Electrodialysis of solutions of tartaric acid and its salts

Electrodialysis with ion-exchange membranes is an effective method for the separation and concentration of food acids, and it has considerable capabilities as a step of their manufacture in both microbiological and chemical syntheses. A barrier effect and a facilitated electromigration effect in the electrodialysis of solutions of tartaric acid and its salts has been revealed. The dependence of the flux of hydrotartrate ions on current density is characterized by the occurrence of a plateau in the region of the barrier effect with the subsequent increase in mass transfer in the region of the facilitated electromigration effect. The found regularities of electrical mass transfer should be taken into account in the optimization of the separation, recovery, and concentration of food acids whose anions are organic ampholytes capable of charge exchange upon changing the pH at the membrane/solution interface.