Bulk Properties of a Water–Urea–Choline Chloride System

Abstract

The authors analyze currently available experimental data on the densities of solutions of two binary water–choline chloride and urea–choline chloride subsystems, and a ternary water–urea–choline chloride system. Parameters of the Pitzer–Simonson–Clegg volumetric model are determined using only one function \({{V}_{m}} = f{\kern 1pt} \left( {~T,~p,{{x}_{1}},{{x}_{2}}} \right)\), which describes the experimental molar volumes of the solutions of the binary subsystems and ternary system in the 278.15 to 363.15 K range of temperatures and the 0.1 to 50 MPa range of pressures. Thermodynamic modeling reveals the dependence of the molar volume of a choline chloride melt on the parameters of state (p, T). The resulting model parameters describing binary interactions in the water–choline chloride and urea–choline chloride subsystems can be used to model the bulk properties of solvents with the deep eutectics of other component compositions.