Neftyanaya Provintsiya 


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

R.R. Zakieva, N.Yu. Bashkirtseva

DOI: https://doi.org/10.25689/NP.2021.1.141-149


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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

E-mail: zakieva.r.r@yandex.ru


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

E-mail: bashkircevan@bk.ru

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 https://doi.org/10.25689/NP.2021.1.141-149 (in Russian)


   © R.R. Zakieva, N.Yu. Bashkirtseva, 2021

       This is an open access article under the Creative Commons Attribution 4.0 License (https://creativecommons.org/licenses/by/4.0/)