A recently derived equation of state (EoS) for the dense fluids (both compressed liquids ( T T c ) and dense supercritical fluids ( T T c )) based on the thermodynamic perturbation theory has been extended to the mixture of dense fluid. Based on this EoS, which is called “linear Yukawa isotherm regularity (LYIR)”, the quantity of Z ? Z CS varies linearly with , in which Z = pv / RT is the compression factor, ? =1/ v is the molar density and Z cs is Carnahan?Starling expression with temperature?dependent hard?core diameter for mixture . The LYIR EoS was extended to the mixture of dense fluids in the framework of van der Waals’s one?fluid approximation in the present work. To assess the ability of the extended?LYIR EoS to predict and/or reproduce the thermodynamic properties of liquid mixtures, a comparison with the literature experimental data was done for different types of dense subcritical binary mixtures, at the wide range of temperature and composition. A wide comparison between the extended?model?predicted data and the corresponding experimental data for different kinds of dense fluids’ mixture showed that the extended?model is of the reasonable capability for reproducing/correlating of the thermodynamic properties of the mixtures. Using the mixing rules, the composition dependences of the parameters of the extended-LYIR EoS were investigated and considered to be as quadratic functions of mole fraction. The temperature?dependence of the two parameters of the extended?LYIR EoS was investigated and an explicit model was then proposed to mimic of their behaviors. The density calculation by making use of the model parameters showed a maximum deviation which is less than 1% for density. Moreover, the values of effective attractive range and effective molecular diameter between two constituents of mixture were estimated and reported in this work.
