Co-B/SiO_2非晶态催化剂用于肉桂醛选择性加氢制备肉桂醇的研究

Study on the Selective Hydrogenation of Cinnamaldehyde to Cinnamyl Alcohol over the Co-B/SiO_2 Amorphous Catalyst

采用化学还原法制备了Co B/SiO2 非晶态催化剂 ,测定了其在液相肉桂醛 (CMA)选择性加氢反应中的催化活性以及不同反应时间内CMA的转化率和对肉桂醇 (CMO)选择性 .研究表明 :(1)Co B/SiO2 非晶态催化剂中 ,最佳Co负载量为w =3.7% ,反应 3h后 ,CMO的得率可达到 78.7% ,此时 ,CMA的转化率为 93.3% ,对CMO的选择性达 83.3% ;(2 )Co B/SiO2 非晶态催化剂的热处理晶化导致其催化活性和选择性显著下降 ;(3)Co B/SiO2 非晶态催化剂的催化性能明显优于其他Co 基催化剂 ,包括晶态Co B/SiO2 、Co/SiO2 和RaneyCo催化剂 .通过动力学研究以及催化剂的系列表征 ,如ICP、XRD、DSC、SEM、XPS等 ,初步讨论了Co B/SiO2

The Co B/SiO 2 amorphous catalyst was prepared via chemical reduction and was employed in the liquid phase selective hydrogenation of cinnamaldehyde(CMA) to cinnamyl alcohol(CMO).Its activity,the conversion of CMA and the selectivity to CMO at different reaction time were measured.The optimum Co loading of the Co B/SiO 2 amorphous catalyst was determined as 3.7%( w (Co)),over which,the CMO yield may reach 78.7% with the CMA conversion of 93.3% and the CMO selectivity of 83.3%.When the Co B/SiO 2 amorphous catalyst underwent the heating treatment,its activity and selectivity to CMO decreased considerably dur to the crystallization.In comparison with other Co based catalysts,such as the crystallized Co B/SiO 2,Co/SiO 2 and Raney Co catalysts.It was found that the Co B/SiO 2 amorphous catalyst exhibited much higher activity better selectivity to CMO.The correlation of the superior catalytic properties of the Co B/SiO 2 catalyst to its amorphous structure and surface electronic state was discussed briefly based on the kinetic studies and various characterizations,including ICP,DSC,SEM,XPS,XRD.