Patent ID: 9156754
Filing Date: 2015-10-13
Classification: C07C,C10L

Abstract:
1. A process for producing ethanol comprising: hydrogenating acetic acid and/or an ester thereof in a reactor in the presence of a catalyst to form a crude ethanol product; separating a portion of the crude ethanol product in a first extractive distillation column to yield a first distillate comprising acetaldehyde and ethyl acetate, and a first residue comprising ethanol, and water; separating a portion of the first residue in a second distillation column to yield a second residue comprising water and a vapor overhead comprising ethanol and water; removing water from a portion of the vapor overhead to yield an ethanol mixture stream; and separating at least a portion of the ethanol mixture stream in a third distillation column to yield a third distillate comprising 70 to 90 wt. % ethanol and a third residue comprising ethanol and less than 8 wt. % water; wherein the third distillate is fed to the first column and at least a portion of the first distillate is returned to the reactor.