Abstract: A relatively-massive dual porosity gas electrode particularly well suited and adapted for utilization as a vertically-disposed oxygen gas-bearing electrochemically reducing cathode in electrolytic cells wherein, for efficient and practical, commercially-large-scale-output operations, there are required to be employed substantial electrolyte liquid depths creating considerable head pressures generally greater than at least about 1 psi (ca. 0.69 dynes/cm.sup.

Abstract: An electrolytic cell for separating chlorine gas from other (foreign) gases, having an anode, a cathode assembly, an aqueous electrolyte, a housing, and a constant voltage power supply. The cathode assembly is generally comprised of a dense graphite electrode having a winding channel formed in the face opposing the anode, a gas impermeable (but liquid permeable) membrane sealed into the side of the cathode electrode over the channel, and a packing of graphite particles contained in the channel of the cathode electrode. The housing separates and parallelly aligns the anode and cathode assembly, and provides a hermetic seal for the cell. In operation, a stream of chlorine and foreign gases enters the cell at the beginning of the cathode electrode channel. The chlorine gas is dissolved into the electrolyte and electrochemically reduced into chloride ions. The chloride ions disfuse through the gas impermeable membrane, and are electrochemically oxidized at the anode into purified chlorine gas.

Abstract: An electrolytic cell for separating chlorine gas from other (foreign) gases, having an anode electrode, a cathode electrode, a gas impermeable (but liquid permeable) membrane interposed between the anode and cathode electrodes, an aqueous electrolyte, a housing, and a constant voltage power supply. The electrolytic cell may be constructed in either a rectangular or cylindrical geometry, and may be combined with other electrolytic cells to form a multiple cell system. In operation, a stream of chlorine and foreign gases enters the cell at the lower portion of the cathode electrode. The chlorine gas is dissolved into the electrolytic and electrochemically reduced into chloride ions. The chloride ions diffuse through the gas impermeable membrane, and are electrochemically oxidized at the anode into purified chlorine gas. The foreign gases do not participate in the above, and are vented from the cell.

Abstract: A unique, current conducting bipolar separator in a cell for electrolysis of chlorides makes multiple contact with the anodes and cathodes bonded to an ion transporting membrane in an electrolysis cell. Each side of the separator plate includes a plurality of electrode contacting, current conducting ribs or projections which also define a plurality of flow channels to allow fluid transport and good flow distribution. The projections or ribs on opposite sides of the separator plates are angularly disposed relative to each other so that the membrane is supported on one side by ribs of one separator and on the other side by the ribs from another separator which are angularly disposed to the first group. The intersection of the ribs on opposite sides of the membrane, thus, establishes a plurality of pressure areas or bearing surfaces which support the membrane without deforming it and without requiring very precise registration and alignment of the ribs.

Abstract: A gas diffusion semiconductor electrode and solar cell and a process for gaseous fixation, such as nitrogen photoreduction, CO.sub.2 photoreduction and fuel gas photo-oxidation. The gas diffusion photosensitive electrode has a central electrolyte-porous matrix with an activated semiconductor material on one side adapted to be in contact with an electrolyte and a hydrophobic gas diffusion region on the opposite side adapted to be in contact with a supply of molecular gas.

Abstract: A chlorine generator is disclosed as including an assembly for an electrolytic cell generating the chlorine and a separate assembly for feeding the chlorine gas into a body of water. The cell assembly preferably includes two separate electrolytic solutions separated by an ion permeable membrane, such that an anode and a cathode are positioned on each side of the membrane. The gas feed assembly is in fluid communication with the cell housing by two separate conduits which accommodate the flow of gas from the cell to the feed assembly, within which the gases are accumulated and intermixed with a portion of water which has been diverted from the main body of water to flow through the feed assembly and then back to the main body of water.

Abstract: An electrolytic process and an electrolytic cell for recovering metal values from low grade concentrates. The said concentrate is introduced into the cell containing an aqueous electrolyte so that it is retained in proximity to an anode or anodes and kept out of contact from the or each cathode. The cell is energized so that electrolysis takes place and acid is released at the anode(s) which dissolves the metal values which form cations which migrate to and are discharged at the cathode(s). The impurities in the concentrate form fine particles which are separated from the concentrate by screening, e.g. by means of a grid or grids separating the anodes from the cathodes.

Abstract: Novel electrodes for oxygen ionization half-cell electrode reactions comprising an electrically conductive porous base having over at least a portion thereof a coating containing an electrocatalyst comprising (1) at least one metal selected from the group consisting of silver and a platinum group metal and (2) a hydrated oxide of at least one metal selected from the group consisting of manganese and nickel, electrochemical cells containing the said electrode at which oxygen is ionized and to novel electrolytic processes with such an electrode.

Abstract: A process and an apparatus for electrowinning metal from metal bearing solutions is disclosed. A support solution containing a predetermined metal concentration is continuously recirculated through a cell having a porous grid supporting a bed of particulate conducting particles at a sufficiently high flow rate so as to fluidize and expand the bed by 5 to 25%. A gas is continuously fed through the bed of conducting particles so as to strongly agitate the particles at low bed expansion to maintain good mixing and uniform fluidization of the bed of particles. The cell includes an electrode arrangement suspended from the top of the cell and immersed into the bed of fluidized conducting particles.

Abstract: A compound cell for performing an electrochemical reaction at high temperature consists essentially of hollow, cylindrical bodies of a ceramic electrolyte, rings of an electronically conductive material coaxially interposed between each pair of electrolyte bodies, annular layers of ceramic insulating material bonding each ring to at least one of the two adjacent electrolyte bodies, the bodies, rings, and annular layers being diffusion welded to each other to form a cylindrical, gas-tight tube. A pair of electrode layers is associated with each electrolyte body, one layer of the pair covering the associated body inside the tube and conductively engaging one of the two adjacent rings, the other electrode layer of the pair covering the associated body outside the tube and conductively engaging the other adjacent ring.

Abstract: An improved process and apparatus for pH control and energy savings in chlor-alkali electrolyis cells is disclosed wherein a fuel cell type spaced porous catalytic anode is utilized to chemically oxidize a controlled, sub stoichiometric amount of hydrogen to provide hydrogen ions to a recirculating anolyte. The pH is monitored and the flow of hydrogen fuel adjusted to provide a resultant desired pH in the range of about 2 to about 4. Optionally, hydrogen gas produced at the cell cathode may comprise the fuel supply and a spaced porous catalytic cathode may be employed for hydrogen supply control and depolarization.

Abstract: High current efficiency can be obtained in an electrolytic cell by inducing turbulence in the catholyte preferably by utilizing a gas-directing cathode and cation-permselective membrane combination. There is disclosed a process for electrolysis, particularly, the electrolysis of an alkali metal chloride such as sodium chloride to produce chlorine and sodium hydroxide. Said cell has a cathode and an anode divided into catholyte and anolyte compartments by a cation-permselective membrane. Turbulence inducing means such as a gas-directing cathode provides turbulence in said catholyte at the surface of said membrane by directing gas evolving on said cathode toward or away from said membrane. Multicell arrangements are also disclosed wherein said cells are connected in series.

Abstract: In the electrolytic production of hydrogen and oxygen, air is pumped through the cell while the electrolysis is in progress so as to obtain a mixture of air with the electrolytically produced hydrogen and oxygen.

Abstract: The invention relates to an improvement in an electrolytic cell having an anode positioned within an anode chamber and an oxidizing gas depolarized cathode positioned within a cathode chamber adapted to contain a catholyte, said cathode chamber spaced apart from the anode chamber by a cation-permeable partition. The improved cell comprises the cathode having a cellular metal structure comprising a continuous interconnected network of electrolytically deposited metal defining therebetween a plurality of substantially convex and substantially electrically nonconductive cellular compartments. The arrangement of the compartments is adapted to permit passage of the oxidizing gas to the catholyte. The cellular metal structure is further characterized in that the deposited metal interfaces the cellular compartments within the cellular metal structure.

Abstract: A process is provided for purifying salt-containing water into desired form, wherein a salt-containing water stream is mixed with hydrogen and then pumped into an electrochemical cell where hydrogen is ionized into protons. These protons migrating to the counter-electrode, under the influence of an applied potential, entrain liquid water. At the counter-electrode, protons recombine to form hydrogen while releasing liquid water. Hydrogen is recycled and participates into the process only as a vehicle for the transport of water. This process is particularly applicable to the purification of water with high salt content such as sea water.Apparatus for carrying out the above process is also provided.

Abstract: A novel electrolytic cell is described for carrying out electrochemical reactions in which a gas and a liquid electrolyte flow co-currently through a fluid permeable conductive mass which acts as an electrode. The cell has an anode and cathode in spaced apart relationship, with one electrode being in the form of a fluid permeable conductive mass e.g. a porous matrix or a packed bed of graphite particles, separated from the counter electrode by a barrier wall. This barrier wall can be either anion specific membrane dividing the cell into separate cathode and anode chambers or a porous insulating wall permitting flow of electrolyte between the cathode and anode. A liquid electrolyte and a gas are passed co-currently through the electrode bed perpendicular to the current flow and the reaction product is generated in the solution within the electrode bed.

Abstract: Disclosed is an improved wafer electrode for use in an electrolytic cell, having an access tube to direct a fluid across the electrode plate or to remove fluid from near the electrode plate within the cell. Cells employing the subject wafer electrode in an electrolytic cell can be used for various electrochemical processes such as for the production of alkali metal carbonates.

Abstract: Disclosed is a method and apparatus for the concentration and purification of a cell liquor containing sodium or potassium hydroxide wherein the three compartment electrolytic cell has a porous catalytic anode, a porous asbestos diaphragm separating the anode compartment and a central compartment having a stratification network, a cation-exchange membrane separating the central compartment and a cathode compartment having cathode disposed therein such that an electrolyzing current may be passed between the anode and cathode. Hydrogen gas emanating from the cathode and anode compartments is fed into the porous catalytic anode to decrease the potential across the cell below the evolution potential for chlorine and coincidently reduce the power requirements of the cell, which is operated at elevated temperatures.

Abstract: An assembly of electrodes suitably for use in electrochemical processes, comprising a plurality of elongated conductive elements as electrodes arranged substantially in parallel in a vertical plane and spaced apart from each other. At least one elongated non-conductive element is interposed between every two adjacent conductive elements. Preferably, both the conductive and non-conductive elements are flexible and the assembly comprises a base fabric of non-conductive material and a plurality of conductive elements incorporated in said base fabric.

Abstract: Improved apparatus and process to electrolytically produce chlorine gas and an alkali metal hydroxide in a diaphragm cell. The improved process comprises circulating the catholyte and contacting a foraminous cathode with an oxidizing gas having a regulatably controlled moisture content.

Abstract: Improved apparatus and process to electrolytically produce chlorine gas and an alkali metal hydroxide in a diaphragm cell. The improved process comprises employing a cation exchange diaphragm and contacting a foraminous cathode with an oxidizing gas having a regulatably controlled moisture content, while substantially simultaneously regulating the anolyte and catholyte compositions. The catholyte upper surface level is kept at a higher level than the anolyte upper surface.

Abstract: A method of making an electrode for preparing hydrogen peroxide, according o which active carbon during application of heat is mixed with a binder and a hydrophobic substance of addition. The thus obtained mixture is applied to an electrically conductive carrier structure. More specifically, active carbon is glowed in a vacuum at a temperature above 900.degree., preferably at a temperature of from 1000.degree. to 1250.degree.C. After the active carbon powder has been cooled in a vacuum, the active carbon powder is mixed with a solvent containing the binder and the hydrophobic substance of addition. The thus obtained mixture is applied to the electric conductive carrier substance. Finally, the mixture thus applied to the carrier structure is dried. The thus produced electrode is arranged in an electrolytic cell filled with an electrolyte.

Abstract: A cell for producing metal by electrolysis of aqueous solutions of the relevant chloride comprises at least one electrolytic tank having upright cathodes and upright insoluble anodes alternating in the longitudinal direction of the tank, each anode being surrounded by an anodic box whose sides which face cathodes each comprise a diaphragm, the cell further comprising means of collecting and recovering the chlorine released during electrolysis, means of drawing off vapor generated at the surface of the electrolyte, means of blowing gas into the bottom of the tank below each cathode, and rack-mounted U-shaped guide-rail locating means for use in placing and for retaining in position the cathodes, the anodes and the anodic boxes.