A nonionic natural-based Gemini surfactant synthesized from rice bran oil and its application in enhanced crude oil recovery

This study addresses the challenge of using environmentally friendly materials and poor performance and high optimal concentration of natural and natural-based surfactants in enhanced oil recovery (EOR) process by synthesizing a novel, nonionic Gemini surfactant from rice bran oil as a natural and sustainable source, offering an alternative to traditional surfactants. Key tests, including critical micelle concentration (CMC) determination via surface tension, salt compatibility, adsorption onto porous media, wettability alteration, and carbonate plug injection, demonstrate the surfactant’s performance in EOR process. The problem of high interfacial tension (IFT) in oil reservoirs, which limits oil recovery, is mitigated using this surfactant due to its effective IFT reduction and stability in high-salinity environments. The surfactant achieved a low CMC of 975 ppm in the water–oil system at 75 °C, indicating efficient performance at lower concentrations than typical natural and natural-based surfactants. A minimum IFT value of 0.648 mN/m was obtained at optimum salinity. The surfactant was fully compatible with up to 80 K ppm salinity and relatively compatible with up to a salinity of 140,000 ppm. Following surfactant injection, oil recovery increased significantly, reaching a recovery factor of 73.3 % original oil-in-place (OOIP) with a 16.8 % improvement. This study demonstrates the potential of rice bran oil-derived Gemini surfactants as a natural-based, effective solution for EOR applications, advancing beyond conventional methods in the literature.