Organic Patents (Class 204/296)
  • Patent number: 5609974
    Abstract: This invention is directed to a novel solid polymer electrolyte more particularly thin film terpolymer networks are disclosed that are highly conductive at ambient temperatures. This solid polymer electrolyte can be produced as a thin film that results from the polymerization of three selected monomers together with a lithium salt and plasticizers. The resulting solid polymer electrolyte does have excellent mechanical properties and ionic conductivity at ambient temperatures and can be used in the fabrication of a solid state battery and other solid state electrochemical devices such as supercapacitors, fuel cells, sensors, electrochromic devices or the like.
    Type: Grant
    Filed: August 4, 1995
    Date of Patent: March 11, 1997
    Assignee: Battery Engineering, Inc.
    Inventor: Luying Sun
  • Patent number: 5599639
    Abstract: An electrolytic membrane for use in fuel cell includes a fluid-imbibed acidified polybenzimidazole resin. The resin is alkyl or aryl sulfonated or alkyl or aryl phosphonated, preferably with a degree of substitution of from 15 to about 60 per cent.
    Type: Grant
    Filed: October 27, 1995
    Date of Patent: February 4, 1997
    Assignee: Hoechst Celanese Corporation
    Inventors: Michael J. Sansone, Frank J. Onorato, Naoya Ogata
  • Patent number: 5599614
    Abstract: A composite membrane is provided which includes a base material and an ion exchange resin. The base material has a microstructure characterized by nodes interconnected by fibrils, or a microstructure characterized by fibrils with no nodes present. The ion exchange resin substantially impregnates the membrane such that the membrane is essentially air impermeable.
    Type: Grant
    Filed: November 21, 1995
    Date of Patent: February 4, 1997
    Assignee: W. L. Gore & Associates, Inc.
    Inventors: Bamdad Bahar, Alex R. Hobson, Jeffrey A. Kolde
  • Patent number: 5576115
    Abstract: Composite, ternary, polymeric system formed by intimately mixing a polymeric compound, a metal salt, and a ceramic additive acting both as agent promoting the transport features (conductivity and ion mobility) and as stabilizer of the chemical characteristics (compatibility with the electrode materials) of the polymeric electrolyte.
    Type: Grant
    Filed: April 17, 1995
    Date of Patent: November 19, 1996
    Assignee: Ente per le Nuove Tecnologie, L'Energia e L'Ambiente (ENEA)
    Inventors: Federico Capuano, Fausto Croce, Bruno Scrosati
  • Patent number: 5571392
    Abstract: A solid ion conductive polymer electrolyte for use particularly in rechargeable batteries, capacitors and other electrochemical devices is comprised mainly of a hydroxyalkyl polysaccharide or a hydroxyalkyl polysaccharide derivative, a diester compound containing a polyoxyalkylene component, a monoester compound containing a polyoxyalkylene component and an ion conductive metallic salt.
    Type: Grant
    Filed: November 22, 1995
    Date of Patent: November 5, 1996
    Assignees: Nisshinbo Industries, Inc., Sanyo Electric Co., Ltd.
    Inventors: Takaya Sato, Hiroshi Yoshida, Soichiro Takenishi, Yasunobu Kodama, Tsukasa Ito, Takashi Sakai
  • Patent number: 5556524
    Abstract: The invention relates to an electron-conducting molecular preparation designed to act as a conductor by receiving an electron at its one end and conducting the electron along its molecular structure to its other end. The molecule in the preparation has the following general formula (I): ##STR1## wherein n represents an integer from 1 to 12the groups X and Y are identical or different and denote functional substituents bound to the pyridine nitrogen, or one or both of X and Y are absent, andR, being identical or different, represent a hydrogen atom or an aliphatic side chain introduced for enhancing the solubility of the molecule in organic solvents, for example a branched or unbranched alkyl or alkoxy group containing any number of carbon atoms.The molecular preparations can be incorporated in a substantially insulating membrane to act as conductors between an electroactive species and an electrode in diagnostic determinations.
    Type: Grant
    Filed: February 16, 1995
    Date of Patent: September 17, 1996
    Assignee: Valtion Teknillinen Tutkimuskeskus
    Inventor: Martin Albers
  • Patent number: 5547550
    Abstract: Diaphragm for use in cells for the electrolysis of alkaline halide solutions comprising: 100 parts by weight of asbestos fibers, 30 to 70 parts by weight of silica-based derivatives and 20 to 60 parts by weight of fluorinated polymers, deposited on a porous material. The weight ratio of the fluorinated polymers and the silica-based derivatives is between 0.6 to 1.2 and preferably between 0.6 to 0.9 with the exception of a diaphragm obtained by depositing a suspension comprising 100 parts by dry weight of asbestos fibers, 30 parts by dry weight of silica-based derivatives, 25 parts by dry weight of fluorinated polymers and 1.5 parts by dry weight of a thickening agent. The invention also concerns a method for the preparation of an optionally microporous diaphragm. The diaphragms of the invention are especially useful in aqueous alkaline halide solutions electrolysis cells.
    Type: Grant
    Filed: December 15, 1994
    Date of Patent: August 20, 1996
    Assignee: Rhone-Poulenc Chimie
    Inventors: Fr ed eric Kuntzburger, Jean-Claude Magne
  • Patent number: 5547551
    Abstract: An ultra-thin composite membrane is provided which includes a base material and an ion exchange resin. The base material is a membrane which is defined by a thickness of less than 1 mil (0.025 mm) and a microstructure characterized by nodes interconnected by fibrils, or a microstructure characterized by fibrils with no nodes present. The ion exchange resin substantially impregnates the membrane such that the membrane is essentially air impermeable.
    Type: Grant
    Filed: March 15, 1995
    Date of Patent: August 20, 1996
    Assignee: W. L. Gore & Associates, Inc.
    Inventors: Bamdad Bahar, Alex R. Hobson, Jeffrey A. Kolde, David Zuckerbrod
  • Patent number: 5538605
    Abstract: A self-contained, gas-generating electrochemical cell has been invented. The cell contains an anode which is exposed to water or water containing material, a water permeable, ion-conducting separator between the anode from the cathode and a cathode composed of an electrochemically decomposable chemical compound which produces water in the presence of protons and electrons.An exemplary cell contains silver oxide as a principal component of the cathode, water as the principal anode component and a proton conducting membrane. The silver oxide reacts with protons electrically driven through said membrane and electrons from a power-source to form elemental silver and water. Deposition of elemental silver in the cathode compartment is advantageous inasmuch as it improves the electronic conductivity of the material in the cathode compartment. Water, in the anode, decomposes to protons and molecular oxygen while releasing electrons.
    Type: Grant
    Filed: September 6, 1994
    Date of Patent: July 23, 1996
    Assignee: Ceramatec, Inc.
    Inventors: Ashok V. Joshi, John H. Gordon
  • Patent number: 5525436
    Abstract: The subject invention relates to solid polymer electrolyte membranes comprising proton conducting polymers stable at temperatures in excess of 100.degree. C., the polymer being basic polymer complexed with a strong acid or an acid polymer. The invention further relates to the use of such membranes in electrolytic cells and acid fuel cells. Particularly, the invention relates to the use of polybenzimidazole as a suitable polymer electrolyte membrane.
    Type: Grant
    Filed: November 1, 1994
    Date of Patent: June 11, 1996
    Assignee: Case Western Reserve University
    Inventors: Robert F. Savinell, Morton H. Litt
  • Patent number: 5523181
    Abstract: The polymer solid-electrolyte composition according to the present invention comprises a polymer solid electrolyte selected from the group consisting of perfluorocarbon sulfonic acid, polysulfones, perfluorocarbonic acid, styrene-divinylbenzene sulfonic acid cation-exchange resins and styrene-butadiene anion-exchange resins, and 0.01-50% by weight of fine particle silica and/or fibrous silica fiber relative to the weight of the polymer solid electrolyte.
    Type: Grant
    Filed: September 24, 1993
    Date of Patent: June 4, 1996
    Assignees: Masahiro Watanabe, Stonehart Associates, Inc.
    Inventors: Paul Stonehart, Masahiro Watanabe
  • Patent number: 5480518
    Abstract: The production of high purity oxygen and hydrogen gases can be accomplished utilizing an electrolysis assembly comprising an anode, a cathode, an ion exchange membrane disposed therebetween, an anode chamber, and a cathode chamber. This ion exchange membrane has been multiply impregnated with catalyst and therefore contains internal catalyst sites where hydrogen gas, which diffuses through the ion exchange membrane from the cathode chamber, and oxygen gas, which diffuses through the ion exchange membrane from the anode chamber, react to form water. Reacting the hydrogen and oxygen gases within the ion exchange membrane prevents these gases from contaminating the oxygen stream in the anode chamber and the hydrogen stream in the cathode chamber, respectively.
    Type: Grant
    Filed: May 27, 1994
    Date of Patent: January 2, 1996
    Assignee: United Technologies Corporation
    Inventors: Eric M. Shane, James F. McElroy
  • Patent number: 5474661
    Abstract: Methods, and various apparatus therefor, are disclosed for the electrolytic treatment of an acidic solution. Generally the method comprises: (a) providing an electrolytic cell, the cell comprising: (i) an anode chamber and an anode therein; (ii) a cathode chamber and a cathode therein; and (iii) a diaphragm. Usually the diaphragm is of a non-isotropic fibrous mat comprising 5-70 weight percent organic halocarbon polymer fiber in adherent combination with about 30-95 weight percent of finely divided inorganic particulate impacted into said fiber during fiber formation, the diaphragm having a weight per unit of surface area of about 3-12 kilograms per square meter. The method can continue by (b) introducing the acidic solution into the cell; (c) impressing a current on the anode and the cathode causing the migration of ions through the diaphragm; and (d) recovering a product of the electrolytic treatment from the anode chamber, or the cathode chamber, or from both chambers.
    Type: Grant
    Filed: March 9, 1995
    Date of Patent: December 12, 1995
    Assignee: Eltech Systems Corporation
    Inventors: Jeries I. Bishara, James R. Brannan
  • Patent number: 5470449
    Abstract: Microporous diaphragms adapted for wet-consolidation with composite cathodes for use in electrolytic cells, e.g., chlorine/soda electrolysis cells, comprise a sintered, fluoropolymer microconsolidated asbestos-free microporous fibrous sheet material, such sheet material including from 3% to 35% by weight of fluoropolymer binder, from 0% to 50% by weight of a uniformly distributed gel of an oxohydroxide of at least one metal of Groups IVA, IVB, VB and VIB of the Periodic Table or of the lanthanide or actinide series thereof, and from 20% to 95% by weight of a mixture of poly-tetrafluoroethylene (PTFE) fibers and inorganic fibers, such inorganic fibers constituting from 1% to 80% by weight of the mixture and such inorganic fibers including carbon, graphite or titanate fibers, or admixture thereof.
    Type: Grant
    Filed: July 14, 1994
    Date of Patent: November 28, 1995
    Assignee: Rhone-Poulenc Chimie
    Inventors: Jean Bachot, Pascal Stutzmann
  • Patent number: 5466354
    Abstract: Accumulated dimensional variations in fuel cells and electrolysis cell assemblies can reduce the efficiency of the assembly and provide leakage paths for fuel and oxidant. A metal compression pad comprised of a metal having an elastic strain of about 3% to about 40% at about 2,500 psig can compensate for component dimensional variations and improve inter-cell conductivity at pressures up to and exceeding about 10,000 psig.
    Type: Grant
    Filed: September 20, 1994
    Date of Patent: November 14, 1995
    Assignee: United Technologies Corporation
    Inventors: Andrei Leonida, Lawrence C. Moulthrop, Kurt M. Critz
  • Patent number: 5425865
    Abstract: Composite polymer membranes are disclosed comprising a first polymeric material which defines a porous matrix, and a second polymeric material which at least partially fills, and thereby blocks, the pores of the matrix, and in which preferably each of the first and second materials are crosslinked. The membrane preferably includes a layer of an ethylenically unsaturated carboxylic acid which is graft-polymerized with the first polymeric material of the porous matrix on one of its surfaces. Crosslinking has been found to improve the transport characteristics of species through the membrane, such as the barrier performance of the membrane towards species dissolved in solution.
    Type: Grant
    Filed: March 4, 1993
    Date of Patent: June 20, 1995
    Assignee: Scimated Limited
    Inventors: Raymond W. Singleton, John A. Cook, Kenneth Gargan
  • Patent number: 5419984
    Abstract: This invention is directed to the use of polysiloxane acrylates in solid electrolytes containing a solid polymeric matrix. The solid electrolytes are used in electrochemical cells for secondary batteries.
    Type: Grant
    Filed: December 16, 1993
    Date of Patent: May 30, 1995
    Assignee: Valence Technology Inc.
    Inventors: Benjamin Chaloner-Gill, M. Neal Golovin
  • Patent number: 5417832
    Abstract: The present invention describes a perfluorinated ionomer membrane having a improved transport characteristics. A surfactant species is added to a polymer mixture prior to film casting. The resulting membranes have a measurably altered membrane microstructure and improved transport characteristics over prior art membranes. The present invention describes the method of producing the improved membranes. The membranes of the present invention are useful in a number of separation processes, including the separation of NH.sub.3 from gaseous and liquid mixtures, in the production of NaOH and Cl.sub.2 gas from the electrolytic dissolution of NaCl, in the separation of toxic and radioactive metals from aqueous streams, and in solid polymer electrolyte H.sub.2 /O.sub.2 fuel cells.
    Type: Grant
    Filed: August 25, 1992
    Date of Patent: May 23, 1995
    Assignee: The University of Colorado Foundation, Inc.
    Inventors: John Pellegrino, Richard D. Noble, Robert Rabago, Carl Koval
  • Patent number: 5409588
    Abstract: A porous composite material for diaphragms for high-output electrochemical cells such as lithium cells. The material is a layered structure of fluoropolymer and polyolefin that provides a shut-down capability that safeguards against dangerous failure of the cell, such as a rupture or fire that may result from a short-circuit or other high-rate electric discharge.
    Type: Grant
    Filed: June 25, 1993
    Date of Patent: April 25, 1995
    Assignee: Japan Gore-Tex, Inc.
    Inventors: Naofumi Mushiake, Takayuki Wani, Hiroshi Kato, Takeshi Sagara, Fumihiro Sasaki
  • Patent number: 5397445
    Abstract: A method for producing an acid and/or an alkali metal hydroxide, from a neutral salt by electrodialysis employing a bipolar membrane and an anion exchange membrane and/or a cation exchange membrane, wherein as the anion exchange membrane, an anion exchange membrane made of a polymer having repeating units of the formula: ##STR1## wherein each of R.sub.1, R.sub.2 and R.sub.3 is a hydrogen atom or an alkyl group having up to two carbon atoms, and having an ion-exchange capacity of from 1 to 5 meq/g dry resin, is used.
    Type: Grant
    Filed: January 19, 1994
    Date of Patent: March 14, 1995
    Assignee: Asahi Glass Company Ltd.
    Inventors: Kazuo Umemura, Tsutomu Naganuma, Haruhisa Miyake
  • Patent number: 5389433
    Abstract: A battery separator composed of a microporous sheet product having first and second major surfaces and a thickness of less than about 50 mils, formed from a uniform mixture of a polysulfone polymer and a filler or polysulfone polymer and structure enhancing agent, said sheet product having a fibrous sheet embedded within said mixture and between the first and second major surfaces. The porosity of the sheet product is at least about 60 volume percent composed of pores such that the average pore diameter increases from each major surface toward the interior of the sheet product's thickness.
    Type: Grant
    Filed: April 1, 1993
    Date of Patent: February 14, 1995
    Assignee: W. R. Grace & Co.-Conn.
    Inventors: Victor S. C. Chang, Richard C. Hartwig, James K. Kung, Joseph T. Lundquist, Marc E. Parham, James A. Avtges, Anthony J. Laccetti
  • Patent number: 5384019
    Abstract: An ion exchange membrane reinforced with leno weave yarn system having sacrificial fibers paired with resistant fibers in the warp of the fabric, and an electrolysis process using the membrane are disclosed.
    Type: Grant
    Filed: October 29, 1993
    Date of Patent: January 24, 1995
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: James T. Keating, Everett I. Baucom, James M. Batman
  • Patent number: 5380413
    Abstract: Process for the manufacture of a bipolar membrane, according to which a cationic membrane is treated with a compound of a polyvalent metal and with an aqueous alkali metal hydroxide solution comprising lithium hydroxide and is then joined side by side to an anionic membrane. The bipolar membrane finds an application in the manufacture of aqueous sodium hydroxide solutions by electrodialysis.No figure.
    Type: Grant
    Filed: March 31, 1994
    Date of Patent: January 10, 1995
    Assignee: Solvay (Societe Anonyme)
    Inventors: Francesco Posar, Mauro Ricciardi
  • Patent number: 5380423
    Abstract: The invention relates to a membrane that is selective for anions, particularly phosphate, comprising an ionophore based on a uranyl complex with the annexed general formula, whereinA, B, C, D=RA+B+C+D=(C.sub.5 -C.sub.7) aryl, (C.sub.5 -C.sub.7) cycloalkyl,(C.sub.1 -C.sub.30) alkyl (C.sub.5 -C.sub.10) aryl, (C.sub.1 -C.sub.30) alkyl (C.sub.5 -C.sub.10) cycloalkyl,E+E', G+G'=aryl, such as phenyl and naphthyl, or aryl substituted with a substituent (C.sub.1 -C.sub.30) alkoxy, or aryl substituted with the individual substituent or the substituent joined by ring closure K and/or K--CONH--L, whereinK, L=H --R--(CH.sub.2).sub.m --, --R--(CH.sub.2).sub.m --R, --X--(CH.sub.2).sub.m --, --X(CH.sub.2).sub.m --R, --X--(CH.sub.2).sub.m --X, --X(CH.sub.2).sub.m --X--R, --RX(CH.sub.2).sub.m --, --RX(CH.sub.2).sub.m --XR, --X--(R--X).sub.n --,wherein X=O, S; m= 0-10 and n= 0-10R=(C.sub.1 -C.sub.30) alkyl, (C.sub.5 -C.sub.10) aryl, (C.sub.5 -C.sub.10) cycloalkyl, (C.sub.1 -C.sub.30) alkyl (C.sub.5 -C.sub.10) aryl, (C.sub.
    Type: Grant
    Filed: October 15, 1993
    Date of Patent: January 10, 1995
    Assignee: Priva Agro Holding B.V.
    Inventors: David N. Reinhoudt, Johannes F. J. Engbersen, Willem Verboom, Dimitri Rudkevich, Walter P. R. V. Stauthamer
  • Patent number: 5366606
    Abstract: The present invention provides an electrolytic gas generator for generating fluorine and other chemicals and more particularly, to a more efficient electrolyzer having reduced resistance between the cathode and anode and which prevents the migration of gas between the anode compartment and the cathode compartment.
    Type: Grant
    Filed: May 17, 1993
    Date of Patent: November 22, 1994
    Assignee: Florida Scientific Laboratories Inc.
    Inventor: Gregorio Tarancon
  • Patent number: 5358620
    Abstract: This invention is directed to novel solid electrolytes containing a solid polymeric matrix having incorporated therein allylic ester or carbonate. The solid electrolytes are used in electrochemical cells.
    Type: Grant
    Filed: October 13, 1993
    Date of Patent: October 25, 1994
    Assignee: Valence Technology, Inc.
    Inventors: M. Neal Golovin, Benjamin M. Chaloner-Gill
  • Patent number: 5346924
    Abstract: A novel, heterogeneous ion exchange membrane, methods for making such a membrane, and devices containing such a membrane are disclosed. Such membranes comprise linear low or linear medium density polyethylene or high molecular weight high density polyethylene as a binder and can incorporate a wide variety of ion exchange resin materials. The membranes can be fabricated using extrusion or other melt processing procedures to produce a product, which upon conditioning in water, exhibits properties adapted for use in numerous applications.
    Type: Grant
    Filed: September 23, 1992
    Date of Patent: September 13, 1994
    Assignee: IP Holding Company
    Inventor: Anthony Giuffrida
  • Patent number: 5342494
    Abstract: The production of high purity oxygen and hydrogen gases can be accomplished utilizing an electrolysis assembly comprising an anode, a cathode, an ion exchange membrane disposed therebetween, an anode chamber, and a cathode chamber. This ion exchange membrane has been multiply impregnated with catalyst and therefore contains internal catalyst sites where hydrogen gas, which diffuses through the ion exchange membrane from the cathode chamber, and oxygen gas, which diffuses through the ion exchange membrane from the anode chamber, react to form water. Reacting the hydrogen and oxygen gases within the ion exchange membrane prevents these gases from contaminating the oxygen stream in the anode chamber and the hydrogen stream in the cathode chamber, respectively.
    Type: Grant
    Filed: March 5, 1993
    Date of Patent: August 30, 1994
    Assignee: United Technologies Corporation
    Inventors: Eric M. Shane, James F. McElroy
  • Patent number: 5330626
    Abstract: The present invention is a process for modifying a fluorinated ion exchange membrane by irradiation of the membrane with a sufficient dose of non-spark-producing radiation to increase water absorption and/or ionic conductivity of the membrane. The membranes are particularly useful in fuel cells and chloralkali cells.
    Type: Grant
    Filed: February 16, 1993
    Date of Patent: July 19, 1994
    Assignee: E. I. du Pont de Nemours and Company
    Inventor: Shoibal Banerjee
  • Patent number: 5324565
    Abstract: Accumulated dimensional variations in fuel cells and electrolysis cell assemblies can reduce the efficiency of the assembly and provide leakage paths for fuel and oxidant. An elastomeric compression pad comprised of an oil adsorbent sheet surrounding an elastomeric material with expansion pathways and electrical pathways, that utilize a conductive powder and elastomeric binder compensates for component dimensional variations, improves inter-cell conductivity, and allows high pressure operation up to about 3,000 psig.
    Type: Grant
    Filed: December 17, 1992
    Date of Patent: June 28, 1994
    Assignee: United Technologies Corporation
    Inventors: Andrei Leonida, Lawrence C. Moulthrop
  • Patent number: 5320867
    Abstract: Microporous diaphragms adapted for wet-consolidation with composite cathodes for use in electrolytic cells, e.g., chlorine/soda electrolysis cells, comprise a sintered, fluoropolymer microconsolidated asbestos-based microporous fibrous sheet material, such sheet material including from 3% to 35% by weight of fluoropolymer binder, from 1% to 50% by weight of a uniformly distributed gel of an oxohydroxide of at least one metal of Groups IVA, IVB, VB and VIB of the Periodic Table or of the lanthanide or actinide series thereof, and from 20% to 95% by weight of fibers, at least 1% by weight of such fibers being asbestos fibers.
    Type: Grant
    Filed: December 4, 1991
    Date of Patent: June 14, 1994
    Assignee: Rhone-Poulenc Chimie
    Inventors: Jean Bachot, Pascal Stutzmann, Jean-Maurice Perineau
  • Patent number: 5320716
    Abstract: Thin polymeric films, coatings and ionic conductors by cross-linking a polymer matrix, such as a polyethyleneimine, polyetheramine, polyallylamine or polyacrlyamide, with a fluorocarbon containing epoxide or anhydride. The compositions are of high integrity and posses properties, such as insulation, ion conduction, anticorrosion, antifouling and self-adhesion. Specific compositions absorb and release acidic gases and liquids.
    Type: Grant
    Filed: March 16, 1992
    Date of Patent: June 14, 1994
    Inventor: Masud Akhtar
  • Patent number: 5316629
    Abstract: A process is disclosed for maintaining or increasing electrolyte flow rate through a microporous diaphragm in an electrochemical cell for the production of hydrogen peroxide by maintaining in the electrolyte a sufficient concentration of a stabilizing agent. Flow rate is maintained or increased by complexing transition metal ions or compounds with the stabilizing agent.
    Type: Grant
    Filed: September 20, 1991
    Date of Patent: May 31, 1994
    Assignee: H-D Tech Inc.
    Inventors: Arthur L. Clifford, Derek J. Rogers, Dennis Dong
  • Patent number: 5310765
    Abstract: A process is provided for hydrolysis of fluorinated ion exchange membranes. The membrane is contacted with an aqueous solution containing a hydrocarbon having ether, epoxy or ketone linkages and an alcohol group, preferably 1-methoxy 2-propanol, for a period of time sufficient to perform the hydrolysis of the precursor groups. The membrane is useful in a fuel cell or in an electrolytic cell, particularly a chloralkali cell.
    Type: Grant
    Filed: March 3, 1993
    Date of Patent: May 10, 1994
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Shoibal Banerjee, Walther G. Grot
  • Patent number: 5288384
    Abstract: A diaphragm for electrolyzing alkali metal chloride solutions is provided which is one or more layers of a porous support, coated with a perfluoro ion exchange polymer and then wet with a wetting solution which has a surface tension of 22 to 45 dynes/cm. The wetting solution is preferably an aqueous alcohol and most preferably aqueous 3-6.5% butanol. The wetting solution assists in initial water penetration into the pores of the diaphragm, rendering the diaphragm hydrophilic so as to resist gas locking and premature shutdown of the electrolytic cell.
    Type: Grant
    Filed: April 15, 1993
    Date of Patent: February 22, 1994
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Shoibal Banerjee
  • Patent number: 5288385
    Abstract: A supported, mechanically stable bipolar membrane for electrodialysis having a cation-exchange layer on one side and an anion-exchange layer on the other side of a single sheet of woven fabric. The cation exchange layer is heterogeneous, the anion exchange layer is homogeneous and the two are interlocked. A process of making such bipolar membranes is described. The bipolar membrane may be fabricated into electrodialysis cells in which two membranes are joined along their edges.
    Type: Grant
    Filed: March 17, 1992
    Date of Patent: February 22, 1994
    Assignee: Yeda Research and Development Co., Ltd.
    Inventors: Ora Kedem, Abraham Warshawsky
  • Patent number: 5273628
    Abstract: Mixed oxygen ion and electronic conducting bismuth oxide based ceramic materials having high ambipolar activity which can be fabricated into thin membranes for high efficiency oxygen separation from air at intermediate temperatures. The ceramic materials may be homogeneous microstructures in the form of solid solutions or compounds or may be composite non-homogeneous microstructures of a separate substantially continuous oxygen ion conductive phase and a substantially continuous electronic conductive phase.
    Type: Grant
    Filed: May 11, 1992
    Date of Patent: December 28, 1993
    Assignee: Gas Research Institute
    Inventors: Meilin Liu, Ashok V. Joshi, Yousheng Shen, Kevin Krist
  • Patent number: 5271813
    Abstract: An electrolyzer is provided for electrolyzing water into its constituent elements, namely oxygen and hydrogen gas. The electrolyzer includes a vessel in which a sulfonated solid polymer electrolyte is situated. The sulfonated solid polymer electrolyte is selected from a group including sulfonated polyetheretherketone (SPEEK), sulfonated polyethersulfone (SPES), sulfonated polybenzimidazole (SPBI), sulfonated polyphenylquinoxaline (SPPQ) and sulfonated fluorinated polyimide (SFPI). The electrolyzer also includes anode and cathode electrodes situated on the electrolyte. A direct current (DC) power supply is coupled to said anode and cathode electrodes to drive the reaction. A heater heats the electrolyte and a water supply is connected to one of said cathode and anode electrodes. The resultant oxygen and hydrogen are collected at the respective electrodes. The solid polymer electrolyte desirably operates with relatively high ionic conductivity at high temperatures without loss of structural integrity.
    Type: Grant
    Filed: March 29, 1993
    Date of Patent: December 21, 1993
    Assignee: University of Central Florida
    Inventor: Clovis A. Linkous
  • Patent number: 5266350
    Abstract: Materials for treating and/or repairing electrolytic cell separators, especially diaphragms for chlor-alkali cells, including processes for making such treating materials and processes for using such materials to treat and/or repair an electrolytic cell separator or chlor-alkali diaphragm.
    Type: Grant
    Filed: July 14, 1992
    Date of Patent: November 30, 1993
    Assignee: The Dow Chemical Company
    Inventors: Neal A. Grob, John P. McGraw, Jr.
  • Patent number: 5264100
    Abstract: A fluorine-containing cation exchange membrane for electrolysis, which comprises a first layer of a fluorine-containing polymer having cation exchange groups and reinforced with a porous base material and a second layer of a fluorine-containing polymer having carboxylic acid groups, present on the cathode side of the first layer, wherein at least 1/2 of the thickness of the porous base material protrudes from the first layer towards the anode side, the protrusions of the porous base material are covered with a coating layer of a fluorine-containing polymer having cation exchange groups so that the coating layer is integrated with the first layer, and the anode side surface of the coating layer has a roughness corresponding to the surface contour of the porous base material.
    Type: Grant
    Filed: March 24, 1992
    Date of Patent: November 23, 1993
    Assignee: Asahi Glass Company Ltd.
    Inventors: Tetsuji Shimohira, Yoshiaki Higuchi, Yoshihiko Saitoh
  • Patent number: 5264093
    Abstract: The present invention is a process for modifying a fluorinated cation exchange membrane by irradiation of the membrane in its salt form with a sufficient dose of non-spark-producing radiation to increase the current efficiency in the use of the membrane for electrolyzing sodium chloride solution to produce high concentrations of caustic.
    Type: Grant
    Filed: April 30, 1992
    Date of Patent: November 23, 1993
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Shoibal Banerjee
  • Patent number: 5264090
    Abstract: A method for the electrolysis of an alkali metal chloride in an electrolytic cell is disclosed, in which use is made of a cation exchange membrane comprising a carboxylate-containing fluorocarbon polymer layer disposed on a cathode compartment side and provided on its surface with an inorganic coating, and a sulfonate and/or carboxylate-containing fluorocarbon polymer layer disposed on an anode compartment side and having a water content of from 3 to 10% by weight. By this method, an alkali metal hydroxide, e.g., sodium hydroxide, can be directly produced in a concentration as high as 45-55 % by weight from a saline solution having an alkali metal chloride concentration as low as from 3.0 to 3.5N with reduced energy consumption, stably for a prolonged period of time.
    Type: Grant
    Filed: October 4, 1991
    Date of Patent: November 23, 1993
    Assignee: Asahi Kasei Kogyo Kabushiki Kaisha
    Inventors: Tatsuo Hiyoshi, Akio Kashiwada
  • Patent number: 5258106
    Abstract: Alkali metal sulfates are electrolyzed to more concentrated solutions of alkali metal hydroxide and sulfuric acid by using a three-compartment electrodialysis cell at temperatures of .gtoreq.70.degree. to .gtoreq.150.degree. C. and current densities of from 0.5 to 15 kA/m.sup.2 using an anion exchange membrane whose polymeric ion exchange matrix comprises a styrene/divinylbenzene copolymer containing very strongly basic quaternary ammonium groups and a hydronium ion blocker, on whose central compartment side is an ion exchange layer or membrane containing tertiary or secondary amino groups.
    Type: Grant
    Filed: March 20, 1991
    Date of Patent: November 2, 1993
    Assignee: BASF Aktiengesellschaft
    Inventors: Wolfgang Habermann, Werner Bochnitschek, Johann Fritzmann, Peter Hammes, Theo Proll, Walter Weisbrodt
  • Patent number: 5254233
    Abstract: A monopolar ion exchange membrane electrolytic cell assembly comprising a plurality of unit electrolytic cells connected electritically in parallel to one another, each formed by clamping an anode compartment frame and a cathode compartment frame with an ion exchange membrane interposed therebetween, the anode and cathode compartment frames each having a feeding and discharging system for an electrolyte and a discharging system for generated gas, wherein:(a) an anode is made of a foraminous plate fixed to the anode compartment frame so that it is close to or in contact with the ion exchange membrane, and electricity is supplied to the foraminous plate via power supply rods and/or power supply ribs from a power source located outside the cell,(b) a cathode is made of flexible foraminous metal plate having good conductivity with an electric resistance at 20.degree. C. of not higher than 10 .mu..OMEGA..
    Type: Grant
    Filed: July 10, 1992
    Date of Patent: October 19, 1993
    Assignee: Asahi Glass Company Ltd.
    Inventors: Makoto Nakao, Hidenori Shibata, Takeo Aikawa, Takahiro Uchibori, Hiroki Yano
  • Patent number: 5252193
    Abstract: A reinforced fluorinated cation exchange membrane for the electrolysis of alkali halide solutions is reinforced with fabric containing both sacrificial and permanent fibers in which the anolyte surface of the membrane is abraded to expose some of the reinforcement crossover points. A process for abrading the membrane and an electrolytic cell using the membrane are also claimed. The preferred method of abrasion is continuous sanding. The abraded membrane improves the current efficiency of the electrolytic cell.
    Type: Grant
    Filed: November 4, 1991
    Date of Patent: October 12, 1993
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: John D. Powers
  • Patent number: 5246559
    Abstract: A method, and apparatus therefor, for the electrolytic treatment of an acidic solution which comprises: (a) providing an electrolytic cell, the cell comprising: (i) an anode chamber and an anode therein; (ii) a cathode chamber and a cathode therein; (iii) a diaphragm of a non-isotropic fibrous mat comprising 5-70 weight percent organic halocarbon polymer fiber in adherent combination with about 30-95 weight percent of finely divided inorganic particulate impacted into said fiber during fiber formation, the diaphragm having a weight per unit of surface area of about 3-12 kilograms per square meter; (b) introducing the acidic solution into the cell; (c) applying a DC voltage between the anode and the cathode causing the migration of ions through the diaphragm; and (d) recovering a product of the electrolytic treatment from the anode chamber, or the cathode chamber, or from both chambers.
    Type: Grant
    Filed: November 29, 1991
    Date of Patent: September 21, 1993
    Assignee: ELTECH Systems Corporation
    Inventors: Jeries I. Bishara, James R. Brannan
  • Patent number: 5238548
    Abstract: An ionophore according to the general formula I wherein the substituents are chosen such that the ionophore is either also polymerized in the matrix of a membrane selective for metal ions or interwoven therewith. Thus obtained is a membrane having a long useful life for use in diverse sensors such as ISFET, ion-selective electrode, and the like.
    Type: Grant
    Filed: May 18, 1992
    Date of Patent: August 24, 1993
    Assignee: Priva Agro Holding B.V.
    Inventors: Peter D. van der Wal, Udo H. Verkerk, Gerardus W. N. Honig, Hermanus A. J. Holterman, Jan R. Haak, David N. Reinhoudt
  • Patent number: 5227040
    Abstract: A low electrical resistance bipolar membrane formed by the conjoining of treated anion and cation exchange membranes is disclosed. The treatment comprises contacting the membranes with an aqueous solution of at least one cation prior to conjoining and contacting at least one face of the membranes with an aqueous alkaline solution.A process for the preparation of acid and alkali using these bipolar membranes is also disclosed.
    Type: Grant
    Filed: October 25, 1991
    Date of Patent: July 13, 1993
    Assignee: Unisearch Limited
    Inventor: Raymond G. Simons
  • Patent number: 5221455
    Abstract: Disclosed is a bipolar membrane comprising a cation-exchange membrane in which a cation-exchange group present at least at its adhered surface has been ion-exchanged with a heavy metal ion, which is adhered closely to an anion-exchange membrane at a peel strength of not less than 0.2 kg f/25 mm, and having a water-splitting current efficiency of not less than 80% and a water-splitting membrane potential of not more than 2.0 V.
    Type: Grant
    Filed: May 31, 1991
    Date of Patent: June 22, 1993
    Assignee: Tokuyama Soda Kabushiki Kaisha
    Inventors: Fumio Hanada, Koki Hirayama, Nobuhiko Ohmura, Shinsuke Tanaka
  • Patent number: 5211827
    Abstract: An electrochemical cell employs an ionic semiconductor material as a separator between an anolyte and a catholyte. Ionic semiconductor material includes 10 to approximately 50 percent by weight of a hydrogel which is dispersed within an inert nonporous matrix material to form a composite wherein the quantity of water that can be absorbed by the composite does not substantially exceed the weight of the composite.
    Type: Grant
    Filed: August 5, 1991
    Date of Patent: May 18, 1993
    Assignee: T and G Corporation
    Inventor: Robert L. Peck