Wastefree purification method for potassium brine used in industrial electrochemical processes

A new concept is presented for purifying potassium brine (KCl solution) obtained from technical-grade potassium chloride. This concept is based on the hydroxide/carbonate method of removing ions of alkaline earth metals and on separating SO₄^2- ions by means of zirconyl anion exchanger. The purification process provides the following products: purified potassium brine suitable for the manufacture of KClO₃ or for further purification and subsequent manufacture of KOH, Cl₂ and H₂ using membrane cell technology, magnesium and potassium containing agricultural lime (chalk) suitable for neutralizing soil acidity and enriching soil with magnesium and potassium, and technical-grade potassium sulphate containing 99.0 to 99.8% K₂SO₄.