Estimations of the viscosities of binary mixtures with different equations of state and mixing rules

Abstract

In this study, the Eyring's kinematic viscosity model was applied with the consideration that the activation free energy of flow was related to the excess free energy of mixtures and estimated with the equation of state (EOS). The effects of the equation of state, mixing rule, and interaction parameter on the viscosity estimations were considered. The results of estimations obtained with three two-parameter EOS, Redlich–Kwong (RK), Soave–Redlich–Kwong (SRK), and Peng–Robinson (PR), and four three-parameter EOS, Patel–Teja (PT), Harmens–Knapp (HK), Iwai–Margerm–Lu (IML), and Schmidt–Wenzel (SW), were compared with the experimental data reported in literature. It is observed that among these EOS only the PT, HK, and SW EOS of three-parameter and the two-parameter EOS of Peng–Robinson can successfully estimate these viscosities. It is observed that the molecular interaction parameter dominantly affects the estimation results. The estimations with the interaction parameters correlated from the densities of mixtures are better than those obtained from the excess volumes. This is a different observation from our previous work where 65 binary mixtures consisting of nonpolar, polar, and acidic compounds, and water were correlated with the same EOS and mixing rules applied here. The average absolute relative deviations and the binary interaction parameters of the successful estimations are given in two tables for reference. The details of the estimations are discussed.