Isobaric VLE of the mixture {1,8-cineole + ethanol}. EOS analysis and COSMO-RS modeling

Abstract The isobaric (vapor + liquid) equilibrium (VLE) at pressures of (33.33, 66.66 and 101.33) kPa is reported for the mixture {1,8-cineole (1,3,3-trimethyl-2-oxabicycle[2,2,2]octane) + ethanol} in the entire composition range. VLE data were correlated by means of three activity coefficient models (Wilson, NRTL and UNIQUAC) and they were found to be thermodynamically consistent. The mixture exhibits positive deviations from Raoult’s law. Peng–Robinson and SAFT equations of state (EOS) were used first to predict (interaction parameter, k ij , equal to zero), then to correlate (by adjusting the interaction parameter) the VLE. COSMO-RS model has been also used to predict VLE of the mixture. Both EOS and COSMO-RS model show deviations in the prediction of bubble points but reproduce quite well the dew points. COSMO-RS provides the best predictions.