Phase equilibria of binary systems of 3-methylthiophene with four different hydrocarbons

Isothermal vapor–liquid equilibrium (VLE) for systems 3-methylthiophene + 2-methylpentane at 333.15 K, 3-methylthiophene + n-hexane at 333.15 K, 3-methylthiophene + methylcyclopentane at 343.15 K, and 3-methylthiophene + methylcyclohexane at 373.15 K were measured with a recirculation still. All systems exhibit positive deviation from Raoultʹs law. No azeotropic behavior was found in any of the systems at the measured temperatures. The experimental results were correlated with the Wilson model and also compared with the original UNIFAC and UNIFAC-Dortmund predictive models. 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). The activity coefficients at infinite dilution are also presented.