Dra. Susana BOTTINI
Investigadora Independientge CONICET
Prof. Titular DE, Dpto. Ing. Qca., Univ. Nacional del Sur
Planta Piloto de Ing. Qca., PLAPIQUI (UNS-CONICET)
Bahía Blanca, ARGENTINA
ABSTRACT: Knowledge on the phase behavior of multicomponent mixtures is required for process design and optimization. This information is particularly important in high-pressure processes, where changes in density and solubility and multiphase behavior may lead to complex phase scenarios. On the other hand, differences in polarity and the presence of associating molecules play a fundamental role in the fluid phase behavior of asymmetric mixtures. The need is for both, experimental data and thermodynamic models.Group-contribution methods represent a useful tool to predict thermodynamic properties of multicomponent systems. In principle, only a limited number of functional groups are required to represent an unlimited number of organic compounds and mixtures. In this paper, group-contribution models are applied to represent phase equilibria in size- and energy- asymmetric systems, including associating species. Examples are given for mixtures containing natural products, ionic liquids and high-pressure gases. The integration of predictive thermodynamic models to simulation and optimization routines and the application of phase equilibrium engineering tools facilitate the analysis of chemical processes. In the paper examples of separation and reaction problems are presented and discussed.