Polythermal study of phase behavior and extractive crystallization of salt in the ternary system ammonium sulfate – water – polyethylene glycol-1500
Year: 2025
Type: article
Abstract: 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 stratification region on temperature has been found using the liquid phase volume ratio method. Isothermal phase diagrams of the studied ternary system have been constructed at 10.0, 20.0, 40.0, 50.0 and 70.0°C, the solubility of the components has been determined. It has been found that in the range of 10.0–40.0° C, a triangle of the eutectic state exists on the isothermal diagrams. At all temperatures of the study range, a monotectic triangle with adjacent fields of saturated solutions and stratification is realized on the isotherms. The coefficients of PEG-1500 distribution between the equilibrium liquid phases of the monotectic state have been calculated. It has been found that ammonium sulfate effectively salts out PEG-1500 in the range of 10.0–70.0° C, while the content of the organic component in the aqueous phase is minimal (0.1–0.2 wt.%). Mixtures of the components of the studied system can be recommended for the extraction of hydrophilic molecules without introducing other compounds. It has been found that PEG-1500 exhibits high efficiency as an ammonium sulfate antisolvent, which allows this salt to be extracted with high yields from unsaturated aqueous solutions at temperatures close to the standard one. With a decrease in temperature and an increase in the content of PEG-1500 in the water-salt mixture, the yield of salt crystals increases. It has been found that for a 38 wt.% ammonium sulfate solution with the introduction of 60 wt.% PEG-1500, the maximum yield of salt crystals (96.4%) has been observed at 30.0° C.
Authors: Madina A. Karagulova, Diana R. Kirilina, PJSC “Ozon Pharmaceuticals”, Veronica V. Danilina, Victoria M. Tsesarenkova, Dmitry G. Cherkasov
Language: English
Subfield: Filtration and Separation
Field: Chemical Engineering
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W4412199008