Neftyanaya Provintsiya
electronic peer-reviewed scholarly publication
Neftyanaya provintsiya No.1(25),2021

Upgrading of ultra-viscous oil in sub- and supercritical aqueous fluid

R.R. Zakieva, N.Yu. Bashkirtseva


This paper considers heavy oil aquathermolysis experiments in supercritical water conducted on reaction mixtures containing heavy oil, carbonaceous materials, and catalytically active rock-forming minerals.

The main characteristic feature of supercritical aquathermolysis products is increased content of paraffinic/naphthenic hydrocarbons: up to 76.2 wt% and 68.2 wt% for aquathermolysis products 4 and 5, respectively, compared to the original 40.8 wt%; whereas resin and aromatic fractions reduce. Aquathermolysis product 4 exhibits reduction of the aromatic and resin content from 13.7 to 4.1 wt% and from 37.8 to 13.1 wt%, respectively. Equidirectional change in the asphaltene content is also observed in aquathermolysis products: in experiments with hard coal (experiments 1 and 3) it has increased up to 9.9 and 9.2 wt%, respectively, compared to the original 7.7 wt%.

It has been demonstrated that aquathermolysis processes involve destruction of highmolecular-weight components and formation of normal and branched alkanes that have been absent in the original oil sample.

Resultant experimental data has been used to develop a process flow diagram of supercritical fluid technology for practical applications.

    Key words:

    ultra-viscous oil, asphaltene, aquathermolysis, oil upgrading, supercritical aqueous fluid


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    R.R. Zakieva, Kazan National Research Technological University
    68, K. Marx st., Kazan, 420015, Russian Federation

    N.Ju. Bashkirceva, Dr.Sc., Professor, Dean of Petroleum and Petrochemistry Faculty, Kazan National Research Technological University
    68, K. Marx st., Kazan, 420015, Russian Federation

    For citation:

    R.R. Zakieva, N.Yu. Bashkirtseva Oblagorazhivanie sverhvjazkoj nefti v sub- i sverhkriticheskom vodnom fljuide [Upgrading of ultra-viscous oil in sub- and supercritical aqueous fluid]. Neftyanaya Provintsiya, No. 1(25), 2021. pp. 141-149. DOI (in Russian)

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