Potential applications of deep eutectic solvents in natural gas sweetening for CO₂ capture

Novel solvents named deep eutectic solvents (DESs) have been intensively investigated in recent years. Their non-toxicity, biodegradability, low volatility, easy preparation and low cost make them promising green solvents for several industrial processes. This article provides a status review of the possible applications of DESs in natural gas (NG) sweetening by carbon dioxide (CO₂) capturing. Investigations on preparation and chemical structures of DESs were reported. In addition, very recent physiochemical properties and applications of DESs were well discussed. Mainly, experimental and predicted solubilities of CO₂ in DESs were reported and compared in this work. It was deduced that DESs offer some potential advantages over the conventional solvents, i.e. alkanolamines, in terms of absorption efficiency, easy preparation and low economic cost. It is expected that in coming decades, DESs will offer potential use in NG technology. Further investigations are highly required to highlight more about these neoteric solvents.