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WO1993010281A1 - Cellule d'electrolyse d'alumine, de preference a basse temperature - Google Patents

Cellule d'electrolyse d'alumine, de preference a basse temperature Download PDF

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Publication number
WO1993010281A1
WO1993010281A1 PCT/EP1992/002666 EP9202666W WO9310281A1 WO 1993010281 A1 WO1993010281 A1 WO 1993010281A1 EP 9202666 W EP9202666 W EP 9202666W WO 9310281 A1 WO9310281 A1 WO 9310281A1
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WO
WIPO (PCT)
Prior art keywords
anodes
cathodes
electrolyte
aluminium
cell according
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.)
Ceased
Application number
PCT/EP1992/002666
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English (en)
Inventor
Vittorio De Nora
Jean-Jacques Duruz
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Moltech Invent SA
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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
Priority claimed from PCT/EP1991/002219 external-priority patent/WO1992009724A1/fr
Application filed by Moltech Invent SA filed Critical Moltech Invent SA
Priority to DE69210038T priority Critical patent/DE69210038T2/de
Priority to US08/636,895 priority patent/US5725744A/en
Priority to EP92923752A priority patent/EP0613504B1/fr
Priority to CA002123417A priority patent/CA2123417C/fr
Priority to AU29440/92A priority patent/AU659247B2/en
Publication of WO1993010281A1 publication Critical patent/WO1993010281A1/fr
Priority to NO941882A priority patent/NO309155B1/no
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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Classifications

    • 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

Definitions

  • the invention relates to a cell for producing aluminium by electrolysis of alumina dissolved in a molten halide electrolyte particularly at temperatures between 680°-880°C.
  • Aluminium is produced by the Hall-Heroult process which involves the electrolysis of alumina dissolved in molten cryolite (Na 3 lFg) at about 960°C using carbon anodes which are consumed with the evolution of CO2.
  • the process suffers from major disadvantages.
  • the high cell temperature is necessary to increase the solubility of alumina and its rate of dissolution so that sufficient alumina can be maintained in solution, but requires heavy expenditure of energy.
  • the electrolyte and the molten aluminium aggressively react with most materials including ceramic and carbonaceous materials, and this creates problems of containment and cell design.
  • the anode-cathode distance is critical and has to be maintained high due to the irregular movement of the molten aluminium cathode pool, and this leads to loss of energy. Since the anodes are continually being consumed, this creates problems of process control. Further, the back oxidation of Al to Al 3+ decreases the current efficiency. Potentially, the electrolysis of alumina at low temperatures (below 880°C) in halide melts has several distinct advantages over the conventional Hall-Heroult process operating at about 960°C.
  • electrolysis at reduced current densities in low temperature melts potentially offers a significant advantage in increasing the stability of electrode materials, but it has not yet proven possible to implement the process in a way where this advantage could be realised in larger scale cells and in commercial cells.
  • Other potential advantages are higher current and energy efficiencies and the possibility of designing a completely enclosed electrolytic cell.
  • Low temperature alumina electrolysis has been described in US Patent No 3,951,763 and requires numerous expedients such as the use of a special grade of water- containing alumina to protect the carbon anodes, and the bath temperature had to be 40°C or more above the liquidus temperature of the Na 3 lFg/ lF 3 system in an attempt to avoid crust formation on the cathode. In practice. however, the carbon anodes were severely attacked during anode effects accompanied by excessive CF 4 emissions.
  • US Patent 4,681,671 proposed an important new principle for the production of aluminium by electrolysis of alumina dissolved in a molten fluoride-based electrolyte in an aluminium reduction cell, at a temperature below 900°C, by effecting steady-state electrolysis using an oxygen-evolving anode at an anode current density at or below a threshold value corresponding to the maximum transport rate of oxide ions in the electrolyte and at which oxide ions are discharged preferentially to fluoride ions.
  • That invention was based on the insight that oxide ions in low concentrations, as in the case of low temperature melts, could be discharged efficiently provided the anode current density did not exceed the given threshold. Exceeding this value would lead to the discharge of fluoride ions which had been observed in experiments using carbon anodes.
  • the electrolytic alumina reduction cell for carrying out the method contained a molten fluoride-based electrolyte with dissolved alumina at a temperature below 900°C, an inert oxygen-evolving anode and a cathode.
  • the anode had an electroche ically active surface area sufficiently large to allow it to operate with an anode current density at or below the given threshold.
  • the low temperature electrolyte was circulated from an electrolysis zone to an enrichment zone and back, to facilitate and speed up the solution rate of alumina.
  • the preferred cell design had vertical anodes in parallel spaced apart relationship above a horizontal drained cathode having holes for the upward circulation of electrolyte and through which the produced aluminium could drain to the bottom of the cell.
  • This design it was proposed to lower the anode current density to values compatible with low temperature operation, usually while maintaining the cathode current density at conventional values. The aim was to maintain a satisfactory production of aluminium per unit floor surface, enabling the process to operate economically.
  • the electrolyte In electrolysis cells for the production of aluminium by the electrolysis of alumina dissolved in a molten salt electrolyte containing halogen compounds, the electrolyte has an electrical resistivity substantially higher than that of the anode or cathode materials utilizing carbonaceous or substantially non-consumable material made of electrically conductive material resistant to the electrolyte and to the products of electrolysis.
  • Such increase can be obtained by increasing, according to the present invention, that part of the active surface area of the anode which faces the active surface area of the cathode and which is substantially parallel to such surface area.
  • the active surface areas are positioned preferably substantially upright or at a slope so that their horizontal projected area is only a fraction of the active surface areas.
  • An object of the invention is thus to provide an electrolysis cell for the production of aluminium by the electrolysis of alumina dissolved in a molten salt electrolyte containing halides, preferably at a temperature below 880°C, using substantially non- consumable anodes cooperating with a cathode arrangement, wherein high cell productivity can be attained by using anodes and cathodes in a configuration enabling effective use of large anode and cathode surfaces.
  • facing electrodes with appropriate large surface areas, it is also possible to operate with electrolytes (fluorides, mixed fluoride-chlorides, or chlorides) that could not hitherto effectively be used as a carrier for alumina to be electrolysed, on account of the low solubility.
  • electrolytes fluorides, mixed fluoride-chlorides, or chlorides
  • This new arrangement has the advantage that it can make use of existing anode and cathode materials that can withstand the operating conditions at lower current densities at the same temperature (usually about 940- 960°C) or at lower temperatures (below about 880°C) , but which failed in the more aggressive higher temperature baths at the usual high current densities necessary to achieve an acceptable production rate in the conventional cell designs.
  • the arrangement is particularly advantageous at lower temperatures, but can still be operated advantageously at higher temperatures, because the low current density operation enables the use of anode materials that could not withstand operation at higher current densities in high temperature molten electrolytes.
  • the anode current density By suitably lowering the anode current density and maintaining an uniform current distribution over the large anode surface area with the new cell design, many anode materials which fail at the usual high current densities
  • the current efficiency would be at least as high as in Hall-Heroult cells, usually higher, and the energy efficiency would be significantly improved by 20 to 30% compared to Hall-Heroult cells particularly because of the low current density and the reduced anode-cathode distance at which the ultipolar cells according to the present invention can efficiently operate.
  • the multimonopolar arrangement of anodes and cathodes can have means for electrical connection to the anodes at the top of the cell, and means for electrical connection to the cathodes at the bottom of the cell.
  • the bottom ends of the cathodes dip into a cathodic aluminium layer on the bottom of the cell, the cell bottom having a current collector bar or similar means for providing electrical connection of the aluminium layer to an external cathodic current supply.
  • the anodes and cathodes may be substantially vertical plates with the cathodes separated from the anodes by a
  • At least the operative surfaces of the anodes and possibly also of the cathodes are high surface
  • the anodes and possibly also the cathodes advantageously have a central current feeder carrying a porous active part on its opposite faces .
  • the pore sizes of such structures may for example range from 1
  • the spacing between the facing active anode and cathode surfaces is preferably arranged to allow solely an upward circulation of electrolyte in this space by gas lift, and spaces are provided outside the multimonopolar
  • 25 multimonopolar arrangements of anodes and cathodes can be arranged side-by-side with the spaces therebetween.
  • This electrolyte recirculation arrangement promotes the dissolution of alumina.
  • To replenish the electrolyte alumina can be fed into these spaces by any suitable means
  • the cell may be provided with electrolyte circulation guide means adjacent the edges of the facing anodes and cathodes,
  • the electrolyte circulation guide means comprise plates of electrically non-conductive material, possibly of alumina, arranged generally perpendicular to and on either side of the multimonopolar arrangement of anodes and cathodes.
  • the total facing active surface areas of the anodes and the corresponding facing active surface areas of the cathodes is many times, preferably at least 1.5 times and possibly much greater than the horizontal projected area of the anodes and cathodes onto the cell floor area, i.e. the area of the cell bottom covered by the vertical shadow on the cell bottom of an area enclosed by a line surrounding all of the anodes and cathodes. In this way, high cell productivity per unit floor area can be achieved even at very low current densities.
  • the electrolyte may be a fluoride melt, a mixed fluoride-chloride melt or a chloride melt.
  • Suitable fluorides are NaF, AIF 3 , MgF 2 , LiF, KF and CaF 2 in suitable mixtures.
  • the electrolyte may comprise a mixture of 42-63 wt% AIF 3 with up to 48 wt% NaF, and up to 48 wt% LiF, at a temperature in the range of 680°-880°C, preferably 700°- 860°C.
  • fluoride-based molten salt is about 35 wt% lithium fluoride, about 45 wt% magnesium fluoride and about 20 wt% calcium fluoride, which melt has a solidus temperature of approximately 680°C.
  • alkali and alkaline earth metal chlorides include alkali and alkaline earth metal chlorides, and Group III metal chlorides, eg. lithium, sodium and potassium chlorides, magnesium and calcium chlorides and aluminium chloride alone or mixed with alkali and alkaline earth metal fluorides, and Group III metal fluorides, eg. lithium, sodium and potassium fluorides, magnesium and calcium fluorides and aluminium fluorides.
  • the chlorides are, in general, less chemically aggressive than the fluorides, but the solubility of alumina is also lower.
  • An example of a chloride-based molten electrolyte comprises from about 0.5 to about 15 wt% aluminium chloride, from about 3 to about 40 wt% of an alkaline earth metal chloride selected from barium, calcium, magnesium, and strontium chlorides, from about 10 to 90 % lithium chloride and from about 10 to 80 wt% sodium chloride, with a NaCl/LiCl ratio of about 2.33.
  • This electrolyte is molten at about 650°C.
  • Lithium-based low temperature electrolytes are advantageous ' because lithium penetrates carbon preferentially to sodium, thereby reducing damage by sodium intercalation. Also the lithium may act as dopant for some ceramic oxides used as anode materials, or to prevent dissolution of a lithium dopant from a lithium- doped ceramic oxide used as anode material, and furthermore lithium increases the electrical conductivity of the melt .
  • the alumina can be present in the molten salt at a concentration of about 0.1 to about 5% by weight, often from 1% to 4.5%, as compared to 10% for a standard cryolite bath at the usual Hall-Heroult operating temperature of about 960°C.
  • Part of the alumina in the low temperature bath can be present as undissolved, solid suspension; this is expecially so for chloride baths with very low alumina solubilites.
  • mixed fluoride-chloride baths include one or more of the fluorides of sodium, potassium, lithium, calcium and aluminium with one or more chlorides of the same elements, typically with 90-70% by weight of fluorides for 10-30% by weight of chlorides.
  • FIG. 1 is a cross-section through part of a first embodiment of a multimonopolar cell according to the invention ;
  • FIG. 2 is a similar view of a second embodiment of a multimonopolar cell
  • Figure 3 illustrates a possible arrangement of the cells of Figures 1 and 2 to provide for electrolyte circulation and alumina replenishment
  • FIG. 4 is a schematic side elevation showing different forms of spacers arranged to promote electrolyte re—circulation
  • FIG. 5 is a schematic plan view showing different forms of members arranged to promote electrolyte re-circulation
  • FIG. 6 is a schematic plan view showing another arrangement for promoting electrolyte re ⁇ circulation.
  • FIG. 5 is a schematic illustration of the electrolyte circulation with the arrangement of Figure 6.
  • Fig. 1 shows a cell design with anodes and cathodes in the form of plates .
  • vertical cathode plates 1 and anode plates 2 are held apart in spaced parallel relationship by spacers 5.
  • the cathode plates 1 extend downwardly from the bottom of the anode plates 2 and dip in a pool 4 of cathodic aluminium on the cell bottom 7.
  • This cell bottom 7 contains collector bars (not shown) for the supply of current to the cathode.
  • the tops of the cathode plates 1 are located below the level 6 of electrolyte 3 which advantageously is one of the aforementioned halide-based electrolytes containing dissolved alumina at a temperature up to 880°C.
  • the anode plates 2 extend up from the top of the cathode plates 1, to above the electrolyte level 6, and are connected by any convenient means to buswork, not shown, for supplying anodic current.
  • the level of the aluminium pool 4 may fluctuate in use, but always remains below the bottom of anode plates 2.
  • the spacers 5 occupy only a small part of the facing anode/cathode surfaces, leaving the main part of these facing surfaces separated by an electrolysis space containing electrolyte 3.
  • the spacers 5 are located along the opposite edges of the facing anodes/cathodes.
  • the spacers 5 can be made of any suitable electrically non-conductive material resistant to the electrolyte and to the products of electrolysis, including silicon nitride and aluminium nitride.
  • Alumina particularly that calcined at high temperature, can also be used, on account of the low solubility of alumina in the melt and operation with the dissolved alumina at or near saturation, with continuous or intermittent replacement of the depleted alumina.
  • the anode plates 2 may be made of porous, reticulated, skeletal or multicellular material, or may be ribbed, louvered or otherwise configured to increase their active surface area relative to their geometrical area.
  • any substantially non consumable ceramic, cermet or metal can be used, possibly coated with a protective layer such as cerium oxyfluoride.
  • the anodes can for instance be made of Sn ⁇ 2 ⁇ based materials, nickel ferrites, metals such as copper and silver or alloys such as Ni-Cu alloy or INCONELTM, possibly coated with a protective coating.
  • Composite structures can also be used, for instance a Ni-Cu alloy on a Ni-Cr substrate, or composite structures of oxidised copper/nickel on a substrate which is an alloy of chromium with nickel, copper or iron and possibly other components, as described in US Patent N° 4,960,494.
  • the cathode plates 1 are normally solid but porous cathode plates may also be used.
  • the main requirement for the cathode configura ion is that it should ensure homogeneous current distribution over the entire anode active surface area. Thus, in most cases, flat facing anodes and cathodes of equal sizes will be preferred.
  • the described cell configuration leads to a high productivity of aluminium per unit area of the cell bottom at low current densities, because large facing anode/cathode plates can be used, as more fully explained below.
  • Fig. 2 is a similar view of another multimonopolar cell, the same parts as before being designated by the same references.
  • the anodes 2 are composite structures each having a current feeder 12 made of a suitable metal alloy sandwiched between high surface area operative anode faces 13, for instance having a porous, reticulated structure.
  • porous anode faces 13 can be made of or coated with a refractory oxycompound coating.
  • the current feeder 12 and the reticulated faces 13 can -be made of the same or a similar metallic alloy having an excellent electrical conductivity, and the reticulated structure can be coated with a cerium oxyfluoride based protective layer applied ex situ, or formed in the cell.
  • the resistivity of the reticulated faces 13 is closer to that of the electrolyte 3, which ensures an even current distribution throughout the structure over a high surface area, therefore a very low effective anodic current density.
  • the current feeder 12 of metallic alloy ensures even current distribution all over the active surface area of the anodes 2, while minimising the voltage drop across the electrodes.
  • the spacer 5 may be in the form of a porous diaphragm between the operative anode and cathode faces.
  • Such diaphragm may be made of silicon nitride, aluminium nitride, alumina or similar electrically non-conductive material resistant to the electrolyte 3 and to the products of electrolysis in the operating conditions. Its pores are of adequate size to allow passage of the electrolyte 3.
  • the cathodes 1 in this cell are porous bodies, for example of reticulated structure whose bottom ends dip into the cathodic aluminium pool 4 on the cell bottom 7.
  • These porous cathode bodies can be made of or coated with an aluminium-wettable refractory hard material such as TiB 2 • It is possible to provide the cathodes 1 with a central current feeder plate (not shown) , like the anodic current feeders 12.
  • the anode-cathode assemblies of Figs. 1 and 2 are vertical in the cell. But they could if required be inclined to the vertical at a suitable slope, usually up to 30° off vertical and even 45°.
  • electrolysis current passes between the facing operative anode and cathode surfaces which are parallel or substantially parallel surfaces arranged upright in the cell, or at a convenient sloping angle. Because of this configuration, the total operative anode and cathode surface area can be many times greater than the underlying area of the cell bottom 7. In this way, it is possible to operate the cell at comparatively low anodic current densities, compatible with the usual low operating temperatures and the corresponding low alumina solubilities, while achieving an acceptable productivity per unit floor area.
  • this electrolyte circulation is provided by making use of the gas lift effect.
  • the anodically released gas oxygen with an oxide-containing electrolyte
  • electrolyte 3 between the anodes 2 and cathodes 2. Because of the small anode-cathode gap, there is no downward circulation of electrolyte in the anode-cathode gap.
  • Fresh alumina can be supplied to these spaces to compensate for depletion during electrolysis.
  • the high electrolyte circulation rate promoted by gas lift enhances the rate of alumina dissolution, compared to conventional cells.
  • Such an arrangement may have several multimonopolar rows of anodes 2 and cathodes 1 spaced across the width or along the length of the cell, with a space 20 between the adjacent rows and also adjacent the sidewalls 21 of the cell.
  • the cell could have a single row of multimonopolar anodes and cathodes along its length, with recirculation spaces on either side and/or at the ends of the cell.
  • electrolyte 3 is circulated as indicated by arrows 22 up between the opposite active surfaces of the anodes 2 and cathodes 1, and down in the spaces 20.
  • the gas lift effect can be assisted by forced circulation using a pump made of alumina or other electrolyte-resistant material.
  • Alumina is fed to the spaces 20 as indicated by arrows 23 at a rate to compensate for depletion during electrolysis.
  • This rate can be calculated from the cell's current consumption and can, if necessary, be monitored by measuring the alumina concentration of the cell periodically, for instance by the method disclosed in Italian Patent Application 21054.
  • the anodes 2 can if required be provided with vertical grooves or ribs to assist the gas release.
  • Circulation of the electrolyte can be enhanced by circulation guide means, possibly formed by the spacers 5, adjacent the edges of the facing anodes and cathodes of each multimonopolar stack, as illustrated in Figs. 4 to 7.
  • Fig. 4 shows in side view several possible forms of spacers: spacer 5 extends over the entire height of the anodes/cathodes; spacer 5a extends over a major part of the height, to near the top and bottom of the anodes/cathodes 1,2; and spacers 5b are spaced apart from one another over the height of the anodes/cathodes 1,2.
  • the plan view of Fig. 5 shows how these spacers 5 are located between the anodes 2 and cathodes 1 adjacent their edge.
  • the facing electrodes 1,2 are enclosed at their sides like a box, forcing the electrolyte flow up inside, and down outside.
  • discontinuous spacers like 5b are provided, this allows for some electrolyte intake from the sides.
  • Fig. 5 also shows alternative electrolyte guides which do not act as spacers, namely generally vertical bars 25 of triangular section, bars 26 of circular section and bars 27 of square or rectangular section. These bars are placed outside the anode-cathode space, allowing maximum use of the facing electrode surfaces. As shown for 25 and 26, the bars can be spaced from the edges of the facing electrodes 1,2 to allow controlled intake of electrolyte from outside. Or, as shown for the rectangular bar 27, the bars can contact the edges of the facing electrodes 1,2 to close the sides of the multimonopolar stack. As for the spacers 5, these bars 25,26,27 can extend over the entire height of the electrodes 1,2, or only a part of the height.
  • Figs. 6 and 7 show another arrangement for controlling the electrolyte flow path, namely plates 28 extending along each side of each multimonopolar stack of electrodes 1,2 over their entire height or, as shown in Fig. 7, over the major part of their height to just below the top and just above the bottom of the stack. These plates 28 can contact the edges of the electrodes 1,2 or can be spaced apart by a convenient disance.
  • Fig. 7 shows the upward electrolyte flow between the electrodes 1,2 and the downward flow outside the stack, as well as the alumina feed 23.
  • the bars 25,26,27 and plates 28 can all be made of the same electrically-resistant non-conductive materials as the spacers 5. By making the bars 25,26,27 and the plates 28 of alumina, which slowly dissolves in the molten electrolyte, this dissolution contributes to the alumina feed and the bars/plates can be replaced when necessary.
  • the gaps between the large faces of the anodes and cathode were 6mm.
  • Current was supplied at an anode and an equal cathode current density of 0.2A/cm 2 , this current flowing uniformly over the entire surfaces of the facing anodes and cathode.
  • the cell voltage was approximately 3.2V.
  • the gas lift during electrolysis was sufficient to circulate electroyte upwardly in the anode-cathode gaps, the electrolyte flowing down outside the electrodes.
  • Alumina powder was added outside the electrode during operation to maintain the alumina concentration in the anode-cathode gaps. Electrolysis was continued for 200 hours. The current efficiency was >90% .
  • This experiment demonstrates the advantages of facing vertical anode and cathode plates in a basic multimonopolar unit, which readily can be scaled up by multiplying the number of units and their sizes.
  • a second experiment using the cell design shown in Fig. I was carried out in a laboratory cell consisting of an alumina crucible of 12cm internal diameter heated in an electrical resistance furnace. Two plates of titanium diboride of 80mm length, 50mm width and 5mm thickness were used as vertical cathodes . Three plates of tin oxide of 120mm length, 50mm width and 5mm thickness were used as vertical anodes . Anodes and cathodes were held together at a 5mm interelectrode distance by means of two alumina plates 60mm high, 55mm wide and 10mm thick, each fitted with five vertical grooves into which the vertical edges of the cathodes and anodes were lodged.
  • the lower end of the cathodes rested on the crucible bottom and were dippping in a molten aluminum pad of 1 cm thickness which acted as the cathode current collector.
  • the upper parts of the anodes were held together by means of an Inconel 600TM block bolted to the anodes and which also served as the anode electrical contact and mechanical support.
  • the nominal electrolyte composition was 63% Na3AlF ⁇
  • the electrolyte temperature was 750°C.
  • the alumina solubility was approximately 4% by weight of the electrolyte.
  • the electroche ically active surface area of each anode and cathode face was 21.50 cm 2 and the total active surface was 86 cm 2 .
  • the vertically projected surface area of the anode-cathode assembly was approximately 23 cm 2 -
  • Efficient electrolyte circulation between the anodes and cathodes was achieved by the gas lift due to the oxygen evolution at the surface of the anodes. This effect was demonstrated by the fact that alumina powder feed was added outside the electrode system without significant drop in alumina concentration in the electrode gaps as evidenced by a stable voltage during the electrolysis. The electrolysis was continued for 100 hours. The current efficiency was about 88%. The cathodes after the experiment were completely wetted by aluminum indicating that the metal was drained from the cathode to the bottom of the cell. The relatively high current efficiency shows that no significant aluminum reoxidation by the evolving oxygen did occur.

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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)
  • Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)

Abstract

Cellule d'électrolyse destinée à la production d'aluminium par l'électrolyse d'alumine dissoute dans un électrode d'halogénure fondu, de préférence à une température inférieure à 880 °C et à l'aide d'un ensemble multimonopolaire d'anodes (2) et de cathodes (1) sensiblement non consommables dont les surfaces actives disposées en regard l'une de l'autre sont verticales ou inclinées, écartées l'une de l'autre et sensiblement parallèles, afin de permettre le fonctionnement à faible densité de courant de plaque tout en assurant un rendement acceptable pour chaque unité de surface horizontale occupée par la cellule. Les surfaces actives des anodes (2) et des cathodes (1) sont de taille importante grâce à leur configuration verticale ou inclinée. On peut agrandir les surfaces actives des anodes (2) et éventuellement celles des cathodes (1) en les rendant poreuses, de préférence à l'aide d'une structure fondamentale réticulée, et par exemple au moyen d'une partie active poreuse (13) placée sur les faces opposées d'un dispositif central d'alimentation en courant (12). Il se produit une circulation montante d'électrolyte due à la montée de gaz entre les électrodes. On a également prévu des dispositifs de guidage de la circulation d'électrolyte, par exemple des écarteurs (5) contigus aux bords des anodes (2) et cathodes (1) opposées.
PCT/EP1992/002666 1991-11-20 1992-11-19 Cellule d'electrolyse d'alumine, de preference a basse temperature Ceased WO1993010281A1 (fr)

Priority Applications (6)

Application Number Priority Date Filing Date Title
DE69210038T DE69210038T2 (de) 1991-11-20 1992-11-19 Zelle für die elektrolyse von tonerde,vorzugsweise bei niedrigeren temperaturen
US08/636,895 US5725744A (en) 1992-03-24 1992-11-19 Cell for the electrolysis of alumina at low temperatures
EP92923752A EP0613504B1 (fr) 1991-11-20 1992-11-19 Cellule d'electrolyse d'alumine, de preference a basses temperatures
CA002123417A CA2123417C (fr) 1991-11-20 1992-11-19 Pile pour l'electrolyse d'alumine preferablement a basses temperatures
AU29440/92A AU659247B2 (en) 1991-11-20 1992-11-19 Cell for the electrolysis of alumina preferably at low temperatures
NO941882A NO309155B1 (no) 1991-11-20 1994-05-19 Celle for elektrolyse av alumina fortrinnsvis ved lave temperaturer, og anvendelse av cellen

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
ATPCT/EP91/02219 1991-11-20
PCT/EP1991/002219 WO1992009724A1 (fr) 1990-11-28 1991-11-20 Ensembles d'electrodes et cellules multimonopolaires pour l'extraction electrolytique d'aluminium
EP92810212 1992-03-24
EP92810212.8 1992-03-24

Publications (1)

Publication Number Publication Date
WO1993010281A1 true WO1993010281A1 (fr) 1993-05-27

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PCT/EP1992/002666 Ceased WO1993010281A1 (fr) 1991-11-20 1992-11-19 Cellule d'electrolyse d'alumine, de preference a basse temperature

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AU (1) AU659247B2 (fr)
CA (1) CA2123417C (fr)
DE (1) DE69210038T2 (fr)
NO (1) NO309155B1 (fr)
WO (1) WO1993010281A1 (fr)

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5728466A (en) * 1995-08-07 1998-03-17 Moltech Invent S.A. Hard and abrasion resistant surfaces protecting cathode blocks of aluminium electrowinning cells
WO1999041429A1 (fr) * 1998-02-11 1999-08-19 Moltech Invent S.A. Cellules d'extraction electrolytique d'aluminium a cathode drainee presentant une distribution amelioree d'alumine
WO2000065130A1 (fr) * 1997-09-19 2000-11-02 Alcoa Inc. Circulation de bain de sels fondus destinee a une cuve d'electrolyse
WO2001031088A1 (fr) * 1999-10-26 2001-05-03 Moltech Invent S.A. Cellule d'extraction electrolytique d'aluminium a cathode drainee ameliorant la circulation de l'electrolyte
RU2220228C2 (ru) * 1999-04-28 2003-12-27 Алкоа Инк. Устройство для циркуляции ванны расплава солей в электролизере
RU2275443C2 (ru) * 2004-07-23 2006-04-27 Общество с ограниченной ответственностью "Инженерно-технологический центр" Многополярная электролизная ванна для получения жидких металлов электролизом расплавов и способ установки электролизных ванн
RU2287026C1 (ru) * 2005-06-03 2006-11-10 Государственное образовательное учреждение высшего профессионального образования "Пермский государственный университет" Многоячеистый электролизер с биполярными электродами для получения алюминия (электролизер кирко - полякова)
RU2422559C1 (ru) * 2010-02-10 2011-06-27 Федеральное агентство по образованию Государственное образовательное учреждение высшего профессионального образования "Уральский государственный горный университет" Устройство электролизеров
US8480876B2 (en) 2007-12-26 2013-07-09 Theodore R. Beck Aluminum production cell
RU2586183C1 (ru) * 2015-01-22 2016-06-10 Федеральное государственное автономное образовательное учреждение высшего образования "Сибирский федеральный университет" Электролизер для получения жидких металлов электролизом расплавов
CN114599820A (zh) * 2019-07-25 2022-06-07 力迈特集团公司 熔融盐膜电解槽
US12173420B2 (en) 2021-01-21 2024-12-24 Li-Metal Corp. Electrowinning cell for the production of lithium and method of using same
US12180602B2 (en) 2021-01-21 2024-12-31 Arcadium Lithium Intermediate Irl Limited Process for production of refined lithium metal
US12188140B2 (en) 2021-01-21 2025-01-07 Arcadium Lithium Intermediate Irl Limited Electrorefining apparatus and process for refining lithium metal

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US4402808A (en) * 1982-07-30 1983-09-06 Aluminum Company Of America Gasket for sealing joints between electrodes and adjacent cell lining and for improving bath circulation in electrolysis cells
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EP0126555A1 (fr) * 1983-04-26 1984-11-28 Aluminum Company Of America Cellule électrolytique et procédé
EP0192602A1 (fr) * 1985-02-18 1986-08-27 MOLTECH Invent S.A. Electrolyse d'alumine à basse température
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US4110178A (en) * 1977-05-17 1978-08-29 Aluminum Company Of America Flow control baffles for molten salt electrolysis
US4405433A (en) * 1981-04-06 1983-09-20 Kaiser Aluminum & Chemical Corporation Aluminum reduction cell electrode
US4402808A (en) * 1982-07-30 1983-09-06 Aluminum Company Of America Gasket for sealing joints between electrodes and adjacent cell lining and for improving bath circulation in electrolysis cells
EP0126555A1 (fr) * 1983-04-26 1984-11-28 Aluminum Company Of America Cellule électrolytique et procédé
EP0192602A1 (fr) * 1985-02-18 1986-08-27 MOLTECH Invent S.A. Electrolyse d'alumine à basse température
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US5728466A (en) * 1995-08-07 1998-03-17 Moltech Invent S.A. Hard and abrasion resistant surfaces protecting cathode blocks of aluminium electrowinning cells
WO2000065130A1 (fr) * 1997-09-19 2000-11-02 Alcoa Inc. Circulation de bain de sels fondus destinee a une cuve d'electrolyse
AU764187B2 (en) * 1997-09-19 2003-08-14 Alcoa Inc. Molten salt bath circulation design for an electrolytic cell
WO1999041429A1 (fr) * 1998-02-11 1999-08-19 Moltech Invent S.A. Cellules d'extraction electrolytique d'aluminium a cathode drainee presentant une distribution amelioree d'alumine
RU2220228C2 (ru) * 1999-04-28 2003-12-27 Алкоа Инк. Устройство для циркуляции ванны расплава солей в электролизере
WO2001031088A1 (fr) * 1999-10-26 2001-05-03 Moltech Invent S.A. Cellule d'extraction electrolytique d'aluminium a cathode drainee ameliorant la circulation de l'electrolyte
RU2275443C2 (ru) * 2004-07-23 2006-04-27 Общество с ограниченной ответственностью "Инженерно-технологический центр" Многополярная электролизная ванна для получения жидких металлов электролизом расплавов и способ установки электролизных ванн
RU2287026C1 (ru) * 2005-06-03 2006-11-10 Государственное образовательное учреждение высшего профессионального образования "Пермский государственный университет" Многоячеистый электролизер с биполярными электродами для получения алюминия (электролизер кирко - полякова)
US8480876B2 (en) 2007-12-26 2013-07-09 Theodore R. Beck Aluminum production cell
RU2422559C1 (ru) * 2010-02-10 2011-06-27 Федеральное агентство по образованию Государственное образовательное учреждение высшего профессионального образования "Уральский государственный горный университет" Устройство электролизеров
RU2586183C1 (ru) * 2015-01-22 2016-06-10 Федеральное государственное автономное образовательное учреждение высшего образования "Сибирский федеральный университет" Электролизер для получения жидких металлов электролизом расплавов
CN114599820A (zh) * 2019-07-25 2022-06-07 力迈特集团公司 熔融盐膜电解槽
US12173420B2 (en) 2021-01-21 2024-12-24 Li-Metal Corp. Electrowinning cell for the production of lithium and method of using same
US12180602B2 (en) 2021-01-21 2024-12-31 Arcadium Lithium Intermediate Irl Limited Process for production of refined lithium metal
US12180603B2 (en) 2021-01-21 2024-12-31 Arcadium Lithium Intermediate Irl Limited Process for production of refined lithium metal
US12188140B2 (en) 2021-01-21 2025-01-07 Arcadium Lithium Intermediate Irl Limited Electrorefining apparatus and process for refining lithium metal
US12188141B2 (en) 2021-01-21 2025-01-07 Arcadium Lithium Intermediate Irl Limited Electrowinning cell for the production of lithium and method of using same

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NO941882D0 (no) 1994-05-19
CA2123417C (fr) 1999-07-06
AU2944092A (en) 1993-06-15
CA2123417A1 (fr) 1993-05-27
DE69210038D1 (de) 1996-05-23
NO309155B1 (no) 2000-12-18
NO941882L (no) 1994-05-19
AU659247B2 (en) 1995-05-11
DE69210038T2 (de) 1996-09-05

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