Comparer des méthodes

	UNIFAC	Équation d'état de Peng-Robinson
Domaine	Physique appliquée	Physique appliquée
Famille	Process / pipeline	Process / pipeline
Année d'origine	1975	1976
Auteur d'origine	Aage Fredenslund, Russell Jones, John Prausnitz	Ding-Yu Peng and David Bernard Robinson
Type	Activity coefficient model; predictive liquid-phase property method	Equation of state; thermodynamic property correlation
Source fondatrice	Fredenslund, A., Jones, R. L., & Prausnitz, J. M. (1975). Group-contribution estimation of activity coefficients in nonideal liquid mixtures. AIChE Journal, 21(6), 1086-1099.	Peng, D. Y., & Robinson, D. B. (1976). A new two-constant equation of state. Industrial & Engineering Chemistry Fundamentals, 15(1), 59-64.
Alias	UNIFAC predictive model, UNIQUAC functional-group contribution	PR-EOS, Peng-Robinson model
Apparentées	3	4
Résumé	UNIFAC (Universal Functional-group Activity Coefficient) is a predictive model for liquid-phase activity coefficients of multicomponent mixtures. Developed by Fredenslund, Jones, and Prausnitz in 1975, it decomposes molecules into functional groups and uses group interaction parameters to estimate non-ideal behavior. UNIFAC is revolutionary because it can predict phase equilibria for mixtures never experimentally measured, making it invaluable for process design and chemical engineering.	The Peng-Robinson equation of state is a cubic model that describes the thermodynamic properties of pure fluids and mixtures. Introduced by Ding-Yu Peng and David Bernard Robinson in 1976, it improves upon earlier models (van der Waals, Redlich-Kwong) by better predicting compressibility factors and phase equilibria, especially near the critical point. It is widely used in petroleum engineering, chemical process design, and natural gas calculations.