Tri(1-ethyl-3-methylimidazolium) gadolinium hexachloride ([emim](3)[GdCl6]), tri(1-butyl-3-methylimidazolium) hexagadolinium chloride ([bmim](3)[GdCl6]), di(tetramethylammonium) manganese tetrachloride ([TMA](2)[MnCl4]) and cholinium tetrachloroferrate ([Chol][FeCl4]) were synthetized and their solubility in water, ethanol, 1-propanol and 1-butanol were determined as a function of temperature. Activity coefficients were calculated and their comparison with ideal solutions is discussed. The experimental data were correlated successfully by means of the semi-empirical Grant equation. In addition, melting point depression effect of high pressure carbon dioxide was studied. (C) 2013 Elsevier Ltd. All rights reserved.