Study on the Selective Hydrogenation of Cinnamaldehyde over the Co-B/SBA-15 Amorphous Catalyst

A supported Co-B amorphous alloy catalyst with mesoporous structure was prepared by impregnating the SBA-15 support with aqueous CoCl2 solution,followed by reduction with KBH4 solution.Unlike the Co-B/SiO2 in which most Co-B alloy particles were dispersed on the outer surface,the Co-B particles in the Co-B/SBA-15 catalyst were mainly distributed homogeneously in the channels of the SBA-15 support.During liquid phase cinnamaldehyde (CMA) hydrogenation,the as-prepared Co-B/SBA-15 exhibited much higher activity and yield toward cinnamyl alcohol (CMO) than the conventional Co-B/SiO2,possibly owing to the high and homogeneous distribution of Co active sites on the support,and the regular and well-ordered large size pore channels which favored the diffusion and adsorption of CMA molecules.Perhaps,the difference in nature of the active centers of these two catalysts,such as the cluster structure and the electronic state of the active sites should also be considered in order to explain their different catalytic behaviors.