Electrolytic process for potassium hydroxide

Abstract

Improved current efficiency is obtained in an electrolytic membrane cell for the production of potassium hydroxide by employing in combination: (a) a membrane comprised of a carboxylic acid substituted polymer prepared by reacting a fluorinated olefin with a comonomer having a functional group selected from the group consisting of carboxylic acid and a functional group which can be converted to carboxylic acid; (b) a potassium chloride brine feed through the anolyte chamber of the cell having a concentration in the range from about 250 to about 300 grams of potassium chloride per liter; (c) a cell operating temperature in the range from about 90.degree. to about 100.degree. C.; (d) producing a depleted brine in the anolyte chamber after electrolysis in which the potassium chloride consumed by electrolysis ranges from about 5 to about 15 percent by weight of the potassium chloride originally present in the brine feed, and (e) maintaining a catholyte potassium hydroxide concentration in the range from about 500 to about 600 grams potassium hydroxide per liter.

Dependencies are inferred from the claim text.