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 °C in front-end processes. Selective acetylene hydrogenation catalysts with an OW wider than 100 °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 β-PdH x , PdBi/Calcite exhibit >99% selectivity to C 2 H 4 in the whole temperature range tested (50–300 °C) and ~100% C 2 H 2 conversion from 150 to 300 °C. Finally, as a result, an operation window exceeding 150 °C has been achieved.