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Highlights: [•] Ammonium, iron and magnesium salts were selected as efficient salting-out agents. [•] Immiscibility regions were mapped together with the tie-lines. [•] Suitable correlation models were employed to describe the solubility data. [•] Phase segregation was investigated in terms of several thermodynamic parameters. [Copyright &y& Elsevier]

Abstract: The aggregation behavior of three 1-alkyl-3-methylimidazolium chloride ionic liquids, [C n C1im]Cl (with n =8, 10, 12), was probed at atmospheric pressure using density and speed of sound measurements in the 283.15> T/K>313.15 temperature range in aqueous solutions with mole fraction ranges of 0> x([C8C1im]Cl)>58·10−4, 0> x([C10C1im]Cl)>20·10−4, and 0> x([C12C1im]Cl)>4.8·10−4. The results were used to calculate partial molar volumetric data and the isentropic compressibility of the solutions, both of which can be used as relevant properties to probe aggregate formation. In this context, micelle formation, solvation phenomena and water structural changes within the solutions are discussed in terms of the temperature and concentration dependence of the calculated properties. [Copyright &y& Elsevier]

Abstract: During the last years, the extraction of biomolecules and chemicals by means of Aqueous Biphasic Systems (ABS) has triggered a renewed interest, making it necessary to characterize fully the solubility data of this kind of system. In this study, two surfactants belonging to Triton X series (Triton X-100 and Triton X-102) are proposed as candidates to form ABS, by adding different potassium-based salts (K3PO4, K2HPO4, K2CO3, K2S2O3 and K2SO3) at T =298.15K. Several equations were used to fit the solubility data which were previously obtained by means of the cloud point method. The different phase forming capacities were analyzed in the light of the Hofmeister series, the Effective Excluded Volume (EEV) theory and the molar Gibbs free energy of hydration (Δ hyd G). The Othmer–Tobias equation was proposed to correlate the tie-line data. [Copyright &y& Elsevier]