Measurement and prediction of high‐pressure phase equilibria with a dilute component in the gas phase: The methane‐n‐hexane system

Abstract

The design of vapor recovery processes requires very accurate vaporliquid equilibria data. In this work the problem is attacked from both an experimental and a correlational viewpoint, and the methane-n-hexane system is chosen for study. A predictive model for vapor-liquid equilibrium aids in the interpretation of the experimental measurements, and data acquired in this study agree closely with the theoretical predictions. Maximum deviation between calculated and experimental equilibrium ratios (yi/xi) is 8.5y0 with average absolute deviations of 3y0 for n-hexane and 0.1% for methane. Several procedures are described for checking the accuracy of experimental VLE data when a heavy vapor is present at low concentrations in the gas phase. Several potential sources of experimental error are also identified and discussed.

Vapor-liquid equilibria for the methane-acetone and ethylene-acetone systems at 25 and 50.degree.C

“…The results are shown in Table IV. For comparison, the results obtained from the data of Shim and Kohn (1) and Gunn et al ( 2) are shown In the same (2). It was found that the experimental data and the calculated results agree well with each other.…”

“…To evaluate the validity of the experimental procedure, the consistency test of Gunn et al (2) was applied to the data of the methane-n -hexane system. In this test, a vapor-phase mole fraction was calculated from T-P-x data by using the vlrlal equation of state truncated after the second virial coefficient.…”

V.l.e. measurements at high pressures and high temperatures on (methane+ -hexane)

“…Of these, the most recent are the works of Shim and Konh, (8) Poston and McKetta, (9) Gun et al, (10) Lin et al (11) and Chylinski et al (6) To compare the data of this study with other investigations, the reports by Shim and Konh (8) and Chylinski et al (6) were chosen as they are the only ones that include data collected at the same temperature and over a similar range of pressures to those obtained in this work. Furthermore, the comparison with Chylinski et al (6) also offers the opportunity to examine the reproducibility of the data, as both sets of data were obtained in the same v.l.e.…”

Vapor–Liquid Equilibria of Mixtures of Molecular Fluids Using the Activity Fraction Expanded Ensemble Simulation Method

“…Additionally, the components of this mixture also show significant size asymmetry which introduces challenges in the investigation of such mixtures (as discussed later) in the grand canonical ensemble. Extensive experiments − as well as equation-of-state calculations − have been performed for this mixture, and a large amount of data is available for comparison with molecular simulation results. Industrially, the study of this mixture is important for processes which entail the separation of propane, butane, and natural gasoline from natural gases and, hence, require very accurate predictions of VLE data.…”

“…Extensive experiments − as well as equation-of-state calculations − have been performed for this mixture, and a large amount of data is available for comparison with molecular simulation results. Industrially, the study of this mixture is important for processes which entail the separation of propane, butane, and natural gasoline from natural gases and, hence, require very accurate predictions of VLE data.…”