Patent ID: 8829249

Claim:
A method of producing ethanol comprising: esterifying acetic acid and ethanol in a first reaction zone to produce an esterification product comprising ethyl acetate, ethanol, water, and acetic acid; separating at least a portion of the esterification product in a first column to yield a first distillate comprising ethyl acetate, ethanol, and water; biphasically separating at least a portion of the first distillate in a decanter into an organic phase comprising ethyl acetate and an aqueous phase comprising ethanol and water; reacting at least a portion of the organic phase with hydrogen in a second reaction zone to produce a crude reaction mixture; separating at least a portion of the crude reaction mixture in a second distillation column to yield a second distillate comprising ethyl acetate and ethanol, and a second residue comprising ethanol; and returning at least a portion of the second distillate to the first reaction zone.