Phase equilibria on binary systems containing diethyl sulfide

Isothermal vapor–liquid equilibrium (VLE) of the following systems was measured with a recirculation still: diethyl sulfide+ethanol at 343.15K, diethyl sulfide+1-propanol at 358.15K, and diethyl sulfide+propyl acetate at 363.15K. Diethyl sulfide+ethanol at 343.15K and diethyl sulfide+1-propanol at 358.15K systems exhibit positive deviation from Raoult's law, whereas diethyl sulfide+propyl acetate at 363.15K system exhibits only slight positive deviation from Raoult's law. A maximum pressure azeotrope was found in the systems diethyl sulfide+ethanol (x1=0.372, P=88.4kPa, T=343.15K) and diethyl sulfide+1-propanol (x1=0.640, P=96.8kPa, T=358.15K). No azeotropic behavior was found in diethyl sulfide+propyl acetate system at 363.15K. The experimental results were correlated with the Wilson model and compared to COSMO-SAC predictive model. Liquid and vapor phase compositions were determined with gas chromatography. All measured data sets passed the thermodynamic consistency tests. The activity coefficients at infinite dilution are also presented.