Patent ID: 7241918

Claim:
An adsorptive separation process comprising contacting a fermentation broth containing at least citric acid and gluconic acid, with a water-insoluble basic anionic exchange resin selected from the group consisting of a strongly basic anionic exchange resin possessing quaternary amine functional groups and having a cross-linked, copolymeric styrene or acrylic resin matrix, and a weakly basic anionic exchange resin possessing tertiary amine or pyridine functional groups and having cross-linked acrylic or styrene resin matrix, wherein the water-insoluble basic anionic exchange resin is in the sulfate form, at adsorption conditions selected to selectively adsorb said citric acid, said adsorption conditions including pH lower than the first ionization constant (pKa 1 ) of citric acid, and desorbing the citric acid with a desorbent comprising water or a dilute inorganic acid at desorption conditions.