High-pressure multiphase behavior of the ternary systems (ethene + water + 1-propanol) and (ethene + water + 2-propanol): Part II: Modeling

Calculation results for the high-pressure liquid–liquid–vapor phase equilibrium of two ternary systems (ethene + water + 1-propanol) and (ethene + water + 2-propanol) are presented and compared with experimental data from the first part of this series of publications. The experimental data cover the temperature range from 293 K to 333 K at pressures up to 20 MPa. The calculation results are based on the Peng–Robinson equation of state (EoS) which was combined with various mixing rules (by van der Waals, by Panagiotopoulos and Reid, by Sandoval et al. as well as by three modifications of the mixing rule introduced by Huron and Vidal). The prediction results are based on parameters which were determined from binary mixture data. These predictions are in qualitative agreement with the experimental data (e.g., pattern and location of the high-pressure phase boundaries and existence of a liquid–liquid–vapor equilibrium). The extent of the two-phase and three-phase regions and the compositions of the coexisting phases depend strongly on the mixing rule. A good agreement between the experimental data and the calculation results was not achieved. However, a good agreement was achieved by adjusting the interaction parameters to the experimental high-pressure three-phase equilibrium data of the ternary systems instead.