Abstract: In the production of fluorine by electrolysis of a fused electrolyte containing potassium fluoride and hydrogen fluoride the electrolyte is circulated from a tank, through a heat exchanger, through one or more electrolytic cells and is returned to the tank. The heat exchanger controls the temperature of the circulating electrolyte leaving the electrolytic cell or cells at the desired value in the range 75.degree.-110.degree. C.

Abstract: A method of electrochemically polishing a metal body which comprises juxtaposing the surface to be polished with a tool electrode in the presence of an abrasive and an electrolyte, and applying pulses having a duration not exceeding 100 microseconds between the electrode and the workpiece with the electrode being poled negatively.

Abstract: In the electrolytic production in water of insoluble metal hydroxide from the metal thereof, more especially of coagulant ferric hydroxide from iron, rectangular channels with flanking ribs provide for pre-established, uniform spacing of the electrode plates and intermediate binary wiping structures. Electrolytic current contact is protected against corrosion by a metallic embossment on the plates. Binary reciprocating wipers are at different wiping levels between successive plates and reversely directed to the opposite surfaces thereof. The wipers are urged against the plate surface by bilateral springs, as the surfaces recede due to thinning of the plates as they are consumed. Terminal panels, on which the wipers land after a reciprocating stroke, coextensively bound the plates; protuberances facilitate the transit of a wiper between them. The terminal panels may be employed to concurrently generate oxygen or chlorine as a supplement to coagulant ferric hydroxide.

Abstract: The amount of bulging and cracking in the carbon floor of an electrolytic reduction cell for the production of aluminium is reduced by the provision of a recess in the steel container which accommodates the carbon floor as it expands. The recess is filled with a first material which is easily compressible and a second material which deforms only at a relatively higher load and transmits the expansion forces to the steel container without producing any permanent deformation thereof.

Abstract: A bipolar unit for an electrolytic cell comprising(a) an anode comprising a group of elongated members, e.g. wires or rods, of a film-forming metal carrying on at least part of their surfaces an electrocatalytically active coating, the members being electrically conductively mounted on and projecting from a sheet of a film-forming metal so that a part of the members lies in a plane laterally spaced from the sheet, and parallel thereto, and(b) a cathode comprising a group of elongated metal members electrically conductively mounted on and projecting from a metal sheet so that a part of the members lies in a plane laterally spaced from the sheet,The elongated members in at least one of the groups being flexible and the sheets of film-forming anode metal and of cathode metal being electrically conductively bonded to each other.

Abstract: A process is provided for producing aluminum in an electrolytic cell containing aluminum chloride dissolved in a molten solvent of higher decomposition potential. The cell has a terminal anode, a terminal cathode and a bipolar electrode arranged to operate with the anode and the cathode, providing interelectrode spaces therebetween. On electrolyzing the cell chlorine is produced on each anode surface thereof and aluminum on each cathode surface, the aluminum being swept from the cathode surface by bath material. In the process, carbonaceous material is provided for use as the electrode. The direction of grain flow constituting the carbonaceous material is determined and the electrode is arranged in the cell such that the direction of electrolysis current flow through the cell is in a direction substantially perpendicular to the direction of grain flow in the electrode.

Abstract: A technique for affixing anode support rods to the wall of a chlor-alkali type of electrolytic cell, wherein the support rod is positioned and affixed to the cell wall through a welding operation providing a leak proof seal and electrical contact, as well as providing for its easy removal and replacement for maintenance purposes.

Abstract: An electrode assembly for an electrolysis cell is provided comprising at least two opposed electrode working faces, and placing between the working faces a resilient, compressible member against which compression of the electrode takes place during its insertion into the cell. Upon inserting said electrode assembly into a smaller opening within the cell, which opening is defined by the adjacent electrodes, compression of the resilient, compressible elastic member through insertion of the electrode assembly into the opening takes place and automatically guides the assembly such that its working faces are correctly positioned relative to the adjacent electrodes. The degree of compression of each electrode assembly is determined by spacer assembly guides or appendages mounted on the electrode face. These guides determine the gap between the electrode face and adjacent electrodes.

Abstract: In the present plating method the bath contains an electrolyte solution having a uniform ion concentration. A common electrode, a plating electrode and a standard electrode are arranged in the bath. A direct current source is connected between the common electrode and the plating electrode. A further, constant, direct current source is connected between the common electrode and the standard electrode. A potentiometer device is arranged for detecting resistance changes between these electrodes due to variations in the ion concentration and in the mobility of the electrolyte solution between the electrodes. A control is responsive to the potentiometer device for regulating the plating current supplied by the direct current source as a function of the potential difference detected by the potentiometer device, whereby a constant plating current density is achieved.

Abstract: The casing of apparatus for purifying water encloses a chamber and is formed with two orifices spaced from the chamber in opposite directions and communicating with the same for gravity flow of the water to be purified from one of the orifices through the chamber and out of the other orifice. Two electrodes spacedly mounted in the chamber for flow of the water therebetween are conductively connected to an electric battery in the casing by circuitry which causes current to flow between the electrodes through the water when the water and the battery satisfy proper conditions for the functioning of the apparatus, such conditions being indicated by a sensible signal. A compartment in the casing, sealed from the electrode chamber, encloses almost all the circuitry.

Abstract: The specification describes an electrolytic cell for the treatment of water, comprising a closed container with a lower inlet opening and an upper outlet opening for the water and a cathode and an anode. In the interior of the electrolytic cell particles are located whose density is higher than that of water and which are prevented from leaving the electrolytic cell by gratings adjacent to the inlet and the outlet.

Abstract: An improved bipolar electrode having an anodic member and a cathodic member connected in an assembled position spaced a distance apart with a connector constructed of an electrically conductive material disposed between and engaging portions of the anodic member and the cathodic member, the connector mechanically supporting the anodic and the cathodic members in a spaced apart relationship and establishing electrical continuity therebetween.

Abstract: A purification unit includes an electrolytic cell adapted to hold a body of water to be purified and provided with two electrically insulated electrodes, a pump supplying the water to be purified to the cell through a filter and driving purified water out of the unit, a power supply for supplying electrolyzing current to the electrodes, a control circuit which generates a sensible signal indicative of the operating conditions of the pump, the power supply, and the filter, and a housing which encloses the cell, the pump, the power supply, and the control circuit. The housing is partly received in a container for the raw water. The portion of the housing projecting from the container carries a discharge spout for purified water, a connector for an external source of current, and the signal display elements of the control circuit.

Abstract: A method of preventing the conduction of electricity along a film of molten salt on a surface. An electrically insulating material which is not wet by the molten salt is interposed in the film. The material is in the form of a protrusion on the surface.

Abstract: In an electrolytic alumina reduction cell having a cathode formed by carbon blocks at the bottom and a side wall made of carbon substrate, a heat insulating substrate is interposed at the boundary between the cathode at the bottom and the side wall so as to prevent heat transfer from the bottom to the side wall. The stable solid bath is formed on the inner side wall of the electrolytic cell whereby the heat radiation from the electrolytic cell can be reduced and the heat energy can be saved.

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: A machine for simultaneously electrochemical processing a plurality of workpieces in which a workpiece receiver is mounted on spring loaded rails between a clamping unit and a base for horizontal movement between loading and operating positions. A working electrode extends through a bore in the clamping unit to create a working gap with a workpiece which is electrically connected via a spring loaded contact member to a source of eroding current. The clamping unit can be moved up and down to make and break electrical contact and to clamp and release the workpieces. Electrolyte is supplied to and removed from the working gap.

Abstract: An assembly for an electrolytic cell comprising a base plate of an electrically conductive metal which is unattacked by the electrolyte to be used in the cell, e.g. titanium, a plurality of anodes or anode support members mounted on and attached in electrical contact with one surface of the base plate, and an electrical conductor in the form of a metallic sheet electrically conductively bonded to the other surface of the base plate, e.g. a sheet of iron or steel, the bonding having been achieved by placing a metallic inter layer between the base plate and the conductor sheet, heating the inter layer to a temperature of at least 427.degree. and to a temperature at which the inter layer is molten, and applying elevated pressure to the base plate and to the conductor sheet.

Abstract: An improved electrode having a porous nickel surface layer of greater than 75 microns in thickness and at least 11% in porosity is produced by a process which includes interdiffusing aluminum and nickel at a temperature of at least 660.degree. C. to form a nickel-aluminum alloy layer from which aluminum is subsequently selectively dissolved. When used as a cathode in an electrolytic cell for producing hydrogen, chlorine and caustic from brine, the improved electrode exhibits exceptionally low hydrogen overvoltage.