Using a dilute acid stream as an extractive agent

摘要

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.

主权项

1. A process for producing ethanol, comprising:
hydrogenating acetic acid from an acetic acid feed stream in a reactor to form a crude ethanol product; separating at least a portion of the crude ethanol product in a first column into a first distillate comprising acetaldehyde and ethyl acetate, and a first residue comprising ethanol, ethyl acetate, water and acetic acid; introducing a dilute acid stream to the first column at a location above a feed point of the crude ethanol product; and recovering ethanol from the first residue.