Trends offered by ionic liquid-based surfactants: Applications in stabilization, separation processes, and within the petroleum industry

Ionic liquid (IL)-based surfactants exhibit prominent properties in adsorption and aggregation, providing strong influence on interfacial properties of phases. This review overviews the main characteristics of IL-based surfactants and their versatility in different processes particularly those dealing with the stabilization of immiscible liquids and solids for the aim of producing microemulsions and micelles. Applications in separation processes for chromatographic and extraction techniques and in the petroleum industry for augmenting the oil recovery, separation of asphaltene and paraffin deposits and crude oil separation are precisely studied by describing the mechanisms as well as qualitative and quantitative comparison to conventional surfactants everywhere relevant. These are particularly highlighted with respect to the importance of selecting/tailoring the desired IL-based surfactants in relation to the influence of operating parameters. Moreover, challenges and directions of the future outlooks on specific topics are discussed.