Cu/SiO_2的表征及其在乙酸乙酯加氢合成乙醇中的催化性能

采用尿素均匀沉淀法制备了Cu/SiO2催化剂,用H2-TPR、XRD和N2吸附-脱附等技术对其进行了表征;将Cu/SiO2催化剂用于催化乙酸乙酯加氢制备乙醇的反应,考察了反应温度、反应压力、反应物配比和液态空速对乙酸乙酯加氢反应活性和选择性的影响。表征结果显示,Cu/SiO2催化剂具有较大的比表面积和较低的起始还原温度。实验结果表明,适宜的反应条件为:反应温度220℃、反应压力3.0MPa、氢气与乙酸乙酯的摩尔比60、液态空速1.0h-1,在此条件下,乙酸乙酯转化率可达96.2%,乙醇选择性为97.8%。

Characterization of Cu/SiO2 Catalyst and Its Performance in Hydrogenation of Ethyl Acetate to Ethanol

A Cu/SiO2 catalyst was prepared by a homogeneous precipitation method with urea as the precipitant,characterized by means of H2-TPR,XRD and BET,and used in the hydrogenation of ethyl acetate to ethanol.The effects of temperature,pressure,mole ratio of H2 to ethyl acetate and LHSV on the activity and selectivity of the catalyst were investigated.The results show that the catalyst has high specific surface area and low initial reduction temperature.The catalyst performance in the hydrogenation reaction was evaluated.Under the optimal reaction conditions of temperature 220 ℃,pressure 3.0 MPa,n(H2):n(ethyl acetate) 60 and LHSV 1.0 h-1,the conversion of ethyl acetate and the selectivity to ethanol reached 96.2% and 97.8%,respectively.