A Review on Global Optimization Methods for Phase Equilibrium Modeling and Calculations

The phase equilibrium modeling for multi-component systems is essential in process systems engineering. In particular, phase stability analysis, Gibbs free energy minimization and estimation of parameters in thermodynamic models are challenging global optimization problems involved in phase equilibrium calculations and modeling for both reactive and non-reactive systems. To date, many significant works have been performed in the area of global optimization, and several algorithms and computational contributions of global optimization have been used for solving these problems; global optimization methods used include both deterministic and stochastic algorithms. To the best of our knowledge, there is no review in the literature that focuses on the global optimization methods and their applications to phase equilibrium modeling and calculations. In this paper, we briefly describe selected deterministic and stochastic optimization algorithms, and then review their use for phase stability analysis, Gibbs free energy minimization and parameter estimation in phase equilibrium models. In short, we provide a general overview of global optimization for modeling and calculating the phase behavior of systems with and without chemical reactions including the prediction of azeotropes and critical points.