Experimental and Modeling Investigation of Vapor–Liquid Equilibria and Excess Enthalpies in Binary Mixtures Containing γ-Valerolactone (GVL), Ethylbenzene, and Cyclohexene

High Resolution Image Download MS PowerPoint Slide In this work, the vapor–liquid equilibrium (VLE) and excess molar enthalpy ( H E ) of three binary mixtures, namely, ethylbenzene + γ-valerolactone (GVL), cyclohexene + GVL, and cyclohexene + ethylbenzene, were measured. VLE data were measured at 35.0 and 70.0 kPa for the GVL-containing mixtures and at 70.0 and 101.3 kPa for the ethylbenzene + cyclohexene mixture. Vapor pressures of the pure components were measured and correlated using an extended Antoine equation, which aligned well with the literature data. The H E values were experimentally determined at 298.15 K. All the binary mixtures exhibited positive H E, indicating endothermic mixing. Including H E data in the regression of binary interaction parameters (BIPs) was essential for accurate modeling; omitting these data led to inaccurate results, such as an incorrectly negative calculated H E . All three studied mixtures showed no azeotrope formation. Correlative models such as Wilson, NRTL, and UNIQUAC accurately represented the experimental VLE and H E data. In contrast, predictive group-contribution models UNIFAC and UNIFAC-Dortmund did not adequately reproduce the VLE and H E of the GVL-containing mixtures, mainly due to insufficient group parameters for GVL’s structure. COSMO-RS predictions improved when experimental vapor pressure data were included in compound properties. The VLE data were confirmed to be thermodynamically consistent upon verification using the Van Ness and L – W tests.