Aqueous Biphasic Systems (ABS) are suggested as a separation technique for a great diversity of compounds, making it necessary to characterise fully the solubility data of these kinds of systems. In this study, the non-ionic surfactants Tween 20 and Triton X-100 are proposed as candidates to form ABS, with different inorganic and organic salts ((NH4)(2)Fe(SO4)(2), MgSO4, (NH4)(2)HPO4, (NH4)(2)SO4, (NH4)(2)C4H4O6) at T = 298.15 K. All the solubility data were obtained by means of the cloud point method and the salting-out ability of salts was also evaluated in terms of the Gibbs free energy of hydration (Delta(G)(hyd)) and molar entropy of hydration (Delta(S)(hyd)). The Merchuk equation and some variations of this model have been used for correlating the solubility curve. The extraction capacity k was evaluated in terms of tie-lines (TL) data. (C) 2013 Published by Elsevier Ltd.