Liquid-vapour critical region of the most volatile component of the ternary system. II. Data reduction

Abstract

Wichterle, I. and Uchytil, P., 1984. Liquid-vapour critical region of the most volatile component of the ternary system. II. Data reduction. Fluid Phase Equilibria, 16: 117–126. A correlation of binary vapour-liquid equilibrium data at conditions around the critical point of the more volatile component was proposed. The fractional function with three adjustable parameters was used to express the dependence of K-value on pressure or composition. This function secures the boundary conditions ensuing from the existence of critical point. By introducing hypothetical states (vapour pressure above or critical pressure below the critical temperature), the proposed function is continuous regardless of temperature. The experimental data on vapour-liquid equilibria in the ethane - propane and ethane - - n-butane systems were reduced using the model presented. The necessary analytical description of ternary (including binary) critical locus was achieved via a simple function.