Multiphase coexistence for mixtures containing water, 2-propanol, and ethyl acetate

Isothermal vapor–liquid equilibrium (VLE) data were measured for ethyl acetate+2-propanol at temperatures from 333.15 to 373.15 K, while isothermal vapor–liquid–liquid equilibrium (VLLE) data were determined experimentally for ethyl acetate+water and water+2-propanol+ethyl acetate at temperatures from 308.15 to 348.15 K. A maximum pressure azeotrope exhibits on each isotherm of ethyl acetate+2-propanol. The NRTL and the UNIQUAC models with ideal gas phase assumption well represent the VLLE properties for binary ethyl acetate+water, when the model parameters are treated as a linear function of temperature. With the parameters determined from the phase equilibrium data of the constituent binaries, the UNIQUAC model predicted qualitatively the binodal curves for ternary water+2-propanol+ethyl acetate, but failed in the region near the plait point. By adjusting six parameters simultaneously, the NRTL and the UNIQUAC models correlated the binodal locus to within reasonable accuracy, and the UNIQUAC model calculated the vapor compositions and equilibrium pressures satisfactorily.