Viscosities of Aqueous LiNO3 Solutions at Temperatures from 298 to 573 K and at Pressures up to 30 MPa

The viscosities of four (0.265, 0.493, 1.074, and 1.540 mol·kg-1) aqueous LiNO3 solutions were measured in the liquid phase with a capillary flow technique. Measurements were made at four isobars (0.1, 10, 20, and 30 MPa). The range of temperatures was from 298 to 573 K. The total uncertainties of viscosity, pressure, temperature, and concentration measurements were estimated to be less than 1.5%, 0.05%, 15 mK, and 0.014%, respectively. The reliability and accuracy of the experimental method was confirmed with measurements on pure water for five selected isobars (1, 10, 20, 40, and 50 MPa) and at temperatures between 294.5 and 597.6 K. The experimental and calculated values from the International Association for the Properties of Water and Steam formulation for the viscosity of pure water show excellent agreement within their experimental uncertainty (AAD = 0.27%). The temperature, pressure, and concentration dependences of the relative viscosity ((eta)/(eta)0, where (eta)0 is the viscosity of pure water) were studied. The behavior of the concentration dependence of the relative viscosity of aqueous LiNO3 solutions was discussed in light of the modern theory of transport phenomena in electrolyte solutions. The values of the viscosity A and B coefficients of the Jones-Dole equation for the relative viscosity ((eta)/(eta)0) of aqueous LiNO3 solutions as a function of temperature were studied. The derived values of the viscosity A and B coefficients were compared with the results predicted by the Falkenhagen-Dole theory of electrolyte solutions and calculated with the ionic B coefficient data. Different theoretical models for the viscosity of electrolyte solutions were stringently tested with new accurate measurements on LiNO3(aq). The predictive capability of the various models was studied. The measured values of the viscosity at atmospheric pressure were directly compared with the data reported in the literature by other authors.