temperature methanol synthesis from CO2-containing syngas was investigated.The catalysts were characterized by means of XRD and TPD measurements.The results indicated that La2O3 addition improved Cu dispersion,which enhanced the low temperature CO and CO2 adsorption ability and promoted the conversion of CO2.With the further addition of K2O,the improved surface basicity caused an increase in CO and CO2 high temperature adsorption.The simultaneous conversion of CO and CO2 was achieved,and the activities of the catalyst and methanol yields were enhanced,while the selectivity of ethyl formate was increased.The catalyst with Cu/K molar ratio of 10∶1 showed high activity and stability,and the total carbon conversion of 29.7% was obtained with high methanol yield.更多还原