Deep eutectic solvents as sustainable solvents for industrial separation problems: A recent update

Deep eutectic solvents (DESs) are ionic liquid analogues that consist of Lewis or Brønsted acids and bases. These systems are characterized by a substantial decrease in melting points as compared to those of the neat constituents. Activity coefficients at infinite dilution of organic solutes is used as a screening tool for extracting solvents, an approach that is useful for identifying acceptable precursors and assessing separation performance in practical applications. This review assesses the effectiveness of DESs as solvents for chemical separations wherein the data is presented for the activity coefficients at infinite dilution for 33 solutes in different DESs at various temperatures. Additionally, the selectivities and capacities for various solute extraction problems are also appraised from the activity coefficients at infinite dilution at T = 323.15 K; capacity represents the solvent's ability to extract the component.