Topological transformation of the phase diagram of the potassium nitrate-water-n-butoxyethanol ternary system

Phase equilibria and critical phenomena in the potassium nitrate-water-n-butoxyethanol ternary system were studied by the visual polythermal method over the temperature range 10–150°C. In this system, the boundary binary liquid system is characterized by the presence of a closed stratification region. The temperature of the formation of a critical tie line of monotectic equilibrium (18.3°C) and solution compositions corresponding to the critical solubility points at various temperatures were determined. The n-butoxyethanol distribution coefficients between the aqueous and organic phases of the monotectic state were calculated at eight temperatures. n-Butoxyethanol salting out from aqueous solutions by potassium nitrate increased as the temperature grew. The generalized scheme of topological transformations of salt-binary solvent ternary system phase diagrams with salting out was substantiated and augmented.