Thermodynamic Properties of Aqueous Lithium Bromide Using a Multiproperty Free Energy Correlation

Abstract

A new correlation of the thermodynamic properties of aqueous lithium bromide was constructed based on a Gibbs free energy fundamental function. The coefficients of the function were calculated using a multiproperty curve fit to vapor pressure, specific heat, and volumetric data. The specific heat data used are new experimental values obtained in our laboratory and described in a companion paper. The vapor pressure and volume data used came from the literature. The correlation gives good accuracy over the full range of liquid concentration from pure water up to the crystallization line and from 5°C to 250°C. This expanded range of applicability is expected to be useful in the next generation of high-temperature absorption cycles. The fundamental function approach used allows simple computation of thermodynamically consistent properties including vapor pressure, specific heat, specific volume, enthalpy, entropy, differential heat of dilution, and chemical potential of the components, among others. The details of the correlation are presented; software that implements the correlation is available in several formats.