Physicochemcial analysis of the phase diagram of the ternary liquid system [Y(NO3)3(TBP)3]-tetradecane-[UO2(NO3)2(TBP)2

Abstract

The phase diagram of the ternary liquid system (TLS) [Y(NO3)3(TBP)3]-tetradecane-[UO2 · (NO3)2(TBP)2] (TBP is tri-n-butyl phosphate) at 298.15 K is constructed. The TLS is characterized by an area of homogeneous solutions and an area of two-phase liquid systems with one of the phases (I) enriched in [Y(NO3)3(TBP)3] and [UO2(NO3)2(TBP)2] and the other phase (II), in tetradecane. The inter-molecular interaction parameters and excess Gibbs energies (gE) for the binary systems and TLS along the binodal curve were calculated from data on the mutual solubility in the binary system [Y(NO3)3(TBP)3]-tetradecane and the ternary liquid system, using equations of the NRTL theory. For the binary system [Y(NO3)3(TBP)3]-[UO2(NO3)2(TBP)2], gE 0. An algorithm is given for computer calculation of the binodal curve and nodes for the TLS within the framework of NRTL equations using the intermolecular interaction parameters.