abstract |
Recovery of ethanol from a crude ethanol product obtained from the hydrogenation of acetic acid using an extractive distillation column. A diluted acid stream, comprising less than 30 wt. % acetic acid, is used as the extractive agent and is fed at a point above the crude feed stream. The column yields a residue that comprises ethanol, acetic acid, and water. The diluted acid stream may be separated from the residue and returned to the extractive distillation column. |