Three-phase, liquid-liquid-gas (LLG) equilibrium behavior was studied for the ternary system trans-decalin-n-decane-CO2. A stoichiometric technique was used to obtain equilibrium phase compositions and molar volumes over a range of temperatures and pressures from the critical point of CO2 to the tricritical point of the ternary mixture. The Peng-Robinson equation of state was found to describe the pressure-temperature (PT) projection of the LLG equilibrium region for this ternary mixture with quantitative accuracy, and provides a reasonable fit of phase compositions and molar volumes. The effects of scaling near mixture critical points and inadequate mixing rules are shown to be the primary limitations to more accurate descriptions of multiphase equilibria.
ASJC Scopus subject areas
- Chemical Engineering(all)
- Physics and Astronomy(all)
- Physical and Theoretical Chemistry