Activation of the Highly‐Selective Pd₁₁Bi₂Se₂ during the Semi‐Hydrogenation of Acetylene

Abstract

Pd11Bi2Se2 was prepared as single‐phase material and used in an unsupported state as catalyst in the semi‐hydrogenation of acetylene in ethylene excess. After an initial inactive time‐period, Pd11Bi2Se2 activated and showed high acetylene conversion and selectivity towards ethylene at 473 K. In addition, after the initial inactive state, the compound revealed high stability during 100 h time on stream. At 80 % conversion the selectivity to ethylene is higher than 90 %. Post‐catalysis investigations by powder X‐ray diffraction (p‐XRD) and X‐ray photoelectron spectroscopy (XPS) exclude the formation of intermetallic hydrides, decomposition, and the presence of elemental palladium. Furthermore, comparison of XPS before and after catalysis revealed the reason of the inactive state of the intermetallic compound during the first hours of catalysis. An initial surface layer of bismuth oxide is reduced and re‐incorporated into the intermetallic compound. This material change is responsible for the initially observed activation of Pd11Bi2Se2 during the semi‐hydrogenation of acetylene.

Pd–In intermetallic nanoparticles with high catalytic selectivity for liquid-phase semi-hydrogenation of diphenylacetylene

“…[11][12][13] Many efforts have been devoted to synthesize and optimize Pd catalysts by bimetallic Pd-M alloys (e.g. with M = Cu, 14 Ag, [15][16][17] Au, 18,19 Zn, 20 Ga, 21 In, [22][23][24] Sn, 25,26 or Bi) 27 or even ternary Pd-based phases (such as Pd-Bi-Se 28 or Pd-Ga-Sn), 29,30 improving catalytic selectivity for the selective hydrogenation of alkynes. In addition, non-precious, binary alloys (Ni/Fe), 31 intermetallic compounds (Al 13 Fe 4 ), 32 transition metal-free Zintl phases (BaGa 2 ), or non-precious, ternary phases (Cu-Ni-Fe) 33 have been reported as interesting catalytic materials for alkyne semi-hydrogenation in the gas or liquid phase.…”

Pd/Ag Nanoparticles Prepared in Ionic Liquids as Model Catalysts for the Hydrogenation of Diphenylacetylene

“…Economic aspects associated with the high Pd loading and the toxicity of lead together with stricter environmental regulations have driven the search for new alternatives [15,19]. The selectivity to alkenes is also significantly improved for binary bimetallic Pd-M particles (e.g., with M = Cu [20], Ag [21][22][23], Au [24], Zn [6], Ga [25,26], In [27][28][29], Sn [30], or Bi [31]) or even ternary Pd-based phases (such as Pd-Bi-Se [32] or Pd-Ga-Sn [33,34]). In addition, non-precious, binary alloys (Ni-Fe or Ni-Ga) [35,36], intermetallic compounds (Al 13 Fe 4 ) [37], transition metal-free Zintl phases (BaGa 2 ), or non-precious, ternary phases (Cu-Ni-Fe) [38] have been reported as catalysts for semi-hydrogenation of alkynes in the gas or liquid phase.…”