Catalysts for selective hydrogenation of acetylene: A review

Ethylene is a crucial industrial feedstock in the petrochemical sector. However, the presence of a small amount of acetylene impurities in ethylene products will directly affect the next application of ethylene. Acetylene semi-hydrogenation is an effective strategy to remove trace acetylene impurities (0.5–2.0%) from the ethylene stream to avoid poisoning the Ziegler-Natta catalyst. The development of cost-effective, highly selective, active and stable catalysts for acetylene semi-hydrogenation poses a significant challenge in this field. In this review, the mechanism of acetylene semi-hydrogenation is first introduced. Second, the recent progress in the different types of catalysts on semi-hydrogenation acetylene including the conventional catalysts, single atom catalysts, electrocatalysts and photocatalysts is summarized. Finally, the future prospects of acetylene semi-hydrogenation catalysts are provided. It is expected that this review will afford the researchers to understand and develop highly efficient catalysts on semi-hydrogenation acetylene.