International team studies the role of water in the process of desulfurization of hydrocarbon resource components

The paper was published in Chemical Engineering Journal.

Technologies of underground partial refining of heavy oil are a promising area of the oil and gas industry. As the Laboratory of In-Situ Combustion has shown, an important role in these processes is played by water, which acts not only as a medium, but also participates in chemical processes as a reagent in hydrothermal desulfurization.

This new research unveils data for the understanding of chemical transformations in the oil reservoir during hydrothermal action with the use of catalytic compositions. This in turn has important practical implications for the oil and gas industry, enabling the efficient and environmentally friendly processing of heavy oils, reducing sulfur content and improving product quality.

"The innovativeness of the work lies in the use of isotope tags to evaluate the role of water as a chemical agent in hydrothermal desulfurization processes. This is the first time this approach has been used to study the mechanism of interaction between water and oil sulfur compounds. The additional use of nickel stearate as an oil-soluble catalyst showed a significant improvement in the process, opening new perspectives for the application of catalysts in hydrothermal conditions," says Junior Research Associate Ameen Al-Muntasser.

The role of water in the processes of hydrothermal desulfurization of model oil components was confirmed by a complex of physical and chemical methods of analysis. The research team was able to achieve a high degree of desulfurization by using nickel stearate as a petroleum-soluble catalyst precursor, which increased the conversion rate to 97.34 percent.

"The important findings on the role of water in catalytic and non-catalytic hydrothermal desulfurization processes not only enrich the theoretical basis in this field, but also justify the combined use of water vapor injection and catalysts to improve the conversion and desulfurization performance of heavy crude oil, thereby offering ideas for optimizing the methods of unconventional hydrocarbon resource development," explains Junior Research Associate Zhou Xiaodong.

Additionally, it was found that nickel stearate is converted into sulfide and polysulfide particles during hydrothermal action, which has an impact on the rate of the processes under investigation.

"In this work we have carried out a whole complex of experimental and theoretical studies, which allows us to understand the mechanisms of chemical processes occurring during hydrothermal action on heavy oils, which are complex systems. For this purpose, model sulfur-containing components were used. It is important to note the efficiency of catalytic additives that can be used for industrial applications," adds project lead, Chair of the Department of Petroleum Engineering Mikhail Varfolomeev.

Apart from KFU, the paper saw contributions from Niroo Research Institute (Iran) and Skolkovo Institute of Science and Technology (Russia).

More information:
Hydrogen-donating capacity of hydrothermal system in catalytic and non-catalytic desulfurization of sulfur compound of unconventional crudes and residues: Deuterium tracing study
www.sciencedirect.com/science/ … ii/S1385894724051155

Provided by Kazan Federal University