Phase diagrams and liquid-liquid-solid equilibrium (LLSE) data of the aqueous polypropylene glycol (PPG)400 + sodium sulfate, PPG400 + sodium carbonate, and PPG400 + sodium nitrate systems have been determined experimentally at 25 ° C. The effect of the type of salt on the binodal and tie lines has been studied, and the salting-out power of the salts in these systems was determined. Furthermore, a three-parameter equation and the Othmer-Tobias-Bancroft equations have been used for the correlation of the binodals and tie lines, respectively.