extractive crystallization

Phase equilibria and solubility have been studied by the visual polythermal method in mixtures of components in nine sections of the composition triangle in the range of 10–70° C in the ternary system ammonium sulfate – water – polyethyleneglycol-1500 (PEG-1500). The dependence of the compositions of solutions corresponding to the critical solubility points of the stratifi cation region on temperature has been found using the liquid phase volume ratio method.

Phase equilibria in the ternary system sodium nitrate – water – dipropylamine where the constituent binary liquid system is characterized by a trend to form a lower critical solution temperature (LCST) were studied using the visual-polythermal method in the range ?10.0–90.0° C. It was found that the introduction of sodium nitrate into the water – dipropylamine system led to a significant decrease in the mutual solubility of the components.