Abstract: The activity of Pd/WO3-ZrO2 catalysts in the reaction of heptane isomerization is determined by a complex of acid sites, primarily by the presence of LAS on the catalysts surface formed by the inclusion of W5+ atoms in their composition. This type of acid sites ensures high heptane conversion and acceptable selectivity in the formation of heptane isomers. The contribution of these acid sites to the activity of catalysts can be optimized at the stages of high-temperature activation in a hydrogen flow. The optimal temperature conditions for H2-activation should be chosen in the average temperature range of 200–300 ◦С, sufficient to achieve a fraction of W5+ atoms on the catalyst surface of ca. 35% (at. W5+/at. W6+). The second group includes Lewis acid sites, which are formed upon the introduction of palladium into the composition of the tungstated zirconia catalyst. The optimal loading of Pd is ca. 0.1 wt.%; above this amount, the acid sites are covered with dispersed palladium, which leads to a decrease in the total acidity of the catalyst. Stabilization of medium strength acid sites on the catalysts surface after the addition of Pd to the catalyst ensures the heptane isomerization reaction in hydrogen atmosphere at a moderate temperature of 200 ◦C with a high selectivity of 91.1–91.7%.

Cite: Smolikov M.D. , Shkurenok V.A. , Bikmetova L.I. , Prosvirin I.P. , Gulyaeva T.I. , Bukhtiyarov A.V. , Paukshtis E.A. , Bukhtiyarov V.I. , Lavrenov A.V.
Effect of hydrogen reduction and palladium promotion of tungstate-modified zirconia on isomerization of heptane
Molecular Catalysis. 2022. V.529. 112527 :1-13. DOI: 10.1016/j.mcat.2022.112527 WOS Scopus РИНЦ OpenAlex

Dates:

Submitted:	May 6, 2022
Accepted:	Jul 19, 2022
Published online:	Jul 28, 2022
Published print:	Aug 1, 2022

Identifiers:

Web of science:	WOS:000843502500004
Scopus:	2-s2.0-85135114192
Elibrary:	50366098
OpenAlex:	W4288421623

Citing:

DB	Citing
Scopus	7
Web of science	2
OpenAlex	9

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