Utilizing Specified Electrode Other Than Consumable Electrode (e.g., Cylindrical, Tapered, Etc.) Patents (Class 205/380)
  • Patent number: 10505083
    Abstract: Methods for fabricating a semiconductor devices, and in particular light emitting diodes (LEDS) comprising providing a plurality of semiconductor devices on a substrate and forming a contact on at least some of the semiconductor devices. A containment structure is formed on at least some of the semiconductor devices having a contact with each containment structure defining a deposition area excluding the contact. A coating material is deposited then within the deposition area, with the coating material not covering the contact. A light emitting diode (LED) chip wafer comprising a plurality of LEDs on a substrate wafer with at least some of the LEDs having a contact. A plurality of containment structures are included, each of which is associated with a respective one of the plurality of LEDs. Each of the containment structures at least partially on its respective one of the LEDs and defining a deposition area on its respective one of the LEDs. The deposition area excludes the contact.
    Type: Grant
    Filed: July 11, 2007
    Date of Patent: December 10, 2019
    Assignee: CREE, INC.
    Inventors: James Ibbetson, Kristi Wong, Maryanne Becerra
  • Patent number: 9401461
    Abstract: A light emitting diode is disclosed, together with associated wafer structures, and fabrication and mapping techniques. The diode includes an active portion, a raised border on the top surface of the active portion and around the perimeter of the top surface of the active portion, a resin in the space defined by the border and the top surface of the active portion, and phosphor particles in the resin that convert the frequencies emitted by the active portion.
    Type: Grant
    Filed: July 11, 2007
    Date of Patent: July 26, 2016
    Assignee: CREE, INC.
    Inventors: Peter S. Andrews, Joshua J. Markle, Ronan P. Le Toquin
  • Patent number: 8097144
    Abstract: A cell for the electrowinning of aluminium has a cavity for containing electrolyte (20) and one or more non emerging active anode bodies (5) that are suspended in the electrolyte. The electrolyte's surface (21,21?) has an expanse extending over the cavity and is substantially covered by a self-formed crust (25) of frozen electrolyte. The crust is mechanically reinforced by at least one preformed refractory body (30, 30?,30?). The electrolyte crust is formed against the preformed refractory body and bonded thereto so as to inhibit mechanical failure of the crust and collapse of the crust into the cavity.
    Type: Grant
    Filed: February 26, 2007
    Date of Patent: January 17, 2012
    Assignee: Rio Tinto Alean International Limited
    Inventors: Thinh T. Nguyen, René Von Kaenel, Vittorio De Nora
  • Patent number: 7935241
    Abstract: A slurry comprises suspended aluminum particles in a colloid having dispersed colloidal particles of a metal oxide such as a hydroxide. The metal oxide is reducible by metallic aluminum. The slurry has such a basic pH that dissolution of the aluminum particles in the slurry is inhibited so that when the slurry is subjected to a heat treatment, the undissolved aluminum particles are reactable with the colloidal particles to form an aluminum-based mixture resistant to chemical attack made of aluminum oxide, metal aluminum and the metal of the colloidal particles. The slurry can be used to form an aluminum-based protective coating on a component, in particular of an aluminum electrowinning cell or an apparatus for treating molten aluminum.
    Type: Grant
    Filed: March 6, 2006
    Date of Patent: May 3, 2011
    Assignee: Rio Tinto Alcan International Limited
    Inventors: Thinh T. Nguyen, Vittorio De Nora
  • Patent number: 7901560
    Abstract: A method of producing aluminium in a Hall-Héroult cell with prebaked anodes, as well as anodes for the same. The anodes are provided with slots in a wear (bottom) surface thereof for gas drainage. The slots are 2-8 millimeters wide, and preferably 3 millimeters.
    Type: Grant
    Filed: June 9, 2006
    Date of Patent: March 8, 2011
    Assignee: Norsk Hydro ASA
    Inventor: Arild Storesund
  • Publication number: 20090127126
    Abstract: Current busbar for anode or cathode for use in production of aluminium from alumina in an electrolysis bath in an electrolysis cell, comprising ends or sections that during operation shall be within the electrode body are formed as horizontally oriented conical bodies and cylindrical or conical grooves with largest horizontal cross section dimension within said grooves, such that by sliding in correspondingly formed cooper rails on the external parts of the busbar, said bodies and rails are releasable joined.
    Type: Application
    Filed: February 16, 2005
    Publication date: May 21, 2009
    Inventor: Stig Torvund
  • Patent number: 7504010
    Abstract: The present invention relates to a dimensionally stable oxygen-evolving anode for use in an electrolytic cell for the production of aluminium. The anode comprises of a container made from an alloy comprising aluminium and at least one metal more noble than aluminium; a fluid bath in the bottom of the container having the ability to dissolve aluminium, said fluid having a density that is higher than the density of molten aluminium at the operating temperature of the cell, a pool of molten aluminium floating on top of the fluid bath in the bottom of the container; a refractory layer arranged on the inner sidewalls of the container at least in the area of the pool of molten aluminium, said refractory layer protecting the molten aluminium from contacting the inner sidewalls of the container.
    Type: Grant
    Filed: March 9, 2006
    Date of Patent: March 17, 2009
    Assignee: Elkem AS
    Inventors: Jan Arthur Aune, Georg Frommeyer, Kai Johansen, Donald R. Sadoway, Gro Soleng, Elke William Thisted
  • Patent number: 7077945
    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.
    Type: Grant
    Filed: May 8, 2003
    Date of Patent: July 18, 2006
    Assignee: Northwest Aluminum Technologies
    Inventors: S. Craig Bergsma, Craig W. Brown, Donald R Bradford, Robert J. Barnett, Michael B. Mezner
  • Patent number: 7033469
    Abstract: Ceramic inert anodes useful for the electrolytic production of aluminum are disclosed. The inert anodes comprise oxides of Ni, Fe and Al. The Ni—Fe—Al oxide inert anode materials have sufficient electrical conductivity at operation temperatures of aluminum production cells, and also possess good mechanical stability. The Ni—Fe—Al oxide inert anodes may be used to produce commercial purity aluminum.
    Type: Grant
    Filed: November 8, 2002
    Date of Patent: April 25, 2006
    Assignee: Alcoa Inc.
    Inventors: Douglas A. Weirauch, Jr., Joseph M. Dynys, Robert A. DiMilia, Siba P. Ray, Xinghua Liu, Frankie E. Phelps
  • Patent number: 6866766
    Abstract: Methods and apparatus are disclosed for reducing sulfur impurities in aluminum electrolytic production cells in order to significantly increase current efficiency of the cells. An impurity reduction zone may be created in the bath of an inert anode cell by submerging a purifying electrode in the bath. In another embodiment, an oxygen barrier tube may be disposed in a portion of the bath. In a further embodiment, reductants such as aluminum, CO and/or CO2 are added to the bath. In another embodiment, electrode current is interrupted or electrodes are removed from selected regions of the cell in order to allow gaseous impurities to escape from the bath. Sulfur impurity levels may also be reduced in inert anode cells by scrubbing bath emissions from the cell before they are reintroduced into the cell, and by controlling sulfur impurity contents of materials added to the cell.
    Type: Grant
    Filed: August 5, 2002
    Date of Patent: March 15, 2005
    Assignee: Alcoa Inc.
    Inventors: Alfred F. LaCamera, Siba P. Ray, Xinghua Liu, Robert L. Kozarek, Jerry L. Roddy
  • Patent number: 6855234
    Abstract: A sintered electrode assembly is made of an inert electrode (15) containing a sealed metal conductor (20) having a surface feature (30) such as a coating or wrapping which aids in bond formation with the inert electrode (15) at their interface (45), where the metal conductor (20) is directly contacted by and is substantially surrounded by the inert electrode (15) without the use of metal foam or metal powders.
    Type: Grant
    Filed: April 2, 2003
    Date of Patent: February 15, 2005
    Assignee: Alcoa Inc.
    Inventor: Leroy E. D'Astolfo, Jr.
  • Patent number: 6811676
    Abstract: An electrolytic cell for producing aluminum from alumina having a reservoir for collecting molten aluminum remote from the electrolysis.
    Type: Grant
    Filed: July 16, 2002
    Date of Patent: November 2, 2004
    Assignee: Northwest Aluminum Technologies
    Inventors: Donald R Bradford, Robert J. Barnett, Michael B. Mezner
  • Patent number: 6800191
    Abstract: A method of producing aluminum in an electrolytic cell containing alumina dissolved in an electrolyte, the method comprising providing a molten salt electrolyte having alumina dissolved therein in an electrolytic cell. A plurality of anodes and cathodes having planar surfaces are disposed in a generally vertical orientation in the electrolyte, the anodes and cathodes arranged in alternating or interleaving relationship to provide anode planar surfaces disposed opposite cathode planar surfaces, the anode comprised of carbon. Electric current is passed through anodes and through the electrolyte to the cathodes depositing aluminum at the cathodes and forming carbon containing gas at the anodes.
    Type: Grant
    Filed: March 15, 2002
    Date of Patent: October 5, 2004
    Assignee: Northwest Aluminum Technologies
    Inventors: Robert J. Barnett, Michael B. Mezner, Donald R Bradford
  • Publication number: 20040178079
    Abstract: The invention relates to an arrangement of anode for utilisation in an electrolysis cell for production of aluminium metal from an aluminium containing component in a molten salt electrolyte, in which the aluminium containing component mainly is alumina and the molten salt electrolyte is based on mixtures of NaF and AIF3 and CaF2, and possibly alkaline and alkaline earth halides. More specific it relates to improvements of anodes useful for retrofit of existing electrolysis cells, in which the anodes remains inert during operation. The anode is characterised by being shaped in a manner to increase the area of the electroactive surface. Several examples of such designs are shown. The anode is useful for utilisation in retrolit of existing electrolysis cells of Hall-Hèroult design for aluminium production.
    Type: Application
    Filed: January 20, 2004
    Publication date: September 16, 2004
    Inventors: Stein Julsrud, Ole-Jacob Siljan
  • Patent number: 6783656
    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.
    Type: Grant
    Filed: April 27, 2002
    Date of Patent: August 31, 2004
    Assignee: MoltechInvent S.A.
    Inventors: Vittorio De Nora, Jean-Jacques Duruz
  • Patent number: 6758991
    Abstract: Ceramic inert anodes useful for the electrolytic production of aluminum are disclosed. The inert anodes comprise an oxide of Ni and Fe having a controlled Ni/(Ni+Fe) mole ratio which results in a single-phase structure at the operation temperatures of aluminum production cells. The Ni and Fe oxide material may also have a single-phase structure at the sintering temperature of the material. The single-phase inert anode materials maintain sufficient electrical conductivity at the operating temperatures of the cell, and also possess good mechanical stability.
    Type: Grant
    Filed: November 8, 2002
    Date of Patent: July 6, 2004
    Assignee: Alcoa Inc.
    Inventors: Robert A. DiMilia, Joseph M. Dynys, Douglas A. Weirauch, Jr., Siba P. Ray, Xinghua Liu, Frankie E. Phelps
  • Patent number: 6723212
    Abstract: This cathode (3) contains, within the pores in its structure, a carbon-containing product fired at a temperature of less than 1600° C., improving the erosion resistance by protecting the graphitized binder.
    Type: Grant
    Filed: November 19, 2001
    Date of Patent: April 20, 2004
    Assignee: Carbone Savoie
    Inventors: Regis Paulus, Jean-Michel Dreyfus
  • Publication number: 20040016639
    Abstract: An electrolytic cell for the reduction of aluminum having a layer of interlocking cathode tiles positioned on a cathode block. Each tile includes a main body and a vertical restraining member to prevent movement of the tiles away from the cathode block during operation of the cell. The anode of the electrolytic cell may be positioned about 1 inch from the interlocking cathode tiles.
    Type: Application
    Filed: July 29, 2002
    Publication date: January 29, 2004
    Inventors: Alton T. Tabereaux, Guy L. Fredrickson, Eric Groat, Thomas Mroz, Alan Ulicny, Mark F. Walker
  • Patent number: 6682643
    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.
    Type: Grant
    Filed: October 16, 2001
    Date of Patent: January 27, 2004
    Assignee: Moltech Invent S.A.
    Inventor: Vittorio de Nora
  • Publication number: 20030221970
    Abstract: An anode of a cell for the electrowinning of aluminium comprises a nickel-iron alloy substrate having a nickel metal rich outer portion with an electrolyte pervious integral nickel-iron oxide containing surface layer which adheres to the nickel metal rich outer portion of the nickel-iron alloy and which in use is electrochemically active for the evolution of oxygen. The oxide surface layer has a thickness such that, during use, the voltage drop therethrough is below the potential of dissolution of nickel-iron oxide. The nickel metal rich outer portion may contain cavities some or all of which, after oxidation, are partly or completely filled with iron oxides to form iron oxide containing inclusions.
    Type: Application
    Filed: June 3, 2002
    Publication date: December 4, 2003
    Inventors: Vittorio de Nora, Jean-Jacques Duruz
  • Patent number: 6656340
    Abstract: A cell of advanced design for the production of aluminium by the electrolysis of an aluminium compound dissolved in a molten electrolyte, 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 to the cathode mass (32) from current feeders (42) which connect the cathode carrier (31) to the negative busbars.
    Type: Grant
    Filed: June 4, 2002
    Date of Patent: December 2, 2003
    Assignee: Moltech Invent S.A.
    Inventors: Vittorio de Nora, Jainagesh A. Sekhar
  • Patent number: 6638412
    Abstract: A method of inhibiting dissolution of a transition metal alloy anode (40) of an aluminium electrowinning cell comprises providing a sodium-inert layer (11,20,50,50′) on a sodium-active cathodic cell material (15), such as carbon, and electrolysing alumina dissolved in a sodium ion-containing molten electrolyte (30). Aluminium ions rather than sodium ions are cathodically reduced on the sodium-inert layer to inhibit the presence in the molten electrolyte (30) of soluble cathodically-produced sodium metal that constitutes an agent for chemically reducing the anode's transition metal oxides and anodically evolved oxygen, thereby inhibiting reduction of the anode's transition metal oxides by sodium metal and maintaining the evolved oxygen at the anode at a concentration such as to produce at the alloy/oxide layer interface stable and coherent transition metal oxides having a high level of oxidation.
    Type: Grant
    Filed: March 30, 2002
    Date of Patent: October 28, 2003
    Assignee: Moltech Invent S.A.
    Inventors: Vittorio De Nora, Jean-Jacques Duruz
  • Patent number: 6627062
    Abstract: In this cathode, which is a single block, the electrical resistivity is heterogeneous along its longitudinal axis, this resistivity being higher in the end regions of the cathode (3) than in the central region of the latter.
    Type: Grant
    Filed: October 5, 2001
    Date of Patent: September 30, 2003
    Assignee: Carbone Savoie
    Inventor: Jean-Michel Dreyfus
  • Publication number: 20030173227
    Abstract: A method of producing aluminum in an electrolytic cell containing alumina dissolved in an electrolyte, the method comprising providing a molten salt electrolyte having alumina dissolved therein in an electrolytic cell. A plurality of anodes and cathodes having planar surfaces are disposed in a generally vertical orientation in the electrolyte, the anodes and cathodes arranged in alternating or interleaving relationship to provide anode planar surfaces disposed opposite cathode planar surfaces, the anode comprised of carbon. Electric current is passed through anodes and through the electrolyte to the cathodes depositing aluminum at the cathodes and forming carbon containing gas at the anodes.
    Type: Application
    Filed: March 15, 2002
    Publication date: September 18, 2003
    Inventors: Robert J. Barnett, Michael B. Mezner, Donald R. Bradford
  • Patent number: 6607657
    Abstract: Carbon-containing components of cells for the production of aluminium by the electrolysis of alumina dissolved in a cryolite-based molten electrolyte are protected from attack by liquid and/or gaseous components of the electrolyte in the form of elements, ions or compounds, by a refractory boride coating applied from a slurry composed of pre-formed particulate refractory boride in a colloidal carrier which is dried and heated to consolidate the coating.
    Type: Grant
    Filed: July 25, 2001
    Date of Patent: August 19, 2003
    Assignee: Moltech Invent S.A.
    Inventors: Vittorio de Nora, Jainagesh A. Sekhar
  • Patent number: 6585879
    Abstract: A solid cryolite/alumina mixture is used as the anode in an electrolytic aluminum winning process. The mixture may be used in the form of a crust formed on the electrolytic cell.
    Type: Grant
    Filed: August 15, 2001
    Date of Patent: July 1, 2003
    Inventor: Ersan Ilgar
  • Publication number: 20030106803
    Abstract: A refractory boride body or coating made of a boride of titanium, chromium, vanadium, ziconium, hafnium, niobium, tantalum, molybednum and cerium is produced from a slurry of the refractory boride or a precursor in a collidal carrier preferably composed of two more different grades of the same colloidal carrier selected from colloidal alumina, yttria, ceria, thoria, zirconia, magnesia, lithia, monoaluminum phosphate and cerium acetate. The slurry can also comprise an organic additive selected from polyvinyl alcohol; polyacrylic acid; hydroxyy propyl methyl cellulose; polythylene glycol; ethylene glycol, butyl benzyl phthalate; ammonium polymethacrylate and mixtures thereof. The retractory boride body or coated body is useful as a component of aluminum electrowinning cells.
    Type: Application
    Filed: June 27, 2002
    Publication date: June 12, 2003
    Inventors: Jainagesh Akkaraju Sekhar, Jean-Jacques Duruz, James Jeng Liu
  • Patent number: 6572757
    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).
    Type: Grant
    Filed: October 16, 2001
    Date of Patent: June 3, 2003
    Assignee: Moltech Invent S.A.
    Inventors: Vittorio de Nora, Georges Berclaz
  • Patent number: 6562224
    Abstract: A method of manufacturing an anode for use in a cell for the electrowinning of aluminium comprises oxidising before cell operation an iron-nickel alloy substrate in an oxygen-containing atmosphere, such as air, at a temperature which is at least 50° C., preferably 100° C., above the operating temperature of the cell to form on the surface of the iron-nickel substrate a coherent and adherent iron oxide-containing outer layer, in particular a hematite-containing layer having a limited ionic conductivity for oxygen ions and acting as a partial barrier to monoatomic oxygen. The outer layer is electrochemically active for the oxidation of oxygen ions and reduces also diffusion of oxygen to the iron-nickel alloy substrate when the anode is in use.
    Type: Grant
    Filed: January 29, 2001
    Date of Patent: May 13, 2003
    Assignee: Moltech Invent S.A.
    Inventors: Olivier Crottaz, Jean-Jacques Duruz
  • Patent number: 6558525
    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.
    Type: Grant
    Filed: March 1, 2002
    Date of Patent: May 6, 2003
    Assignee: Northwest Aluminum Technologies
    Inventors: Donald R. Bradford, Robert J. Barnett, Michael B. Mezner
  • Publication number: 20030075454
    Abstract: A method of inhibiting dissolution of a transition metal alloy anode (40) of an aluminium electrowinning cell comprises providing a sodium-inert layer (11,20,50,50′) on a sodium-active cathodic cell material (15), such as carbon, and electrolysing alumina dissolved in a sodium ion-containing molten electrolyte (30). Aluminium ions rather than sodium ions are cathodically reduced on the sodium-inert layer to inhibit the presence in the molten electrolyte (30) of soluble cathodically-produced sodium metal that constitutes an agent for chemically reducing the anode's transition metal oxides and anodically evolved oxygen, thereby inhibiting reduction of the anode's transition metal oxides by sodium metal and maintaining the evolved oxygen at the anode at a concentration such as to produce at the alloy/oxide layer interface stable and coherent transition metal oxides having a high level of oxidation.
    Type: Application
    Filed: March 30, 2002
    Publication date: April 24, 2003
    Inventors: Vittorio De Nora, Jean-Jacques Duruz
  • Publication number: 20030070937
    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 that the required concentration of iron species in the electrolyte (5) is limited by the reduced solubility of iron species in the electrolyte at the operating temperature, which consequently limits the contamination of the product aluminium by iron to an acceptable level.
    Type: Application
    Filed: November 25, 2002
    Publication date: April 17, 2003
    Inventors: Jean-Jacques Duruz, Vittorio De Nora, Olivier Crottaz
  • Patent number: 6540887
    Abstract: A cell for the electrowinning of aluminium comprises at least one non-carbon metal-based anode (10) having an electrically conductive metallic structure (12, 13, 15) which is suspended substantially parallel to a facing cathode (20, 21, 22). Such metallic structure (12, 13, 15) comprises a series of parallel horizontal anode members (15), each having an electrochemically active surface (16) on which during electrolysis oxygen is anodically evolved. The electrochemically active surfaces (16) are in a generally coplanar arrangement to form the active anode surface. The anode members are spaced apart from one another by inter-member gaps forming flow-through openings (17) for the circulation of electrolyte (30) driven by the escape of anodically-evolved oxygen. The electrolyte (30) may circulate upwardly and/or downwardly in the flow-through openings (17) and possibly around the anode structure (12, 13, 15).
    Type: Grant
    Filed: July 2, 2001
    Date of Patent: April 1, 2003
    Assignee: Moltech Invent SA
    Inventor: Vittorio de Nora
  • Patent number: 6533909
    Abstract: A bipolar cell for the electrowinning of aluminium has bipolar electrodes each comprising a carbon cathode body having on one side an active surface on which aluminium is produced and connected on the other side through an oxygen impermeable barrier layer to an electrochemically active anode layer having an oxygen evolving iron oxide-based outer surface. The anode layer may comprise a metal-based anode substrate and a transition metal oxide-based outside layer, in particular an iron oxide-based outside layer, which either is an applied layer or is obtainable by oxidising the surface of the anode substrate which contains iron. During operation, the anode layer can be kept dimensionally stable by maintaining in the electrolyte a concentration of transition metal species which are present as one or more corresponding transition metal oxides in the electrochemically-active layer.
    Type: Grant
    Filed: January 29, 2001
    Date of Patent: March 18, 2003
    Assignee: Moltech Invent S.A.
    Inventors: Jean-Jacques Duruz, Vittorio de Nora
  • Patent number: 6475358
    Abstract: A method of treating a carbonaceous cell component of an electrolyte cell for the production of aluminum, to impart protection against deterioration during operation of the cell. A liquid suspension of a refractory material dispersed in a lignosulfonate binder solution is prepared and applied as a protective coating to the surface of carbonaceous cell components and allowed to dry.
    Type: Grant
    Filed: February 6, 2001
    Date of Patent: November 5, 2002
    Assignee: Alcan International Limited
    Inventors: Amir A. Mirtchi, Jules Bergeron
  • Patent number: 6436272
    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.
    Type: Grant
    Filed: October 4, 2000
    Date of Patent: August 20, 2002
    Assignee: Northwest Aluminum Technologies
    Inventors: Craig W. Brown, Patrick B. Frizzle
  • Patent number: 6423195
    Abstract: An inert anode for the electrolytic production of metals such as aluminum is disclosed. The inert anode includes a ceramic oxide material preferably made from NiO, Fe2O3 and ZnO. The inert anode composition may comprise the following mole fractions of NiO, Fe2O3 and ZnO: 0.2 to 0.99 NiO; 0.0001 to 0.8 Fe2O3; and 0.0001 to 0.3 ZnO. The inert anode may optionally include other oxides and/or at least one metal phase, such as Cu, Ag, Pd, Pt, Au, Rh, Ru, Ir and/or Os. The Ni—Fe—Co—O ceramic material exhibits very low solubility in Hall cell baths used to produce aluminum.
    Type: Grant
    Filed: April 4, 2000
    Date of Patent: July 23, 2002
    Assignee: Alcoa Inc.
    Inventors: Siba P. Ray, Douglas A. Weirauch, Jr., Xinghua Liu
  • Patent number: 6423204
    Abstract: A cermet inert anode for the electrolytic production of metals such as aluminum is disclosed. The inert anode comprises a ceramic phase including an oxide of Ni, Fe and M, where M is at least one metal selected from Zn, Co, Al, Li, Cu, Ti, V, Cr, Zr, Nb, Ta, W, Mo, Hf and rare earths, preferably Zn and/or Co. Preferred ceramic compositions comprise Fe2O3, NiO and ZnO or CoO. The cermet inert anode also comprises a metal phase such as Cu, Ag, Pd, Pt, Au, Rh, Ru, Ir and/or Os. A preferred metal phase comprises Cu and Ag. The cermet inert anodes may be used in electrolytic reduction cells for the production of commercial purity aluminum as well as other metals.
    Type: Grant
    Filed: August 1, 2000
    Date of Patent: July 23, 2002
    Assignee: Alcoa Inc.
    Inventors: Siba P. Ray, Xinghua Liu, Douglas A. Weirauch
  • Patent number: 6419813
    Abstract: Cathode connector means for low temperature aluminum smelting cell for connecting titanium diboride cathode or the like to bus bars.
    Type: Grant
    Filed: November 25, 2000
    Date of Patent: July 16, 2002
    Assignee: Northwest Aluminum Technologies
    Inventors: Craig W. Brown, Theodore R. Beck, Patrick B. Frizzle
  • Patent number: 6419812
    Abstract: A method of producing aluminum in an electrolytic cell containing alumina dissolved in an electrolyte. The method comprises the steps of providing a molten salt electrolyte in an electrolytic cell having an anodic liner for containing the electrolyte, the liner having an anodic bottom and walls including at least one end wall extending upwardly from the anodic bottom, the anodic liner being substantially inert with respect to the molten electrolyte. A plurality of non-consumable anodes is provided and disposed vertically in the electrolyte. A plurality of cathodes is disposed vertically in the electrolyte in alternating relationship with the anodes. The anodes are electrically connected to the anodic liner. An electric current is passed through the anodic liner to the anodes, through the electrolyte to the cathodes, and aluminum is deposited on said cathodes. Oxygen bubbles are generated at the anodes and the anodic liner, the bubbles stirring the electrolyte.
    Type: Grant
    Filed: November 27, 2000
    Date of Patent: July 16, 2002
    Assignee: Northwest Aluminum Technologies
    Inventors: Theodore R. Beck, Craig W. Brown
  • Publication number: 20020027069
    Abstract: A cell for the electrowinning of aluminum comprises at least one non-carbon metal-based anode (10) having an electrically conductive metallic structure (12, 13, 15) which is suspended substantially parallel to a facing cathode (20, 21, 22). Such metallic structure (12, 13, 15) comprises a series of parallel horizontal anode members (15), each having an electrochemically active surface (16) on which during electrolysis oxygen is anodically evolved. The electrochemically active surfaces (16) are in a generally coplanar arrangement to form the active anode surface. The anode members are spaced apart from one another by inter-member gaps forming flow-through openings (17) for the circulation of electrolyte (30) driven by the escape of anodically-evolved oxygen. The electrolyte (30) may circulate upwardly and/or downwardly in the flow-through openings (17) and possibly around the anode structure (12, 13, 15).
    Type: Application
    Filed: July 2, 2001
    Publication date: March 7, 2002
    Inventor: Vittorio de Nora
  • Patent number: 6312570
    Abstract: This invention relates to a new family of materials that exhibits improved stability to the chemical environment used in metal ore reduction, and thus provides an opportunity for improving the energy use and efficiency of such processes by their use. More specifically, the inventions relates to an electrode, used in the construction and/or operation of a reduction cell use to produce metal from ore, which is comprised of a compound or compounds described by the chemical formulas M3NX2 or M2NX, where M is a transition metal, N is a group 3a, 4a or 5a element, and X is carbon or nitrogen; or a composite containing in part, at least one of such compounds.
    Type: Grant
    Filed: February 8, 2000
    Date of Patent: November 6, 2001
    Assignee: Advanced Refractory Technologies, Inc.
    Inventor: Thomas J. Mroz, Jr.
  • Patent number: 6231745
    Abstract: A novel electrolytic reduction cell apparatus and method are disclosed for the production of aluminum, including a copper insert inside the cathode collector bar. In one aspect, a melting allowance slot is provided. In one aspect, the copper insert resides in a slot in the collector bar, the slot having a width dimension of 0.001-0.009 inch (0.0025-0.00229 cm) or 0.1%-0.9% more than the dimension of the copper insert. In one aspect, the copper insert resides in a slot in the collector bar, the slot having a length dimension of 0.25-0.97 inch (0.635-2.5 cm) or 0.37-1.44% more than the dimension of the copper insert. In one aspect, the copper insert is located from a point proximate about 2 inches (5 cm) from the cell center to a point proximate about 69.35 inches (176 cm) from the cell center towards the first cell wall. In one aspect, the copper insert cross-section is about 0.042 to about 0.125 times the cross-sectional area of the cathode collector bar.
    Type: Grant
    Filed: October 13, 1999
    Date of Patent: May 15, 2001
    Assignee: Alcoa Inc.
    Inventors: Graham E. Homley, Donald P. Ziegler
  • Patent number: 6217739
    Abstract: A method of producing commercial purity aluminum in an electrolytic reduction cell comprising inert anodes is disclosed. The method produces aluminum having acceptable levels of Fe, Cu and Ni impurities. The inert anodes used in the process preferably comprise a cermet material comprising ceramic oxide phase portions and metal phase portions.
    Type: Grant
    Filed: November 1, 1999
    Date of Patent: April 17, 2001
    Assignee: Alcoa Inc.
    Inventors: Siba P. Ray, Xinghua Liu, Douglas A. Weirauch, Jr.
  • Patent number: 6162334
    Abstract: An inert anode for production of metals such as aluminum is disclosed. The inert anode comprises a base metal selected from Cu and Ag, and at least one noble metal selected from Ag, Pd, Pt, Au, Rh, Ru, Ir and Os. The inert anode may optionally be formed of sintered particles having interior portions containing more base metal than noble metal and exterior portions containing more noble metal than base metal. In a preferred embodiment, the base metal comprises Cu, and the noble metal comprises Ag, Pd or a combination thereof.
    Type: Grant
    Filed: October 27, 1999
    Date of Patent: December 19, 2000
    Assignee: Alcoa Inc.
    Inventors: Siba P. Ray, Xinghua Liu
  • Patent number: 6083362
    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.
    Type: Grant
    Filed: August 6, 1998
    Date of Patent: July 4, 2000
    Assignee: University of Chicago
    Inventors: John N. Hryn, Michael J. Pellin, Alan M. Wolsky, Wallis F. Calaway, Jr.
  • Patent number: 5814800
    Abstract: A card reader (for example, a swipe card reader for reading bank or security cards) is disclosed which comprises a detector for detecting surface features of the card such as embossed characters. In this way, a security check for false cards is implemented.
    Type: Grant
    Filed: June 30, 1995
    Date of Patent: September 29, 1998
    Assignee: Meggitt Ltd.
    Inventors: Peter Marsh, Iain Andrew James Lamont