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Updated: Mar 3, 2026
Synthesis and Testing of Supported Pt-Cu Solid Solution Nanoparticle Catalysts for Propane Dehydrogenation
Published on: July 18, 2017
Pairwise hydrogen addition in the selective semihydrogenation of alkynes on silica-supported Cu catalysts
Oleg G Salnikov1,2, Hsueh-Ju Liu3, Alexey Fedorov3
1International Tomography Center , SB RAS , 3A Institutskaya St. , 630090 Novosibirsk , Russia .
Abstract:
Mechanistic insight into the semihydrogenation of 1-butyne and 2-butyne on Cu nanoparticles supported on partially dehydroxylated silica (Cu/SiO2-700) was obtained using parahydrogen. Hydrogenation of 1-butyne over Cu/SiO2-700 yielded 1-butene with ≥97% selectivity. The surface modification of this catalyst with tricyclohexylphosphine (PCy3) increased the selectivity to 1-butene up to nearly 100%, although at the expense of reduced catalytic activity. Similar trends were observed in the hydrogenation of 2-butyne, where Cu/SiO2-700 provided a selectivity to 2-butene in the range of 72-100% depending on the reaction conditions, while the catalyst modified with PCy3 again demonstrated nearly 100% selectivity. Parahydrogen-induced polarization effects observed in hydrogenation reactions catalyzed by copper-based catalysts demonstrate the viability of pairwise hydrogen addition over these catalysts. Contribution of pairwise hydrogen addition to 1-butyne was estimated to be at least 0.2-0.6% for unmodified Cu/SiO2-700 and ≥2.7% for Cu/SiO2-700 modified with PCy3, highlighting the effect of surface modification with the tricyclohexylphosphine ligand.
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