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将La添加到Cu/ZnO-Al_2O_3上,用共沉淀法和硼氢化钾还原法制备了一系列不同La含量的催化剂,并考察了其对CO_2和CH_3OH直接合成碳酸二甲酯反应的催化性能的影响。运用X射线衍射(XRD)、低温氮气吸附法(BET)、H_2程序升温还原(H_2-TPR)、程序升温脱附法(TPD)对La改性后的催化剂进行了表征。并考察了改性后催化剂在优化条件下的稳定性。经过实验研究,确定了CO_2和CH_3OH直接合成碳酸二甲酯的最佳反应条件:催化剂中La的含量为3%时,催化剂表现出了最好的活性,甲醇的转化率可达8.22%,DMC选择性为83.26%。
La was added to Cu / ZnO-Al_2O_3, and a series of catalysts with different La content were prepared by coprecipitation method and potassium borohydride reduction method. The effects of La on the catalytic performance of direct synthesis of dimethyl carbonate from CO_2 and CH_3OH influences. The La modified catalysts were characterized by X-ray diffraction (XRD), low temperature nitrogen adsorption (BET), H 2 temperature-programmed reduction (H 2 -TPR) and temperature programmed desorption (TPD) The stability of the modified catalyst under optimized conditions was also investigated. Through experimental study, the optimal reaction conditions for the direct synthesis of dimethyl carbonate from CO_2 and CH_3OH were determined. When the content of La in the catalyst was 3%, the catalyst showed the best activity, the conversion rate of methanol was up to 8.22%, DMC Selectivity was 83.26%.