Recovery of natural organic fruit acids, especially oxalic acid from mixture with malic and citric acids

摘要

Dilute juice is electrodialyzed in four chambers, formed by alternating cationic and anionic exchange membranes, located between anode and cathode. Flow to each chamber is recirculated, with appropriate make-up (5, 6, 11, 12) and off take (7, 8, 9, 10) connections as follows. The anode side chamber (K1) contains fruit acid concentrate with distilled water addition at the inlet; concentrated fruit acid is removed, from which further recovery of fruit acids takes place in conventional manner.