A generalized reference state at constant volume for the prediction of phase equilibria from low pressure model parameters: Application to size-asymmetric systems and to the Wong-Sandler mixing rule

作者：Neau Evelyne^*; Escandell Joan; Raspo Isabelle

来源：Chemical Engineering Science, 2011, 66(18): 4148-4156.

DOI：10.1016/j.ces.2011.05.043

• Reference state
• Cubic equation of state
• Excess Gibbs energy models
• Wong-Sandler mixing rule
• Size-asymmetric systems
• Vapor-liquid equilibria

This paper describes an EoS/G(E) approach based on cubic equations of state making reference to low pressure G(E) models derived from the lattice fluid theory of Guggenheim. The proposed method does not present the theoretical problems encountered with the literature reference states (infinite pressure of Huron-Vidal, zero pressure of Michelsen and constant packing fraction of Peneloux), namely the description of the alpha function with combinatorial terms derived from both the excess Gibbs energy model and the EoS. The main advantage of the proposed method is to successfully account for the size-asymmetry of mixture components and to improve the results obtained with the Wong-Sandler mixing rule. Comparisons are performed with the MHV1, LCVM and the original Wong-Sandler approach at infinite pressure.

• 出版日期2011-9-15