AbstractBenzalacetone was hydrogenated using a Raney nickel catalyst, and various amounts of HCl, NaCl and H3PO4 in ethyl alcohol were added to test their inhibiting effect on catalytic activity. In the presence of HCl and H3PO4, Raney nickel lost its catalytic activity, and the rate of hydrogenation was decreased, but NaCl had no effect. While the hydrogenation of the ethylenic bond of benzalacetone was retarded, the decrease in hydrogen uptake by the carbonyl group was affected much more, and the amount of alcohol produced was markedly reduced.