Selective Pertraction of Carboxylic Acids Obtained by Citric Fermentation

Abstract

Pertraction through liquid membranes is one of the most recent liquid–liquid extraction techniques that could be applied for separation of biosynthetic products. This article describes facilitated pertraction has been used for selective separation of citric, malic, and succinic acids from a mixture. The separation equipment included a U‐shaped cell containing 1,2‐dichloroethane as a liquid membrane and Amberlite LA‐2 as a carrier. The experimental data indicated that malic and succinic acids can be initially selectively separated from citric acid at an equimolecular ratio between the carrier and these acids. Then, for a selective separation of malic acid from succinic acid, a carrier molar concentration inside the liquid membrane equal to that of malic acid in the feed phase was required. The favorable effect of carrier concentration on separation selectivity was enhanced by the modification of aqueous phases pH and mixing intensification.

Keywords:

• Facilitated pertraction
• Liquid membrane
• Citric acid; Malic acid
• Succinic acid
• Amberlite LA‐2
• Mass flow
• Permeability factor
• Selectivity factor