Separation of lactic acid from fermentation broth with an anionic polymeric absorbent

摘要

Lactic acid is separated from a fermentation broth by using an adsorbent comprising a water-insoluble macroreticular or gel weakly basic anionic exchange resin possessing tertiary amine or pyridine functional groups or a strongly basic anionic exchange resin possessing quaternary amine fuctional groups. The resins are in sulfate form and have a cross-linked acrylic or styrene resin matrix. Lactic acid is desorbed with water or dilute inorganic acid, e.g., sulfuric. The pH of the feed is maintained below the ionization constant (pKa) of lactic acid to obtain high selectivity.