Densities and Viscosities of (Fluoroalcohol+Water) Systems under High Pressures

Abstract

The densities and the viscosities of the binary mixtures of water with 2, 2, 2-trifluoroethanol, 2, 2, 3, 3-tetrafluoropropanol, and 2, 2, 3, 3, 3-pentafluoropropanol have been measured using a vibratingtube densitometer and a falling-body viscometer, respectively. The measurements were performed at temperatures ranging from 298 to 323K and at pressures up to 80MPa with the estimated uncertainties of ±0.1% for density and ±2% for viscosity.
The excess molar volumes, partial molar volumes, isothermal compressibilities of fluoroalcohol/water systems were determined based on the Tait equation smoothed against the composition with the simple polynomial equation. The temperature, pressure and composition dependences of these properties and those of the viscosities were investigated in comparison with the hydrocarbon-alcohol/water systems previously reported. Furthermore, the comparison between the present results and the spectroscopic data have been also undertaken.