  For the design and optimization of CO2 recovery from alcoholic fermentation
processes by distillation, models for vapor-liquid equilibria (VLE) are needed.
Two such thermodynamic models, the Peng-Robinson equation of state (EOS) and a
model based on Henry's law constants, are proposed for the ternary mixture
N2+O2+CO2. Pure substance parameters of the Peng-Robinson EOS are taken from
the literature, whereas the binary parameters of the Van der Waals one-fluid
mixing rule are adjusted to experimental binary VLE data. The Peng-Robinson EOS
describes both binary and ternary experimental data well, except at high
pressures approaching the critical region. A molecular model is validated by
simulation using binary and ternary experimental VLE data. On the basis of this
model, the Henry's law constants of N2 and O2 in CO2 are predicted by molecular
simulation. An easy-to-use thermodynamic model, based on those Henry's law
constants, is developed to reliably describe the VLE in the CO2-rich region.
