Thermal Diffusion Separation of Petroleum Diamondoids and Protodiamondoids

Thermal Diffusion Separation of Petroleum Diamondoids and Protodiamondoids

Separation

Aromatic compounds

Petroleum chemistry

Isomers

Aluminum compounds

Thermal diffusion in liquids

Isomerization

Abstract: Diamondoids were separated from protodiamondoids (precursors of diamondoids)in a saturated fraction (150350C) of crude oil by thermal diffusion. It wasfound that in the course of thermal diffusion separation,C10C13 adamantanes(tricyclo[3,3,1,13,7]decanes) andC14C16 diamantanes(pentacyclo[7,3,1,14,12,02,7,06,11]tetradecanes)are separated from the corresponding protoadamantanes and protodiamantanes anddescend to the lower sections of the thermal diffusion column. In contrast toadamantanes and diamantanes,C18C19 triamantanes(heptacyclo[7,7,1,13,15,01,12,02,7,04,13,06,11]octadecanes)are not separated from prototriamantanes and are concentrated in the lowersections of the thermal diffusion column. Catalytic isomerization of thisthermal diffusion fraction with aluminum bromide was carried out to furtherconfirm that the numerous compounds that have the same characteristic ions astriamantanes but elute later are polycyclic (most likely bridged) hydrocarbons,specifically prototriamantanes. As a result, all these polycyclic compounds wereisomerized into triamantanes. Similarly, in the course of isomerization ofthermal diffusion fractions containing protoadamantanes and protodiamantanes,all of these turned into adamantanes and diamantanes, respectively. 2021, The Author(s).

147-151

2

61

Petroleum Chemistry

2021

Gadzhiev, G.A.

Badmaev, Ch. M.

Gordadze, G.N.

Giruts, M.V.

journalArticle

9655441

10.1134/S0965544121020110