Phase Behaviour of Surface Active Ionic Liquids for Enhanced Oil Recovery

Abstract

Chemical flooding with surfactants is well known to have huge potential in Enhanced Oil Recovery (EOR) processes. One of the main challenges for surfactant EOR is finding a surfactant or a surfactant blend able to generate a Winsor Type III microemulsion. The main objective of this thesis is to obtain optimal formulations with surface active ionic liquids (SAILs) able to improve current surfactant EOR methods. To achieve this goal, the phase behaviour of a set of SAILs or blends containing a SAIL has been studied in the presence of water or brine and oil at different temperatures and atmospheric pressure. Based on the results obtained, a formulation containing a blend of IOS15-18 and [C12mim]Br is suggested as the best option, since an ultra-low interfacial tension was achieved and an injectable optimal formulation, tolerant to divalent ions, was found at a particular salinity.