Abstract: A system for hooding an electrolytic cell used in the production of aluminum comprises a plurality of aluminum hoods supported on the anode rods of the cell. The anode rods are provided with a plurality of cams projecting out of the sides thereof parallel to the anode pins for supporting the hoods. The hoods are provided with a cut-out opening for receiving the anode rod.

Abstract: An improved cell is disclosed for producing metal by electrolytic reduction of a metal halide in a molten bath comprising the metal halide dissolved in at least one molten halide of higher electrodecomposition potential than the metal halide. The cell includes an inner refractory lining and a plurality of electrodes which are located adjacent to and in abutment with the lining. The electrodes are disposed generally horizontally and arranged in at least one vertical stack. The electrodes in each stack are located beneath the upper level of the bath, and are arranged in a superimposed, spaced relationship defining inter-electrode spaces between each pair of adjacent electrodes. The cell also includes a vertical gas-lift passage associated with each stack of electrodes, which is in fluid communication with each inter-electrode space in the stack.

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: 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: In an electrolysis cell, molten alkali hydroxide is decomposed into products which include alkali metal and water. The water dissolves in the electrolyte where it is decomposed by electrolysis or by reaction with alkali metal thereby reducing efficiency of the cell and yield of the alkali metal.According to the process of the invention, the electrolyte with water dissolved therein is drawn through openings in an anode, is depleted of the dissolved water by a dehydrating means which is separate from the cell, and the dehydrated electrolyte is returned to an anolyte portion of the operating electrolysis cell for further decomposition.According to the apparatus of the invention, the anode comprises a plurality of parallel elongated electrodes which alternate with parallel channels. The electrolyte flows from a return channel, over an electrode, and through a withdrawal channel for the depletion of water and return to operating portions of the electrolysis cell through the return channels.

Abstract: A cap for the access port of the dome of a fused salt electrolytic cell comprising a circular cap body (1) having an outer flange (2) and a sealing surface (3) on its bottom, attached to the sealing surface an inner ring (4) concentric with the outer flange and with the flange defining a circular groove (5) within which the top of an access port (6) fits, within the groove a resilient refractory packing (7) that provides a seal between the top of the access port and the sealing surface.

Abstract: The present invention provides an apparatus for electrolytic production of magnesium metal from its chloride, which apparatus essentially comprises at least one externally unwired electrode which is made of graphite alone or graphite-iron composite and is placed between each pair of anode and cathode with the graphite side towards the cathode. The apparatus preferably comprises further a cooling passage for electrolyte bath which allows the electrolyte bath to flow outside an electrolysis chamber where the electrodes are contained, from a bath surface level to the bottom. The bath, while it passes there, is cooled a little, not enough to solidify, to exhibit an increased density so that it flows down back into the electrolysis chamber at the bottom, thus forming a continuous upflow along the electrodes, which facilitates separation of products of magnesium metal and chlorine gas and their recovery. Preferred anode construction is also illustrated.

Abstract: Magnesium is electrolytically produced from a salt melt comprising magnesium chloride by the use of an electrolyzer having at least one electrolysis compartment and at least one metal separating compartment separated from the electrolysis compartment by a partition wall. Magnesium chloride is fed in solid form in a direction counter current to the flow of chlorine gas liberated during electrolysis to a melting room or chamber in the electrolysis compartment arranged such that contact between the magnesium chloride and the anodes of the electrolyzer is avoided. Flow patterns are produced in the melt to ensure that sludge forming impurities in the fed magnesium chloride are continuously removed from the electrolysis compartment to the metal separating compartment.

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: An apparatus for producing hydrogen and oxygen or oxides wherein electrolysis of an aqueous system is carried out using, in the cathode compartment of the electrolysis cell, a hydride-forming liquid metal, the resulting hydride being thermally decomposed to produce the hydrogen.

Abstract: It has been known that metals of groups IV-B, V-B, and VI-B of the periodic table, namely chromium, hafnium, molybdenum, niobium, tantalum, titanium, tungsten, vanadium, and zirconium and alloys thereof can be electrodeposited as dense, structurally coherent plates from a solution of the refractory metal fluoride in a molten alkali-flouride mixture in which the concentration of oxygen is reduced to and maintained at the sufficiently low level. It is shown that niobium may be plated at a lower temperature and a higher rate when the oxygen concentration is reduced to lower levels than previously attainable.

Abstract: An improved aluminum reduction cell which includes an insulated container for the molten electrolyte, a cover over the open mouth of the container, and a heat exchanger positioned above the molten bath, within the container and below the cover for recovering heat from the molten bath and further including, in one embodiment, means for converting the recovered heat into electricity which can be recycled back to the reduction cell. By heavily insulating the reduction cell against heat loss and by appropriately controlling the amount of heat which is recovered the cell can be operated over a wide range of electrical power inputs.

Abstract: The covering sytem for a conventional fused salt electrolytic cell for the reduction of aluminum oxide to metallic aluminum comprises individual lids (4) butting onto each other at the sides and inclined downwards from the anode beam (1) to the edges (5) of the long sides of the reduction pot. The lids (4) are provided with a support (6) which rests on a rail (13) when the anode beam is in the raised position. As the anode beam (1) is lowered, the lids (4) slide over the long edges (5) of the pot, until they are supported by the stops (7) mounted on the lower third part of the lid (4). On lowering the beam (1) further, the supports (6) slide on the anode beam (1). The anode rods (2) are enclosed at the sides by the lids (4).

Abstract: An electrolytic cell is provided for the electrochemical separation of selected metals from electrodissociatable compounds thereof in the molten state utilizing as electrode separator a plurality of solid electrolyte tubes which, under the influence of an electrical potential, are permeable to the flow of selected cations, but impermeable to fluids and the flow of anions and other cations. Means are provided with each tube for detecting the flow of molten metal from each solid electrolyte tube to a molten metal collection zone associated with the cell.

Abstract: The present invention provides a highly efficient reduction cell hood which utilizes an improved shield installation which is easily movable by hand thereby allowing for fewer shields which results in a corresponding decrease in the number of joints which must be sealed. The reduction cell hood of the present invention is constructed of a material which is capable of withstanding the operating temperatures of the electrolyte process without warping, buckling or other damage thereto.

Abstract: Metal such as aluminum is produced electrolytically from metal chlorides or other halides dissolved in a molten solvent bath of higher decomposition potential in a cell including one or more graphite cathode surfaces spaced from opposed anodes, particularly a bipolar cell, with bath flow through the spaces between the anodes and cathodes. The wetting characteristics of the carbonaceous cathode with respect to the metal deposited there by electrolysis are selectively balanced with the bath flow over the cathode and with the anode-to-cathode distance. Cathode surface wear rate is substantially reduced if the surface is wettable by the metal in regions of low bath flow velocity or regions of greater anode-cathode distance. The wear rate is also reduced by using non-wettable cathode surfaces in regions of higher bath flow velocity or regions of closer anode-cathode distance.

Abstract: In the scrubbing of gases containing sorbable contaminants, particularly the waste gases from reduction cells for electrolytic production of aluminium the waste gas is injected tangentially into the bottom of a cylindrical chamber, from which it is withdrawn through an axial outlet passage at the top end. A solid sorbent material is introduced into the chamber at one or more positions at the top end of the chamber in such a way that it enters the ascending gas stream in a peripheral zone of the chamber.

Abstract: An electrolyte and process for the low temperature industrial electrolytic production of fluorine gas utilizing a ternary electrolyte having a composition of:NH.sub.4 F=5 to 20 mol % of NH.sub.4 +KFHF=40 to 45%, by weight, of NH.sub.4 F+KF+HFwherein the working temperature of the electrolyte is maintained between about 50.degree. C. and about 75.degree. C.

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 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: An electroplating apparatus for applying a protecting metallic coating on the surface of a workpiece, the apparatus featuring a process chamber for containing an electrolytic solution, and means for leading an electric current to the workpiece and to the solution. A pneumatic pressure reducing pump is further provided for creating subatmospheric pressure about said process chamber and the spaces containing said electrolytic solution which is in communication with the electrolytic solution in the process chamber, whereby the use of a high electrical current density during electroplating is possible.

Abstract: An aluminum electrolytic cell wherein, in a sealed type electrolytic cell having a raw material aluminum chloride feeding port and chlorine gas discharging ports in a top section and a molten metal reservoir in a bottom section and provided with an electrode element in the intermediate section so that a molten salt electrolytic bath containing aluminum chloride is electrolyzed in the cell and molten aluminum is collected from the metal reservoir in the bottom section, the electrode element is formed of funnel-shaped electrodes laminated at a fixed distance between the electrodes or a pair of right and left electrode plate groups opposed to each other at a fixed separation between them and inclined to be lower inward at least one intermediate bi-polar electrode is provided between both cathode and anode and a gas rising passage is formed between the outer edges of the funnel-shaped electrodes or the electrode plates and inner wall of the cell to prevent the rechlorination of the aluminum after electrolysis.

Abstract: An apparatus for filling an anode paste in an anode hole formed when an anode contact stud is pulled out from the anode of a vertical Soderberg aluminum electrolytic cell comprises horizontally moveable anode paste charging arm with an anode paste conveying means and a hopper for storing the anode paste and feeding the paste to the anode paste charging arm when required, the arm and the hopper being provided at a support movable along the electrolytic cell.

Abstract: A method for producing metal by electrolysis in a molten salt bath containing superimposed electrodes, at least one of which is a bipolar electrode. The arrangement of the electrodes creates interelectrode spaces between them. Bath is swept through these interelectrode spaces. This method is improved by providing circulation of the bath from one interelectrode space to the next at a location inwards of the outer peripheries of the electrodes. This can be accomplished e.g. by boring holes through the electrodes. It can also be accomplished by breaking the electrodes into individual, mutually separated stacks of electrodes, the circulation of the improvement then occurring e.g. in the space between the stacks.

Abstract: A new electrolyzer for the industrial production of fluorine gas which uses bipolar and monopolar electrodes within a tank containing an electrolyte of an anhydrous mixture of mineral fluorides and hydrogen fluoride. A compact construction is achieved which requires only two current connections.

Abstract: A cell for fused-salt electrolysis for reducing alumina in the presence of cryolite to metallic aluminum. The cell includes an insulated tank having a carbon bottom, two rows of anode rods disposed on opposite sides of an anode carrier positioned in the longitudinal center plane, an exhaust gas-collecting duct extending at the longitudinal center between the two rows of anode and covers downwardly inclined from the outside of respective rows of anode rods to respective edges of the tank and provided at the outer longitudinal edge and the transverse edges with a skirt that extends to the respective edge of the tank. Each cover is hinged adjacent to its longitudinal edge adjacent to the anodes and at least at its corner portions to a support which extends along the row of anode rods. A carrying arm is secured to each end portion of the support and is pivoted at its other end to the anode carrier.

Abstract: An electrolytic cell is provided for the electrochemical separation of selected metals from electrodissociatable compounds thereof in the molten state utilizing as electrode separator a plurality of solid electrolyte tubes which, under the influence of an electrical potential, are permeable to the flow of selected cations, but impermeable to fluids and the flow of anions and other cations. Electrical switching means are provided with each tube for starting and stopping production of molten metal therein, and for providing a removable electrical path between a cathodic element of the cell and the molten metal in each tube.

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: 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 method for exhausting a substance through a port in a lid of a chamber, comprising conducting the substance through a tube within the port, which tube is more resistant to corrosion by the substance than is the port, and supporting the tube on a support means extending into the interior of the port, while cooling the support means to a temperature such that it too is more resistant to corrosion by the substance than is the port.A cell lid having a metallic port, metallic protrusion means extending into the port, cooling means for extracting heat from the protrusion means, and a carbon or ceramic tube supported on the protrusion means.

Abstract: An electrolytic cell for the electrochemical separation of selected metals from electrodissociatable compounds thereof in the molten state utilizing as electrode separator a plurality of solid electrolyte tubes which, under the influence of an electrical potential, are permeable to the flow of selected cations, but impermeable to fluids and the flow of anions and other cations.

Abstract: Magnesium is produced by decomposition of magnesium chloride contained in an electrolyte. The magnesium chloride containing electrolyte is provided in a refractory lined electrolytic cell having an anode and a cathode wherein magnesium is produced at the cathode and chlorine at the anode, the magnesium accumulating in a layer on the surface of the electrolyte. A shroud having a skirt portion therein formed from a nitride-based refractory projects into the electrolyte such that chlorine produced at the anode is removed from the cell without contacting the molten magnesium layer, the shroud being resistant to attack by molten magnesium, electrolyte and gases emanating therefrom.

Abstract: The electrolyzer has a refractory-lined hollow shell divided into a group of electrolytic cells and a magnesium collecting cell by a vertical separator plate that is shorter than the shell. Steel cathodes shaped as frames embrace a graphite anodes arranged in groups. To convey magnesium from the electrolytic cells into a magnesium collecting cell, at least two passageways are provided, each of them being substantially at right angles to the graphite anodes and to the separator plate. The separator plate has through perforations situated below the electrolyte level. Each of the passageways is confined between the wall of the electrolyzer shell and the portion of the cathode that faces towards the magnesium collecting cell. The width of each of the magnesium conveyance passageways is a maximum of three times the width of the gap across the adjacent graphite anode and steel cathode in each electrolytic cell.

Abstract: The cell has a lateral enclosure constructed of alternately overlapping panels arranged to provide access selectively at each anode position of the cell.

Abstract: A gas collection apparatus for use in electrical smelting furnaces especially those for the production of aluminum is disclosed. The apparatus comprises a substantially annular body positioned beyond the outer circumference of the furnace at its lower edge and tapering towards the anode carrier at its upper edge. A space at the bottom is left between the wall of the gas collection apparatus and the furnace to permit introduction of air resulting in a chimney effect in the gas collecting apparatus of the present invention.

Abstract: Hydrogen-fluoride-containing gases from the electrolytic production of aluminum are subjected to electrostatic precipitation to remove dust particles containing substances which are deleterious to aluminum production before the gases are treated in an expanded bed with alumina on which the hydrogen fluoride is adsorbed. Following the dry adsorption in the expanded bed, the gases entraining the adsorbent particles are subjected to electrostatic precipitation in which the particles are separated from the gas thus freed from hydrogen fluoride. The particles are recycled to the electrolytic aluminum production apparatus, the particles being free from the deleterious substances which have previously been removed.

Abstract: The invention relates to a process and an apparatus for collecting the fumes given off during the production of aluminium in an electrolysis cell with a continuous anode.In the process, the surface of the elecytrolysis bath is closed, on the one hand along the long sides of the cell, by a longitudinal panel which is applied in fluid-tight manner to the anode tube, leaving an air intake free at its base, and on the other hand along the short sides of the cell by a fixed hooding closed laterally by the longitudinal panel.The invention is applicable to cells for the igneous electrolysis of alumina comprising a continuous anode.

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 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: A gas collection apparatus for use in electrical smelting furnaces, especially those for the production of aluminum is disclosed. The apparatus comprises a substantially annular body positioned beyond the outer circumference of the furnace at its lower edge and tapering towards the anode carrier at its upper edge. A space at the bottom is left between the wall of the gas collection apparatus and the furnace to permit introduction of air resulting in a chimney effect in the gas collecting apparatus of the present invention.