Vapor-liquid-liquid equilibria of binary and ternary aqueous systems containing C6-hydrocarbons

Abstract

BackgroundTo develop process for separating water and C6-hydrocarbons, the vapor-liquid-liquid equilibrium (VLLE) data of the related mixtures are fundamentally important. MethodsThe isothermal vapor-liquid-liquid equilibrium (VLLE) data were measured for the binary and the ternary aqueous mixtures containing C6 hydrocarbons (benzene, n-hexane, and cyclohexane) at temperatures from 343 K to 383 K by using a modified static-type apparatus equipped with a visual cell. The VLLE data were correlated with the NRTL-HOC and the UNIQUAC-HOC models, respectively. Significant findingsIn addition to literature data, the experimental results of the binary systems reveal the temperature and molecular structure effects on the saturated compositions in three coexistent phases. The experimental ternary VLLE properties form a basis to verify the prediction by using the determined parameters of constituent binaries and also to modify the values of the binary parameters for improving the ternary VLLE calculations. The findings of this study offer new phase equilibria data for model development and process design for the related separation units.