Electrodialytic Water Splitting: Conversion of Dilute Sodium Acetate or Acetic Acid into Concentrated Acid

Abstract

Electrodialytic water splitting is an energy‐efficient and inexpensive means to produce relatively concentrated solutions of weak acids and bases from feed solutions of the corresponding salts. With contaminated feedstreams, ultrafiltration is a necessary prerequisite. A 6% solution of sodium acetate was readily resolved into 35% acetic acid and about 8% sodium hydroxide. The degree of concentration achieved is determined by the electro‐osmotic coefficients of the ions involved. This process can also serve to concentrate relatively dilute solutions of weak acids and weak bases, ones too weak to be capable of concentration by direct electrodialysis. The water splitting process has unusual advantages for the treatment of the products of fermentation in closed‐loop systems.