Cationic Gemini Surfactants in the Oil Industry: Applications in Extraction, Transportation and Refinery Products

The petroleum industry faces intensifying challenges related to the depletion of easily accessible reservoirs and the growing energy demand, necessitating the adoption of ad-vanced chemical agents that can operate under extreme conditions. Cationic gemini sur-factants, characterized by their unique dimeric architecture consisting of two hydrophilic head groups and two hydrophobic tails, have emerged as superior alternatives to con-ventional monomeric surfactants due to their enhanced interfacial activity and physico-chemical resilience. This review provides a comprehensive analysis of the literature concerning the molecular structure, synthesis, and functional applications of cationic gemini surfactants across the entire oil value chain, from extraction to refining. The analysis reveals that gemini surfactants exhibit critical micelle concentrations signifi-cantly lower than their monomeric analogues and maintain stability in high-temperature and high-salinity environments. They demonstrate exceptional efficacy in enhanced oil recovery through ultra-low interfacial tension reduction and wettability alteration, while simultaneously serving as effective drag reducers, wax inhibitors, and dual-action bio-cidal corrosion inhibitors in transportation pipelines. Cationic gemini surfactants repre-sent a transformative class of multifunctional materials for the oil industry.