Molecular understanding of alkyne hydrogenation for the design of selective catalysts

The gas-phase hydrogenation of propyne to propene was investigated over a series of heterogeneous catalysts based on Pd (in the absence and the presence of CO), Ni, Au, Cu, and Cu-Ni. Catalytic tests in a continuous flow micro-reactor at ambient pressure and density functional theory (DFT) calculations were combined to understand complex structure-selectivity-activity relationships and their dependence on key experimental variables such as H-2/alkyne and CO/H-2 ratios. The wide scope of our work enables the identification of similarities and differences between these systems and paves the way to design more selective catalysts.