EP0931182A1 - Anodes ultrastables pour cellules de production d'aluminium - Google Patents

Anodes ultrastables pour cellules de production d'aluminium

Info

Publication number
EP0931182A1
EP0931182A1 EP97942654A EP97942654A EP0931182A1 EP 0931182 A1 EP0931182 A1 EP 0931182A1 EP 97942654 A EP97942654 A EP 97942654A EP 97942654 A EP97942654 A EP 97942654A EP 0931182 A1 EP0931182 A1 EP 0931182A1
Authority
EP
European Patent Office
Prior art keywords
aluminum
nickel
additive element
iron
elements
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP97942654A
Other languages
German (de)
English (en)
Other versions
EP0931182B1 (fr
Inventor
Jainagesh A. Sekhar
Vittorio De Nora
James Jenq Liu
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Moltech Invent SA
Original Assignee
Moltech Invent SA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Moltech Invent SA filed Critical Moltech Invent SA
Publication of EP0931182A1 publication Critical patent/EP0931182A1/fr
Application granted granted Critical
Publication of EP0931182B1 publication Critical patent/EP0931182B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/23—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces involving a self-propagating high-temperature synthesis or reaction sintering step
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C1/00—Making non-ferrous alloys
    • C22C1/04—Making non-ferrous alloys by powder metallurgy
    • C22C1/047—Making non-ferrous alloys by powder metallurgy comprising intermetallic compounds
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
    • C25C3/00—Electrolytic production, recovery or refining of metals by electrolysis of melts
    • C25C3/06—Electrolytic production, recovery or refining of metals by electrolysis of melts of aluminium
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
    • C25C3/00—Electrolytic production, recovery or refining of metals by electrolysis of melts
    • C25C3/06—Electrolytic production, recovery or refining of metals by electrolysis of melts of aluminium
    • C25C3/08—Cell construction, e.g. bottoms, walls, cathodes
    • C25C3/12—Anodes
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
    • C25C7/00—Constructional parts, or assemblies thereof, of cells; Servicing or operating of cells
    • C25C7/02—Electrodes; Connections thereof

Definitions

  • This invention relates to cell components, particularly anodes, for use in the
  • cryolite in particular cryolite.
  • the invention is more particularly concerned with the production of cell
  • reaction product when ignited undergoes a micropyretic reaction to produce a reaction product.
  • cerium oxy fluoride coated with a protective coating of cerium oxy fluoride, formed in-situ in the cell or pre-
  • cerium oxyfluoride based coating comprising mixed oxides of cerium and one or more of
  • SHS temperature synthesis
  • particulate or fibrous reactants included aluminum usually with titanium and boron; the binders included copper and aluminum; the fillers included various oxides, nitrides, borides,
  • the described composites included copper/aluminum oxide-titanium
  • the binder could be a metal mixture including aluminum, nickel and up to 5
  • the anodes could be formed by oxidizing a metal alloy substrate of suitable composition.
  • This teaching provided an anode for aluminum production where the problem of
  • the metal electrode being covered with an oxide layer which remained stable during electrolysis and protected the substrate from corrosion by the electrolyte.
  • molten fluoride electrolyte comprises a porous micropyretic reaction product derived from
  • doping elements such as chromium, manganese, titanium, molybdenum, cobalt, zirconium, niobium, cerium, oxygen, boron and nitrogen included in a quantity of up to 5 wt% in total.
  • the porous micropyretic reaction product contained metallic and/or intermetallic phases, and a composite oxide surface formed in-situ from the metallic and intermetallic phases contained in the porous micropyretic reaction product, by anodically polarizing the
  • micropyretic reaction product in a molten fluoride electrolyte containing dissolved alumina.
  • the in-situ formed composite oxide surface comprised an iron-rich relatively dense outer portion, and an aluminate-rich relatively porous inner portion.
  • Comparative anodes of similar compositions i.e. similar to those of the anodes of
  • Patent 5,510,008 and WO96/ 12833 is unexpectably improved by certain additive elements.
  • the invention relates to a cell component, preferably an anode, for the electrowinning of aluminum by the electrolysis of alumina dissolved in a molten fluoride electrolyte, comprising a porous micropyretic reaction product of particulate nickel, aluminum, iron and optionally, copper, and of at least one additive element in an effective
  • the porous micropyretic reaction product containing metallic and intermetallic phases which preferably form a composite oxide
  • surface layer more preferably comprising an iron-rich relatively dense outer portion and an aluminate-rich relatively porous inner portion, wherein said layer is formed when the
  • porous micropyretic reaction product is anodically polarized in a molten fluoride electrolyte
  • the product After electrolysis or oxidation, the product comprises a porous core and the composite oxide surface. Thus, the product can be characterized as a "graded" material.
  • composition of the micropyretic reaction product is important to the formation of a dense composite oxide surface preferably comprising an iron-rich relatively dense outer portion which is associated with an aluminate-rich relatively porous inner portion by diffusion of the metals/oxides during the in-situ production of the oxide surface.
  • micropyretic reaction product is preferably produced from the particulate
  • nickel, aluminum, iron, copper and the additive element in the amounts 50-90 wt% nickel, 3-20 wt% aluminum, 5-20 wt% iron, 0-15 wt% copper and 0.5-5 wt% of said at least one additive element from the group consisting of silicon, tin, zinc, vanadium, indium,
  • the micropyretic reaction product is produced from 60-80 wt% nickel, 3-10 wt% aluminum, 5-20 wt iron and 5-15 wt% copper, plus 0.5-5 wt% of the selected additive element(s).
  • combustion temperature T c are important processing parameters. See, for example, Processing of Composite Materials by the Micropyretic Synthesis Method, M. Fu and J.A. Sekhar, Key Eng. Mat., Trans. Tech Publications, vol. 108-110, pp. 19-44 (1995)). It has
  • combustion temperature decreased with the presence of iron, copper and zinc, which do not contribute to the energy developed during the reaction. Contrarily the combustion temperature increased with the presence of nickel, aluminum, silicon or tin, because these elements
  • Preferred embodiments of the invention include silicon, tin or zinc as additive element in an amount of 0.5 to 3 wt% of the total.
  • Preferred elements from the lanthanide series are praesodymium, neodymium and
  • ytterbium as well as misch metal which is a mixture of cerium, lanthanum, neodymium and other rare-earth metals. These elements are also preferably included as additive element in an amount of 0.5 to 3 wt% of the total.
  • micropyretic reactions product was tested in the absence of the additive elements for effect of the aluminum content.
  • the resulting composites have good adherence with cerium oxyfluoride coatings
  • micropyretic reaction products were also tested in the absence of the additive
  • micropyretic reaction products were further tested in the absence of the additive elements for effect of copper content. Below 5 wt% copper down to 0 wt% copper results in anodes with higher corrosion rate but which are nevertheless acceptable, and more than
  • the particulate nickel may advantageously have a larger particle size than the
  • particulate aluminum, iron and copper particulate aluminum, iron and copper.
  • Large particle size nickel for example up to about 150 micrometers, is preferred.
  • Fine nickel particles, smaller than 10 micrometers, tend to lead to very fine NiAl, Ni 3 Al or NiOx particles which may increase corrosion when the
  • NiAlO, NiAlFeO or FeAlO phases on the surface, which inhibits corrosion and also promotes a porous structure.
  • nickel particles in the range 10 to 20 micrometers, these small nickel
  • Aluminum particles in the size range 5 to 20 micrometers. Very large aluminum particles (100 mesh) tend to react incompletely. Very fine aluminum particles, below 5 micrometers, tend to have a strong oxidation before the micropyretic
  • the powder mixture may be compacted preferably by uniaxial pressing usually at about 200-250 Mpa, or cold isostatic pressing (OP), and the micropyretic reaction may be
  • micropyretic synthesis is preferred, at about 1000°C. Excellent results have been obtained with combustion in air.
  • the powder mixture is preferably compacted dry, such as by ball milling. Alternatively, liquid binders may be used for compaction.
  • the micropyretic reaction also called self propagating high temperature synthesis or combustion synthesis, can be initiated by applying local heat to one or more points of
  • reaction body by a convenient heat source such as an electric arc, electric spark, flame,
  • reaction which propagates through the reaction body along a reaction front which may be self propagating or assisted by a heat source, as in a furnace. Reaction may also be initiated by heating the entire body to initiate
  • reaction atmosphere is not
  • the micropyretic reaction product has a porous structure comprising at least two metallic and/or intermetallic phases.
  • the micropyretic reaction product comprises at least one intermetallic compound from the group consisting of nickel-iron, nickel-aluminum, nickel-copper, aluminum-iron, nickel-aluminum-copper and nickel- aluminum-iron-copper containing intermetallic compounds.
  • the porosity and microstructure of the micropyretic reaction product are important for the in-situ formation of the preferred surface oxide layer since the pores accommodate for thermal expansion, leaving the outer oxide layer intact during electrolysis.
  • the porous micropyretic reaction product may comprise nickel
  • aluminide Ni 3 Al
  • copper in solid solution with copper, and possibly also in solid solution with other metals and oxides, including silicon, tin, zinc and compounds thereof (including oxides), or of the other additive elements, and mixtures.
  • other metals and oxides including silicon, tin, zinc and compounds thereof (including oxides), or of the other additive elements, and mixtures.
  • preferred cell component/anode material comprises a major amount of Ni and Ni 3 Al and
  • NiCu and NiFe in the substrate and a major amount of NiO and a minor amount of NiFe 2 O 4 , ZnO and NiZnFe 2 O 4 (nickel zinc ferrite) in the mixed oxide surface
  • the surface of such materials contains non-stoichiometric conductive oxides wherein lattice vacancies are occupied by the metals, providing an outstanding conductivity while retaining the property of ceramic oxides to resist oxidation.
  • the aluminum is depleted from the core of the cell
  • Ni 3 Al being replaced by Ni 3 Fe.
  • the aluminum migrates to the surface.
  • Most of the copper is also present in the core as is the iron, because both copper and iron are highly soluble in nickel. It has been observed that Ni 3 Al
  • Ni 3 Fe are both considerably superior to NiAl and NiFe, respectively, in terms of corrosion resistance and oxidation resistance. Both pre- and post-electrolysis, the preferred cell components of the present invention have a predominance of Ni 3 Al and Ni 3 Fe versus
  • the micropyretic reaction product can also be produced from a mixture containing, in addition to said at least one additive element from the group consisting of silicon, tin, zinc, vanadium, indium, hafnium, tungsten, elements from the lanthanide series starting
  • praesodymium from praesodymium, and misch metal (preferably in an amount of 05. to 3 wt% of the
  • an optional additional additive element from the group consisting of chromium, manganese, titanium, molybdenum, cobalt, zirconium, niobium, tantalum, yttrium, cerium, lanthanum, oxygen, boron and nitrogen.
  • the total of the main and the additional additive elements preferably should not exceed 7 wt% of the total.
  • the composite oxide surface usually comprises an iron-rich relatively dense outer portion, and an aluminate-rich relatively porous inner portion which integrate into the porous structure of the substrate. Analysis of some of the specimens has shown that there is present between the iron-rich outer portion and the aluminate-rich inner portion, an
  • the outermost iron-rich oxide layer when present, is a homogenous, dense layer
  • iron usually mainly nickel ferrite and nickel-zinc ferrite (NiZnFe 2 O 4 ) doped with aluminum (when zinc is the additive element).
  • Nickel-zinc ferrite has been observed to have excellent properties as an anode
  • the composite oxide surface comprises nickel oxide, nickel ferrite, zinc oxide and nickel-zinc ferrite.
  • the aluminum-depleted intermediate oxide layer when present, usually comprises
  • nickel and iron oxides of nickel and iron, with nickel highly predominant, for example iron-doped nickel oxide which provides good electrical conductivity of the anode and contributes to good resistance during electrolysis.
  • the innermost aluminate-rich oxide part which is usually present, is slightly more
  • This aluminate-rich part may be a homogenous phase of aluminum oxide with iron and nickel in solid solution, and usually
  • the porous metal substrate close to the oxide layer, often comprises nickel in
  • the substrate is usually largely depleted in aluminum as the aluminum is used to create the
  • the substrate is also depleted in iron.
  • metallic and intermetallic core deeper inside the substrate is also preferably depleted of aluminum as a result of internal oxidation in the open pores of the material and diffusion of the oxidized aluminum to the surface.
  • the metallic and intermetallic core (deep down in the sample), can have a similar composition to the metallic core nearer the oxide surface.
  • Interconnecting pores in the metal substrate may be filled with cryolite by penetration during formation of the oxide layer, but the penetrated material becomes sealed off from the electrolyte by the dense oxide coating and does not lead to corrosion inside the
  • the invention also provides a method of manufacturing a cell component, preferably an anode, for the production of aluminum by the electrolysis of alumina in a
  • molten fluoride electrolyte comprising reacting a micropyretic reaction mixture of
  • particulate nickel, aluminum, iron and optionally copper and at least one additive element selected from the group consisting of silicon, tin, zinc, vanadium, indium, hafnium, tungsten, elements from the lanthanide series starting from praesodymium, and misch metal in an amount up to 8 wt% of the total reactants, to produce a porous micropyretic reaction product containing metallic and intermetallic phases, and preferably anodically polarizing the micropyretic reaction product in a molten fluoride electrolyte containing dissolved
  • alumina or subjecting it to contact with oxidizing gas at high temperatures, to produce, from the metallic and intermetallic phases contained in the porous micropyretic reaction product, an in-situ or ex-situ formed composite oxide surface usually comprising an iron- rich relatively dense outer portion and an aluminate-rich relatively porous inner portion.
  • Another aspect of the invention is a method of electrowinning aluminum by the electrolysis of alumina in a molten fluoride electrolyte.
  • the electrowinning method is a method of electrowinning aluminum by the electrolysis of alumina in a molten fluoride electrolyte.
  • a starter anode which is a porous micropyretic reaction product
  • fluoride electrolyte containing dissolved alumina or subjecting it to contact with oxidizing gas at high temperatures, to produce a composite oxide surface usually comprising an iron- rich relatively dense outer portion and an aluminate-rich relatively porous inner portion.
  • Electrolysis is then continued, using the same electrolyte (in which the in-situ oxide layer was formed) or a different molten fluoride electrolyte containing dissolved alumina, to produce aluminum using the in-situ oxidized starter anode.
  • the composite in which the in-situ oxide layer was formed
  • a different molten fluoride electrolyte containing dissolved alumina to produce aluminum using the in-situ oxidized starter anode.
  • the composite in which the in-situ oxide layer was formed
  • cerium would be added to deposit a cerium oxyfluoride based protective coating upon the composite oxide layer.
  • the preferred final stage of production formation of the composite oxide layer on the anode surface
  • Yet another aspect of the present invention is a precursor of a cell component of an aluminum production cell which is ignitable to produce by micropyretic reaction, a cell
  • component made of a composite material said precursor comprising particulate nickel
  • additive element selected from the group consisting of silicon, tin, zinc, vanadium, indium, hafnium, tungsten, elements from the lanthanide series starting from praesodymium, and misch metal, said additive element
  • a coating may be applied to the preferred in-situ formed oxide layer; a preferred coating being in-situ formed cerium oxyfluoride according to US Patent No. 4,614,569
  • the cerium oxyfluoride may optionally contain additives such as compounds of tantalum, niobium, yttrium, praesodymium and other rare earth elements; this coating being maintained by the addition of cerium and possibly other elements to the molten
  • cryolite-based electrolyte Production of such a protective coating in-situ leads to dense
  • Figure 1 shows X-ray diffraction spectra, at the Two-Theta position, of two metallic/intermetallic micropyretic reaction substrates, one without and the other with zinc
  • Figure 2 shows corresponding X-ray diffraction spectra of the metallic/intermetallic
  • micropyretic oxide layers formed on the substrates of Figure 1.
  • a powder mixture was prepared from 73 wt% (68 atomic %) nickel, 100 mesh ( ⁇ 149 micrometer), 6 wt% (12 atomic %) aluminum, 325 mesh ( ⁇ 42 micrometer), 11
  • the dry mixture i.e. without any liquid fiber
  • the pressed samples were then ignited in a furnace at 900°C or 1050°C to initiate a
  • the cell voltage was from 2.9 to 2.5 Volts, and during the second period
  • the cell voltage was from 3.3 to 4.4 Volts.
  • the anode specimens were removed. The specimens showed no signs of dimensional change, and the metallic
  • the outermost oxide layer was a homogeneous, dense, oxide-only layer devoid of
  • This oxide layer comprised oxides of nickel, aluminum and iron with predominant quantities of iron.
  • the quantities of metals present in atomic % were 32% nickel, 21 % aluminum, 45% iron and 2% copper. It is believed that this phase comprises
  • the intermediate oxide layer was composed of large grains which interpenetrated
  • oxide layer comprised oxides of nickel and iron, with nickel highly predominant.
  • the quantities of metals present in atomic % were 83% nickel, 3% aluminum, 13% iron and 1 % copper. It is believed that this phase is iron-doped nickel oxide which would explain
  • the oxide layer below the intermediate layer was slightly more porous that the top
  • the porous metal substrate in contact with the oxide layer is comprised of nickel with small quantities of copper, iron and aluminum. It is largely depleted in aluminum, as
  • the aluminum is used to create the aluminate layer on top of it.
  • the composition of the porous substrate in atomic % was 77.8% nickel, 5.3% aluminum, 3.5% iron and 13.5% copper.
  • the metallic core deeper inside the substrate is also depleted of aluminum as a
  • the composition in atomic % was 77.2% nickel, 1.8% aluminum, 9.7% iron and 11.3% copper. All interconnecting pores in the metal substrate were filled with cryolite, and in some cryolite-filled pores, a second phase identified as aluminum fluoride is seen, probably
  • Example 2 The procedure of Example 1 was repeated varying the proportions in the starting mixture and with zirconium, chromium, titanium, yttrium or niobium as an extra component in a total amount up to 5 wt% of the total reactants.
  • the particle size of the chromium was 325 mesh ( ⁇ 425 micrometer).
  • the composition was nickel 73 wt% ,
  • Example 3 aluminum 6 wt%, iron 6 wt% , copper 10 wt% and chromium or other additive up to 5 wt%. Results comparable to those for the samples of Example 1 were obtained.
  • Example 3
  • silicon, tin or zinc as additives in an amount up to 5 % of the total reaction
  • Examples 1 and 2 i.e. according to U.S. Patent 5,510,008 and WO96/12833 (Sekhar et al), have shown outstanding properties as dimensionally stable anodes or anode substrates
  • the oxide surface layer was much thinner, i.e. it grew at a much slower rate than that for comparative examples 1 and 2.
  • the added metals in particular
  • Figures 1 and 2 show the Two-Theta X-ray diffraction spectra of two samples, one with a composition Ni(73)Al(6)Cu(10)Fe(l l) wt%, the other with a composition
  • Theta is half the angle between the diffracted X-ray beam and the original X-ray beam direction.
  • a moving X-ray detector records the 2 Theta
  • the primary phases of the metallic/intermetallic substrate are Ni and Ni 3 Al, which
  • Cu and Fe have high solubility in Ni and Ni 3 Al, and exist in solid solution in
  • the mixed oxide layer is the part of the anode which contacted the cryolite alumina
  • this layer is primarily made up of NiO and NiFe 2 O 4 , which have low solubility in cryolite.
  • Zn has a high solubility in the Ni and the Ni 3 Al and exists in solid solution or as zinc compounds in small amounts that are not detected by the X-ray diffraction.
  • the oxides include NiO, NiFe 2 O 4) NiZnFe 2 O 4 and ZnO. It is believed that the complex oxides density the mixed oxide layer and enhance the oxidation resistance, especially

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Electrochemistry (AREA)
  • Mechanical Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Electrolytic Production Of Metals (AREA)

Abstract

Une anode, destinée à l'extraction électrolytique d'aluminium par électrolyse d'alumine dissoute dans un électrolyte fondu à base de fluorure, comprend un produit réactionnel micropyrétique poreux à base de nickel, d'aluminium, de fer, de cuivre et au moins un additif choisi entre le silicium, l'étain, le zinc, le vanadium, l'indium, le hafnium, le tungstène, les éléments de la série des lanthanides à partir du praesodyme, et un mischmetal. Le produit réactionnel micropyrétique contient des phases métalliques et intermétalliques, avec une surface oxydée composite produite in situ par polarisation anodique dudit produit réactionnel dans un électrolyte fondu à base de fluorure contenant de l'alumine dissoute, ou par traitement à haute température dans un gaz oxydant. La surface oxydée composite comprend généralement une partie externe riche en fer, relativement dense, et une partie interne riche en aluminates, relativement poreuse.
EP97942654A 1996-09-23 1997-09-23 Anodes ultrastables pour cellules de production d'aluminium Expired - Lifetime EP0931182B1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US9615176 1996-09-23
WOPCT/US96/15176 1996-09-23
PCT/US1997/016865 WO1998012363A1 (fr) 1996-09-23 1997-09-23 Anodes ultrastables pour cellules de production d'aluminium

Publications (2)

Publication Number Publication Date
EP0931182A1 true EP0931182A1 (fr) 1999-07-28
EP0931182B1 EP0931182B1 (fr) 2001-12-05

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EP97942654A Expired - Lifetime EP0931182B1 (fr) 1996-09-23 1997-09-23 Anodes ultrastables pour cellules de production d'aluminium

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EP (1) EP0931182B1 (fr)
CA (1) CA2269727A1 (fr)
DE (1) DE69708903T2 (fr)
WO (1) WO1998012363A1 (fr)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6423195B1 (en) * 1997-06-26 2002-07-23 Alcoa Inc. Inert anode containing oxides of nickel, iron and zinc useful for the electrolytic production of metals
WO2001043208A2 (fr) * 1999-12-09 2001-06-14 Duruz, Jean-Jacques CELLULES D'ELECTROEXTRACTION D'ALUMINIUM FAISANT APPEL A DES ANODES A METAL
NZ534805A (en) * 2002-03-15 2006-03-31 Moltech Invent S Surface oxidised nickel-iron metal anodes for aluminium production
AU2013275996B2 (en) * 2012-06-11 2016-10-27 Inner Mongolia United Industrial Co., Ltd. Inert alloy anode used for aluminum electrolysis and preparation method therefor
FR3022917B1 (fr) * 2014-06-26 2016-06-24 Rio Tinto Alcan Int Ltd Materiau d'electrode et son utilisation pour la fabrication d'anode inerte
CN115849419B (zh) * 2022-11-22 2024-03-29 贵州大学 一种载氟氧化铝的生产方法及生产的载氟氧化铝的应用

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU685053B2 (en) * 1993-04-19 1998-01-15 Moltech Invent S.A. Micropyretically-produced components of aluminium production cells
US5510008A (en) * 1994-10-21 1996-04-23 Sekhar; Jainagesh A. Stable anodes for aluminium production cells

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO9812363A1 *

Also Published As

Publication number Publication date
EP0931182B1 (fr) 2001-12-05
DE69708903T2 (de) 2002-06-27
CA2269727A1 (fr) 1998-03-26
DE69708903D1 (de) 2002-01-17
WO1998012363A1 (fr) 1998-03-26

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