Gibbs free energy minimization for the calculation of chemical and phase equilibrium using linear programming

One important concern in the calculation of chemical and phase equilibrium using Gibbs free energy minimization is how to guarantee finding the global optimum without depending on an initial guess. This work proposes an approach for the minimization of the Gibbs free energy using linear programming that guaran tees finding the global optimum within some level of precision, for any kind of thermodynamic model. The strategy was used in the calculation of chemical and phase equilibrium involving binary and ternary systems at low and high pressure. The method presented in this proposal is easy to implement, robust and can use several thermodynamic models. (C) 2009 Elsevier B.V. All rights reserved.