Abstract: Device for equipment of a cell (1) comprising an electrolytic bath (4) covered with a crust (5), with a chisel (13) that can be moved vertically between a high position in which it is above the crust (5) and a low position in which the crust (5) is perforated and in which contact is made with the bath (4), the device (11) comprising means of detecting electrical contact between the chisel (13) and the bath (4), these means comprising an electrical circuit (19) capable of making an electrical measurement between the chisel (13) and a point (20) in the cell used as an electrical reference, and taking immediate action on the actuator to cause vertical upwards displacement of the chisel when a predetermined value of an electrical measurement is reached.

Abstract: An apparatus for producing Ti by Ca reduction by the invention includes a reaction tank retaining a molten salt in which a molten salt CaCl2 is contained and Ca is dissolved, an electrolytic cell retaining a molten salt containing CaCl2, and a continuum body which is movably constructed while part of the continuum body is immersed in the molten salt either within the reaction tank or electrolytic cell. In the inventive method for producing Ti by Ca reduction, the molten salt in the electrolytic cell is electrolyzed to generate Ca on the cathode side which is transported to the reaction tank while deposited on and adheres to the continuum body, and TiCl4 is supplied to the reaction tank to generate Ti.

Abstract: A method for operating one or more electrolysis cells (43, 154, 243) for production of aluminium, the cell comprising inert or substantially inert anodes, where an oxygen containing gas (21, 126, 221) evolved by the electrolysis process in the cell is gathered and removed therefrom. The oxygen containing gas is introduced into a combustion chamber (38, 149, 238) where it is reacted with a carbon containing gas (7, 116, 209) in a combustion process. Emisions of CO2 and NOx can be reduced.

Abstract: A device and method for increasing the mass transport rate of a chemical or electrochemical process at the solid and fluid interface in a fluid cell. The device includes a membrane in close contact with surface of the work piece, to separate the process cell into two chambers, so that fluid velocity at the work piece is controlled separately from the main cell flow. Thus the diffusion boundary layer is controlled and minimized by the rate that fluid is withdrawn from the work piece chamber.

Abstract: An integrated tool is provided including at least one workpiece processing station having a paddle assembly. In accordance with another independent aspect of the present invention, the workpiece processing station is adapted for adjusting the level of the processing fluid relative to a workpiece, wherein the portion of the workpiece to be processed and possibly the paddle is selectively immersed within the processing fluid. In accordance with a further independent aspect of the present invention, a paddle is provided for use proximate to a workpiece in a workpiece processing station. The paddle includes a one or more sets of delivery ports and one or more sets of fluid recovery ports. In at least one embodiment, the paddle provides for agitation of a processing fluid proximate to the surface of the workpiece. In at least another embodiment, the paddle provides for the delivery and/or recovery of one or more fluids to the portion of the workpiece to be processed.

Abstract: An electrolysis cell (10) contains a number of carbon anodes (12) having top, bottom and side surfaces, operating in molten electrolyte (17) in an aluminum electrolysis cell (10), where gas bubbles (28) are generated at the anode surfaces and where alumina particles (20) are added to the top of the molten electrolyte, where the carbon anodes (12) have at least two inward slots (21) passing through the carbon anode (12) along the longitudinal axis 40 of the carbon anode and also passing through only one front surface (25) of the carbon anode, where the height (32) of the slots (21) is from about 45% to 80% of the anodes thickness and the slotted front surfaces (25) are disposed toward the center of the electrolysis cell so that generated gas bubbles (28) are directed to the alumina particles.

Abstract: Disclosed are a method of reducing spent oxides nuclear fuel to nuclear-fuel metal, in which metal oxides are reduced to metals using an electrochemical reduction device with LiCl—Li2O salt as an electrolyte, a cathode electrode assembly used in the method, and a reduction device including the cathode electrode assembly. The method is advantageous in that the process of reducing the spent oxide nuclear fuel to the nuclear-fuel metal and another process of recovering Li are united to simplify the whole processes, direct use of high oxidative Li metals is excluded to secure safety, and conversion efficiency of the spent oxide nuclear fuel is 99% or more.

Abstract: A method of producing aluminum in an electrolytic cell containing alumina dissolved in an electrolyte, the method comprising the steps of providing a molten salt electrolyte at a temperature of less than 900° C. having alumina dissolved therein in an electrolytic cell having a liner for containing the electrolyte, the liner having a bottom and walls extending upwardly from said bottom. A plurality of non-consumable Cu—Ni—Fe anodes and cathodes are disposed in a vertical direction in the electrolyte, the cathodes having a plate configuration and the anodes having a flat configuration to compliment the cathodes. The anodes contain apertures therethrough to permit flow of electrolyte through the apertures to provide alumina-enriched electrolyte between the anodes and the cathodes. Electrical current is passed through the anodes and through the electrolyte to the cathodes, depositing aluminum at the cathodes and producing gas at the anodes.

Abstract: A bipolar multi-purpose electrolytic cell for high current loads has a frame, two electrode edge plates with metal electrode sheet, and power supply and of bipolar plates. Each includes a plastic electrode base body with electrode rear spaces and/or with coolings spaces that are incorporated on one or both sides: incorporated supply and discharge lines for the electrolyte solutions and the cooling medium, metal electrode sheets which are applied to both sides of the base body and are solid and/or perforated in the electrochemically active area: electrolyte sealing frames, which rest on the solid metal electrode sheets and which are made of flexible plastic, and: ion exchanger membranes, which rest on the perforated metal electrode sheets and/or on the electrolyte sheets and/or on the electrolyte sealing frames and which are provided for separating the electrode spaces.

Abstract: An anode assembly for conducting electrical energy to an electrolytic smelting cell including an anode of high electrically conductive material connected to a yoke, the ends of the yoke being receivable within anodes, the yoke including a core of highly electrically conductive material and an outer structural sheath extending substantially the length of the yoke, the anode rod being in electrical contact with the core of the yoke and provided with a protective structural collar secured to the outer structural sheath of the yoke. In order for the electrical and thermal contact between the core and sheath to be maintained, the differential coefficient of thermal expansion over the operating temperature range of the assembly is preferably substantially the same or within 4×10?6 m/mk.

Abstract: Electrolysis of alumina dissolved in a molten salt electrolyte employing inert anode and cathodes, the anode having a box shape with slots for the cathodes.

Abstract: A solid material (12′) circumscribing an anode system (10) in an electrolysis apparatus is made from a mixture of cryolite and/or alumina (Al2O3), where the solid material (12′) contacts and surrounds the anodes (14, 14′).

Abstract: An electrolytic cell for producing aluminum from alumina having a reservoir for collecting molten aluminum remote from the electrolysis.

Abstract: A drained-cathode cell for the electrowinning of aluminium comprises one or more anodes (14) suspended over one or more cathodes (16). The or each anode (14) and cathode (16) respectively have a sloped V-shaped active anode surface (22) and parallel sloped inverted V-shaped drained cathode surfaces (18) facing one another and spaced apart by two sloped inter-electrode gaps (20), arranged so the electrolyte circulates upwardly in the sloped inter-electrode gaps (20) assisted by anodically produced gas and then returns from a top part (22′) to a bottom part (22″) of each inter-electrode gap (20) along an electrolyte path (26,27,36,37).

Abstract: A cell for the electrowinning of aluminum using anodes (10) made from a alloy of iron with nickel and/or cobalt is arranged to produce aluminum of low contamination and of commercial high grade quality. The cell comprises a cathode (20) of drained configuration and operates at reduced temperature without formation of a crust or ledge of solidified electrolyte. The cell is thermally insulated using an insulating cover (65,65a,65b,65c) and an insulating sidewall lining (71). The molten electrolyte (30) is substantially saturated with alumina, particularly on the electrochemically active anode surface, and with species of at least one major metal present at the surface of the nickel-iron alloy based anodes (10). The cell is preferably operated at reduced temperature from 730° to 910° C. to limit the solubility of these metal species and consequently the contamination of the product aluminum.

Abstract: An apparatus and method for removing thimbles (12) from stubs (20) of an anode yoke which includes the step of advancing a ram (20) towards each stub with the force applied by the ram against the stub being limited to a preset maximum, and another step of advancing the rams at the same speed to push the stubs through the thimbles.

Abstract: A material, for instance used as an aluminium-wettable component (21,21′, 41,41′, 51), in particular of a cell for the electrowinning of aluminium (60), comprises an openly porous or reticulated ceramic structure whose surface during use is exposed to and wetted by molten aluminium. The structure is made of ceramic material inert and resistant to molten aluminium, such as alumina, and an aluminium-wettable material that comprises metal oxide and/or partly oxidised metal, in particular of manganese, iron, cobalt, nickel, copper or zinc, which is/are reactable with molten aluminium to form a surface layer containing alumina, aluminium and metal derived from the metal oxide and/or partly oxidised metal. The ceramic structure comprises a coating of the aluminium-wettable material on the inert and resistant ceramic material, or is made of a mixture of the inert and resistant material and of the aluminium-wettable ceramic material.

Abstract: Insulation assemblies provide reduced heat loss from electrolytic metal production cells such as inert anode aluminum production cells. The insulation assemblies may be located at the end, side and/or center aisles of the cell, and may be supported by the anodes and deckplate of the cell. The assemblies reduce heat loss and bath vaporization losses, and permit stable operation of the inert anode cell.

Abstract: An apparatus and method for plating a metal onto a substrate. The apparatus generally includes an anode electrode disposed in the electrochemical cell and a cathode electrode disposed opposite the anode electrode in the electrochemical cell. The apparatus further includes an electrode lid having more than one aperture disposed between the anode electrode and the cathode electrode, the apertures configured to electrically connect the cathode electrode and the anode electrode.

Abstract: A drained cathode cell for the electrowinning of aluminium comprises a cell bottom (20) arranged to collect product aluminium and thermic insulating sidewalls (55,55′) lined with a molten electrolyte resistant sidewall lining (50) which is made of material liable to react with molten aluminium, in particular containing silicon carbide, silicon nitride or boron nitride. The thermic insulating sidewalls (55,55′) inhibit formation of an electrolyte crust on the lining (50), whereby the lining (50) is exposed to molten electrolyte. The cell bottom (20) has a peripheral surface from which the insulating sidewalls (55,55′) extend generally vertically to form, with the cell bottom, a trough for containing molten electrolyte and aluminium produced on at least one drained cathode (32).

Abstract: A cell for the electrowinning of aluminium comprises a plurality of metal-based anodes facing and spaced part from an aluminium-wettable drained cathode surface on which aluminium is produced. The drained cathode surface is formed along the cell by upper surfaces of juxtaposed carbon cathode blocks, the cathode blocks extending across the cell. The drained cathode surface is divided into quadrants by a longitudinal aluminium collection groove along the cell and by a central aluminium collection reservoir across the cell. Pairs of quadrants across the cell are inclined in a V-shape relationship, the collection groove being located along the bottom of the V-shape and arranged to collect molten aluminium draining from the drained cathode surface and evacuate it into the aluminium collection reservoir during cell operation.

Abstract: A pneumatic control system is provided for selectively controlling movement of a pneumatically-operated device between first and second working positions. The pneumatically-operated device includes a working portion and a pneumatic-control portion. The pneumatic-control portion is in fluid communication with a pressurized fluid source and includes a series of valves for selectively manipulating the working portion between the first and second working positions. The pneumatic-control portion further includes a sensing system for holding the working portion in a static mode by selectively applying system pressure to the working portion. In this manner, a more energy efficient system is provided by eliminating the need for continuous application of full line pressure.

Abstract: An object of the invention is to provide a sodium refining apparatus which has a simple constitution and does not deteriorate a solid electrolyte employed therein. The sodium refining apparatus of the invention, in which impurities contained in sodium are removed by a solid electrolyte having sodium ion conductivity, includes a bottom-closed casing made of a solid electrolyte and containing a small amount of highly pure sodium; an outer casing accommodating said bottom-closed casing and containing, outside said bottom-closed casing, impurity-containing sodium; a first electrode inserted in the impurity-containing sodium; a second electrode inserted in the highly pure sodium; and a power source for applying DC voltage to the electrodes; wherein the impurity-containing sodium and the highly pure sodium are in electrical contact with each other via the solid electrolyte.

Abstract: A method and apparatus for adding a metal, for example sodium, to a melt of a material, for example aluminum, in a vessel, in which a molten compound of the metal or a solution of a compound of the metal is provided in a container (12), the container being positioned outside the vessel, the compound is electrolytically decomposed and ions of the metal are caused to pass through a wall of a solid-state electrolyte (14) which is a conductor therefor, from a first side of the wall to an opposite second side thereof, and to combine with electrons at the second side of the wall and then to flow as molten metal from the container into the melt in the vessel.

Abstract: An electrolysis cell (10) for producing a molten metal having a density less than a density of a molten electrolyte used for producing the metal in the cell. The cell includes a section (14) for the electrolysis of a salt of the the metal contained in a molten electrolyte to form droplets of the metal in molten form contained in the electroylte; electrodes (18) within the electrolysis section for effecting the electrolysis; a metal recovery section (15) for separation of the metal from the electrolyte to form a molten metal layer, having an upper suface, floating on an upper surface of the molten electrolyte; a tapping device for periodically removing molten metal from the cell; and a reservoir (25) for withdrawal and temporary holding of molten metal separated from the electrolyte in the metal recovery section. The reservoir has a means to remove liquid from the reservoir without permanently removing the liquid from the cell.

Abstract: An electrochemical cell system is disclosed, wherein at least one electrochemical cell is provided in a vessel. The electrochemical cells each include a membrane electrode assembly having a first electrode, a second electrode, and a membrane disposed between and in intimate contact with the first electrode and the second electrode. The vessel is disposed around the membrane electrode assembly. The vessel defines at least a portion of a first storage area that is in fluid communication with the first electrode. Further vessel defines at least a portion of a second storage area that is in fluid communication with the second electrode.

Abstract: An electrolytic cell (40) for the electrowinning of aluminium comprises a plurality of anodes (60) immersed in a molten electrolyte (50), each anode (60) having an oxygen-evolving active surface of open structure facing and spaced by an inter-electrode gap from a cathode (70); a thermal insulating cover (45) above the surface (51) of the molten electrolyte (50); and an alumina feed device (10) arranged above the molten electrolyte surface (51) for spraying and/or blowing alumina (55) to an area of the molten electrolyte surface (51), from where the alumina (55) dissolves as it enters the electrolyte (50) and alumina-rich electrolyte flows to the inter-electrode gaps where it is electrolysed to produce oxygen gas on the anodes (60) and aluminium on the cathode (70).

Abstract: A method of producing aluminum in an electrolytic cell containing alumina dissolved in an electrolyte, the method comprising the steps of providing a molten salt electrolyte at a temperature of less than 900° C. having alumina dissolved therein in an electrolytic cell having a liner for containing the electrolyte, the liner having a bottom and walls extending upwardly from said bottom. A plurality of non-consumable anodes and cathodes are disposed in a vertical direction in the electrolyte, the cathodes having a plate configuration and the anodes having a flat configuration to compliment the cathodes. The anodes contain apertures therethrough to permit flow of electrolyte through the apertures to provide alumina-enriched electrolyte between the anodes and the cathodes. Electrical current is passed through the anodes and through the electrolyte to the cathodes, depositing aluminum at the cathodes and producing gas at the anodes.

Abstract: Conventional aluminum smelting cells are retrofitted with inert anode assemblies which replace the consumable carbon anodes of the cell. The inert anode assemblies may include multiple inert anodes, and may also include insulation for reducing heat loss during operation of the retrofit cells.

Abstract: An integrated tool is provided including at least one workpiece processing station having a paddle assembly. In accordance with one aspect of the invention, the workpiece processing station is adapted for adjusting the level of the processing fluid relative to a workpiece, wherein the portion of the workpiece to be processed and possibly the paddle is selectively immersed within the processing fluid. In accordance with a further aspect of the invention, a paddle is provided for use proximate to a workpiece in a workpiece processing station. The paddle includes a one or more sets of delivery ports and one or more sets of fluid recovery ports. In at least one embodiment, the paddle provides for agitation of a processing fluid proximate to the surface of the workpiece. In at least another embodiment, the paddle provides for the delivery and/or recovery of one or more fluids to the portion of the workpiece to be processed.

Abstract: A fluorine gas generating apparatus for generating fluorine gas of high purity by electrolysis of a mixed molten-salt comprising hydrogen fluoride, the fluorine gas generating apparatus comprising an electrolytic cell which is separated into an anode chamber 5 and a cathode chamber 7 by a partition wall 28, and pressure keeping means 50 for supplying gas to the anode chamber 5 and the cathode chamber 7, respectively, to keep an interior of the anode chamber 5 and an interior of the cathode chamber 7 at a certain pressure.

Abstract: A cell for the electrowinning of aluminium comprising one or more anodes (10), each having a metal-based anode substrate, for instance comprising a metal core (11) covered with an metal layer 12, an oxygen barrier layer (13), one or more intermediate layers (14; 14A, 14B) and an iron layer (15). The anode substrate is covered with an electrochemically active transition metal oxide layer, in particular an iron oxide-based outside layer (16) such as a hematite-based layer, which remains dimensionally stable during operation in a cell by maintaining in the electrolyte a sufficient concentration of iron species and dissolved alumina. The cell operating temperature is sufficiently low so species and dissolved alumina.

Abstract: A system for producing one or more gases for enhancing combustion in an internal combustion engine, the engine having an intake, the system comprising: an electrolysis cell, for generating one or more combustion enhancing gases under pressure; a gas conduit, for connecting the electrolysis cell to the internal combustion engine; and a flow regulator, operatively connected between the electrolysis cell and the intake of the engine, for regulating a flow of the combustion enhancing gases to the engine.

Abstract: A pneumatic control system is provided for selectively controlling movement of a pneumatically-operated device between first and second working positions. The pneumatically-operated device includes a working portion and a pneumatic-control portion. The pneumatic-control portion is in fluid communication with a pressurized fluid source and includes a series of valves for selectively manipulating the working portion between the first and second working positions. The pneumatic-control portion further includes a sensing system for holding the working portion in a static mode by selectively applying system pressure to the working portion. In this manner, a more energy efficient system is provided by eliminating the need for continuous application of full line pressure.

Abstract: An automatic reactant dispenser for use in an electrolysis cell for electrolyzing a reactant product into reactants, the dispenser comprising a container generally surrounding the electrodes with a cover that controls dispensation of a reactant produced at the electrode during electrolysis of the reactant product. In one embodiment, the cover has a plurality of apertures that allow passage of droplets of liquid reactant through the cover. The apertures are spaced on the cover so as to maintain separation of the droplets as they pass through the cover. In another embodiment, the bottom of the cover has a plurality of pockets which collect liquid reactant. Buoyant forces from the accumulated liquid reactant cause the cover to pivot open to release the accumulated liquid reactant. The pivoting of the cover may also temporarily interrupt the electrical circuit energizing the electrodes.

Abstract: A process for repairing a hole in the crust of an electrolytic cell. The hole is repaired by covering it with a receptacle containing solid particles. The receptacle comprises a polymeric material. More preferably, the receptacle comprises a cellulosic material, such as paper, polymer-impregnated paper, or cardboard. A closed paper bag having at least two paper layers and weighing about 15-20 lb. (6.8-9.1 kg) is particularly preferred. When the electrolytic cell produces aluminum by electrolysis of alumina, the solid particles comprise an aluminum compound such as alumina, aluminum fluoride, cryolite, or a mixture of such compounds. Two preferred forms of alumina include smelting grade alumina (SGA) and alumina dust collected by an electrostatic precipitator (ESP dust).

Abstract: A method of producing aluminum in an electrolytic cell containing alumina dissolved in an electrolyte. A plurality of non-consumable anodes are disposed substantially vertically in the electrolyte along with a plurality of monolithic hollow cathodes. Each cathode has a top and bottom and the cathodes are disposed vertically in the electrolyte and the anodes and the cathodes are arranged in alternating relationship. Each of the cathodes is comprised of a first side facing a first opposing anode and a second side facing a second opposing anode. The first and second sides are joined by ends to form a reservoir in the hollow cathode for collecting aluminum therein deposited at the cathode.

Abstract: A non-carbon, metal-based slow-consumable anode of a cell for the electrowinning of aluminium self-forms during normal electrolysis an electrochemically-active oxide-based surface layer (20). The rate of formation (35) of the layer (20) is substantially equal to its rate of dissolution (30) at the surface layer/electrolyte interface (25) thereby maintaining its thickness substantially constant, forming a limited barrier controlling the oxidation rate (35). The anode (10) usually comprises an alloy of iron with at least one of nickel, copper, cobalt or zinc which during use forms an oxide surface layer (20) mainly containing ferrite.

Abstract: An electrolytic cell for the electrowinning of aluminium comprises a cathode cell bottom provided with a series of sloped active cathode surfaces (11, 12) down which produced aluminium (60) is drained, and a series of recessed grooves or channels (20), below the bottom of the cathode active surfaces (11, 12) and extending therealong which collect and evacuate the drained produced aluminum (63). Preferably the active surfaces (11, 12) are V-shaped and the recessed grooves or channels (20) are provided with a sloping bottom and a constant cross-sectional area. Alumina is so fed into the cell as to supply alumina-rich electrolyte (62) into the recessed grooves or channels (20) which contain the alumina-rich electrolyte along substantially their entire length above the drained layer of aluminium (63).

Abstract: A cell for the electrowinning of aluminium comprises a plurality of metal-based anodes facing and spaced apart from an aluminium-wettable drained cathode surface on which aluminium is produced. The drained cathode surface is formed along the cell by upper surfaces of a series of juxtaposed carbon cathode blocks, the cathode blocks extending across the cell. The drained cathode surface is divided into quadrants by a longitudinal aluminium collection groove along the cell and by a central aluminium collection reservoir across the cell. Pairs of quadrants across the cell are inclined in a V-shape relationship, the collection groove being located along the bottom of the V-shape and arranged to collect molten aluminium draining from the drained cathode surface and evacuate it into the aluminium collection reservoir during cell operation.

Abstract: An object of the invention is to provide a sodium refining apparatus which has a simple constitution and does not deteriorate a solid electrolyte employed therein. The sodium refining apparatus of the invention, in which impurities contained in sodium are removed by a solid electrolyte having sodium ion conductivity, includes a bottom-closed casing made of a solid electrolyte and containing a small amount of highly pure sodium; an outer casing accommodating said bottom-closed casing and containing, outside said bottom-closed casing, impurity-containing sodium; a first electrode inserted in the impurity-containing sodium; a second electrode inserted in the highly pure sodium; and a power source for applying DC voltage to the electrodes; wherein the impurity-containing sodium and the highly pure sodium are in electrical contact with each other via the solid electrolyte.

Abstract: The object of the invention is an arrangement of an electrolysis plant for the production of aluminium using the Hall-Heroult process, with which it is possible to limit the pathway length of heavy flows, such as flows of liquid aluminium. According to the invention, the plant comprises: at least one liquid aluminium production zone (H) comprising electrolysis pots arranged in lines, specific operational support zones, including a zone (C) grouping together the supply and recycling installations for anode assemblies, a zone (B) grouping together the supply and recycling installations for electrolysis baths, and a zone (A) grouping together the liquid aluminium processing installations, transport means to convey so-called heavy intermediate products (such as liquid aluminium) between said operational zones, at least one transit zone (101, 102, 103, 104, 105, 106, 110, 111, 112, 113) reserved for all or part of said transport means for the heavy intermediate products.

Abstract: An apparatus for electrolytic production of magnesium includes a plurality of upright anode elements interspread with a plurality of cathode elements situated within at least one electrolysis compartment. At least one section, defined between two adjacent anodes and having an elongated loading inlet, is provided for receiving and melting of a substantially solid raw material. A gas discharging outlet is formed for discharging of chlorine gas developed at the plurality of anodes. A baffle is supported by the receiving anodes in the vicinity of the gas discharging outlet. The baffle prevents direct flow of a mixture of chlorine gas and fine dust particles resulted from loading of the solid raw material between the section and gas discharging outlet.

Abstract: A cell of advanced design for production aluminum by the electrolysis of an aluminum compound dissolve in a molten ectrolyte, has a cathode (30) of drained configuration, and at least one non-carbon anode (10) facing the cathode both covered by the electrolyte (54). The upper part of the cell contains a removable thermic insulating cover (60) placed just above the level of the electrolyte (54). Preferably, the cathode (30) comprises a cathode mass (32) supported by a cathode carrier (31) made of electrically conductive material which serves also for the uniform distribution of electric current feeders (42) which connect the cathode carrier (31) to the negative busbars.

Abstract: A process for preparing sodium and aluminum chloride electrochemically is described in which, in an electrolytic cell containing aluminum as an anode and sodium as a cathode which are separated from one another by a sodium ion-conducting solid electrolyte, a fused electrolyte essentially containing sodium tetrachloroaluminate is electrolyzed in the anode compartment, aluminum chloride formed in this process is evaporated from the electrolytic cell and sodium is removed from the cathode compartment.

Abstract: The invention relates to a method of producing aluminum in an electrolytic cell, particularly in a drained cell, such cell comprising a cathode (20) and facing anodes (10), each anode (10) being spaced apart in its operative position from the cathode (20) by an anode-cathode reduced distance defining an anode-cathode gap containing the bath being electrolyzed. The method comprises: feeding alumina into the electrolyte where it is dissolved; electrolyzing an alumina-rich bath in the anode-cathode gap; and periodically moving at least one anode (10) in order to intake rich-alumina electrolyte into the anode-cathode gap thereby distributing alumina-rich electrolyte under the entire anode surface.

Abstract: An electrolytic cell (40) for the electrowinning of aluminium comprises a plurality of anodes (60) immersed in a molten electrolyte (50), each anode (60) having an oxygen-evolving active surface of open structure facing and spaced by an inter-electrode gap from a cathode (70); a thermal insulating cover (45) above the surface (51) of the molten electrolyte (50); and an alumina feed device (10) arranged above the molten electrolyte surface (51) for spraying and/or blowing alumina (55) to an area of the molten electrolyte surface (51), from where the alumina (55) dissolves as it enters the electrolyte (50) and alumina-rich electrolyte flows to the inter-electrode gaps where it is electrolysed to produce oxygen gas on the anodes (60) and aluminium on the cathode (70).

Abstract: There is disclosed an electroplating bath for depositing zinc/manganese alloys on a substrate characterized in that it comprises an aqueous bath free or substantially free of ammonium halide and of fluoroborate which is made up from 10-150 g/l, alkali metal salt, 30-90 g/l boric acid, 10-200 g/l water soluble zinc salt, 10-50 g/l water soluble manganese salt, 60-140 g/l alkali metal gluconate or tartrate and a base e.g. an alkali metal hydroxide to bring the pH to the range 6.1-7.1.

Abstract: An electrolytic bath for use during the electrolytic reduction of alumina to aluminum. The bath comprises molten electrolyte having the following ingredients: AlF3 and at least one salt selected from the group consisting of NaF, KF, and LiF; and about 0.004 wt. % to about 0.2 wt. %, based on total weight of the molten electrolyte, of at least one transition metal or at least one compound of the metal or both. The compound is, a fluoride; oxide, or carbonate. The metal is nickel, iron, copper, cobalt, or molybdenum. The bath is employed in a combination including a vessel for containing the bath and at least one non-consumable anode and at least one dimensionally stable cathode in the bath. Employing the instant bath during electrolytic reduction of alumina to aluminum improves the wetting of aluminum on a cathode by reducing or eliminating the formation of non-metallic deposits on the cathode.

Abstract: A dimensionally stable electrode is provided comprising a hollow substrate with an open upper end for confining a fluid containing a metal, a film covering portions of the external surface; and a mechanism for replenishing the film. Also provided is a method for maintaining the dimensions of an anode during electrolysis comprising adapting an interior surface of the anode to receive a fluid containing a metal, facilitating transport of the metal to an exterior surface of the anode, forming a protective film on the exterior surface, wherein the transported metal is a cation of the formed protective film, and maintaining the protective film on the exterior surface while the anode is in use.