Abstract:A series of PdZnx/Al2O3 bimetallic catalysts with different Pd:Zn molar ratios were prepared in a controlled manner by strong electrostatic adsorption for the selective hydrogenation of 1,4-butynediol (BYD), and the effect of Zn introduction on the catalytic hydrogenation was investigated. It was found that the addition of a small amount of Zn was able to maintain the catalyst at a high activity and substantially improve its selectivity for the intermediate cis-1,4-butenediol (cis-BED). The PdZn2/Al2O3 catalyst exhibited high catalytic activity with 89% conversion and selectivity for cis-BED (85%) at 50 °C, 1 MPa H2 pressure, and the contact time of 6 gcat.·h/mol. Combined with temperature-programmed reduction and X-ray photoelectron spectroscopy, it was found that the precursor was calcined at 400 ℃ and reduced at 400 ℃ to form the PdZn bimetallic catalyst. The doping of Zn atoms effectively modulated the geometrical and electronic effects of the Pd active sites, which effectively inhibited the over-hydrogenation of the intermediate products.