US4295950A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Desalination with improved chlor-alkali production by electrolyticdialysis
Assignee: Individual
•
Filing: 1980-06-05
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Granted: 1981-10-20
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Expires: 2000-06-05
Abstract
Abstract An electrodialysis cell and process for desalination of aqueous brine with concomitant improved production of chlor-alkali, using a novel porous structure, the interconnected micro-pores of which are filled with an alkali metal amalgam, which may function as a cathode or as a cation permeable diaphragm, and using a saturated metal chloride aqueous solution as anolyte.
Inventors
- 👤 Marc Cole
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 07:24
CPC Classifications
B; B01; B01D; B01D61/00; B01D61/42; B01D61/44; B01D61/46; B01D61/461; C; C02; C02F; C02F1/00; C02F1/46; C02F1/4604; C02F1/469; C02F1/4693; C25; C25B; C25B1/00; C25B1/01; C25B1/34; B01D2311/00; B01D2311/26; B01D2311/2661; B01D2311/2665; B01D2325/00; B01D2325/12; C02F2201/00; C02F2201/46; C02F2201/461; C02F2201/46105; C02F2201/46115; Y; Y02; Y02A; Y02A20/00; Y02A20/124
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
216 words
In an electrolyticdialysis cell for the concomitant electrolytic decomposition of a part of the alkali metal halide solute of a brine and the electrodialysis of the solute of a further part of said brine, said cell having an anode compartment containing an anode, anolyte inlet means, and outlet means for anolyte and substantially pure halogen, a plurality of cell pairs comprising anion permselective membranes, cation permselective membranes, and intermembrane separators with inlet means for said brine, and outlet means for diluate and concentrate, and preferably a liquid permeable membrane separating said anode from a first neighboring cell pair, and a cathode compartment containing a novel cathode structure, catholyte inlet means and outlet means, and a denuding compartment one wall of which is formed by a surface of said cathode structure, with inlet means for water or caustic soda solution, and outlet means for enriched caustic soda solution and hydrogen, said denuding compartment preferably containing a catalyst for promoting reaction of sodium in a sodium amalgam with water, the improvement consisting of said novel cathode having an immobilized liquid alkali-metal amalgam filling the interconnected micro-pores of said novel cathode structure, said cathode structure being disposed following a neighboring last cell pair and abutting said denuding compartment of said cell, said amalgam and said anode being electrically connected.
Claim 2
Dependent Claim
216 words
In an electrolyticdialysis cell for the concomitant electrolytic decomposition of a part of the alkali metal halide solute of a brine and the electrodialysis of the solute of a further part of said brine, said cell having an anode compartment containing an anode, anolyte inlet means, and outlet means for anolyte and substantially pure halogen, a plurality of cell pairs comprising anion permselective membranes, cation permselective membranes, and intermembrane separators with inlet means for said brine, and outlet means for diluate and concentrate, and preferably a liquid permeable membrane separating said anode from a first neighboring cell pair, and a cathode compartment containing a novel cathode structure, catholyte inlet means and outlet means, and a denuding compartment one wall of which is formed by a surface of said cathode structure, with inlet means for water or caustic soda solution, and outlet means for enriched caustic soda solution and hydrogen, said denuding compartment preferably containing a catalyst for promoting reaction of sodium in a sodium amalgam with water, the improvement consisting of said novel cathode having an immobilized liquid alkali-metal amalgam filling the interconnected micro-pores of said novel cathode structure, said cathode structure being disposed following a neighboring last cell pair and abutting said denuding compartment of said cell, said amalgam and said anode being electrically connected.
Claim 3
Dependent Claim
24 words
The cell as claimed in claim 1 in which the said interconnected micro-porous structure of said novel cathode is constructed of a polymeric resin.
Claim 4
Dependent Claim
29 words
The cell as claimed in claim 2 in which said polymeric resin is selected from the group consisting of polyethylene, polytetrafluorethylene, polypropylene, polyisobutlyene, polyvinylchloride, and natural and synthetic rubbers.
Claim 5
Dependent Claim
29 words
The cell as claimed in claim 1 in which said interconnected micro-pores of said cathode structure have a mean diameter of from about 5 microns to about 70 microns.
Claim 6
Dependent Claim
19 words
The cell as claimed in claim 1 in which the said mercury amalgam is a liquid sodium mercury alloy.
Claim 7
Dependent Claim
29 words
The cell as claimed in claim 1 in which active carbon is disposed between said liquid permeable membrane and the anion permselective membrane of a first neighboring cell pair.
Claim 8
Dependent Claim
23 words
The cell as claimed in claim 1 in which the said catalyst is selected from the group consisting of vanadium, molybdenium and chromium.
Claim 9
Dependent Claim
204 words
In a process, conducted in an electrolyticdialysis cell, for the electrolytic decomposition of a first part of the alkali metal halide solute of a separately maintained aqueous brine to produce substantially pure chlorine and substantially pure caustic soda in concentrated solution and hydrogen, and for the concomitant electrodialysis in said cell of the solute of a further part of said separately maintained aqueous brine to form at least partly desalinated water and salt enriched water, the improvement consisting, in combination, of the electrical discharge of the cations of said first part of said solute to atoms at an immobilized liquid metal amalgam filling the interconnected micro-pores of novel cathode immersed in a separately maintained sea water catholyte, and subsequent reaction of said atoms with water of dilute caustic soda solution in a denuding chamber abutting said novel cathode to form said substantially pure concentrated caustic soda solution and hydrogen, and further consisting, in said combination, of the electrical discharge of the anions of said first part of said solute at an anode immersed in a separately maintained substantially saturated metal chloride solution as anolyte, to form substantially pure chlorine, an electric current being passed between said anode and the amalgam of said novel cathode.
Claim 10
Dependent Claim
204 words
In a process, conducted in an electrolyticdialysis cell, for the electrolytic decomposition of a first part of the alkali metal halide solute of a separately maintained aqueous brine to produce substantially pure chlorine and substantially pure caustic soda in concentrated solution and hydrogen, and for the concomitant electrodialysis in said cell of the solute of a further part of said separately maintained aqueous brine to form at least partly desalinated water and salt enriched water, the improvement consisting, in combination, of the electrical discharge of the cations of said first part of said solute to atoms at an immobilized liquid metal amalgam filling the interconnected micro-pores of novel cathode immersed in a separately maintained sea water catholyte, and subsequent reaction of said atoms with water of dilute caustic soda solution in a denuding chamber abutting said novel cathode to form said substantially pure concentrated caustic soda solution and hydrogen, and further consisting, in said combination, of the electrical discharge of the anions of said first part of said solute at an anode immersed in a separately maintained substantially saturated metal chloride solution as anolyte, to form substantially pure chlorine, an electric current being passed between said anode and the amalgam of said novel cathode.
Claim 11
Dependent Claim
33 words
The process as claimed in claim 8 in which the metal of said substantially saturated metal chloride anolyte is selected from the group consisting of metals having a valence of one to three.
Claim 12
Dependent Claim
28 words
The process as claimed in claim 9 in which the said metal is selected from the group consisting of alkali metals, alkaline earth metals, and iron and aluminum.
Claim 13
Dependent Claim
18 words
The process as claimed in claim 8 in which the said separately maintained aqueous brine is sea water.
Claim 14
Dependent Claim
30 words
The process as claimed in claim 8 in which said sea water has ions removed which form compounds impeding electrical flow prior to use of said water in said cell.
Claim 15
Dependent Claim
217 words
In an electrolyticdialysis cell for the concomitant electrolytic decomposition of a part of the alkali metal halide solute of an aqueous brine and the electrodialysis of the solute of a further part of said brine, said cell having an anode compartment containing an anode, anolyte inlet means only for an aqueous substantially saturated metal chloride solution, and outlet means for anolyte and substantially pure halogen, a plurality of cell pairs comprising anion permselective membranes, cation permselective membranes, and intermembrane separators with inlet means only for (said brine) a brine having a salt concentration no greater than that of sea water, and outlet means alternately for (diluate and concentrate) at least partly desalinated water and salt enriched water, and preferably a liquid permeable membrane separating said anode from a first neighboring cell pair, and a cathode compartment containing a cathode, cathode inlet means only for one of the group selected from substantially salt-free water and aqueous caustic soda solution, and outlet means for enriched caustic soda solution and hydrogen, the improvement consisting of the disposition between the last of said cell pairs and the said cathode of said cell of a novel cation permeable, micro-porous diaphragm, the interconnected micro-pores of which are filled with an immobile liquid alkali metal amalgam, said anode and said cathode being electrically connected.
Claim 16
Dependent Claim
217 words
In an electrolyticdialysis cell for the concomitant electrolytic decomposition of a part of the alkali metal halide solute of an aqueous brine and the electrodialysis of the solute of a further part of said brine, said cell having an anode compartment containing an anode, anolyte inlet means only for an aqueous substantially saturated metal chloride solution, and outlet means for anolyte and substantially pure halogen, a plurality of cell pairs comprising anion permselective membranes, cation permselective membranes, and intermembrane separators with inlet means only for (said brine) a brine having a salt concentration no greater than that of sea water, and outlet means alternately for (diluate and concentrate) at least partly desalinated water and salt enriched water, and preferably a liquid permeable membrane separating said anode from a first neighboring cell pair, and a cathode compartment containing a cathode, cathode inlet means only for one of the group selected from substantially salt-free water and aqueous caustic soda solution, and outlet means for enriched caustic soda solution and hydrogen, the improvement consisting of the disposition between the last of said cell pairs and the said cathode of said cell of a novel cation permeable, micro-porous diaphragm, the interconnected micro-pores of which are filled with an immobile liquid alkali metal amalgam, said anode and said cathode being electrically connected.
Claim 17
Dependent Claim
20 words
The cell as claimed in claim 13 having in combination means for contacting said cathode with an oxygen bearing gas.
Claim 18
Dependent Claim
207 words
In a process conducted in a conventional electrodialysis cell having an anode compartment containing an anode, anolyte inlet means, and outlet means for anolyte and substantially pure halogen, a plurality of cell pairs with inlet means for brine and outlet means for diluate and concentrate, a liquid permeable membrane separating said anode from a first neighboring cell pair, and a cathode compartment containing a cathode, catholyte inlet means, and outlet means for enriched caustic soda solution and hydrogen, said process being conducted for the electrolytic decomposition of a part of the alkali metal halide solute of a separately maintained aqueous brine to produce substantially pure chlorine, a relatively dilute caustic soda solution, and hydrogen, and for the concomitant electrodialysis of the solvent of a further part of said separately maintained aqueous brine to form at least partly desalinated water and salt enriched water, the improvement consisting of the electrical discharge of the anions of said solute at said anode immersed in a separately maintained substantially saturated metal chloride anolyte, an electrical current being passed at a suitable voltage between said anode and said cathode of said cell, for production of said substantially pure chlorine, relatively dilute caustic soda solution and hydrogen, and at least partly desalinated water.
Claim 19
Dependent Claim
207 words
In a process conducted in a conventional electrodialysis cell having an anode compartment containing an anode, anolyte inlet means, and outlet means for anolyte and substantially pure halogen, a plurality of cell pairs with inlet means for brine and outlet means for diluate and concentrate, a liquid permeable membrane separating said anode from a first neighboring cell pair, and a cathode compartment containing a cathode, catholyte inlet means, and outlet means for enriched caustic soda solution and hydrogen, said process being conducted for the electrolytic decomposition of a part of the alkali metal halide solute of a separately maintained aqueous brine to produce substantially pure chlorine, a relatively dilute caustic soda solution, and hydrogen, and for the concomitant electrodialysis of the solvent of a further part of said separately maintained aqueous brine to form at least partly desalinated water and salt enriched water, the improvement consisting of the electrical discharge of the anions of said solute at said anode immersed in a separately maintained substantially saturated metal chloride anolyte, an electrical current being passed at a suitable voltage between said anode and said cathode of said cell, for production of said substantially pure chlorine, relatively dilute caustic soda solution and hydrogen, and at least partly desalinated water.
Claim 20
Dependent Claim
23 words
The cell as claimed in claim 13 in which said anode is immersed in a substantially saturated aqueous metal chloride solution as anolyte.
Claim 21
Dependent Claim
142 words
A process for the concomitant production of desalinated water and chlor-alkali conducted in an electrolyticdialysis cell which includes at least an anode in an anode compartment, a plurality of cell pairs consisting of diluate and concentrate compartments alternately, and a cathode in a cathode compartment, wherein the improvement consists in the concomitant use, in combination, of a separately maintained aqueous substantially saturated, metal chloride solution in said anode compartment, in further combination in the use of a brine having a salt concentration no greater than that of sea water in said diluate compartments of said cell pairs, and in still further combination in the use of one of the group selected from substantially salt-fee water and aqueous caustic soda solution in said cathode compartment, said anode and said cathode being electrically connected at a suitable voltage to a source of D.C. current.
Claim 22
Dependent Claim
142 words
A process for the concomitant production of desalinated water and chlor-alkali conducted in an electrolyticdialysis cell which includes at least an anode in an anode compartment, a plurality of cell pairs consisting of diluate and concentrate compartments alternately, and a cathode in a cathode compartment, wherein the improvement consists in the concomitant use, in combination, of a separately maintained aqueous substantially saturated, metal chloride solution in said anode compartment, in further combination in the use of a brine having a salt concentration no greater than that of sea water in said diluate compartments of said cell pairs, and in still further combination in the use of one of the group selected from substantially salt-fee water and aqueous caustic soda solution in said cathode compartment, said anode and said cathode being electrically connected at a suitable voltage to a source of D.C. current.
Claim 23
Dependent Claim
28 words
The process as claimed in claim 17, wherein the metal in said metal chloride is selected from the group of metals having a valence of one to three.
Claim 24
Dependent Claim
167 words
A process for the concomitant production of desalinated water and chlor-alkali conducted in an electrolyticdialysis cell which includes at least an anode in an anode compartment, a plurality of cell pairs consisting of diluate and concentrate compartments alternately, and a cathode in a cathode compartment, in which is used concomitantly, and in combination, a separately maintained aqueous substantially saturated metal chloride solution in said anode compartment, in further combination is used a brine having a salt concentration no greater than that of sea water in said diluate compartments of said cell pairs, and in still further combination is used one of the group selected from substantially salt-free water and aqueous caustic soda solution in said cathode compartment, wherein the improvement lies in passing cations under the influence of an electric field thru a novel cation-permeable, microporous diaphragm, the interconnected micropores of which are filled with an immobile, liquid alkali-metal amalgam, said anode and said cathode being electrically connected at suitable voltage to a source of D.C. current.
Claim 25
Dependent Claim
167 words
A process for the concomitant production of desalinated water and chlor-alkali conducted in an electrolyticdialysis cell which includes at least an anode in an anode compartment, a plurality of cell pairs consisting of diluate and concentrate compartments alternately, and a cathode in a cathode compartment, in which is used concomitantly, and in combination, a separately maintained aqueous substantially saturated metal chloride solution in said anode compartment, in further combination is used a brine having a salt concentration no greater than that of sea water in said diluate compartments of said cell pairs, and in still further combination is used one of the group selected from substantially salt-free water and aqueous caustic soda solution in said cathode compartment, wherein the improvement lies in passing cations under the influence of an electric field thru a novel cation-permeable, microporous diaphragm, the interconnected micropores of which are filled with an immobile, liquid alkali-metal amalgam, said anode and said cathode being electrically connected at suitable voltage to a source of D.C. current.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-10-19 | 1985-04-20 | 1985-10-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-10-19 | 1989-04-20 | 1989-10-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-10-19 | 1993-04-20 | 1993-10-20 | $7700.00 | Window Closed / Lapsed |