Patent ID: 8877987

Claim:
A process for producing ethanol, the process comprising the steps of: hydrogenating acetic acid in the reactor in the presence of a catalyst to form a crude ethanol product; separating at least a portion of the crude ethanol product in a first distillation column to yield a first distillate comprising ethanol, ethyl acetate, and water, and a first residue comprising acetic acid; separating at least a portion of the first distillate in a second distillation column to yield a second distillate comprising ethyl acetate and a second residue comprising ethanol and water, wherein the second distillation column is an extractive distillation; and dehydrating at least a portion of the second residue via extractive distillation to yield an anhydrous ethanol composition comprising less than 1 wt. % water; wherein a first extractive agent is used to extract ethanol or water from the second residue; a second extractive agent comprising water is fed to the second distillation column; and wherein the first extractive agent is different than the second extractive agent.