Double Electrostatic Shielding: A New Strategy for the Improvement of Micelle Stability

Summary Oil occupies an important position in the global energy structure, but the recovery rate of traditional extraction methods is gradually decreasing, and a large amount of crude oil remains in reservoirs. To improve oil recovery, researchers are exploring new technologies, among which the worm-like micelle system (VES-G2) has attracted attention due to its unique rheological properties and excellent oil displacement performance. This system can maintain good stability performance in complex reservoir environments. Calcium chloride and sodium benzenesulfonate form a dual electrostatic shielding effect, which can effectively shorten the distance between hydrophilic head groups, reduce molecular thermal motion, enhance intermolecular interactions, and form a stable micelle structure. However, the increase in temperature will weaken stability, leading to increased molecular thermal motion and loose aggregation morphology. Experiments have shown that the combination of 0.2% sodium benzenesulfonate and 30% calcium chloride can significantly improve the temperature and shear resistance of VES-G2 solution, enabling it to maintain high viscosity and stability under high-temperature and -pressure conditions. This study provides a theoretical basis for optimizing the stability of the VES-G2 system and has the potential application value for improving oil recovery technology.