Vapor-liquid equilibria of isopropyl alcohol plus 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 salvation 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 SRI( to approach the experimental data are much greater than for CPA. (C) 2013 Elsevier B.V. All rights reserved

Derivative properties from high-precision equations of state

In this study, the behavior of derivative properties estimated by equations of state, including isochoric heat capacity, isobaric heat capacity, speed of sound, and the Joule–Thomson coefficient for pure compounds and a mixture, has been investigated. The Schmidt–Wagner and Jacobsen–Stewart equations of state were used for predictions of derivative properties of 10 different pure compounds from various nonpolar hydrocarbons, nonpolar cyclic hydrocarbons, polar compounds, and refrigerants. The estimations were compared to experimental data. To evaluate the behavior of mixtures, the extended corresponding states principle (ECS) was studied. Analytical relationships were derived for isochoric heat capacity, isobaric heat capacity, the Joule–Thomson coefficient, and the speed of sound. The ECS calculations were compared to the reference surface data of methane + ethane. The ECS principle was found to generate data of high qualit