Vapor–liquid equilibria of isopropyl alcohol + propylene at high pressures: Experimental measurement and modeling with the CPA EoS

The high pressure vapor–liquid equilibria of binary mixtures of propylene and isopropyl alcohol were measured experimentally within a temperature range of 315–440 K and pressures up to 6 MPa, using a synthetic method. The experimental data were modeled using the cubic plus association (CPA) equation of state (EoS) by once considering and once not considering solvation between the inert and polar molecules in the mixture. Results indicated that taking solvation into account did not make a huge improvement in the accuracy of CPA for this particular system. In addition, the Soave–Redlich–Kwong (SRK) EoS, representing the widely-used engineering EoS family, was also compared to the CPA. Results showed that both the CPA and SRK perform well for this system in the pressure and temperature range investigated, however, the values of binary interaction coefficients required by SRK to approach the experimental data are much greater than for CPA.