Quantum chemical analysis of mechanisms of phenylacetylene and styrene hydrogenation to ethylbenzene on the Pd{111} surface

Journal Article · Thu Mar 15 04:00:00 EDT 2018 · Russian Chemical Bulletin

DOI:https://doi.org/10.1007/S11172-018-2088-5· OSTI ID:22863366

Danilov, F. O.; Flid, V. R. ^[1]

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1. Moscow Technological University (M. V. Lomonosov Institute of Fine Chemical Technologies) (Russian Federation)

The mechanisms of the hydrogenation of phenylacetylene and styrene to ethylbenzene on the Pd{111} surface, which are secondary reactions of the selective hydrogenation of phenylacetylene, were studied by the DFT-PBE method. The position of the Ph group of the styrene molecule with respect to the Pd surface is shown to exert a noticeable effect on the mechanism of the process. If the Ph group is adsorbed on the Pd surface, then the addition of the first H atom to the terminal C atom of the styrene molecule is most probable. If Ph does not contact the surface, then the most substituted C atom of the styrene molecule is first hydrogenated. On the whole, the interaction of the Ph group with the Pd{111} surface results in stable adsorption structures, the hydrogenation of which on the Pd{111} surface is strongly hindered. The Gibbs activation energy (ΔG{sup ≠}{sub 298}) is 22.9 and 27.1 kcal mol{sup –1} in the most probable reaction routes of styrene hydrogenation to ethylbenzene and direct hydrogenation of phenylacetylene to ethylbenzene, respectively.

• OSTI ID: 22863366
• Journal Information: Russian Chemical Bulletin, Journal Name: Russian Chemical Bulletin Journal Issue: 3 Vol. 67; ISSN RCBUEY; ISSN 1066-5285
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
ACTIVATION ENERGY
ADSORPTION
ALLYL RADICALS
BENZENE
CARBON
CHEMICAL ANALYSIS
DENSITY FUNCTIONAL METHOD
HYDROGENATION
INTERACTIONS
MOLECULES
PALLADIUM
PHENYL RADICALS
SECONDARY REACTIONS
STYRENE
TOLAN