Selective hydrogenation of cinnamaldehyde over Pt/ZrO2 catalyst modified by Cr, Mn, Fe, Co and Ni

Hydrogenation properties of cinnamaldehyde (CMA) have been studied over Pt/ZrO2 and PtM/ZrO2 catalysts (M = Cr, Mn, Fe, Co and Ni) in ethanol at 343 K and 2.0 MPa. The effect of different content of Ni and base has also been investigated over PtNi/ZrO2 catalyst. With introduction of transition metals to Pt/ZrO2 catalyst shows a significant influence on the catalytic properties. PtCo/ZrO2 catalysts show the best yield of cinnamyl alcohol (CMO), and PtNi/ZrO2 catalyst shows good yield of hydrocinnamaldehyde (HCMA). In the presence of base solution, rate of the hydrogenation of CMA over PtNi/ZrO2(0.4 wt%) catalyst increases significantly and side reaction is remarkably inhibited. More bare metal atoms situated remote from the interface region on PtNi/ZrO2 catalyst surface are the reason of good selectivity of HCMA for PtNi/ZrO2 catalyst.