EXTRACTION OF SHIKIMIC AND QUINIC ACIDS

Solvent extraction using an extractant/diluent system was evaluated for the recovery of shikimic and quinic acids. Tridodecylamine (TDA) was used as the extractant, and 1-heptanol as the diluent. TDA complexes with the acid resulting in an acid-amine complex, which is solvated by the alcohol diluent. In back extraction, oleic acid was added to the organic phase as a displacer. Oleic acid competitively displaces the carboxylic acid in the acid-amine complex, thus forming a displacer-amine complex. The distribution coefficient for back extraction by competitive displacement increased by at least an order of magnitude depending on the mole to mole ratio of oleic acid to TDA

Based on results from batch extraction experiments, a mass-action analysis was introduced for modeling forward and back extraction. The mass-action analysis served as a tool for understanding the mechanism of the extraction process.