Isothermal vapor-liquid equilibrium (VLE) for diethyl sulfide + cyclohexane were measured at 353.15 and 343.15 K and diethyl sulfide + 2-ethoxy-2-methylpropane were measured at 343.15 and 333.15 K with a circulation still. All systems exhibit slight positive deviation from ideality. No azeotropic behavior was found in any of the systems studied. The experimental results were correlated with the Wilson model with temperature dependent parameters and also compared with the original UNIFAC, and the COSMO-RS predictive models. The measured diethyl sulfide + cyclohexane VLE have been used simultaneously with the excess enthalpy from literature for a correlation of temperature-dependent Wilson parameters. Excess molar enthalpies at 298.15 K for diethyl sulfide + 2-ethoxy-2-methylpropane system were calculated from the VLE data. Analyses of liquid and vapor-phase composition were determined with gas chromatography. All VLE measurements passed the used thermodynamic consistency tests (integral, infinite dilution and point test). (c) 2007 Elsevier B.V. All rights reserved.