Solid–fluid phase equilibrium modeling for binary systems containing carbon dioxide

Abstract

The excess function formalism was used to represent the solid–fluid equilibrium of binary systems formed by carbon dioxide and heavy hydrocarbons. The model is based on the Peng–Robinson equation of state, extended to represent the PVT properties of pure components, and the Péneloux excess function formalism to represent the solid–fluid equilibrium properties of mixtures. The results show that the effect of density on the excess term should be taken into consideration in the calculations for CO 2/heavy hydrocarbons systems. This effect is particularly important in the vicinity of the gas critical point.