Synthesis and Characterization of Sibunit-Supported Pd-Ga, Pd-Zn, and Pd-Ag Catalysts for Liquid-Phase Acetylene Hydrogenation

Pd/Sibunit and Pd-M/Sibunit (M = Ga, Zn, or Ag) catalysts have been synthesized, and their catalytic properties in liquid-phase acetylene hydrogenation have been investigated. Doping of the palladium catalyst with a metal M leads to the formation of the Pd2Ga, PdZn, or Pd0.46Ag0.54 bimetallic compound. The bimetallic particles are much smaller (1.6-2.0 nm) than the monometallic palladium particles (4.0 nm). Doping with zinc raises the ethylene selectivity by 25% without affecting the activity of the catalyst. Specific features of the effect of each of the dopants on palladium are reported.