Electrolyticdialysis

• US 3,963,567 A
• Filed: 01/09/1975
• Issued: 06/15/1976
• Est. Priority Date: 01/09/1975
• Status: Expired due to Term

• Current Assignee: Marc Cole
• Original Assignee: Marc Cole
• Inventors: Cole, Marc
• Primary Examiner(s): Mack, John H.
• Assistant Examiner(s): Prescott, A. C.
• Application Number:
  US05/539,632
• Time in Patent Office: 523 Days
• Field of Search: 204/151, 204/180 P, 204/128, 204/129
• US Class Current: 205/621
• CPC Class Codes: B01D 2311/2603 Application of an electric field, different from the potential difference across the membrane
• CPC Class Codes: B01D 61/44 Ion-selective electrodialysis
• CPC Class Codes: C02F 1/4604 for desalination of seawater or brackish water
• CPC Class Codes: C02F 1/4693 electrodialysis
• CPC Class Codes: C02F 2201/46115 Electrolytic cell with membranes or diaphragms
• CPC Class Codes: C25B 1/46 in diaphragm cells
• CPC Class Codes: Y02A 20/124 Water desalination

Abstract

Sea water is deionized with simultaneous production of caustic soda, chlorine, and hydrogen by a novel electrodialysis process wherein sodium and chlorine ions are separated from said sea water, and said ions, while separated from each other, are electrically discharged.

Claims

1. The method for electrolytically dialyzing the solute of a solution of an electrolyte, said solution being contained in each cell of a group of functionally joined cells, each of said cells being provided with an ion-selective membrane, and each of said cells being compartmented by an ion-impervious dielectric membrane, which comprises subjecting the said solution to the action of a common direct electric field in such manner as to cause migration of ions of like charge of said solution thru said ion-selective membrane into a compartment of a neighboring cell whereas ions of opposite charge are sequestered by said ion-impervious membrane, allowing mutual electric discharge between the migrated and the sequestered groups of ions by electrically conductive means, recovering the resulting atoms, molecules, and reaction products of said atoms and molecules with the solvent of said solution, and also recovering a portion of the said solvent having a changed concentration of ions.

2. The method of claim 1 wherein the said ion-selective membrane is a cationic membrane.

3. The method of claim 1 wherein the solution of electrolyte is sea water.

4. The method of claim 3 wherein the recovered products are chlorine, caustic soda solution, hydrogen, and desalinated water.

5. The method of claim 1 wherein the said common direct electric field is produced by a pair of primary electrodes, one of the primary electrodes being positioned at each adjunct end of the said group of functionally joined cells, one of the said primary electrodes being in contact with the said electrolyte solution and the other primary electrode being in contact with the solvent of the said electrolyte solution, the said pair of primary electrodes being connected to a source of direct current voltage.

6. The method of claim 1 wherein the said electrically conductive means whereby mutual electric discharge of the said ions of opposite charge is effected are pairs of secondary electrodes, one of each of said pairs of secondary electrodes being positioned in each of the said compartments of the cells of claim 1, each of the pairs of secondary electrodes being connected by an electrically conducting wire.

7. The method of claim 1 wherein the electric circuit involved in production of said common direct electric field, and the circuit involved in said mutual electric discharge of the ions of opposite charge are both provided with current interrupters, the interruption of the current in the two said circuits being out-of-phase with each other.

8. The method of claim 1 wherein diffusion barriers are employed to protect the said ion-selective membranes from the corrosive action of products resulting from said method.

9. The method of claim 1 wherein spacer elements are employed to improve the efficiency of said method.

10. The method of claim 1 wherein the said ion-impervious membrane is composed of Teflon.

11. The method of claim 1 wherein the said solution of an electrolyte is brackish water.