Patent ID: 8802902

Claim:
A process for producing ethanol, comprising the steps of: hydrogenating acetic acid from an acetic acid feed stream in a reactor to form a crude ethanol product comprising ethanol, ethyl acetate, acetic acid, and water; separating at least a portion of the crude ethanol product in a first column at a first pressure into a first distillate comprising ethanol, ethyl acetate, and low concentration of water, and a first residue comprising from 2.5 to 40 wt. % acetic acid, from 60 to 99 wt. % water, and less than 0.5 wt. % ethanol, and separating at least a portion of the first distillate in a second column at a second pressure to yield an ethanol product stream and an ethyl acetate stream; wherein the second pressure is higher than the first pressure and; wherein the first distillate is not dehydrated using an adsorption unit or membrane.