Institute of Chemistry and Chemical Technology at the Siberian Branch of the Russian Academy of Sciences, Federal Research Center Krasnoyarsk Science Center of the Siberian Branch of the Russian Academy of Sciences, Krasnoyarsk, Russia¹ ; Siberian Federal University, Oil and Gas Institute, Krasnoyarsk, Russia²:

P. N. Kuznetsov, Lead Researcher¹, Professor², Doctor of Chemical Sciences, e-mail: kpn@icct.ru

A. V. Obukhova, Research Fellow¹, Associate Professor², Candidate of Chemical Sciences, e-mail: lab9team@icct.krasn.ru

Institute of Chemistry and Chemical Technology of the Mongolian Academy of Sciences, Ulaanbaatar, Mongolia:

B. Avid, Principal Researcher, Doctor of Chemical Sciences

Institute of Chemistry and Chemical Technology at the Siberian Branch of the Russian Academy of Sciences, Federal Research Center Krasnoyarsk Science Center of the Siberian Branch of the Russian Academy of Sciences, Krasnoyarsk, Russia:
L. I. Kuznetsova, Lead Researcher, Candidate of Chemical Sciences, e-mail: kuzpn@icct.ru

In recent years, the electrolysis industry has been experiencing a progressive shortage of coal-tar pitch binder required for making anodes, which can be attributed to a steady and irreversible decline in coal-tar pitch production. This negative trend undermines the prospective development of aluminum electrolysis industry and determines an urgent need to develop methods for obtaining alternative binders for carbon electrodes. This paper substantiates the prospects of a method for obtaining environmentally friendly pitch binders by solvolysis of coals at low temperature and pressure. Criteria have been developed for selecting coals for obtaining soluble polyaromatic substances with a yield of up to 80% (against 5% in coal coking). The paper describes the chemical composition, molecular structure and technical properties of extractive pitch substances obtained by solvolysis of coal in the medium of commercial hydrocarbon solvents, and a comparison is made with commercial samples of coal-tar pitch, petroleum pitch and coal/petroleum compound pitch. It is shown that extractive pitches do meet the requirements set to anode binders, which was confirmed by a model anode sample prepared using alternative pitch. An important advantage of extractive pitch is a low concentration of benzo(a)pyrene (times less than in coal tar pitch).
This research was carried out under Project No. FWES-2021-0014 assigned to the Institute of Chemistry and Chemical Technology at the Siberian Branch of the Russian Academy of Sciences (EGISU Registration No.: 121031500206-5).

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