Abstract: The liquid-phase hydrogenation of diphenylacetylene (DPA) over 1 wt% Pd/Al2O3 catalysts with the mean palladium cluster size varying from 1.9 to 20 nm was studied at 5 bar H2 pressure and 25 °C. Hydrogenation of the triple bond was found to be structure sensitive and turnover frequency increased as Pd cluster size increased, while TOF in hydrogenation of the intermediate stilbene was essentially independent on the cluster size. Selectivity to stilbene was rather high (90–94%) and tends to increase with an increasing of Pd particle size. A reaction network was proposed for diphenylacetylene hydrogenation involving formation of cis- and trans- stilbene and their subsequent hydrogenation. The effect of Pd nanoparticle size on the hydrogenation kinetics was analyzed and discussed using a geometric approach based on the respective contribution of low (edges, corners) and highly coordinated sites (terraces) for a cubooctahedral shape of metal clusters. A quantitative description of the concentration dependences was performed incorporating the Pd particle size in the rate equations through changes in dispersion and the ratio of sites of different coordination. An excellent correspondence between theory and experiments was demonstrated.

Cite: Markov P.V. , Mashkovsky I.S. , Bragina G.O. , Wärnå J. , Bukhtiyarov V.I. , Stakheev A.Y. , Murzin D.Y.
Experimental and Theoretical Analysis of Particle Size Effect in Liquid-Phase Hydrogenation of Diphenylacetylene
Chemical Engineering Journal. 2021. V.404. 126409 :1-11. DOI: 10.1016/j.cej.2020.126409 WOS Scopus РИНЦ ANCAN OpenAlex

Dates:

Submitted:	Mar 23, 2020
Accepted:	Jul 23, 2020
Published online:	Jul 30, 2020
Published print:	Jan 15, 2021

Identifiers:

Web of science:	WOS:000613197800006
Scopus:	2-s2.0-85089146062
Elibrary:	45440880
Chemical Abstracts:	2020:1572321
Chemical Abstracts (print):	174:283826
OpenAlex:	W3046680027

Citing:

DB	Citing
Scopus	16
Web of science	16
Elibrary	14
OpenAlex	17

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