Highly Selective Acetylene Semihydrogenation Catalyst with an Operation Window Exceeding 150 °C

The operating window (OW) is a primary performance criterion for the selective hydrogenation of acetylene in excess ethylene. Currently, most state-of-the-art catalyst systems have an OW of less than 50 degrees C in front-end processes. Selective acetylene hydrogenation catalysts with an OW wider than 100 degrees C are rare. Here, we demonstrate a facile stepwise chemical method to synthesize calcite-supported PdBi intermetallic compounds (PdBi/Calcite) that feature isolated and electron-rich Pd atoms as active sites for acetylene hydrogenation. Beneficial from the extremely weak ethylene absorption abilities and the stable structures against the formation of beta-PdHx, PdBi/Calcite exhibit >99% selectivity to C2H4 in the whole temperature range tested (50-300 degrees C) and similar to 100% C2H2 conversion from 150 to 300 degrees C. As a result, an operation window exceeding 150 degrees C has been achieved.

Automated summary

A facile stepwise chemical method was employed to synthesize PdBi/Calcite catalysts with isolated and electron-rich Pd atoms as active sites, which exhibited >99% selectivity to C2H4 in a wide temperature range and achieved an operating window exceeding 150 degrees C.