The effect of supports on hydrogenation and water-tolerance of copper-based catalysts.

The effect of supports (SiO₂, ZnO, ZrO₂ and Al₂O₃) on the hydrogenation and water-tolerance of copper catalysts were studied at reaction condition containing water. The copper catalysts with different supports showed different hydrogenation and water-tolerance performances. The result of XRD, BET, Raman, TPR, XPS, N₂O titration and TEM confirmed the interactions between copper and supports, and the formation of Cu–M_xO_y (M = Zn, Zr, and Al) interfaces had great effects on the catalytic activity and water-tolerance performance. In particular, too strong interactions suppressed the reduction of copper oxides, resulting in a low catalytic activity. Nevertheless, the formation of Cu–M_xO_y could provide more active sites, which provided more chances for the reactants to touch the active sites. By this method, the loss of active sites due to competitive adsorption between water and ethyl acetate could be made up, so that the water-tolerance of copper catalysts was improved. [ABSTRACT FROM AUTHOR]