通过沉淀凝胶法制备了不同铈质量分数的铜铈硅催化剂.采用氢气程序升温还原、氢气程序升温脱附、X射线衍射等手段对催化剂进行表征.在连续流动固定床反应器上考察了铜铈硅催化剂上甘油氢解制备1,2-丙二醇的性能.结果表明:铈的引入使催化剂的还原峰从258℃提前到250℃,催化剂的氢脱附峰温度从129℃降低到100℃左右,并且提高了催化剂的稳定性.以乙醇溶剂代替水,抑制了活性中心Cu°晶粒的长大,获得了95.9％的甘油转化率和96.9％的1,2-丙二醇选择性,催化剂在200 h内没有出现失活现象.%A series of ceria-promoted Cu/SiO2 catalysts were prepared by precipitation-gel method. The physic-chemical properties were characterized by H2 temperature-programmed reduction (H2-TPR), H2 temperature-programmed desorption (H2-TPD) and X-ray diffraction (XRD) methods. Their catalytic performance for glycerol hydrogenolysis to 1,2-propanediol were studied in a fixed-bed continuous flow reactor. The results indicated that ceria improved the stability of Cu/SiO2 catalysts by altering the reduction peak from 258 ℃ to 250 ℃ and reducing the H2 desorption peak temperature from 129 ℃ to around 100 ℃. Furthermore, replacing water with ethanol can restrain Cu0 from sintering and promote the performance of Cu/SiO2 catalyst, which could keep its activity in 200 h. The conversion of glycerol and the selectivity of 1,2-propanediol could be up to 95. 9% and 96. 9% respectively.
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