Chemical Enhanced Oil Recovery Using Ionic Liquid-Based Surfactants

Critical challenges have forced the oil industry to improve chemical enhanced oil recovery (CEOR) processes using more effective materials. In this regard, ionic liquid-based surfactants (IL-based surfactants) with noteworthy features such as good interfacial activity, recyclability, environmentally friendliness, and stability at high temperatures and salinity can be considered as a significant option. While IL-based surfactants have been of interest in various fields, their applications in CEOR have not been systematically reviewed. In this frame, this chapter overviews the performance of IL-based surfactants in different portions of oil production. For this purpose, a brief explanation of the characteristics of the IL-based surfactants and their applicability in CEOR is first provided. Then, the performance of the IL-based surfactants in surfactant flooding, micellar flooding, and wettability alteration are surveyed in detail. Also, the activity of IL-based surfactants in all three regions has been monitored with the effect of the chemical structure, as well as comparing the performance of different types of IL-based surfactants. Relevantly, a comparison with conventional surfactants is also included. The crucial challenges and possible directions for the use of IL-based surfactants and the conclusions are summarized in the final section