Abstract: A molten salt reactor for potentiostatic electroplating that includes a rtor chamber defined by a peripheral wall, a bottom wall and a top cover. The bottom wall of the reactor chamber has an opening, to which a first end of a gas inlet conduit is attached so as to be in fluid communication with the reactor chamber. A crucible support platform is positioned within the reactor chamber, and a crucible for holding a molten salt is mounted thereon. A furnace substantially surrounds the peripheral wall of the reactor chamber and the first end of the gas inlet conduit. The crucible support platform is electrically insulated from the reactor chamber. An inert gas flows from the gas inlet conduit, through a lower portion of the reactor chamber, past the crucible support platform, through an upper portion of the reactor chamber, and to a gas outlet in the upper portion of the reactor chamber.

Abstract: A method of, and an apparatus for, introducing at least one halide into the bath of cell for dry electrolysis. The method confines a portion of the bath in an annular space and upward motion is imparted to the confined portion of the bath by introduction of a gas and halide into the annular space. The apparatus for carrying out the method consists of two concentric tubes: an inner tube through which the halide and the gas are introduced and which tube is open at its bottom end and which tube has orifices on its lateral wall; and an outer tube which is open at its bottom end, closed at the top end and provided on its lateral wall with apertures situated at a level higher than that of the orifices. The method and apparatus can be applied to the operation and construction of electrolysis baths in which the concentration by weight of the halide and its mean valency must be maintained within a narrow range and be able to be adjusted progressively and precisely.

Abstract: An electrolysis apparatus has a furnace for setting a silica glass component such as a process tube or crucible, a heater for heating the component, a sensor for measuring a temperature of an inside portion of the furnace, an anode and an cathode for applying a voltage across the component so as to electrolyze the component, a tube for holding the anode, a device for supplying an inert gas into a space between the anode and the holding tube, and a DC power source connected to the anode and the cathode.

Abstract: An apparatus and process for reducing uranium and/or plutonium oxides to produce a solid, high-purity metal. The apparatus is an electrolyte cell consisting of a first container, and a smaller second container within the first container. An electrolyte fills both containers, the level of the electrolyte in the first container being above the top of the second container so that the electrolyte can be circulated between the containers. The anode is positioned in the first container while the cathode is located in the second container. Means are provided for passing an inert gas into the electrolyte near the lower end of the anode to sparge the electrolyte and to remove gases which form on the anode during the reduction operation. Means are also provided for mixing and stirring the electrolyte in the first container to solubilize the metal oxide in the electrolyte and to transport the electrolyte containing dissolved oxide into contact with the cathode in the second container.

Abstract: A method of electrolytically producing lithium includes providing an electrolytic cell having an anode compartment and a cathode compartment. The compartments are separated by a porous electrically nonconductive membrane which will be wetted by the electrolyte and permit migration of lithium ions therethrough. Lithium carbonate is introduced into the anode compartment and produces delivery of lithium ions from the anode compartment to the cathode compartment where such ions are converted into lithium metal. The membrane is preferably a non-glass oxide membrane such as a magnesium oxide membrane. The membrane serves to resist undesired backflow of the lithium from the cathode compartment through the membrane into the anode compartment. Undesired communication between the anode and cathode is further resisted by separating the air spaces thereover. This may be accomplished by applying an inert gas purge and a positive pressure in the cathode compartment.

Abstract: The present invention provides an apparatus for producing lithium from an aluminum-lithium alloy scrap comprising (a) a dryer for removing moisture from solid aluminum-lithium alloy; (b) a reservoir for heating and holding molten aluminum-lithium alloy; (c) a three-layered electrolysis cell comprising a most dense lowest layer of molten aluminum-lithium alloy, a middle layer of molten salt electrolyte, and an uppermost layer of molten lithium; and (d) a reactive gas fluxing unit to remove water present in the molten salt.

Abstract: A method of producing titanium. A quantity of titianium is heated in a crucible to provide a melt, and a layer of slag, containing an ionizable titanium compound, such as titanium dioxide, along with ionizable slag constituents, is disposed on the top of the melt. The slag is then heated to a molten state by direct current plasma arc heating with the melt being anodic. After the slag is molten, the polarity of the plasma arc heating is reversed so that the melt is cathodic, causing the slag to act as an electron transfer layer so that the titanium dioxide of the slag is reduced to titanium and any dissolved oxygen in the melt is converted to an ionic species of oxygen at the interface between the slag and the melt. The resulting liquid titanium is combined with the melt, while the ionic species of oxygen is carried upwardly through the slag and released from the slag layer by an oxidation process.

Abstract: An electrochemical separation of oxygen from oxygen containing gaseous mixtures, such as air, using an oxygen containing molten inorganic salt electrolyte retained in a porous matrix between two gas porous catalytic electrodes wherein oxygen is separated from the gaseous mixture when electrical potential is applied across the electrodes providing movement of non-metallic oxygen containing ion from the cathode to the anode.

Abstract: A method for making light metal-alkali metal master alloy using alkali metal containing scrap comprises: (a) establishing an electrolytic cell divided into two or more laterally adjacent areas by porous alkali metal ion transport means, said cell including a first cell area supplied with alkali metal-containing scrap and a second cell area consisting essentially of molten light metal; (b) supplying current to this cell for transporting alkali metal ions from the first cell area to the second cell area; (c) forming master alloy by combining these ions with the molten light metal in said second cell area; and (d) withdrawing master alloy from the second cell area. An apparatus for making aluminum-lithium or magnesium-lithium master alloy using the lithium from aluminum-lithium alloy scrap is also disclosed.

Abstract: A method of producing titanium. A quantity of titanium is heated in a crucible to provide a melt, and a layer of slag, containing an ionizable titanium compound, such as titanium dioxide, along with ionizable slag constituents, is disposed on the top of the melt. The slag is then heated to a molten state by direct current plasma arc heating with the melt being anodic. After the slag is molten, the polarity of the plasma arc heating is reversed so that the melt is cathodic, causing the slag to act as an electron transfer layer so that the titanium dioxide of the slag is reduced to titanium and any dissolved oxygen in the melt is converted to an ionic species of oxygen at the interface between the slag and the melt. The resulting liquid titanium is combined with the melt, while the ionic species of oxygen is carried upwardly through the slag and released from the slag layer by an oxidation process.

Abstract: The invention relates to a process for regulating the acidity of the electrolytic bath by recycling fluorinated effluents emitted by the Hall-Heroult electrolytic cells for the production of aluminum, in which said fluorinated effluents are collected, by the dry route, on the alumina. It comprises the following stages:a reference value for the fluorine/alumina weight ratio is fixed in connection with the alumina leaving the collecting apparatus,a continuous measurement takes place of the fluorine and alumina quantities entering the collecting apparatus,the alumina flow rate is regulated so as to maintain the F/Al.sub.2 O.sub.3 ratio at its reference value, generally fixed between 0.

Abstract: In this field it is a problem to find practical technical solutions for heat recovery at the same time as regulation and control of the temperature conditions during cell operation is difficult, especially when cooling of the cell is intended. The arrangement comprises cooling chambers (6A, 6B, 6C, 6', 51) each having a base area covering a small proportion of the surface of each cell. Together these cooling chambers cover a substantial proportion of the cell surface without any significant space between the cooling chambers. These are adapted to receive a through-flow of a cooling medium which is controlled (8A, 8B, 8C) individually for each cooling chamber, and the cooling medium preferably is helium.

Abstract: A process and an apparatus for producing a neodymium-iron alloy by electrolytic reduction of neodymium fluoride in a bath of molten electrolyte, consisting essentially of 35-76% by weight of neodymium fluoride, 20-60% by weight of lithium fluoride, up to 40% by weight of barium fluoride and up to 20% by weight of calcium fluoride, conducted between one or more iron cathode and one or more carbon anode.

Abstract: This invention relates to a process of producing lithium metal by the electrolysis of fused mixed salts comprising electrolyzing fused mixed salts consisting of lithium chloride and potassium chloride in a diaphragmless electrolytic cell, withdrawing molten lithium metal from the cell to a receiver and cooling the lithium metal which has been withdrawn.

Abstract: This invention relates to a cell for producing a metal by electrolyzing halides in a molten salt bath. It consists of using one cathode in the form of a basket, simultaneously passing a current I.sub.1 between this cathode and an anode in such a manner as to carry out a first deposit of crude metal in the basket and a current I.sub.2 between the said basket and complimentary cathodes for depositing the final metal thereon. The cell consists of a central anodic system, a tubular cathodic basket surrounding the anode and a series of cathodes surrounding this basket, a positioning which cathodes can be reversed in relation to the basket.

Abstract: The plant for the electrolytic production of a metal in a molten salt bath by deposition at the cathode in the solid state includes an outer casing, means for maintaining an atmosphere inert to the metal to be produced in the casing, a container within the casing and arranged to contain the molten salt bath and having a movable cover, a plurality of electrodes suspended in the molten salt bath each bearing on means for supporting it and connecting it electrically, the means comprising for each of the electrodes a pair of electrically conductive elements facing each other and supported respectively by two opposite walls of the container and handling means associated with the outer casing for removing any one of the electrodes from the container after raising of the movable cover.

Abstract: The invention comprises an improved Hall cell for electrolytic reduction of aluminum from a molten salt bath having a carbon cathode bottom wall and sidewall, a cover over said cell, at least one anode within said cell depending from an anode support rod passing through said cover, conductive means over the carbon bottom wall to reduce the spacing between the anode and the cathode, and protective sidewall lining means relatively inert to attack by the molten salt bath on the inner surface of the carbon sidewall. Cooling means are provided to cool an upper portion of the sidewall lining adjacent the surface of the molten salt bath to promote the formation of a protective layer of frozen bath over the exposed portion of the sidewall lining adjacent the surface of the molten salt bath while retaining within the cell at least a portion of the heat removed from the sidewall lining.

Abstract: The invention is an improvement in the construction of a Hall cell for the production of aluminum by electrolytic reduction of alumina in a molten salt bath wherein a conductive carbon cathode lining comprising a bottom wall and a sidewall is surrounded adjacent the outer surface thereof with an insulating layer, and a layer of conductive material overlies the inner surface of at least the bottom wall of the carbon lining to reduce the effective spacing between the cathode and one or more anodes in the cell to thereby reduce the power consumption of the cell. The improvement comprises an air passageway between the insulating layer and the outer surface of the carbon lining sidewall and an air inlet port adjacent the bottom of the passageway for passing air into the air passageway and along the outer surface of the carbon lining sidewall whereby the carbon sidewall may be cooled sufficiently to permit the formation of a protective layer of frozen bath on the inner surface thereof.

Abstract: Separating volatile impurities from AlCl.sub.3 by supplying impure AlCl.sub.3 into a molten salt bath of a gas separation compartment in an electrolysis cell. The impurities are removed from the compartment and molten salt bath containing dissolved AlCl.sub.3 is carried under a partition into a chamber where the AlCl.sub.3 is electrolyzed. In a preferred embodiment, desublimation is avoided by supplying AlCl.sub.3 to the bath as a gas rather than in solid form.

Abstract: An electrolytic cell is described for continuously producing multivalent metals, in particular titanium and titanium alloys. The cell is physically separated into a plurality of zones to better control the stepwise reduction of the multivalent metal. To further increase control over the stepwise reduction process, each zone is also provided with a reference electrode for controlling the voltage potential at each cathode. A process for reducing and plating the multivalent metal is also described.

Abstract: An apparatus for electrolysis of MgCl.sub.

Abstract: Device and process for automatic, process-controlled feeding of electrolytic cells for producing aluminum. Besides a low degree of wear on the feed pipes, a fast and accurate feeding of fluxing agents to a particular cell is assured.

Abstract: Conventional fused salt reduction cells feature anode conductor sections which are spaced apart and have the function of feeding electric current to the anodes via anode rods. An electrically insulated footbridge positioned over the cell between the anode conductor sections makes it possible to walk above the cell. A housing with slight positive pressure created by the supply of fresh air to it, is preferably provided over this footbridge. Transverse cells are arranged asymmetrically in a pot room. An air-tight, closeable walk-way i.e. gangway is provided on the inside or outside of the long wall of the pot room. Extensions to the cell housings lead to appropriate openings in the long wall of the pot room or to the longitudinal wall of a gangway in the interior of the pot room. The fresh air is passed through the gangway and emerges from the open end of the cell housing.

Abstract: The invention concerns a process and a device for controlled feed of alumina and halogen additives into a vat for production of aluminum by alumina electrolysis according to the Hall-Heroult technique.The alumina or the halogen additive, set aside by gravity into the storage means, is introduced into a volumetric feed regulator and dispatched under the effect of a jet of compressed air, as far as the orifice of introduction into the electrolysis vat, through a rigid system of pipes, in successive equal or unequal dosed quantities, at constant or variable time intervals. The device includes no moving piece which is subject to wear or abrasion.

Abstract: In the production of magnesium by electrolysis of a fused salt the metal is collected over a body of the fused salt under a heavily insulated cover to reduce heat loss from the molten metal under a substantially non-oxidizing atmosphere. The electrolyte is held down to a controlled temperature somewhat above the melting point of magnesium by means of a heat exchanger which projects into the fused electrolyte and is arranged so as to avoid significant uptake of heat from the supernatant molten metal. This arrangement permits the electrolyte temperature to be controlled with reduced formation of sludge and extended cell life by avoidance of exposure of the electrolyte to atmospheric moisture.

Abstract: The anode effect which is necessary in the electrolytic cell can be extinguished after a short time if, immediately after it appears, fine granular salts are introduced together with an injection medium through a suitable channel into the electrolyte and under the anodes. These salts which are not harmful to the electrolytic process cause vigorous production of gases at the operating temperature of the cell. The channel for introducing the salts and the injection medium is usefully situated in the crust breaking chisel or a lance which can be lowered into the bath. The device comprises further a storage vessel for salts which has a closing facility which is activated via a closing piston, below that a combined measuring and injection chamber featuring an injection nozzle and a tube with by-pass connecting up to the injection chisel or lance.

Abstract: An improved galvanizing device for the galvanic precipitation of aluminum from an anhydrous, aprotic, and oxygen-free aluminum-organic electrolyte is provided. The known device having an annularly shaped galvanizing trough, which is sealed from the atmosphere and which utilizes a centrally located, rotatable support mechanism which guides the goods carriers through the electrolyte in a circular, rotating manner, and also furnishes the goods carriers with an electrical contact, is herein provided with separate charging and discharging locks attached to the galvanizing trough. Each of the locks is provided with a U-shaped fluid lock to maintain the gaseous seal and an endless chain conveyor to transport the goods carriers to and from the galvanizing trough. Additionally, the anode plates which are located in the electrolyte trough are provided with a transport rod to permit their removal and replacement in a manner similar to that utilized with the goods carriers.

Abstract: The apparatus and the process according to the invention concern the preparation of titanium by electrolysis in a bath of molten halides.The apparatus comprises a porous diaphragm which is disposed around a feed cathode permitting partial reduction of the TiCl.sub.4 introduced into the electrolyte.The intensity of the current which passes through the feed cathode is so regulated as to maintain a low but non-zero voltage drop, across the diaphragm which is insulated with respect to the feed cathode.

Abstract: In the production of aluminum by electrolytically reducing alumina dissolved in a fused fluoride salt mainly composed of cryolite, the present invention aims to reduce the cell voltage and/or to increase the inter-electrode distance of an aluminum electrolytic cell with a self baking type electrode, thereby reducing the specific electric power consumption. The present invention also automatically eliminates the anode effect. This is achieved by introducing a gas to the lower surface of the carbon anode in contact with the electrolytic bath, via at least one aperture passing in an essentially vertical direction through the carbon anode.

Abstract: The process according to the invention concerns the production of polyvalent metals such as titanium by electrolysis of molten halides.It comprises controlling the permeability of the diaphragm which separates the anolyte from the catholyte, by causing growth or re-dissolution of a deposit of the metal to be produced.The process is applied in particular to the production of titanium by electrolysis from TiCl.sub.4.

Abstract: Apparatus for transferring powdered ore from a storage tank to a bin associated with an electrolytic cell. The cell defines a chamber containing an electrolyte and includes means for transferring ore from the bin to the chamber. The apparatus comprises a fluidizing conveyor for conveying powdered ore from a storage tank to the bin, a first vent interconnecting the conveyor and bin and a second vent interconnecting the bin and chamber. In a preferred embodiment, a source of pressurized gas causes ore to flow through the conveyor, and the apparatus further comprises a pressure switch for closing the source in response to a buildup of fluid pressure in the conveyor. Another preferred feature is a fluidizing pad inside a conduit connecting the storage tank to the conveyor.

Abstract: A Castner type electrolysis cell, operating to produce alkali metal from molten alkali hydroxide, forms water at its anode which dissolves in surrounding anolyte. Normally, the water is itself electrolyzed and consumes as much electrical current at the Castner cell operating voltage as does production of the alkali metal. Since water has substantially lower decompositon voltage than alkali metal, electrolysis of water in the Castner cell represents unrecoverable energy loss.This invention improves energy efficiency of alkali hydroxide electrolysis by electrolyzing the formed water at a lower voltage to produce hydrogen and oxygen and by reacting the hydrogen and oxygen electrochemically to recover a portion of the electrical energy used for the electrolysis of water. An anolyte electrolytic dehydrator, which is a cell designed for electrolysis of water in molten alkali hydroxide, receives anolyte from the Castner cell and dehydrates the anolyte by electrolysis for return to the Castner cell.

Abstract: To prevent transport of deleterious oxygen and moisture to liquid electrolyte in an aluminum electroplating vessel, workpieces move towards the vessel through an antechamber containing inert gas under pressure and comprising a plenum chamber opening downwardly into a lock chamber containing aprotic liquid. They move down into the liquid, then up out of it, into and through an inverted-U-shaped passageway containing higher pressure inert gas and which communicates with the lock chamber below the surface of the liquid therein and communicates with the electrolysis vessel above the surface of the electrolyte. At each connection between parts, where atmospheric oxygen might move towards the electrolyte, there are double mechanical seals defining a substantially annular chamber filled with aprotic liquid that forms a gas barrier, and such liquid is, where possible, shielded by inert gas.

Abstract: The operating characteristics of a Downs-type electrolytic cell are improved by incorporating a sealed weir between the riser/cooler and the molten metal receiver and by providing means for venting inert gas from the receiver through the vapor space of the riser/cooler.

Abstract: An apparatus is arranged over the bath of an electrolytic furnace containing molten aluminium.The apparatus has beams with tools which can be raised and lowered in a reciprocal manner to break-up the crust which forms on the top of the molten aluminium. Reservoirs containing alumina are also carried by the beams and serve to selectively charge quantities of alumina into the bath. Probes or lances are extendible and retractible in relation to the beams and serve to inject air into the molten aluminium.

Abstract: A process and apparatus for the collection of the gases from a tank for the production of aluminum by igneous electrolysis. In the process, the crust that covers the electrolytic solution is pierced, the hole thus obtained is kept open and the gases flowing from it are collected. The invention applies to alumina igneous electrolysis tanks and, more specifically, to tanks making use of preheated multiple anodes.

Abstract: A process for the electrolysis of a molten charge in particular of aluminum oxide, in a cell which is fitted with one or more anodes whose working surfaces are of ceramic oxide material. The parts of the anode surface which are not protected from corrosive attack by means of a sufficiently high current density are subjected to a stream of oxidizing gas.

Abstract: A readily oxidizable metal such as lithium formed along a cathode is collected in an electrolytic tank within a collecting chamber, the level of electrolyte is caused to rise to a predetermined top level at which the lithium leaves the collecting chamber and overflows into a transfer compartment, the level of electrolyte is lowered to a predetermined bottom level at which the poured-off lithium leaves the transfer compartment and passes to the discharge compartment, the level of electrolyte is raised to the top level in order to ensure overflow into a discharge tube. A stream of inert gas is passed into the discharge compartment and the lithium is transferred to a chamber for treatment in an inert atmosphere and conversion to ingots in the pure state.

Abstract: Process for operating a cell for the electrolysis of a molten charge, in particular aluminum oxide, with one or more anodes, the working surfaces of which are of ceramic oxide material, and anode for carrying out the process.In the process a current density above a minimum value is maintained over the whole anode surface which comes into contact with the molten electrolyte. An anode for carrying out the process is provided at least in the region of the interface between electrolyte and surrounding atmosphere, the three phase zone, with a protective ring of electrically insulating material which is resistant to attack by the electrolyte. The anode may be fitted with a current distributor for attaining a better current distribution.