Phase Diagram for the Hexane-Acetonitrile-Tri-n-butyl Phosphate-Solvated Neodymlum(III) Nitrate Ternary Liquid System

摘要

Phase diagrams of the hexane-acetonitrile-[Nd(NO_3)_3(TBP)_3] liquid ternary system were studied at various temperatures. The system consists of two pairs of incompletely miscible liquids: hexanc-acetonitrile and [Nd(NO_3)_3(TBP)_3]-hexane. The two-liquid field in the (Nd(NO_3)_3(TBP)_3]-hexane system decreases with increasing temperature; the upper critical solution temperature T_(cr) = 316.15 +- 0.25 K. The temperature effect on the immiscibility field in the hexane-acetonitrile system is insignificant. The title ternary liquid system is characterized by two homogeneous liquid fields and one two-phase liquid field at T < 316 K. One phase is depleted of acetonitrile and contains variable proportions of [Nd(NO_3)_3(TBP)_3] and hexane; the other contains variable proportions of acetonitrile and [Nd(NO_3)_3(TBP)_3] and a small proportion of hexane. With rising temperature, the two-phase field narrows and deforms, whereas the homogeneous liquid fields expand. At T> 337 K, the system transforms into a ternary liquid system with one pair of incompletely miscible liquids (hexane-acetonitrile).