The three-parameter cubic equation of state with one parameter temperature-dependent (3P1T), P = RT/(V - b) - a(T)/[V(V + c) + b(3V + c)], recently developed for asymmetric mixture density calculations for nonpolar substances (Yu and Lu, 1987), has been applied to VLE calculations. The binary interaction parameter k12 obtained from the conventional random VDW mixing rule for the mixture parameter a has been used for the prediction of volumes of saturated liquid (Vℓ) and saturated vapor (Vν) at the conditions of the VLE data. The 3P1T equation is as capable for VLE calculations as the Soave-Redlich-Kwong, the Peng-Robinson, the Schmidt-Wenzel and the translated Peng-Robinson equations, but it yields lower Vℓ deviations than these equations. The improvement is more evident for highly asymmetric mixtures. The suitability of the form of the equation for representing Vℓ of nonpolar compounds over a wide range of molecular weight is further demonstrated.
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