Thermophysical properties of choline chloride/urea deep eutectic solvent in aqueous solution at infinite dilution at T=293.15-323.15 K

The green solvents called deep eutectic solvents (DESs) have been investigated in numerous technologies in the recent years. In this study, for the first time it was attempted to measure thermophysical properties of commonly used DES (choline chloride/urea) in aqueous solutions at dilution concentration ranges of DES (x(1) = 0.0000-0.0182) mole fraction and at T = 293.15-323.15 K. Some of the properties including density, speed of sound, refractive index and viscosity were measured for calculation of some thermophysical properties including standard partial molar volume (V phi 0\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$V_{{\upvarphi }}<^>{0}$$\end{document}), partial molar isentropic compressibility (kappa phi 0\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\kappa_{{\upvarphi }}<^>{0}$$\end{document}), excess molar volume (V-E), viscosity B-coefficient and molar refraction (R-D) in dilute region of concentration. The obtained values of above-mentioned properties were used for evaluation of the solute-solvent interaction of the studied binary mixtures (DES + water).