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EP2688130B1 - Ensemble a anode inerte - Google Patents

Ensemble a anode inerte Download PDF

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Publication number
EP2688130B1
EP2688130B1 EP13183888.0A EP13183888A EP2688130B1 EP 2688130 B1 EP2688130 B1 EP 2688130B1 EP 13183888 A EP13183888 A EP 13183888A EP 2688130 B1 EP2688130 B1 EP 2688130B1
Authority
EP
European Patent Office
Prior art keywords
solid material
electrolysis apparatus
alumina
bath
anodes
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.)
Expired - Lifetime
Application number
EP13183888.0A
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German (de)
English (en)
Other versions
EP2688130A1 (fr
Inventor
Leroy E. D'astolfo
Calvin Bates
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.)
Alcoa Corp
Original Assignee
Alcoa Corp
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Filing date
Publication date
Application filed by Alcoa Corp filed Critical Alcoa Corp
Priority to SI200332555T priority Critical patent/SI2688130T1/en
Priority claimed from EP03786931.0A external-priority patent/EP1588443B1/fr
Publication of EP2688130A1 publication Critical patent/EP2688130A1/fr
Application granted granted Critical
Publication of EP2688130B1 publication Critical patent/EP2688130B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • 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

Definitions

  • the present invention relates to structures and methods for protecting inert anodes and other electrodes and electrode support materials from degradation by a cryolite-based molten electrolyte bath, and from HF/O 2 and other gases generated in an electrolytic cell.
  • the present invention also improves metal production, such as aluminum production, by limiting bath and metal contamination and reducing thermal shock during initial preheating and placement of anodes in electrolytic cells.
  • a Hall-Heroult reduction cell typically comprises a steel shell having an insulating lining of refractory material, which in turn has a lining of carbon that contacts the molten constituents.
  • the electrolyte is based on molten cryolite (Na 3 AlF 6 ) which may contain a variety of additives such as LiF, CaF 2 , MgF 2 or AlF 3 , and contains dissolved high purity alumina (Al 2 O 3 ).
  • the carbon lining has a useful life of three to eight years, or even less under adverse conditions.
  • the deterioration of the cathode bottom is due to erosion and penetration of electrolyte and liquid aluminum as well as intercalation of sodium, which causes swelling and deformation of the cathode carbon blocks.
  • the penetration of sodium species, other substances contained in cryolite, or air leads to the formation of toxic compounds including cyanides.
  • Anodes are at least partially submerged in the bath and are subject to the same conditions.
  • the Hall process although commercial today, has certain limitations, such as the requirement that the process operate at relatively high temperatures, typically around 970°C to 1000°C.
  • the high cell temperatures are necessary to achieve a high alumina solubility.
  • the electrolyte and molten aluminum progressively react with most carbon or ceramic materials, creating problems of electrode erosion, which can cause cell contamination and metal and electrolyte containment.
  • the electrolyte constituents are adverse to the rest of the cell.
  • Electrolytic reduction cells must be heated from room temperature to approximately the desired 1000°C operating temperature before the productions of metal can be initiated. Heating should be done gradually and evenly to avoid thermal shock to the cell components which can in turn cause breakage or spalling. The heating operation minimizes thermal shock to the lining, the electrodes and other attached structural assemblies upon introduction of the electrolyte and molten metal to the cell.
  • Prior art carbon anodes can be placed into the electrolyte at ambient temperature, and heated by the energy of the cell to operating temperatures, at which time the nominal current of the anode will be attained.
  • thermal shock/cracking can occur both during movement of the anodes into position and during their placement into the molten salt.
  • Thermal shock relates to the thermal gradient (positive or negative) through the anode that occurs during the movement from the preheat furnace to the cell, and also upon insertion of the anodes into the molten salt.
  • a thermal gradient as low as 50°C can cause cracking.
  • the heat insulating layer was made of expanded, fibrous kaolin-china clay (Al 2 O 3 •2SiO 2 •2H 2 O), which would subsequently dissolve in the molten electrolyte, introducing Si.
  • a refractory repair mass is taught in U.S. Patent Specification No. 5,928,717 (Cherico et al. ).
  • a powder mixture of alumina, metallic combustible such as magnesium, zirconium, chromium and aluminum plus additive selected from aluminum fluoride, barium sulfate, cerium oxide or calcium fluoride are used with an oxygen stream, under pressure, to contact and cure non-uniform crystalline structures and the like at the surface of used refractory. This however, primarily relates to repair and to already present refractories which have been contacted with molten aluminum or molten glass.
  • an array or assembly of uncovered inert anodes can be mounted on a cast refractory insulating lid below a metal plate, through which a continuous electrical path from the cell is provided.
  • a cast refractory insulating lid below a metal plate, through which a continuous electrical path from the cell is provided.
  • Aluminum electrolysis cells have historically employed carbon anodes on a commercial scale.
  • the energy consumption and cost of aluminum smelting can be significantly reduced with the use of inert, non-consumable, and dimensionally stable anodes.
  • Use of inert anodes rather than traditional carbon anodes allows a highly productive cell design to be utilized, thereby reducing capital costs.
  • Significant environmental benefits are also realized because inert anodes produce essentially no CO 2 or CF 4 emissions.
  • Inert anodes can be made of, for example a ceramic, metal ceramic "cermet" or metal containing material.
  • ceramic inert anode compositions are provided in U.S. Patent Specification Nos. 6,126,799 ; 6,217,739 B1 ; 6,372,119 B1 ; and 6,423,195 B1 (all Ray et al. respectively), herein incorporated by reference.
  • These anodes comprise a ceramic phase and may also comprise a metal phase. They are essentially void free and while they exhibit low solubility and good dimensional stability there is still some corrosion in Hall cell baths at 1000°C.
  • an electrolysis apparatus comprising a plurality of anodes, each anode having a lower portion immersed in molten electrolyte bath, wherein a solid material selected from the group consisting of alumina and cryolite, and mixtures thereof, together with a minor effective amount, about 5 wt.% to 25 wt.% of cementitious binder, said solid material contacting and circumscribing at least an upper portion of at least one of said anodes.
  • the solid material can be applied by molding/casting, dipping, spraying or the like, and can be made that upon dissolution on or very little impurities are introduced into the molten bath.
  • the invention also provides an electrolysis apparatus comprising an inert anode system comprising at least one inert anode having a lower portion in contact with a molten salt bath, where at least an upper portion of the inert anode contacts and is circumscribed by a solid material subject to attack by gases from the bath, wherein the solid material is selected from the group consisting of alumina-cement and cryolite-alumina, both of which will dissolve in the presence of the molten salt bath.
  • the alumina-cement material is preferably at least 92% pure Al 2 O 3 , insulating and very advantageously, highly temperature resistant.
  • the alumina-cryolite material is preferably about 40 wt.% to 80 wt.% cryolite, at least 2 wt.% alumina and 5 wt.% to 25 wt.% of a high temperature resistant cementitious material.
  • cryolite is meant, sodium aluminum fluoride which may contain various alkali and alkaline earth elements, such as calcium, magnesium, potassium, lithium, and beryllium in various ratios as well as the specific formula Na 3 AlF 6 .
  • Alumina can also be used, as a major component with from 5 wt.% to 15 wt.% heat resistant refractory cementitious material.
  • the alumina-cement structure can, advantageously be formulated to be 50 vol.% to 95 vol.% dense (that is having 5 vol.% to 50 vol.% porosity) allowing air inclusions providing advantages of over 1000°C preheating before insertion into the bath.
  • the alumina can also contain up to 15 wt.% other oxides, such as, for example, CaO 2 , SiO 2 and others as well as the cement previously mentioned.
  • an electrolytic cell comprising an inert anode system 10 is shown in an electrolysis apparatus, used for example to produce aluminum, and comprises a top structure and a plurality of inert anodes 14 and 14'.
  • the top structure can include a refractory 12 to which the inert anodes are attached through a plate 18.
  • the refractory material can be a flat structure, or, for example, the hollow box type structure shown, filled with insulation 28.
  • Metal bolts 16 can anchor the inert anodes to the refractory 12 and to a top metal, usually steel plate 18 anchored to the refractory 12 by metal anchors 20 or the like.
  • the entire inert anode system, 12, 18 and 28, is attached to a massive metal holder 22.
  • the inert anode system can be quite large, with the length 30 of the refractory being from about 1 to 2 m (3 feet to 6 feet), and the wall thickness 31 being from about 2 cm to 10 cm.
  • the refractory 12 has an outer or exterior side 24 as shown, and can have an interior side 26.
  • the interior of the refractory 12 can be filled with layers of low density ceramic boards 28 as shown, or insulating mat made from ceramic fibers, or other materials, or left hollow. As can be seen, this type of system is quite complicated in construction.
  • Gases 32 from the molten salt bath 34 and anode 14, 14' are very aggressive even to stainless steel, especially several gases in combination.
  • the gases shown as circles (bubbles) 32 from either the bath or the anodes 14' pass above the bath 34 as the gas flow arrows 36.
  • the molten salt bath 34 usually used in the Hall process to produce aluminum is based on molten cryolite (as NaF plus AlF 3 ), at a bath weight ratio of NaF to AlF 3 in a range of about 1.0:1 to 1.6:1 and at a temperature usually from about 850°C to 1050°C, preferably from 950°C to 975°C.
  • bath additives can be added for various purposes.
  • the inert anodes are not totally immersed in the molten bath, usually the top edge of the anode is above the bath a distance 38, usually about 5 cm to 30 cm, called the gas or vapor space.
  • the gases 32 most commonly generated include HF, AlF 3 , O 2 , and NaAlF 4 .
  • a combination of HF and O 2 is particularly corrosive to metals and ceramics especially at temperatures over about 400°C.
  • Oxygen is generated at the anodes according to the reaction: 2Al 2 O 3 (soln) + 12e - ⁇ 4Al (liquid) +3O 2 (gas) (I) and HF is generated from the bath according to the reaction (II): 2AlF 3 (soln) + 3H 2 O ⁇ Al 2 O 3 (soln) + 6 HF (gas) (II).
  • the source of water is the chemically bound water intrinsic to the smelting grade alumina fed to the smelting cell.
  • the temperature of the refractory 12 at points 13 where there might be HF and O 2 contact is about 700°C to 1000°C depending on the distance from the molten cryolite.
  • FIG. 2 one embodiment of the simpler and preferred inert anode system 10 of this invention is shown as assembled and, in the instance shown, cast, before contact with the molten electrolyte.
  • the system 10 also contains a plurality of inert anodes 14 and 14', and a circumscribing support material 12'.
  • An attached metal plate 18 is secured by a number of anchors 20 all held by massive metal holder 22.
  • a dramatically different anode circumscribing solid structure 12' heretofore not considered, is used, which contacts the anodes 14 and 14' at points 40 and 42 when the solid structure 12' is first cast, before insertion into an electrolysis apparatus.
  • Comparison with Fig. 1 shows the simplicity of this new system.
  • Fig. 3 shows, basically, the same design and circumscribing result, as Fig. 2 , but application of the solid structure 12 by a dipping or spraying means where the solid structure 12' will still completely fill in between the inert anodes such as 14 and 14'. While not as uniform an outside structure, the application is cost effective, serves the same purpose as a neat, uniform casting/molding operation shown in Fig. 2 , is lighter and uses less material.
  • Fig. 4 shows the system 10 of Figs. 2 or 3 inserted into an electrolysis apparatus, such as could be used to produce aluminum, where molten cryolite 34 (comprising Na 3 AlF 6 ) contacts the inert anodes 14 and 14' and has dissolved a portion of the reduced solid material 12' a distance 44 from the bottom of anodes 14 and 14' leaving a remaining solid material thickness 46.
  • the remaining thickness 46 can be from 30% to 80% preferably from 40% to 70% of the original solid structure thickness 48, shown in Figs. 2 and 3 .
  • a remaining solid structure thickness of 50% although for the dipped or sprayed coating the surface would be a little rougher than shown and from 3 to possibly 5 or more repetitions may be required to get the desired block type shape.
  • a remaining solid structure thickness of less than 30% will weaken the entire inert anode system 10 and impair the insulating effect of the solid material 12'.
  • a remaining solid structure thickness greater than about 80% will not provide sufficient anode surface to allow the cell to function properly.
  • cryolite 34 from the bath Over a certain vapor space 38, cryolite 34 from the bath will condense and solidify on the bottom of the solid structure 12', in a steady state operation, adding additional solid structure as shown by the dotted lines.
  • the entire refractory slab, insulating boards, protective outer inert anode coatings/coverings, all of which dissolved to a certain extent into the molten bath causing impurities, are replaced with a block of either alumina, preferably 95 wt.% to 99 wt.% pure, or bath ⁇ alumina material, both of which contain a binder cement, to provide the solid structure 12' shown in Figs. 2 and 3 . If the surrounding alumina or bath + alumina support 12' dissolves into the molten cryolite bath 34 no harm is done and, no more than 0.5 wt.% impurities based on molten bath weight, or preferably no impurities are added to the molten bath.
  • This also simplifies the structure of the entire system 10 dramatically, with substantial time and cost savings. It also makes anode alignment much less critical in the assembly process.
  • This solid block material 12' initially totally encloses the anodes 14, 14' and bolts 16, and is suspended by hangers 50 from the steel plate 18.
  • the alumina content of the block is adjusted to allow the assembly to withstand preheating temperatures.
  • the bath weight ratio (NaF ⁇ AlF 3 ) is preferably about 1.2 to 1.6 to withstand preheat temperatures.
  • the system 10 When the anode is set, some of the solid material 12' dissolves in the bath, exposing the lower part of the anode for electrolysis, while the upper part remains solid, like a natural crust, to provide insulation and protection from fumes. This crust will grow and shrink as the anode is raised and lowered, providing continuous protection and insulation.
  • the system 10 When the system 10 is set in the molten bath 34, as shown in Fig. 4 , it automatically provides the only two materials which need be added to the bath: alumina and more bath to fill the gaps between anodes 14 and 14'.
  • commercial aluminum can have a maximum of about 0.3 to 0.65% impurities; where the allowable range of each impurity is from about 0.1% to 0.6% Fe; 0% to 0.05% Cu; 0% to 0.05% Zn; 0% to 0.05% Ni; and 0% to 0.35% Si.
  • Use of alumina, Al 2 O 3 , or bath + alumina support, plus, in both cases, any associated alumina based cement material will allow the production of commercial grade aluminum.
  • the castable bath + alumina solid structure 12' usually comprises from about 40 wt.% to about 80 wt.%, preferably from about 55 wt.% to about 70 wt.% sodium aluminum fluoride powder; from about 2 wt.% to about 25 wt.%, preferably about 2 wt.% to about 10 wt.% aluminum oxide powder (Al 2 O 3 ).
  • the materials usually contain a minor effective amount of binder, usually from about 5 wt.% to about 25 wt.%; preferably from about 5 wt.% to about 15 wt.% of a cementitious material preferably an alumina based refractory cementitious material/cement, preferably containing from about 65 wt.% to 85 wt.% alumina (Al 2 O 3 ) and 15 wt.% to 30 wt.% CaO.
  • This cementitious material is a high temperature resistant material capable of resisting temperatures of from 800°C to 1200°C without degredation.
  • the usual components could include for example CaO, SiO 2 , Na 2 O, and Fe 2 O 3 .
  • the structure 12' may also contain minor amounts of Na 5 Al 3 F 14 (natural chiolite). Water is added to the powder mixture to make a slurry and then approximately 10 wt.% based on the entire powder mixture of the alumina based cementitious material is added to bind the bath + alumina material together. This bath material + cement slurry is then poured into a mold containing the inert anodes 14, 14' and hangers 50, followed by baking at approximately 125°C to 175°C for 10 hours to 15 hours to remove moisture. This provides a less porous, less temperature resistant structure than the purified alumina + cement structure, but is still preferred as chemically more similar to the electrolyte.
  • the alumina material can be molded, cast, dipped or sprayed. It is essentially pure Al 2 O 3 alone or mixed with a suitable cementitious binder based on alumina, with from about 5 wt.% to about 15 wt.% heat resistant, high temperature (capable of resisting temperatures of from about 800°C to 1200°C without degredation) cementitious material.
  • An anode system was provided with a solid circumscribing material containing a mixture of cryolite, calcium aluminate cement and dispersant as described below.
  • the water base mixture was then transferred to a container, to allow anodes to be dip coated with an up to 1 ⁇ 2 inch (1.27 cm) thick coat of the mixture.
  • anodes were lowered slowly into the mixture refractory coating until completely submerged.
  • the coating was allowed to equilibrate (that is, even out in the area that was in immediate contact with the anodes).
  • the anodes were then pulled out at a rate of about 12.5 cm/minute to allow at least a 0.6 cm thick coat of the bath block refractory to adhere to the surface of the anodes.
  • the anodes were then suspended from a fixture and a hot air dryer is used to accelerate the drying of the bath block coating. Once the outer surface was dry to the touch, the anodes were submerged for the second and third coat, as required, for specified coating applications with the appropriate drying step before the application of the next coat. To get a complete block structure several more applications would be required.
  • the anodes having the desired coating thickness were then placed in a preheating furnace, and heated to approximately 960°C at a rate to prevent cracking of the anode and insulating coating. Once at a desired temperature, the coated anodes were removed from the heater and quickly transferred to a Hall Cell with a loss of less than 10°C in temperature in less than the 2 minutes required to transfer the anodes into the Hall Cell.
  • the bath block coating was dissolved up to the bath line in less than 5 minutes.
  • the dissolution of the bath block from the submerged portion of the anode allowed current to flow for the production of aluminum metal.
  • the dissolved bath block insulation was of such composition that it didn't contaminate the metal or the cryolite used in the Hall Cell. This provided a simple, inexpensive compatible anode support useful for aluminum production.

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

Claims (10)

  1. Appareil d'électrolyse comprenant un système d'anode inerte comprenant au moins une anode inerte ayant une partie inférieure en contact avec un bain de sel fondu, où au moins une partie supérieure de l'anode inerte est en contact et est circonscrite par une matière solide soumise à une attaque par des gaz provenant du bain, la matière solide étant choisie dans le groupe consistant en un ciment à base d'alumine et de la cryolite-alumine, dont les deux se dissoudront en présence du bain de sel fondu.
  2. Appareil d'électrolyse selon la revendication 1, où la matière solide consiste en environ 40 % en poids à 80 % en poids de cryolite, environ 2 % en poids à 25 % en poids d'alumine, et 5 % en poids à 25 % en poids d'une matière cimentaire.
  3. Appareil d'électrolyse selon la revendication 1 ou la revendication 2, dans lequel l'appareil d'électrolyse est une culture électrolytique appropriée pour la production d'aluminium.
  4. Appareil d'électrolyse selon l'une quelconque des revendications précédentes, dans lequel la matière solide se dissoudra dans la mesure où l'épaisseur de matière solide restante est de 30 % à 80 % de l'épaisseur initiale.
  5. Appareil d'électrolyse selon l'une quelconque des revendications précédentes, dans lequel la matière solide se dissoudra dans la mesure où l'épaisseur de matière solide restante est de 40 % à 70 % de l'épaisseur de support initiale.
  6. Appareil d'électrolyse selon l'une quelconque des revendications précédentes, dans lequel la matière de ciment est un ciment réfractaire à base d'alumine.
  7. Appareil d'électrolyse selon l'une quelconque des revendications précédentes, dans lequel la totalité d'au moins une anode inerte est circonscrite par la matière solide.
  8. Appareil d'électrolyse selon l'une quelconque des revendications précédentes, où la matière solide est appliquée par coulée.
  9. Appareil d'électrolyse selon l'une quelconque des revendications précédentes, où la matière solide est appliquée par pulvérisation.
  10. Appareil d'électrolyse selon l'une quelconque des revendications précédentes, où la matière solide est appliquée par immersion.
EP13183888.0A 2002-11-25 2003-11-19 Ensemble a anode inerte Expired - Lifetime EP2688130B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
SI200332555T SI2688130T1 (en) 2002-11-25 2003-11-19 Inert anode composition

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US42881802P 2002-11-25 2002-11-25
EP03786931.0A EP1588443B1 (fr) 2002-11-25 2003-11-19 Ensemble a anode inerte

Related Parent Applications (2)

Application Number Title Priority Date Filing Date
EP03786931.0A Division EP1588443B1 (fr) 2002-11-25 2003-11-19 Ensemble a anode inerte
EP03786931.0A Division-Into EP1588443B1 (fr) 2002-11-25 2003-11-19 Ensemble a anode inerte

Publications (2)

Publication Number Publication Date
EP2688130A1 EP2688130A1 (fr) 2014-01-22
EP2688130B1 true EP2688130B1 (fr) 2017-07-26

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EP13183888.0A Expired - Lifetime EP2688130B1 (fr) 2002-11-25 2003-11-19 Ensemble a anode inerte

Country Status (6)

Country Link
EP (1) EP2688130B1 (fr)
CN (1) CN100515546C (fr)
ES (1) ES2644864T3 (fr)
NO (1) NO20052924D0 (fr)
RU (1) RU2293143C1 (fr)
SI (1) SI2688130T1 (fr)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101709485B (zh) * 2009-12-18 2012-07-04 中国铝业股份有限公司 一种采用惰性阳极生产原铝的铝电解槽
CN101942677A (zh) * 2010-09-30 2011-01-12 中南大学 一种铝电解惰性阳极用保温包覆材料及其应用
WO2016039978A1 (fr) * 2014-09-08 2016-03-17 Alcoa Inc. Appareil d'anode
RU2720129C2 (ru) * 2016-01-26 2020-04-24 АЛКОА ЮЭсЭй КОРП. Узел изоляции для электролизера

Family Cites Families (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1046705A (en) * 1964-05-27 1966-10-26 British Aluminium Co Ltd Improvements in or relating to the operation of electrolytic reduction cells for theproduction of aluminium
CH579155A5 (fr) * 1971-11-16 1976-08-31 Alusuisse
US4057480A (en) * 1973-05-25 1977-11-08 Swiss Aluminium Ltd. Inconsumable electrodes
GB2062862B (en) 1979-11-08 1984-03-14 Sumitomo Metal Ind Fully automatic ultrasonic flaw detection apparatus
IN169360B (fr) * 1987-12-22 1991-09-28 Savoie Electrodes Refract
DE3838828A1 (de) * 1988-11-17 1990-05-23 Vaw Ver Aluminium Werke Ag Kohleelektrode mit gasdichter, temperaturbestaendiger schutzglocke
US5279715A (en) 1991-09-17 1994-01-18 Aluminum Company Of America Process and apparatus for low temperature electrolysis of oxides
GB9511692D0 (en) 1995-06-09 1995-08-02 Fosbel Int Ltd A process for forming a refractory repair mass
US5865980A (en) * 1997-06-26 1999-02-02 Aluminum Company Of America Electrolysis with a inert electrode containing a ferrite, copper and silver
US6372119B1 (en) 1997-06-26 2002-04-16 Alcoa Inc. Inert anode containing oxides of nickel iron and cobalt useful for the electrolytic production of metals
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
US6217739B1 (en) 1997-06-26 2001-04-17 Alcoa Inc. Electrolytic production of high purity aluminum using inert anodes
US6551489B2 (en) * 2000-01-13 2003-04-22 Alcoa Inc. Retrofit aluminum smelting cells using inert anodes and method
DE60108085T2 (de) 2000-02-24 2005-12-15 Alcoa Inc. Procede de conversion de cellules de hall-heroult en cellules a anodes inertes
US20030209426A1 (en) * 2000-12-08 2003-11-13 Slaugenhaupt Michael L. Insulating lid for aluminum production cells

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
None *

Also Published As

Publication number Publication date
EP2688130A1 (fr) 2014-01-22
NO20052924L (no) 2005-06-15
NO20052924D0 (no) 2005-06-15
CN100515546C (zh) 2009-07-22
SI2688130T1 (en) 2018-06-29
ES2644864T3 (es) 2017-11-30
CN1917933A (zh) 2007-02-21
RU2293143C1 (ru) 2007-02-10

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