Prediction of Finite Concentration Behavior from Infinite Dilution Equilibrium Data

The principle aim of this project is to show if it is possible to use the activities coefficients at infinite dilution to find the parameters of different models. It was suggested two modern methods for calculating the activities coefficients at infinite dilution (γ∞), MOSCED method (modified separation of cohesive energy density) and SPACE method (Solvatochromic Parameters for Activity Coefficient Estimation). The two equations are applied to 18 systems and SPACE equation gives better results than MOSCED equation.This project presents the evaluation of the uses of activities coefficients at infinite dilution, γ∞, to calculate the parameters of different equations: Wilson,NRTL and UNIQUAC. One of the uses is azeotropic calculation where it is applied for 10 different binary systems from the experimental γ and the results when compared with the experimental data for azeotrope at the same temperature show as nearly as good if using the actual parameters of the equations. The other use is the calculation of Vapor Liquid Equilibrium data where it applied for 13 different binary systems (194 points) from the experimental γ∞  and the results also show as high accuracy as if using the actual parameters of the equations. From these calculations UNIQUAC equation gives the highest accuracy than the other equations.