Formulation study on blended salt-tolerant surfactant nanoscale emulsions with tunable hydrophilic heads for application in high-salinity reservoirs
Li X. Kang W. Aidarova S. Xu D. Sarsenbekuly B. Wei J. Zhang G.
1 January 2026American Institute of Physics
Physics of Fluids
2026#38Issue 1
Recent studies indicate that surfactant application in high-salinity reservoirs is limited by the poor solubility and weak interfacial activity of conventional formulations. Hydrophilic-head modification improves brine compatibility, while blending different types of anionic surfactants with complementary headgroup properties enables precise tuning of head composition for better oil–water balance. However, systematic studies on hydrophilic-head-modified binary systems remain scarce. To evaluate salt-tolerant formulations, a structured workflow was applied. Binary blends of G5 and the propylene oxide unit (PO)-head-modified G9 were screened by varying blend ratios to achieve ultralow interfacial tension (IFT). Interfacial and wettability tests under high-salinity and elevated-temperature conditions determined operating ranges and rock–fluid interactions, while emulsion stability and droplet morphology were analyzed via microscopy and zeta-potential measurements. Core flooding with reservoir cores validated enhanced oil recovery performance. The designed binary system achieved ultralow-IFT values down to 1.86×10−4mN/m, far outperforming single components. Hydrophilic-head modification improved solubility and salt tolerance, while the complementary interfacial roles of G5 (linear alkylbenzene sulfonate (LAS)-type) and G9 (PO-head-modified) enhanced dispersion-anchoring behavior at the interface. Wettability alteration toward a more water-wet state and stable oil-in-water emulsions with narrow droplet distributions confirmed favorable interfacial conditions. Core flooding demonstrated an additional 12.2% recovery after waterflooding, aligning with interfacial and emulsion results. The findings verify that combining a PO-head-modified surfactant with a LAS-type surfactant provides an effective, thermally stable formulation for high-salinity reservoirs in Kazakhstan and offers a rational framework for surfactant design in challenging environments.
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Kazakhstan-British Technical University, Almaty, 050000, Kazakhstan
Xinjiang Keli New Technology Development Co. Ltd., Xinjiang, Karamay, 834000, China
School of Petroleum, China University of Petroleum Beijing at Karamay, Karamay, 834000, China
Kazakhstan-British Technical University
Xinjiang Keli New Technology Development Co. Ltd.
School of Petroleum
10 лет помогаем публиковать статьи Международный издатель
Книга Публикация научной статьи Волощук 2026 Book Publication of a scientific article 2026