Viscosity calculations with the aid of an equation of state

摘要

The excess activation free energy of flow as defined in the Eyring model was calculated from the excess Gibbs free energy of mixture multiplied by a proportionality factor, in which the excess Gibbs free energy of mixture was estimated from the Patel-Teja equation of state with zero binary interaction constant. It was found that the proportionality factor could be treated as a constant for a nonaqueous system, whereas the factor was considered as a linear composition-dependent (LCD) function for an aqueous system (or a strongly hydrogen-bonded system). Promising results have been obtained from the proposed method to correlate viscosity data for a wide variety of nonaqueous and aqueous mixtures. These model parameters could be estimated from a limited knowledge of mixture viscosity data; one point for a nonaqueous system and two data points for an aqueous system. [References: 41]