The choice of solvent determines which of the two components in the original feed is removed predominantly in the distillation. For example, if the fresh feed to the distillation is a mixture of 83 mole% ethanol and 17 mole% water, and ethylene glycol is increased more than that of water. Therefore, ethanol is removed as the distillate from the extractive distillation column, and water is separated in the solvent recovery column. Fig. Extractive Distillation An alternative to recover ethanol is to use extractive distillation. The solvent used is Propylene Glycol. Recall also that ethanol forms a minimum-boiling azeotrope with water at approximately 89.4 mole% (96 wt %) ethanol. A process schematic for the process is shown in Fig. For this separation, propylene glycol meets all the requirements of an ideal extractive solvent a) It is miscible with water at all concentrations. distillate and the bottoms product, phenol, is recycled back to the first column. Fig. shows process flow sheet for separation of toluene and isooctane using phenol as the solvent.