超声波辅助化学还原法制备Ru-B非晶态合金催化剂及用于麦芽糖催化加氢

Ultrasonic-Assisted Preparation of Ru-B Amorphous Alloy Catalyst Used in Hydrogenation of Maltose

采用超声波辅助化学还原法制备了Ru-B非晶态合金催化剂并用于麦芽糖加氢制备麦芽糖醇。采用X射线衍射、选区电子衍射、示差扫描量热、X射线光电子能谱、透射电子显微镜和H2吸附对Ru-B非晶态合金催化剂进行了表征。表征结果显示,与直接化学还原法制备的Ru-B非晶态合金催化剂相比,两者的结构、表面电子态和催化活性中心的本质均未发生明显变化,但前者比后者的颗粒更细,活性比表面积增大,导致催化活性明显提高。考察了超声波功率对Ru-B非晶态合金催化剂的结构及其催化活性的影响,确定了最佳超声波功率为60W。Ru-B非晶态合金催化剂的活性约为工业用Raney Ni催化剂的38倍左右,选择性为100%,且能重复使用6次以上,具有良好的工业化应用前景。

Ru-B amorphous alloy catalyst was prepared by ultrasonic-assisted chemical reduction and used in hydrogenation of maltose to maltitol. The prepared Ru-B shows similar amorphous alloy structure, surface electronic state and nature of active sites to Ru-B obtained by direct chemical reduction,but possesses smaller particle size than the latter, which results in its higher activity. Influences of ultrasonic power on structure of Ru-B amorphous alloy catalyst and catalytic activity were investigated by means of XRD, selected area electron diffraction （ SAED ）, DSC, XPS, TEM, H2 adsorption and hydrogenation. The optimal ultrasonic power is 60 W. Selectivity of prepared Ru-B amorphous alloy catalyst to maltitol can reach 100% and its activity nearly 38 times as that of Raney Ni. After the catalyst was reused for 6 times its activity and selectivity did not decrease significantly.