Gold on carbon and titanium oxides composites: Highly efficient and stable acetylene hydrogenation in large excess of ethylene

Photocatalytically generated gold on carbon and TiO2 composites were used for acetylene hydrogenation in excess ethylene, in a way close to current industrial practices. The crystalline effect of TiO2 and the addition of Pd to supported Au catalysts on acetylene hydrogenation were investigated. Carbon and amorphous TiO2 supported Au were highly active, selective, and stable and possessed the highest ethylene yield of 83% at 210 °C with a H2/C2H2 ratio of 2/1 for selective hydrogenation of acetylene to ethylene. With further addition of Pd to the supported Au catalyst, ethylene yield reached a maximum value of 57% at 30 °C with a H2/C2H2 ratio of 2/1. The enhanced performance originated from small neutral Au nanoparticles and the formation of bimetallic Au–Pd catalyst. This report opens up promising possibilities for the design of highly efficient heterogeneous supported gold catalysts.