Permeation Behavior of Organic Acids through a Membrane with Electrodialysis.

For electrodialysis of lactic and acetic acids, the effect of pH on the permeation behavior was examined. A strong basic or perfluoro anion exchange membrane was used. Even when the organic acids were undissociated, permeation of these acids was observed and the addition of HCl promoted the permeation rate. The permselectivity of lactic acid over acetic acid was large at low pH and decreased as the dissociation of acetic acid proceeded at high pH.