Patent ID: 8268159
Filing Date: 2012-09-18
Classification: C02F,C25B

Abstract:
1. A method for producing a sodium hypochlorite solution, comprising: (a) obtaining an electrolytic cell comprising a sodium ion conductive ceramic membrane configured to selectively transport sodium ions, the ceramic membrane separating an anolyte compartment configured with an anode and a catholyte compartment configured with a cathode; (b) providing an impure sodium chloride solution containing calcium, magnesium, or other precipitable cations in the anolyte compartment of the cell; (c) providing water and sodium ions in the catholyte compartment of the electrolytic cell; (d) applying an electric current to the electrolytic cell thereby: (e) withdrawing and transporting sodium hydroxide solution from the catholyte compartment to the anolyte compartment in a controlled fashion to produce sodium hypochlorite in the anolyte compartment according to the following reaction: HOCl+HCl+2NaOH→NaOCl+NaCl+2H (f) maintaining a pH of the impure sodium chloride solution within the anolyte compartment at a pH less than 8, wherein the pH of the impure sodium chloride solution within the anolyte compartment is also maintained at about 6 or greater; and (g) removing a solution comprising sodium hypochlorite from the anolyte compartment.