Bi-modified Cu-Based Catalysts for Acetylene Hydrogenation: Leveraging Dispersion and Hydrogen Spillover.

Removing trace acetylene from the ethylene stream through selective hydrogenation is a crucial process in the production of polymer-grade ethylene. However, achieving high selectivity while maintaining high activity remains a significant challenge, especially for nonprecious metal catalysts. Herein, the trade-off between activity and selectivity is solved by synergizing enhanced dispersion and hydrogen spillover. Specifically, a bubbling method is proposed for preparing SiO 2 -supported copper and/or bismuth carbonate with high dispersion, which is then employed to synthesize highly dispersed Bi-modified Cu x C-Cu catalyst. The catalyst displays outstanding catalytic performance for acetylene selective hydrogenation, achieving acetylene conversion of 100% and ethylene selectivity of 91.1% at 100 °C. The high activity originates from the enhanced dispersion, and the exceptional selectivity is due to the enhanced spillover capacity of active hydrogen from Cu x C to Cu, which is promoted by the Bi addition. The results offer an avenue to design efficient catalysts for selective hydrogenation from nonprecious metals.