Abstract: Porous and electrolyte permeable composite diaphragms for electrolysis cells comprising a chemically inert, fibrous porous matrix or substrate impregnated with a copolymer of divinylbenzene and at least one member of the group consisting of 2-vinylpyridine and 4-vinylpyridine, method of electrolysis of an electrolyte using the said diaphragms and an electrolysis cell containing said diaphragms.

Abstract: A diaphragm for use in the electrolysis of alkali metal chloride brines in electrolytic diaphragm cells is comprised of a support fabric impregnated with a non-fibrilic active component containing silica where the porous diaphragm has a permeability to alkali metal chloride brines of from about 100 to about 300 milliliters per minute per square meter of diaphragm at a head level difference in the cell of from about 0.1 to about 20 inches of the alkali metal chloride brines. The active component containing silica is employed in concentrations of from about 10 to about 75 milligrams per square centimeter of support fabric.Suitable silica-containing materials include sand, colloidal silica, alkali metal silicates, alkaline earth metal silicates, aluminum silicates, as well as minerals such as sepiolites, meerschaums, attapulgites, montmorillonites and bentonites.Support fabrics include, for example, felt fabrics produced from thermoplastics such as polyolefins or polyarylene sulfides.

Abstract: An especially efficient and durable electrolytic cell is provided by utilizing a combined cathode and diaphragm unit wherein the cathode is made by spray coating a ferrous metal substrate with a powder metal having lower hydrogen overvoltage than said substrate to form a protected cathode surface having a larger surface area than the substrate, and vacuum depositing a polymer impregnated asbestos fiber diaphragm onto a spray coated surface of the cathode to form a fibrous diaphragm thereon. Preferably, the cathode surface is made with nickel and the polymer impregnated asbestos diaphragm contains from about 10 to about 30 percent based on the weight of asbestos of an organic cementing agent such as a fluorohydrocarbon polymer.

Abstract: Improved asbestos-containing diaphragms and mats are prepared by bonding the asbestos fibers to one another by pyrolyzing an organic titanate in situ.

Abstract: Disclosed is an electrolytic cell having electrode units of opposite polarity where each of the electrode units have fingered electrodes extending outwardly therefrom toward the electrode unit of opposite polarity. In this way, the electrodes are interleaved between electrodes of opposite polarity. At least one of the electrode units has a base plate with fingered electrodes mechanically and electrically connected thereto. The fingered electrodes bear a synthetic separator such as a microporous diaphragm or a permionic membrane thereon with lap at the base. The electrolytic cell is characterized by a fingered, interleaved electrode of the electrode unit of opposite polarity compressively bearing upon the lap, whereby to provide an electrolyte-tight seal.

Abstract: Magnesium compounds are added to chlor-alkali cell asbestos diaphragms, either initially or after some use, to improve electrical operating characteristics.

Abstract: A membrane assembly, useful as a membrane in electrodialytic and electrolytic cells, is made by holding together a plurality of thin layers of membrane material under pressure and with boundary layers of liquid covering their major surfaces. Such membrane assemblies allow the passage therethrough of ions when an electric potential difference is impressed across the membrane assembly but effectively bar the passage of water and gases. They also bar or limit ionic and salt mass transfer in the absence of such a potential difference (during non-use of the cell). They make excellent long lasting cell components, capable of being manufactured simply and economically from any of a variety of membrane materials to produce membranes of desired properties.

Abstract: A securing device is disclosed which retains membranes in electrolytic cells during assembly and disassembly thereof and which allows safe, effective storage during disassembly of the cell.

Abstract: Disclosed is a diaphragm having a porous, hydrophobic fluorocarbon matrix, an intermediate layer or film of a hydrophilic fluorocarbon resin on the surfaces of the matrix, and a hydrous oxide of zirconium contained in the void volumes of the matrix. The layer of the hydrous oxide of zirconium may also contain MgO.

Abstract: Disclosed is a method of preparing a hydrous zirconium oxide diaphragm by treating a porous matrix with ZrOCl.sub.2 and hydrolyzing the ZrOCl.sub.2 to ZrO.sub.2 with NH.sub.3. The disclosed method contemplates leaching out the NH.sub.4 Cl, dehydrating the substrate, and sequentially building up the ZrO.sub.2.

Abstract: Disclosed is a diaphragm having a porous matrix, e.g., a polymeric or asbestos matrix with a layer of magnesium oxide and a hydrous oxide of zirconium therein.

Abstract: Asbestos diaphragms in commercial cells for the electrolysis of brines are treated with a dispersion of an alkaline earth metal-containing silicate. Deposition of the dispersion within the diaphragm results in a decrease in hydrogen concentration in chlorine gas produced as well as an increase in current efficiency.

Abstract: A diaphragm for use in the electrolysis of alkali metal chloride solutions in electrolytic diaphragm cells is comprised of a mixture of an electrically non-conducting, non-swelling support material impregnated with a mixture of sand and a synthetic thermoplastic polymeric binding agent. The diaphragms may include a lubricant, a wetting agent or an additive such as alumina, inorganic phosphates, lithium salts, lime, magnesia or inorganic magnesium salts. The diaphragms of the present invention have increased chemical and dimensional stability, a long operational life and are non-polluting.

Abstract: A diaphragm for use in the electrolysis of alkali metal chloride solutions in electrolytic diaphragm cells is comprised of a mixture of sand and a polyolefin thermoplastic polymeric binding agent. The diaphragms may include a support material and an additive such as a lubricant. The diaphragms of the present invention have increased stability, a long operational life and are non-polluting.

Abstract: An apparatus to electrolytically produce multivalent metals, such as titanium, from compounds thereof. The apparatus includes a suitable containing body with an anode and a cathode in compartments therein spaced apart by a foraminous diaphragm with at least a surface portion consisting essentially of nickel or, preferably, cobalt. The diaphragm has a diaphragm coefficient of greater than zero to about 0.5 when the coefficient of flow is about 0.1 to about 25. A multivalent metal compound feed means is combined with the cathode compartment to supply a multivalent metal compound to a molten salt electrolyte in the cathode compartment. The apparatus is sealed from the atmosphere to avoid contamination of the bath and metal product with certain atmospheric gases. Means of providing sufficient electrical and thermal energy to operate the cell are provided.

Abstract: A diaphragm for use in the electrolysis of alkali metal chloride solutions in electrolytic diaphragm cells is comprised of a mixture of sand and a thermoplastic polymeric binding agent comprised of a mixture of a polyarylene sulfide and a polyolefin compound. The diaphragms may include a support material and an additive such as a lubricant. The diaphragms of the present invention have increased stability, a long operational life and are non-polluting.

Abstract: A method to electrolytically produce metallic titanium from compounds thereof. The method includes first inserting a foraminous diaphragm with at least a surface portion consisting essentially of nickel or, preferably, cobalt into an electrolytic cell. The diaphragm has a diaphragm coefficient of greater than zero to about 0.5 when the coefficient of flow is about 0.1 to about 25 in an electrolytic cell. The cell further includes an anode spaced apart by the diaphragm from a cathode and a titanium compound feed means. A feed means is combined with the cathode compartment to supply a titanium compound to a molten salt electrolyte in the cathode compartment. The apparatus is preferably sealed from the atmosphere to avoid contamination of the bath and metal product with certain atmospheric gases. An ionizable titanium compound is subsequently introduced into the electrolyte and an electromotive force impressed between the anode and the cathode to thereby deposit metallic titanium on the cathode.

Abstract: A method of purifying a galvanizing and/or metal cleaning plant pickle liquor to enable repetitive re-use of the acid which includes the steps of placing a cathode and an anode in the spent acid (pickle liquor) and passing a DC current therethrough. The cathode and anode are separated in the pickle liquor solution by a permeable diaphragm which permits transfer therethrough of the metal ions and the acid anions. Metal molecules in the liquor such as iron, zinc, etc., are recovered upon their adherence to the cathode. The recovery is about 80 to 90 percent of the total metal ion content on that side of the diaphragm. The iron in solution is removed from that side of the tank and it is transferred to a precipitator tank. There, a neutralizing base is added to precipitate the remaining iron typically as a ferric hydroxide out of the tank.

Abstract: A porous layer is provided on one or both surfaces of a mass-transfer membrane to enhance or modify the passage of ions. The membrane may be a film of any of a variety of polymeric materials, and the porous layer may be a surface layer on the membrane or a separate porous structure placed in contact therewith. The porous layer or layers render certain normally ion-impermeable polymeric films capable of passing ions in an electrodialysis-type system.

Abstract: Electrolysis of alkali metal chloride solutions to produce chlorine and alkali metal hydroxides is accomplished in a cell comprising an anode compartment, a cathode compartment and an anode separator which divides the anode compartment from the cathode compartment. The anode separator is comprised of a porous plate of a valve metal having an electrochemically active coating on the face, and an electrochemically non-active coating on the back and a portion of the interior. The electrochemically non-active barrier layer may include resinous materials, for example, polyarylene compounds or polyolefin compounds.The anode separator provides improved gas separation properties, eliminates the need for a separate diaphragm or membrane and enables the cell to operate with reduced power requirements.

Abstract: Novel two layer ceramic membranes for electrolysis cells comprising on the anodic side a layer of at least one oxide selected from the group consisting of Sb.sub.2 O.sub.5, Bi.sub.2 O.sub.5, MoO.sub.3, WO.sub.3 and V.sub.2 O.sub.5 and on the cathodic side a layer of at least one oxide selected from the group consisting of ZrO.sub.2, Nb.sub.2 O.sub.5, Ta.sub.2 O.sub.5 and TiO.sub.2, electrodes provided with a two layer ceramic membrane applied thereto, an electrolysis cell provided with a two layer ceramic oxide membrane and an electrolysis process wherein a two layer ceramic membrane is in the electrodic gap.

Abstract: An electrolytic method for making tin (II) sulfate wherein tin is anodically dissolved in a sulfuric acid solution and wherein the anode space is separated from the cathode space by a diaphragm, the diaphragm being composed of an inorganic, ceramic material which has been densified by sintering at above 1,000.degree. C.As a result of this process, tin (II) sulfate solutions can be obtained which have a very low content of tin (IV) compounds and from which a highly pure bivalent tin sulfate can be recovered.

Abstract: A method to electrolytically produce metallic titanium from compounds thereof. The method includes first positioning a foraminous metallic diaphragm with a diaphragm coefficient of greater than zero to about 0.5 when the coefficient of flow is about 0.1 to about 25 in an electrolytic cell. The cell further includes an anode spaced apart from a cathode and a titanium compound feed means by the diaphragm. A feed means is combined with the cathode compartment to supply a titanium compound to a molten salt electrolyte in the cathode compartment. The apparatus is preferably sealed from the atmosphere to avoid contamination of the bath and metal product with certain atmospheric gases. An ionizable titanium compound is subsequently introduced into the electrolyte and an electromotive force impressed between the anode and the cathode to thereby deposite metallic titanium on the cathode.

Abstract: An apparatus to electrolytically produce multivalent metals, such as titanium, from compounds thereof. The apparatus includes a suitable containing body with an anode and a cathode in compartments therein spaced apart by a foraminous metallic diaphragm. The diaphragm has a diaphragm coefficient of greater than zero to about 0.5 when the coefficient of flow is about 0.1 to about 25. A multivalent metal compound feed means is combined with the cathode compartment to supply a multivalent metal compound to a molten salt electrolyte in the cathode compartment. The apparatus is sealed from the atmosphere to avoid contamination of the bath and metal product with certain atmospheric gases. Means of providing sufficient electrical and thermal energy to operate the cell are provided.

Abstract: An electrode-separator combination unit for use in an electrolytic cell having planar interleaved electrodes and a method of assembling such a unit. Electrodes are individually enclosed in a closed envelope of separator material to form individual electrolyte chambers. The separator can be perforated and electrical conductors, fluid supply conduits and fluid outlet conduits can be sealingly passed through the perforations to allow supply of raw materials to the enclosed electrodes and to allow removal of products therefrom.

Abstract: The invention provides an electrode for use in an electrochemical reactor. The electrode comprising a plurality of carbon fibers in close proximity to one another, each of the fibers being in electrical contact with at least several of the other carbon fibers for transmitting an electrical potential substantially throughout the electrode when the electrode is in use in the reactor.

Abstract: An electrodialysis cell intended to be used for the electrolytic rejuvenation of ferricyanide bleach bath into ferricyanide comprises a vessel which is made of carbon and which serves as anode, and a cathode, the space defined by both electrodes being separated by a cationic permeable membrane which is a wall made of asbestos cement which has been treated with a strong acid to remove a substantial part of the cement. The elements of the cell preferably have a cylindrical structure and are concentrically arranged with respect to each other.

Abstract: Improved asbestos diaphragms for use in electrolytic chlor-alkali cells are prepared by using polymeric fluorocarbons as binders for mixtures of chyrsotile asbestos and crocidolite asbestos.

Abstract: An electrical method to determine the suitability of a diaphragm for use in an electrolytic cell. The method comprises inserting the diaphragm between a primary anode and a primary cathode immersed in an electrolyte and then impressing a known direct current electromotive force between the electrodes. The change in electrical properties across the electrolyte resulting from insertion of the diaphragm is determined. Such change is indicative of the suitability of the diaphragm for use in an electrolytic cell and can be a measure of diaphragm uniformity.

Abstract: A diaphragm for use in the electrolysis of alkali metal chloride solutions in elecrolytic diaphragm cells is comprised of a mixture of sand and a thermoplastic polymeric binding agent. The diaphragms may include a support material and an additive such as a lubricant. The diaphragms of the present invention have increased stability, a long operational life and are non-polluting.

Abstract: A porous anode separator for an electrolytic cell for the electrolysis of alkali metal chloride solutions comprises a porous valve metal plate having an electrochemically active coating on the face and a barrier layer on the back and on a portion of the interior. The barrier layer comprises a mixture of a valve metal oxide with a ceramic oxide. Suitable ceramic oxides include those of silicon, aluminum, magnesium, and calcium. The electrochemically active coating comprises a platinum group metal or metal oxide. The porous anodes provide improved gas separation and permit a substantial reduction in the amount of platinum group metal required for the electrochemically active coating.

Abstract: Disclosed is a proton permselective solid-state member which is formed of a heteropoly acid represented by the generic formula, H.sub.m [X.sub.x.sup.. Y.sub.y.sup.. O.sub.z ].sup.. nH.sub.2 O, or a salt thereof. Said permselective member can be used as an electrolyte in the fuel cell and as a permselective membrane in the hydrogen gas refining system.

Abstract: Disclosed is a method of preparing an asbestos diaphragm where alkali metal ions are provided from an aqueous alkaline solution within the fibrous asbestos diaphragm, the diaphragm is heated to form an alkali metal silicate layer on the asbestos fibers, and thereafter contacted with anolyte liquor.

Abstract: A high electrodensity chloro-alkali electrolytic diaphragm cell, wherein the diaphragm comprises a layer mixture of asbestos fibers and from 1 to 30 percent by weight of carbon fibers.

Abstract: The diaphragm of a chlor-alkali cell has its useful life prolonged by the unplugging thereof. Unplugging is achieved by shifting the pH gradient in the diaphragm toward the catholyte side. Simultaneously with the shifting of the pH gradient, chelates are formed in the anolyte solution from .alpha.-hydroxyketones and .alpha.-hydroxyaldehydes.

Abstract: Lithium haloboracites of the formula Li.sub.4 B.sub.7 O.sub.12 X where X is Cl, Br, I or a mixture thereof are useful as solid electrolytes for galvanic cells. Preferred lithium haloboracites are those in which X is a mixture of Br and Cl where Br is 20 to 50 mole percent of X.

Abstract: A diaphragm is disclosed for electrolytic cells, for example, chlor-alkali cells. The diaphragm is characterized in that it has been treated with a water-soluble silicate on the anolyte side. Also disclosed is an electrolytic cell process using such a diaphragm, and a method for preparing such a diaphragm.

Abstract: An improved method and apparatus for the electrolysis of ionizable chemical compounds is disclosed including specifically a process for the production of chlorine and caustic soda containing low concentrations of sodium chloride by the electrolysis of brine which comprises electrolyzing brine solutions in a two compartment cell equipped with a cathode and an anode separated by permselective barrier formed by sandwiching together two or more membranes consisting essentially of a hydrolyzed copolymer of tetrafluoroethylene and a sulfonated perfluorovinyl ether having the formulaFSO.sub.2 CF.sub.2 CF.sub.2 OCF(CF.sub.3)CF.sub.2 OCF=CF.sub.2said copolymer having an equivalent weight of from about 900 to about 1600. By the use of a multilayer membrane sandwich as the barrier the caustic current efficiency of the process is increased over that obtained when a single layer membrane is used as the barrier separating the cathode and anode.

Abstract: Disclosed is a method of preparing an asbestos diaphragm where alkali metal ions are provided within the fibrous asbestos diaphragm, the diaphragm is heated to form an alkali metal silicate layer on the asbestos fibers, and thereafter a further layer of asbestos is deposited on the diaphragm.