Using Anion Selective Membrane Patents (Class 204/539)
  • Patent number: 11702753
    Abstract: The invention generally relates an apparatus for generation of hydrogen and oxygen gases by utilizing seawater. The invention also relates to a method of making hydrogen and oxygen gas by utilizing anion exchange membranes and seawater. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present invention.
    Type: Grant
    Filed: July 9, 2020
    Date of Patent: July 18, 2023
    Assignee: University of Alaska Fairbanks
    Inventor: Andrew McDonnell
  • Patent number: 11613481
    Abstract: The present invention relates to a method for electrochemical purification of an aqueous solution comprising the steps of: providing a cathode and an anode to an aqueous solution, wherein said aqueous solution comprises soluble ions of at least one toxic heavy metal and wherein said cathode comprises an outer surface, which outer surface comprises a noble metal; applying an absolute potential to said cathode and wherein said absolute potential of said cathode drives the formation of an alloy comprising said noble metal and said at least one toxic heavy metal.
    Type: Grant
    Filed: October 29, 2018
    Date of Patent: March 28, 2023
    Assignee: ATIUM AB
    Inventors: Björn Wickman, Cristian Tunsu
  • Publication number: 20150014169
    Abstract: The disclosure relates to efficient methods of controlling biological conversions while simultaneously removing and converting some of the generated products. More specifically, and, for example, the disclosure discloses electrochemical processes to remove and capture potentially toxic ammonium during anaerobic digestions and to remove and capture carboxylic acids during bioethanol production. The disclosure can, thus, be used to enhance bioproduction processes via controlling pH and/or reduction/oxidation, in combination with in situ product recovery.
    Type: Application
    Filed: January 30, 2013
    Publication date: January 15, 2015
    Inventors: Korneel Rabaey, Christian Stevens
  • Patent number: 8921088
    Abstract: The present invention includes a method for harvesting or separating one or more biological cells from an aqueous feed, a stream, a suspension, or any combinations thereof by providing the aqueous feed, the stream, or the suspension comprising the one or more biological cells in a tank or a vessel; providing one or more ion-exchange resins, wherein the ion-exchange resin is an anion-exchange resin; contacting the anion-exchange resin with the aqueous feed; binding the one or more biological cells to the anion-exchange resin; releasing or eluting the bound one or more biological cells by changing the pH; and collecting the released one or more biological cells to obtain a concentrated slurry or suspension of the one or more biological cells.
    Type: Grant
    Filed: October 3, 2012
    Date of Patent: December 30, 2014
    Assignee: Board of Regents, The University of Texas System
    Inventors: Martin Poenie, Jessica Jones
  • Patent number: 8900435
    Abstract: Carbon dioxide can be separated from gas streams using ion exchange, such as in an electrochemical cell. An anion exchange membrane can be configured to increase the efficiency of the system and to permit the flow of the carbon-containing ions within the system while reducing diffusion of protons and/or hydroxyl ions. A gas stream containing carbon dioxide can be introduced to the system on the cathode side, while a source of hydrogen-containing molecules can be introduced on the anode side. Operation of the system can separate the carbon dioxide from the gas stream and provide it at a separate outlet.
    Type: Grant
    Filed: December 19, 2007
    Date of Patent: December 2, 2014
    Assignee: Palo Alto Research Center Incorporated
    Inventor: Karl Anthony Littau
  • Publication number: 20140305800
    Abstract: There is disclosed an electrochemical cell for treating water comprising at least one water chamber configured to hold water to be treated; at least one redox electrode comprising reactants capable of accepting and having a reversible redox reaction with at least one negative ion in the water; at least one intercalation electrode capable of accommodating and intercalating at least one positive ion in the water, wherein the intercalation electrode is immersed in the water chamber or separated from the water chamber by an optional porous separator; and an anion exchange membrane separating the redox electrode from the water chamber. The cell can be used to desalinate water having a wide range of salinities, including sea water, and brackish water. The cell can also be used to collect salt, which can subsequently used to concentrate industrial brine. Methods for using the electrochemical cell to treat water, such as desalinate saline solutions are disclosed.
    Type: Application
    Filed: April 16, 2013
    Publication date: October 16, 2014
    Applicant: Palo Alto Research Center Incorporated
    Inventor: Palo Alto Research Center Incorporated
  • Publication number: 20140251810
    Abstract: The present invention relates to a method for reducing the ionic strength or the concentration of certain polyvalent ions in aqueous dispersions of organic binding agents or inorganic solid bodies by electrodialysis, and a cell package suitable for use in the method. This method permits stabilization of aqueous compositions of the dispersed components by regulating the ionic strength or the concentration of certain polyvalent ions thereby increasing the durability and throughput times of coating baths. More particularly, the method is used in removing polyvalent metal cations from anionically stabilized aqueous binding agent dispersions.
    Type: Application
    Filed: May 22, 2014
    Publication date: September 11, 2014
    Applicant: Henkel AG & Co. KGaA
    Inventors: Klaus LEPA, Ulrich DAWIDOWSKI
  • Publication number: 20130186760
    Abstract: A method for extracting and enriching lithium, including: (a) providing an electrodialysis device including an electrodialysis cell; (b) dividing the electrodialysis cell into a lithium salt chamber and a brine chamber using an anion exchange membrane; (c) filling the brine chamber with salt lake brine; (d) filling the lithium salt chamber with a Mg2+ free supporting electrolyte solution; (e) placing a conductive substrate coated with an ion sieve in the brine chamber to operate as a cathode; (f) placing a conductive substrate coated with a lithium-intercalated ion sieve in the lithium salt chamber to operate as an anode; and (g) carrying out an electrodialysis.
    Type: Application
    Filed: March 12, 2013
    Publication date: July 25, 2013
    Applicant: CENTRAL SOUTH UNIVERSITY
    Inventor: CENTRAL SOUTH UNIVERSITY
  • Publication number: 20130008791
    Abstract: An electrically-driven separation apparatus can be utilized to desalinate seawater and/or brackish water to provide irrigation water having a desired sodium adsorption ratio (SAR).
    Type: Application
    Filed: August 29, 2012
    Publication date: January 10, 2013
    Applicant: SIEMENS INDUSTRY, INC.
    Inventors: Gary C. Ganzi, Evgeniya Freydina, Anil D. Jha, Li-Shiang Liang, Frederick C. Wilkins
  • Publication number: 20120217162
    Abstract: A nitrogen compound-containing acidic liquid such as a monoethanolamine-containing dilute hydrochloric acid waste liquid discharged during the regeneration of condensate demineralizers in nuclear power plants or thermal power plants is efficiently and economically treated. A neutralization dialysis device 2 is provided in which a raw water chamber 22 and an alkaline solution chamber 23 are partitioned from each other with an anion exchange membrane 21. The nitrogen compound-containing acidic liquid is passed through the raw water chamber 22, while an alkaline solution is passed through the alkaline solution chamber 23, thereby neutralizing and demineralizing the acidic liquid. Thereafter, the nitrogen compound contained in the neutralized demineralized liquid is concentrated with an electrodeionizer 4. The neutralization dialysis treatment using the anion exchange membrane 21 and the alkaline solution can neutralize and demineralize the nitrogen compound-containing acidic liquid.
    Type: Application
    Filed: November 9, 2010
    Publication date: August 30, 2012
    Applicant: KURITA WATER INDUSTRIES LTD.
    Inventors: Hideyuki Komori, Nobuhiro Orita
  • Patent number: 8241482
    Abstract: The invention is directed to a process for recovering acids from mixtures containing them, in particular organic acids and amino acids, such as acids produced by fermentation in a fermentation broth. The process of the invention comprises contacting a loaded extractant with a solution containing hydroxide ions in the presence of at least one cathode and at least one anode, wherein said hydroxide ions are produced by using said cathode, whereby said acid is converted to its anionic form, by which it can be removed from said extractant and can migrate in the direction of the anode.
    Type: Grant
    Filed: November 18, 2005
    Date of Patent: August 14, 2012
    Assignee: Nederlandse Organisatie voor toegepast-natuurwetenschappelijk Onderzoek TNO
    Inventors: Joost Van Erkel, Earl Lawrence Vincent Goetheer
  • Patent number: 8110517
    Abstract: The invention relates to a composite or a composite membrane consisting of an ionomer and of an inorganic optionally functionalized phyllosilicate. The isomer can be: (a) a cation exchange polymer; (b) an anion exchange polymer; (c) a polymer containing both anion exchanger groupings as well as cation exchanger groupings on the polymer chain; or (d) a blend consisting of (a) and (b), whereby the mixture ratio can range from 100% (a) to 100% (b). The blend can be ionically and even covalently cross-linked. The inorganic constituents can be selected from the group consisting of phyllosilicates or tectosilicates.
    Type: Grant
    Filed: October 21, 2009
    Date of Patent: February 7, 2012
    Inventors: Jochen Kerres, Thomas Häring, Rima Häring
  • Patent number: 8088261
    Abstract: An electrochemical cell for producing copper having a dense graphite anode electrode and a dense graphite cathode electrode disposed in a CuCl solution. An anion exchange membrane made of poly(ethylene vinyl alcohol) and polyethylenimine cross-linked with a cross-linking agent selected from the group consisting of acetone, formaldehyde, glyoxal, glutaraldehyde, and mixtures thereof is disposed between the two electrodes.
    Type: Grant
    Filed: May 15, 2007
    Date of Patent: January 3, 2012
    Assignee: Gas Technology Institute
    Inventors: Qinbai Fan, Renxuan Liu
  • Publication number: 20100224492
    Abstract: Systems and methods for hemodialysis or peritoneal dialysis having integrated electrodeionization capabilities are provided. In an embodiment, the dialysis system includes a carbon source, a urease source and an electrodeionization unit. The carbon source and urease source can be in the form of removable cartridges.
    Type: Application
    Filed: March 5, 2010
    Publication date: September 9, 2010
    Applicants: BAXTER INTERNATIONAL INC., BAXTER HEALTHCARE S.A.
    Inventors: Yuanpang Samuel Ding, Ying-Cheng Lo, Joshua James Miller, Justin Rohde, Sujatha Karoor
  • Patent number: 7662267
    Abstract: An improved apparatus and operating method related thereto for deionizing water to produce substantially pure water using electric field and ion exchange materials are disclosed, including embodiments incorporating one or more of the novel features of brine and electrode streams flowing in a direction counter-current to the stream being deionized, a filling of the brine stream with stratified ion exchange materials, a stream mixing feature for mixing the stream being deionized, a gas removal feature for removal of gases, a spiral-wound embodiment of an electrodialysis device according to the invention, and a method for determining the preferred operating current for electrodialysis systems according to this invention.
    Type: Grant
    Filed: August 10, 2001
    Date of Patent: February 16, 2010
    Assignee: Ionics, Incorporated
    Inventors: William W. Carson, Keith J. Sims, Oleg Grebenyuk, Thomas J. Susa, Hilda R. Zanapalidou, Wayne A. McRae, Russell J. MacDonald
  • Patent number: 7544278
    Abstract: The invention includes novel anion exchange membranes formed by in situ polymerization of at least one monomer, polymer or copolymer on a woven support membrane and their methods of formation. The woven support membrane is preferably a woven PVC membrane. The invention also includes novel cation exchange membranes with or without woven support membranes and their methods of formation. The invention encompasses a process for using the membranes in electrodialysis of ionic solutions and in particular industrial effluents or brackish water or seawater. The electrodialysis process need not include a step to remove excess ions prior to electrodialysis and produces less waste by-product and/or by-products which can be recycled.
    Type: Grant
    Filed: April 19, 2004
    Date of Patent: June 9, 2009
    Assignee: Seventy-Seventh Meridian Corporation, LLC
    Inventors: Tejraj Aminabhavi, Padmakar V. Kulkarni, Mahadevappa Y. Kariduraganavar
  • Publication number: 20080245667
    Abstract: Apparatus is described for removing ionisable impurities from an electrolyte solution in an electromembrane device. The apparatus comprises means for recirculating the electrolyte solution between the cathode and the anode, and means for transferring selected ions from the electrolyte solution into a separate stream upon application of a current.
    Type: Application
    Filed: March 9, 2005
    Publication date: October 9, 2008
    Inventors: Christopher Peter Jones, Peter James Mawle
  • Patent number: 7217349
    Abstract: The invention pertains to a method of separating multivalent ions and lactate ions from a fermentation broth comprising a multivalent ion lactate salt by using an electrodialysis or electrolysis apparatus, comprising the steps of introducing the broth wherein the multivalent ion concentration is at least 0.1 mole/l, the lactate ion concentration is less than 300 g/l, and less than 10 mole % of the lactate ion are other negatively charged ions, into a first compartment of the electrodialysis or electrolysis apparatus, which compartment is limited by an anion-selective or non-selective membrane and a cathode, and wherein the multivalent ion is converted to obtain a residual stream comprising the hydroxide of the multivalent ion, and the lactate ion is transported through the anion-selective or non-selective membrane into a second compartment limited by the anion-selective or non-selective membrane and an anode, after which the lactate ion is neutralized to lactic acid.
    Type: Grant
    Filed: October 28, 2003
    Date of Patent: May 15, 2007
    Assignee: Purac Biochem B.V.
    Inventors: Peter Baets, Willem Jacob Groot
  • Patent number: 7144735
    Abstract: An electrodialysis method and apparatus are provided for treating a sample including trace metals in a matrix. Advantageously, the present invention allows for highly accurate detection of trace contaminants in a solution sample, in particular trace metals, substantially in real-time and on-line. The present invention includes flowing a carrier solution through a carrier solution channel separated from a sample channel by a membrane. A component of the carrier solution is diffused through the membrane into the sample channel to stabilize trace metals in the solution sample for subsequent analysis. Simultaneously, the matrix is eliminated, neutralized, and/or modified for enhanced analysis.
    Type: Grant
    Filed: September 5, 2003
    Date of Patent: December 5, 2006
    Assignee: Metara, Inc.
    Inventor: Harmesh K. Saini
  • Patent number: 7049020
    Abstract: The invention relates to a composite or a composite membrane consisting of an ionomer and of an inorganic optionally functionalized phyllosilicate. The isomer can be: (a) a cation exchange polymer; (b) an anion exchange polymer; (c) a polymer containing both anion exchanger groupings as well as cation exchanger groupings on the polymer chain; or (d) a blend consisting of (a) and (b), whereby the mixture ratio can range from 100% (a) to 100% (b). The blend can be ionically and even covalently cross-linked. The inorganic constituents can be selected from the group consisting of phyllosilicates or tectosilicates.
    Type: Grant
    Filed: October 30, 2001
    Date of Patent: May 23, 2006
    Inventors: Jochen Kerres, Thomas Haring, Rima Haring
  • Patent number: 6830671
    Abstract: An ion-exchange membrane having excellent resistance against organic fouling by high molecular weight organic ions etc. and showing low electric resistance is provided. Said ion-exchange membrane is characterized by that a polyether compound containing polyalkylene glycol chain, such as polyethylene glycol, polypropylene glycol, their derivatives, etc., is fixed on the surface and/or inside of the membrane. As examples of the mode of the fixation there are mentioned fixation by entanglement of the molecules forming the membrane and the molecules of the polyether compound, physical fixation of both molecules by the anchor effect, and chemical fixation of both molecules by the formation of covalent bond or ionic bond. Said ion-exchange membrane can be preferably used in case of removing low molecular weight electrolytes from an aqueous solution containing low molecular weight electrolytes and high molecular weight organic ions etc. through electrodialysis.
    Type: Grant
    Filed: June 28, 2002
    Date of Patent: December 14, 2004
    Assignee: Tokuyama Corporation
    Inventors: Toshio Aritomi, Minoru Kawashima
  • Patent number: 6800185
    Abstract: Herein are disclosed a method for producing a basic amino acid solution which comprises subjecting a solution of a basic amino acid salt to electrodialysis with the use of an electrodialyser equipped with cation exchange membranes and anion exchange membranes in combination, wherein an alkali aqueous solution is added to the solution of a basic amino acid salt during the electrodialysis, whereby not only desalting is caused but also the counter anions of the basic amino acid are removed to such degree that the said counter anions remain in an amount of 40 mol % or smaller based on the basic amino acid, as well as a method for producing a basic amino acid solution which comprises subjecting a solution of a basic amino acid salt to electrodialysis with the use of an electrodialyser equipped with anion exchange membrane alone, wherein an alkali aqueous solution is added to the solution of a basic amino acid salt to adjust the pH of the solution to 7 to 10 during the electrodialysis, whereby the counter anions ar
    Type: Grant
    Filed: March 15, 2002
    Date of Patent: October 5, 2004
    Assignee: Ajinomoto Co., Inc.
    Inventors: Kazuhiro Hasegawa, Toshiya Tanabe, Yasuhiro Maruta
  • Publication number: 20020094466
    Abstract: The invention relates to a composite or a composite membrane consisting of an ionomer and of an inorganic optionally functionalized phyllosilicate. The isomer can be: (a) a cation exchange polymer; (b) an anion exchange polymer; (c) a polymer containing both anion exchanger groupings as well as cation exchanger groupings on the polymer chain; or (d) a blend consisting of (a) and (b), whereby the mixture ratio can range from 100% (a) to 100% (b). The blend can be ionically and even covalently cross-linked. The inorganic constituents can be selected from the group consisting of phyllosilicates or tectosilicates.
    Type: Application
    Filed: October 30, 2001
    Publication date: July 18, 2002
    Inventors: Jochen Kerres, Thomas Haring, Rima Haring
  • Patent number: 5993629
    Abstract: An electrodialysis method using a bipolar membrane (BP) for regenerating acids, wherein a series of base (B), acid (A) and salt (S) compartments are provided between a positive electrode (anode) and a negative electrode (cathode), said compartments being defined by a series of membranes: cationic, bipolar, anionic, cationic, bipolar and so forth, and a solution being circulated through each compartment. An additional anionic membrane (10) is applied to the anionic side (11) of the bipolar membrane (BP) with no discernible gap therebetween so that contamination of the acid compartment by cations is reduced.
    Type: Grant
    Filed: July 17, 1997
    Date of Patent: November 30, 1999
    Assignee: Elf Atochem S.A.
    Inventors: Claude Gavach, Christian Gancet, Alfred Mirassou, Frederic Perie
  • Patent number: 5980724
    Abstract: Described is a method of electrochemically converting .alpha.-halohydrins, e.g., 1-chloro-2-hydroxypropane and 1,3-dichloro-2-hydroxypropane, to epoxides, e.g., propylene oxide and epichlorohydrin. An electrolytic cell is provided having (1) a catholyte compartment containing a cathode assembly comprising a cathode and a bipolar ion exchange membrane, (2) an anode compartment containing an anode assembly comprising either (a) a hydrogen consuming gas diffusion anode and a current collecting electrode or (b) a hydrogen consuming gas diffusion anode which is fixedly held between a hydraulic barrier and a current collecting electrode, and (3) at least one pair of intermediate compartments separating the catholyte and anode compartments and separated from each other by an anion exchange membrane. The following are introduced into the cell: a first aqueous conductive electrolyte solution into the catholyte compartment; hydrogen gas into the anode compartment; an aqueous solution of .alpha.
    Type: Grant
    Filed: July 9, 1998
    Date of Patent: November 9, 1999
    Assignee: PPG Industries Ohio, Inc.
    Inventors: David G. Roberts, Peter C. Foller, Robert H. Tang, Yingchao Zhang
  • Patent number: 5906722
    Abstract: Describes a method of electrochemically converting amine hydrohalide, e.g., ethyleneamine hydrochloride, into free amine, e.g., free ethyleneamine. A three compartment electrolytic cell is provided having (1) a catholyte compartment containing a cathode assembly comprising a cathode and an anion exchange membrane, (2) an anode compartment containing an anode assembly comprising either (a) a hydrogen consuming gas diffusion anode and a current collecting electrode or (b) a hydrogen consuming gas diffusion anode which is fixedly held between a hydraulic barrier and a current collecting electrode, and (3) an intermediate compartment separated from the catholyte and anode compartments by the anion exchange membrane and either (i) the hydrogen consuming gas diffusion anode or (ii) the hydraulic barrier respectively.
    Type: Grant
    Filed: August 18, 1997
    Date of Patent: May 25, 1999
    Assignee: PPG Industries, Inc.
    Inventors: Peter C. Foller, David G. Roberts, Robert H. Tang
  • Patent number: 5904829
    Abstract: Describes a method of electreochemically converting amine hydrohalide, e.g., amine hydrochloride, into free amine, e.g., free ethyleneamine. An electrolytic cell is provided having (1) a catholyte compartment containing a cathode assembly comprising a cathode and a bipolar ion exchange membrane, (2) an anode compartment containing an anode assembly comprising either (a) a hydrogen consuming gas diffusion anode and a current collecting electrode or (b) a hydrogen consuming gas diffusion anode which is fixedly held between a hydraulic barrier and a current collecting electrode, and (3) at least one pair of intermediate compartments separating the catholyte and anode compartments and separated from each other by an anion exchange membrane.
    Type: Grant
    Filed: August 18, 1997
    Date of Patent: May 18, 1999
    Assignee: PPG Industries, Inc.
    Inventors: Peter C. Foller, David G. Roberts, Robert H. Tang
  • Patent number: 5900133
    Abstract: Describes a method of electrochemically converting amine hydrohalide, e.g., ethyleneamine hydrochloride, into free amine, e.g., free ethyleneamine. A three compartment electrolytic cell is provided having (1) a catholyte compartment containing a cathode assembly comprising a cathode and anion exchange membrane, (2) an anolyte compartment containing an anode assembly comprising an anode and a cation exchange membrane, and (3) an intermediate compartment separated from the catholyte and anolyte compartments by the anion and cation exchange membranes respectively. An aqueous solution of amine hydrohalide is charged to the catholyte compartment, while hydrogen halide solutions are charged to the intermediate and anolyte compartments. Direct current is passed through the electrolytic cell and an aqueous solution comprising free amine is removed from the catholyte compartment.
    Type: Grant
    Filed: August 18, 1997
    Date of Patent: May 4, 1999
    Assignee: PPG Industries, Inc.
    Inventors: Peter C. Foller, David G. Roberts, Robert H. Tang, James R. Franks
  • Patent number: 5882501
    Abstract: Describes a method of electrochemically converting amine hydrohalide, e.g., ethyleneamine hydrochloride, into free amine, e.g., free ethyleneamine, by charging an aqueous solution of amine hydrohalide to the catholyte compartment of an electrolytic cell, which contains a cathode, charging hydrogen gas to the anode compartment of the cell, which contains an anode assembly comprised of a hydrogen consuming gas diffusion anode fixedly held between a current collecting electrode and an anion exchange membrane. The catholyte and anode compartments of the cell are separated by the anion exchange membrane. An amine hydrohalide solution containing free amine is removed from the catholyte compartment.
    Type: Grant
    Filed: August 18, 1997
    Date of Patent: March 16, 1999
    Assignee: PPG Industries, Inc.
    Inventors: Peter C. Foller, David G. Roberts, Robert H. Tang
  • Patent number: 5772013
    Abstract: A method is disclosed for producing di- and more highly oxidized carboxylic acids from a compound selected from a first group consisting of carbohydrates, carbohydrate derivatives and carbohydrate derivatives having more than one primary alcohol group, comprising oxidizing, in an aqueous solution in a concentration between 0.1% and 60%, the compound selected from said first group and a compound selected from a second group consisting of monooxidized carbohydrates, monooxidized carbohydrate derivatives and monooxidized carbohydrate derivatives having more than one primary alcohol group, with one of oxygen and an oxygen-containing gas, on one of a noble metal catalyst and a mixed metal catalyst; electrodialyzing the oxidized compounds in at least one electrodialysis stage; and removing said di- and more highly oxidized carboxylic acids in said at least one electrodialysis stage.
    Type: Grant
    Filed: November 14, 1996
    Date of Patent: June 30, 1998
    Assignee: Sudzucker Akiengesellschaft Mannheim/Ochsenfurt
    Inventors: Markwart Kunz, Andreas Schwarz, Jorg Kowalczyk
  • Patent number: 5709789
    Abstract: The present invention relates to a method of preparing hydroxylamine in an electrochemical cell, comprising the steps of: providing an electrochemical cell comprising an anode, a cathode, a bipolar membrane positioned between the anode and the cathode, the bipolar membrane having an anion selective side facing the anode and a cation selective side facing the cathode, and a divider positioned between the bipolar membrane and the anode, thereby defining a feed compartment on the cation selective side of the bipolar membrane, a recovery compartment on the anion selective side of the bipolar membrane, and an anolyte compartment between the divider and the anode; charging the feed compartment with an acidic electrolyte and the recovery and anolyte compartments with a solution; introducing nitrogen containing gas into the feed compartment; passing a current through the electrochemical cell thereby producing hydroxylammonium salt in the feed compartment; transferring at least a portion of the hydroxylammonium salt f
    Type: Grant
    Filed: October 23, 1996
    Date of Patent: January 20, 1998
    Assignee: Sachem, Inc.
    Inventors: Christopher D. Shay, Hossein Sharifian
  • Patent number: 5609742
    Abstract: An electrolytic process and apparatus is disclosed for oxidizing or reducing inorganic and organic species, especially in dilute aqueous solutions. The electrolytic reactor includes an anode and cathode in contact with a packed bed of particulate ion exchange material which establishes an infinite number of transfer sites in the electrolyte to significantly increase the mobility of the ionic species to be oxidized or reduced toward the anode or cathode, respectively. The ion exchange material is cationic for oxidation and anionic for reduction, or a combination of both for special circumstances. Preferably, the ion exchange material is treated to convert a portion of the transfer sites to semiconductor junctions which act as mini anodes, or cathodes, to significantly increase the capacity of the reactor to oxidize or reduce the species to be treated. Exemplary applications for the disclosed electrolytic process and apparatus are the conversion of halides to halous acids in dilute solutions.
    Type: Grant
    Filed: March 9, 1995
    Date of Patent: March 11, 1997
    Assignee: Halox Technologies Corporation
    Inventors: Richard L. Sampson, Allison H. Sampson
  • Patent number: 5567293
    Abstract: A process for the recovery of alkali metal hydroxide and acid from the alkali metal salts of monovalent anions which are mixed with the alkali metal salts of multivalent anions employs a water-splitting system composed of bipolar membranes in conjunction with ion-selective membranes; a two-compartment cell employs monovalent anion-selective membranes to define salt/base and acid compartments with the bipolar membranes, and a three-compartment cell employs, monovalent anion-selective and cation-selective membranes to define with the bipolar membranes, acid, salt and base compartments; the process has particular applicability to the conversion of the sodium/potassium chloride portion of the Electrostatic Precipitator (ESP) Catch of the recovery boiler of coastal and/or closed-cycle kraft pulp mills, a mixture of mostly sodium/potassium sulphate and chloride, into sodium/potassium hydroxide and hydrochloric acid; the remaining sodium/potassium sulphate solution, depleted in chloride, can thus be used as sodium/s
    Type: Grant
    Filed: December 22, 1994
    Date of Patent: October 22, 1996
    Assignee: Pulp and Paper Research Institute of Canada
    Inventors: Michael Paleologou, Richard M. Berry, Rokhsareh Thompson, James T. Wearing
  • Patent number: 5536384
    Abstract: A process using an electrodialysis system employing cation-selective membranes and anion-selective membranes, particularly monovalent anion-selective membranes is used to separate kraft pulping liquors into two streams; one that is rich in sulphides (to be used in the initial stage of pulping), and another that is poor in sulphides (to be used in the final stage of pulping). By separating pulping liquors in this way, the sulphur balance in the kraft process can be maintained while obtaining the benefits of modified pulping. The same electrodialytic system can be used to separate green and polysulphide liquors into sulphide-rich and sulphide-poor components.
    Type: Grant
    Filed: February 14, 1995
    Date of Patent: July 16, 1996
    Assignee: Pulp and Paper Research Institute of Canada
    Inventors: Rokhsareh Thompson, Michael Paleologou, Richard M. Berry