Collect. Czech. Chem. Commun. 1992, 57, 16-25

Ternary Corrections in the Liquid-Liquid Equilibria for Four-Component System Heptane-Toluene-N-Methylpyrrolidone-Ethylene Glycol

Elena Graczová and Július Surový

Department of Chemical and Biochemical Engineering, Slovak Technical University, 812 37 Bratislava


Prediction for four-component liquid-liquid equilibrium is based on binary a ternary equilibrium data. Three-parameter equations for the excess Gibbs energy (NRTL equation, Redlich-Kister 4th order expansion and Wilson equation in Novák modification) extended by universal ternary contribution were employed for a thermodynamic description of the four-component system. The computation method was applied for a model four-component system heptane-toluene-N-methylpyrrolidone-ethylene glycol, t = 50 °C. The computed equilibrium data were compared with experimental ones measured for the weight ratio of the mixture N-methylpyrrolidone per ethylene glycol 20/80, 40/60 and 60/40.