Transport properties of pure and mixture of ionic liquids from new rough hard-sphere-based model

Abstract

This paper aims to develop a new semi-theoretical model based on the rough hard-sphere (RHS) theory to correlate and predict the transport properties of 17 ionic liquids (ILs). The proposed model comprises smooth hard-sphere taken from modified Enskog's theory and a coupling parameter of translational and rotational motions. The molecular scaling constants to be used in the new RHS model were taken from previously developed perturbed hard-sphere equation of state for ILs. The performance of model has been checked over the temperature range within 263–388 K and pressures up to 249.6 MPa. From 1195 experimental data points examined, the AARD of correlated and predicted dynamic viscosities was found to be 3.67%. In the case of thermal conductivities, the proposed model correlated and predicted 130 experimental data points with AARD equal to 2.15%. The comparison of the new RHS-based model with the previous RHS model and group-contribution method demonstrated the superiority of the present work over the literature ones. The proposed RHS-based model has also been extended to14 binary mixtures formed by IL + IL and IL + molecular solvent. From 736 data points examined for the mentioned mixtures, the AARD of predicted viscosities was found to be 5.08%.