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EP0217438B2 - Process and apparatus for manufacturing very pure lithium by molten salt electrolysis - Google Patents
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EP0217438B2 - Process and apparatus for manufacturing very pure lithium by molten salt electrolysis - Google Patents

Process and apparatus for manufacturing very pure lithium by molten salt electrolysis Download PDF

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Publication number
EP0217438B2
EP0217438B2 EP86201529A EP86201529A EP0217438B2 EP 0217438 B2 EP0217438 B2 EP 0217438B2 EP 86201529 A EP86201529 A EP 86201529A EP 86201529 A EP86201529 A EP 86201529A EP 0217438 B2 EP0217438 B2 EP 0217438B2
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European Patent Office
Prior art keywords
electrolytic cell
lithium
lithium metal
molten
electrolysis
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EP86201529A
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German (de)
French (fr)
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EP0217438A1 (en
EP0217438B1 (en
Inventor
Jürgen Dr. Müller
Richard Dr. Bauer
Bernd Sermond
Eike Dr. Dolling
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GEA Group AG
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Metallgesellschaft AG
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Priority to AT86201529T priority Critical patent/ATE48658T1/en
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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
    • C25C3/02—Electrolytic production, recovery or refining of metals by electrolysis of melts of alkali or alkaline earth metals

Definitions

  • the invention relates to a method for producing high-purity metallic lithium by melt flow electrolysis and to an electrolytic cell for carrying out the method.
  • Metallic lithium is obtained in technical practice by electrolysis of a molten mixture of lithium chloride and potassium chloride.
  • the potassium chloride portion is known to lower the melting point of the lithium chloride.
  • Suitable electrolysis cells are, for example, cells without a diaphragm. Such cells have a housing made of steel, a steel cathode and a graphite anode. The cell has no inner lining.
  • the molten metallic lithium collects on the surface of the molten salt. From there it is skimmed off using ladles, or it can also be pulled off by lifting devices.
  • the developed and outflowing chlorine gas allows air to enter the cell, so that there is a risk of oxidation and nitridation of the liquid metal.
  • EP-OS 107 521 discloses a process for the continuous production of lithium metal by electrolysis of lithium chloride in a molten salt mixture in an electrolysis cell with a cylindrical steel cathode inserted into the cell bottom and a graphite anode immersed in the cylinder.
  • the lithium metal salt melt is removed from the cell and the lithium metal is separated outside the cell. Due to the chlorine gas development and the venturi-like end of the cathode, a natural circulation of the melt is brought about. A further reaction of the lithium metal should not take place in the melt mixture.
  • Contaminants of any kind are extremely undesirable in lithium metal if it is to be used for nuclear purposes, for the production of alloys and for lithium batteries.
  • the invention has for its object to provide a method for producing lithium metal of high purity and to provide a suitable device for performing the method.
  • the invention solves the problem with a method as set out in claim 1.
  • the lithium metal discharged is further processed in a manner known per se, for example cast into bars. While the electrolyte is being circulated in the electrolysis cell and returned to the electrode space, the anodically separated chlorine gas is sucked out of the covered gas space via the melt and obtained as such or in the form of salts.
  • the chlorine gas stream is expediently drawn through an absorption system charged with a slurry of lithium hydroxide, with the use of ammonia as a reducing agent in accordance with:
  • the lithium chloride obtained in this way again serves as a raw material for the electrolysis.
  • the metal-containing electrolyte directed into the separation space is created in the siphon-like pipe connection and that the metal / molten salt mixture rising in the electrode space is immediately discharged into the separation space. That is, there should neither be a separation in the electrolysis vessel which can be caused by an outflow velocity which is too low, nor a flow velocity which is too high, so that chlorine gas or air is drawn into the separation space.
  • the level of the electrolyte melt can also be kept constant by controlled immersion of a neutral body in the electrolyte melt. In the practical implementation of the method according to the invention, the ascending metal / molten salt mixture remains on the bath surface for about 2 seconds or less.
  • the electrolyte flow is at least partially caused by the “mammoth pump effect” of the rising chlorine gas and, furthermore, is generated by a pumping effect caused by mechanical means in the shorter leg of a siphon-like connecting tube between the electrolysis space or the annular space and the separation space.
  • Mechanical units known per se such as pumps or stirrers, are suitable for the mechanical generation of the electrolyte flow.
  • From the Separation space is, after building up a buffer volume of liquid lithium and cleaned by segregation, the lithium continuously discharged into a template and z. B. shed and let cool.
  • a protective gas atmosphere for example of argon, is maintained in the separation space above the melt level.
  • the invention further provides an electrolysis cell for carrying out the method according to the invention.
  • an electrolysis cell of the type mentioned at the outset for the electrolytic extraction of metallic lithium a steel cathode being welded to the bottom of the container in a cylindrical, closed electrolysis steel container, and the part of the graphite anode which is immersed in the molten salt and which is vertically and gas-tight against the atmosphere surrounds, as well as with organs for introducing lithium chloride, protective gas and for supplying electrical energy and for discharging lithium metal and chlorine gas.
  • the cylindrical steel container fulfills the task of a separating pipe or separator, d. H. liquid metallic lithium and electrolyte melt separate in it.
  • the separating tube therefore has a small diameter which is approximately 1/10 of the diameter of the electrolysis container.
  • the siphon-like tube which is connected on the one hand to the electrolysis cell or to the ring trough surrounding the upper cathode edge and on the other hand to the separating tube, has an essential function as an overflow tube for the metal / molten salt mixture.
  • a mechanical conveyor is arranged in the shorter leg of the siphon-like tube in order to generate a pump drum at the entrance of the U-tube or a flow directed into the separating tube. For the purposes of the invention, this includes, for example, agitators, such as propeller stirrers, screw conveyors or centrifugal pumps.
  • the drive means are inserted through the upper cover, through which an inlet for protective gas is also expediently guided.
  • the siphon-like tube (15) over its entire length, i. H. in the longer and shorter leg has the same diameter.
  • the longer leg (16a) or the suction pipe has a smaller diameter than the shorter leg.
  • the upper section of the shorter leg is expanded into a cylindrical part of larger diameter (16).
  • the ratio of smaller to larger diameter is 1: 2 to 1:12 and preferably 1: 5 to 1:10.
  • the graphite anode is inserted through the lid into the electrolysis vessel. It can be attached to the lid and protrude hanging into the cathode compartment. However, it is expediently passed through the lid in an insulating and easily replaceable manner and then sits on the iron container bottom via an electrically insulating molded part.
  • Such an insulating molded part advantageously consists of oxide-ceramic material, for example of molten aluminum oxide.
  • the insulating molded part is expediently protected against the corrosive attack of the molten electrolyte by partially solidified molten salt during cell operation. This is achieved by suitable temperature control.
  • the graphite anode can be designed as a solid plate or solid cylinder. Accordingly, the cathode is also designed as a box-shaped hollow cathode or as a hollow cylinder. The cathode and cell share the same potential. The negative pole of the voltage source is connected to the cell bottom.
  • the upper edge of the cathode protrudes beyond the level of the molten electrolyte.
  • the mammoth pump effect serves as the conveying force? »Of the rising chlorine gas.
  • the upper edge of the cathode is in the form of a ring gear.
  • the figure in the figure shows a device according to the invention.
  • the cathode 3 is arranged in the electrolysis cell 1 closed by cover 2 and welded to the bottom of the vessel.
  • the upper edge of the cathode 3 is provided with a collecting channel 4 for the molten salt metal which overflows.
  • the graphite anode 5 is inserted through the cover 2 and is seated on the bottom of the electrolytic cell 1 via the insulating body 6 and is surrounded by the cathode 3.
  • the positive pole of a DC power source is connected at 7 and the negative pole at 8.
  • the circulation of the molten electrolyte is made possible via the openings 9 in the lower part of the cathode wall.
  • lithium chloride is added to the molten salt mixture in accordance with the consumption charged. Developed chlorine gas escapes through the outlet 11.
  • a separating tube 12 which is closed with a lid 13, is also arranged.
  • the separating tube 12 is welded into the cover 2 of the electrolytic cell 1, protrudes above the cell and leads to the bottom of the cell 1.
  • openings 14 enable the molten salt to be balanced with the other molten electrolyte.
  • the separating pipe 12 is connected to the gutter 4 via the siphon-like connecting pipe 15.
  • the U-shaped connecting pipe 15 is inserted with its longer leg into the bottom of the gutter 4, while the opening of the shorter leg is widened to a larger pipe diameter 16.
  • a stirrer 17 is arranged in the tube part 16, the shaft of which is inserted through the cover 13 of the separating tube 12.
  • an inlet for protective gas is also attached.
  • the molten lithium metal is discharged from the separating tube via the tube 19.
  • the insulating shaped piece 6 is protected against corrosive attack by the melt by solidified melt 20.
  • a eutectic salt mixture of approximately 50% by weight lithium chloride and approximately 50% by weight potassium chloride serves as the electrolyte.
  • the operating temperature is 400 ° C.
  • the current density is 5,000 to 10,000 amps / m 2, preferably 6,000 amps / m 2 .
  • the cell voltage is accordingly 6.2 to 9.2 volts.
  • the current yield is over 90%.
  • Normal structural steel is used as the material for the cell and cathode.
  • the wall thickness of the cell is about 20 mm, the cell has no ceramic lining.
  • the anode made of electrographite is inserted centrally in the cathode compartment. The distance between the electrodes is about 50 mm.
  • the anodically separated chlorine collects in the gas space above the molten salt and is removed from the cell at a low vacuum.
  • the molten salt mixture containing lithium metal rising from the electrode space runs into the collecting trough.
  • the lithium metal, which is already partially floating there, is immediately conveyed to the inlet of the siphon-like pipe with a great deal of melt at high flow speed.
  • the high flow velocity in the U-tube is generated by a paddle mixer.
  • the metallic lithium separates from the molten salt mixture containing lithium metal under an argon atmosphere and floats, while the molten salt mixture leaves the separating tube in a downward flow and returns to the circuit.
  • the molten lithium metal collected cleans itself of further impurities by segregation and is discharged continuously or discontinuously and, in a manner known per se, processed further under suitable conditions, such as under a protective gas atmosphere or in vacuo.
  • the high purity lithium metal obtained by the process according to the invention has the following analysis:

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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)
  • Manufacture And Refinement Of Metals (AREA)

Abstract

This invention relates to a process of producing lithium metal by the electrolysis of fused mixed salts comprising electrolyzing fused mixed salts consisting of lithium chloride and potassium chloride in a diaphragmless electrolytic cell, withdrawing molten lithium metal from the cell to a receiver and cooling the lithium metal which has been withdrawn. To decrease the content of impurities in a continuous process, molten mixture which rises in the interelectrode space in the cell and contains lithium metal is collected in an annular zone, which surrounds the top end of the cathode adjacent to the surface level of the molten mixture, said molten mixture is withdrawn from said annular zone through a siphon pipe and is supplied from the latter to a separating chamber, which communicates with the electrolytic cell and is sealed from the chlorine gas atmosphere in the electrolytic cell, electrolyte and lithium are separated in the separating chamber under a protective gas atmosphere, lithium metal is discharged from the separating chamber into a receiver under a protective gas atmosphere, and the electrolyte is recycled from the separating chamber to the electrolytic cell. An electrolytic cell for carrying out the process is also described.

Description

Die Erfindung betrifft ein Verfahren zur Herstellung von hochreinem metallischen Lithium durch Schmelzflußelektrolyse sowie eine Elektrolysezelle zur Durchführung des Verfahrens.The invention relates to a method for producing high-purity metallic lithium by melt flow electrolysis and to an electrolytic cell for carrying out the method.

Metallisches Lithium wird in der technischen Praxis durch Elektrolyse eines schmelzflüssigen Gemischs von Lithiumchlorid und Kaliumchlorid gewonnen. Der Kaliumchloridanteil dient in bekannterweise der Erniedrigung des Schmelzpunktes des Lithiumchlorids. Geeignete Elektrolysezellen sind beispielsweise Zellen ohne Diaphragma. Derartige Zellen besitzen ein Gehäuse aus Stahl, eine Stahlkathode und eine Graphitanode. Die Zelle hat keine innere Ausmauerung. Das schmelzflüssige metallische Lithium sammelt sich auf der Oberfläche der Salzschmelze. Von dort wird es mittels Schöpfkellen abeschöpft, oder es kann auch durch Hebevorrichtungen abgezogen werden. Das entwickelte und abströmende Chlorgas ermöglicht den Zutritt von Luft zurZelle, so daß die Gefahr der Oxidierung und Nitridierung des Flüssigmetalls besteht. Aus EP-OS 107 521 ist ein Verfahren zur kontinuierlichen Herstellung von Lithiummetall durch Elektrolyse von Lithiumchlorid in einer geschmolzenen Salzmischung in einer Elektrolysezelle mit im Zellenboden eingeführter zylinderförmiger Stahlkathode und in den Zylinder eintauchender Graphitanode bekannt. Im vorbekannten Verfahren wird die lithiummetallhaltige Salzschmelze aus der Zelle abgeführt und das Lithiummetall außerhalb der Zelle abgetrennt. Aufgrund der Chlorgasentwicklung und des venturiartig ausgebildeten Endes der Kathode wird eine natürliche Zirkulation der Schmelze bewirkt. In der Schmelzenmischung soll eine Weiterraktion des Lithiummetalls nicht stattfinden.Metallic lithium is obtained in technical practice by electrolysis of a molten mixture of lithium chloride and potassium chloride. The potassium chloride portion is known to lower the melting point of the lithium chloride. Suitable electrolysis cells are, for example, cells without a diaphragm. Such cells have a housing made of steel, a steel cathode and a graphite anode. The cell has no inner lining. The molten metallic lithium collects on the surface of the molten salt. From there it is skimmed off using ladles, or it can also be pulled off by lifting devices. The developed and outflowing chlorine gas allows air to enter the cell, so that there is a risk of oxidation and nitridation of the liquid metal. EP-OS 107 521 discloses a process for the continuous production of lithium metal by electrolysis of lithium chloride in a molten salt mixture in an electrolysis cell with a cylindrical steel cathode inserted into the cell bottom and a graphite anode immersed in the cylinder. In the previously known method, the lithium metal salt melt is removed from the cell and the lithium metal is separated outside the cell. Due to the chlorine gas development and the venturi-like end of the cathode, a natural circulation of the melt is brought about. A further reaction of the lithium metal should not take place in the melt mixture.

Im Lithiummetall sind Verunreinigungen gleich welcher Art in höchstem Maße unerwünscht, wenn es für kerntechnische Zwecke, zur Herstellung von Legierungen und für Lithiumbatterien verwendet werden soll.Contaminants of any kind are extremely undesirable in lithium metal if it is to be used for nuclear purposes, for the production of alloys and for lithium batteries.

Zur Herstellung von metallischem Lithium hoher Reinheit ist es daher aus US-PS 3 962 064 bekannt, die Schmelzflußelektrolyse in einer diaphragmalosen Elektrolysezelle vorzunehmen, in der das abgeschiedene Lithiummetall auf der Elektrolytoberfläche gesammelt, durch Erhöhen des Elektrolytspiegels das Metall durch ein System von Überläufen aus der Zelle gedrückt und in ein Auffanggefäß eingeleitet wird. Das Auffanggefäß enthält eine Schutzgasatmosphäre und in dieser wird das flüssige Lithiummetall einer Reinheit von 99,9 % zu Barren vergossen. Die Nachteile der vorbekannten Vorrichtung sind in der aufwendigen apparativen Einrichtung zu sehen und darin, daß im vorbekannten Verfahren als Druckmittel für die Hebung des Elektrolytspiegels (und des Metallspiegels) Luft verwendet wird. Des weiteren wird auch das entwickelte Chlorgas mit einem großen Luftvolumen verdünnt und aus der Zelle ausgeblasen. Auf diese Weise wird von vornherein Sauerstoff bzw. Luft in nachteiliger Weise in das System eingebracht und eine nachhaltige Verunreinigung bewirkt.For the production of metallic lithium of high purity, it is therefore known from US Pat. No. 3,962,064 to carry out the melt flow electrolysis in a diaphragm-free electrolytic cell in which the deposited lithium metal is collected on the electrolyte surface, by increasing the electrolyte level, the metal through a system of overflows from the Cell is pressed and introduced into a collecting vessel. The collecting vessel contains a protective gas atmosphere and the liquid lithium metal with a purity of 99.9% is cast into bars. The disadvantages of the known device are to be seen in the complex apparatus and in the fact that in the known method air is used as a pressure medium for lifting the electrolyte level (and the metal level). Furthermore, the developed chlorine gas is diluted with a large volume of air and blown out of the cell. In this way, oxygen or air is adversely introduced into the system from the outset and causes lasting contamination.

Aus der US-A-2393685 ist eine Schmelzflußelektrolysezelle zur Herstellung von Mg bekannt, in Welcher das Metall-Salz-Schmelzgemisch in eine den Elektrodenraum umgebende Ringzone aufsteigt und von dort über ein Wehr in einem nach oben Offenen Trennraum überfließen kann.From US-A-2393685 a melt flow electrolysis cell for the production of Mg is known, in which the metal-salt melt mixture rises into an annular zone surrounding the electrode space and from there can flow over a weir in an upwardly open separation space.

Der Erfindung liegt die Aufgabe zugrunde, ein Verfahren zur Herstellung von Lithiummetall hoher Reinheit anzugeben und eine geeignete Vorrichtung zur Durchführung des Verfahrens bereitzustellen.The invention has for its object to provide a method for producing lithium metal of high purity and to provide a suitable device for performing the method.

Die Erfindung löst die Aufgabe mit einem Verfahren, wie es in Anspruch 1 dargelegt ist.The invention solves the problem with a method as set out in claim 1.

Das ausgetragene Lithiummetall wird in an sich bekannter Weise weiterbehandelt, beispielsweise zu Barren vergossen. Während der Elektrolyt in der Elektrolysezelle zirkuliert und in den Elektrodenraum rückgeführt wird, wird das anodisch abgeschiedene Chlorgas aus dem abgedeckten Gasraum über die Schmelze abgesaugt und als solches oder in Form von Salzen gewonnen. Zweckmäßig wird der Chlorgasstrom durch eine mit einer Aufschlämmung von Lithiumhydroxid beschickten Absorptionsanlage gesaugt unter Mitverwendung von Ammoniak als Reduktionsmittel gemäß:

Figure imgb0001
The lithium metal discharged is further processed in a manner known per se, for example cast into bars. While the electrolyte is being circulated in the electrolysis cell and returned to the electrode space, the anodically separated chlorine gas is sucked out of the covered gas space via the melt and obtained as such or in the form of salts. The chlorine gas stream is expediently drawn through an absorption system charged with a slurry of lithium hydroxide, with the use of ammonia as a reducing agent in accordance with:
Figure imgb0001

Das auf diese Weise gewonnene Lithiumchlorid dient wieder als Rohstoff für die Elektrolyse.The lithium chloride obtained in this way again serves as a raw material for the electrolysis.

In dem erfindungsgemäßen Verfahren ist es wesentlich, daß in der syphonartigen Rohrverbindung eine in den Trennraum gerichtete Strömung des metallhaltigen Elektrolyten geschaffen wird und daß das im Elektrodenraum aufsteigende Metall/Salzschmelze-Gemisch sofort in den Trennraum abgeführt wird. Das heißt, es soll im Elektrolysegefäß weder eine Separierung erfolgen, die durch eine zu geringe Abströmgeschwindigkeit bewirkt werden kann, noch darf eine zu hohe Strömungsgeschwindigkeiterzeugtwerden, so daß Chlorgas oder Luft in den Trennraum eingesogen wird. Das Niveau der Elektrolytschmelze kann des weiteren durch geregeltes Eintauchen eines Neutralkörpers in die Elektrolytschmelze konstant gehalten werden. In der praktischen Durchführung des erfindungsgemäßen Verfahrens verweilt das aufsteigende Metall/Salzschmelze-Gemisch etwa 2 sec. oder weniger an der Badoberfläche. Die Elektrolytströmung wird zumindest teilweise durch den « Mammutpumpeneffekt » des aufsteigenden Chlorgases bewirkt sowie des weiteren durch eine mittels mechanischer Mittel hervorgerufene Pumpwirkung im kürzeren Schenkel eines syphonartigen Verbindungsrohres zwischen Elektrolysenraum bzw. Ringraum und Trennraum erzeugt. Zur mechanischen Erzeugung der Elektrolytströmung eignen sich an sich bekannte mechanische Aggregate, wie Pumpen oder Rührer. Aus dem Trennraum wird, nach Aufbau eines Puffervolumens flüssigen und durch Seigerung gereinigten metallischen Lithiums, das Lithium kontinuierlich in eine Vorlage abgeführt und z. B. vergossen und erkalten gelassen. In dem Trennraum wird oberhalb des Schmelzenspiegels eine Schutzgasatmosphäre, beispielsweise aus Argon, aufrechterhalten.In the process according to the invention, it is essential that a flow of the metal-containing electrolyte directed into the separation space is created in the siphon-like pipe connection and that the metal / molten salt mixture rising in the electrode space is immediately discharged into the separation space. That is, there should neither be a separation in the electrolysis vessel which can be caused by an outflow velocity which is too low, nor a flow velocity which is too high, so that chlorine gas or air is drawn into the separation space. The level of the electrolyte melt can also be kept constant by controlled immersion of a neutral body in the electrolyte melt. In the practical implementation of the method according to the invention, the ascending metal / molten salt mixture remains on the bath surface for about 2 seconds or less. The electrolyte flow is at least partially caused by the “mammoth pump effect” of the rising chlorine gas and, furthermore, is generated by a pumping effect caused by mechanical means in the shorter leg of a siphon-like connecting tube between the electrolysis space or the annular space and the separation space. Mechanical units known per se, such as pumps or stirrers, are suitable for the mechanical generation of the electrolyte flow. From the Separation space is, after building up a buffer volume of liquid lithium and cleaned by segregation, the lithium continuously discharged into a template and z. B. shed and let cool. A protective gas atmosphere, for example of argon, is maintained in the separation space above the melt level.

Die Erfindung stellt des weiteren eine Elektrolysezelle zur Durchführung des Verfahrens gemäß der Erfindung bereit.The invention further provides an electrolysis cell for carrying out the method according to the invention.

Hierzu bedient sie sich einer Elektrolysezelle der eingangs genannten Artfürdie elektrolytische Gewinnung von metallischem Lithium, wobei in einem zylinderförmigen, geschlossenen Elektrolyse-Stahlbehälter eine Stahlkathode mit dem Behälterboden verschweißt ist, und die den in die Salzschmelze eintauchenden Teil einer senkrecht und gegen die Atmosphäre gasdicht angeordneten Graphitanode umgibt, sowie mit Organen zum Einführen von Lithiumchlorid, Schutzgas und zur Zufuhr elektrischer Energie und zum Austragen von Lithiummetall und Chlorgas.For this purpose, it uses an electrolysis cell of the type mentioned at the outset for the electrolytic extraction of metallic lithium, a steel cathode being welded to the bottom of the container in a cylindrical, closed electrolysis steel container, and the part of the graphite anode which is immersed in the molten salt and which is vertically and gas-tight against the atmosphere surrounds, as well as with organs for introducing lithium chloride, protective gas and for supplying electrical energy and for discharging lithium metal and chlorine gas.

In Weiterbildung einer Elektrolysezelle der genannten Art besteht die Verbesserung gemäß der Erfindung in den Merkmalen des Anspruchs 2.In a further development of an electrolytic cell of the type mentioned, the improvement according to the invention consists in the features of claim 2.

Derzylinderförmige Stahl behälter erfüllt die Aufgabe eines Trennrohres bzw. Abscheiders, d. h. in ihm trennen sich flüssiges metallisches Lithium und Elektrolytschmelze. Das Trennrohr hat daher einen kleinen Durchmesser, der etwa 1/10 des Durchmessers des Elektrolysebehälters beträgt. Dem syphonartigen Rohr, das einerseits mit der Elektrolysezelle bzw. mit der den oberen Kathodenrand umgebenden Ringwanne und andererseits mit dem Trennrohr in Verbindung steht, kommt eine wesentliche Funktion als Überströmungsrohr für das Metall/Salzschmelzen-Gemisch zu. Zur Erzeugung einer Pumpentrombe am Eingang des U-Rohres bzw. einer in das Trennrohr gerichteten Strömung ist im kürzeren Schenkel des syphonartigen Rohres ein mechanischer Förderer angeordnet. Im Sinne der Erfindung werden hierunter beispielsweise Rührwerke, wie Propellerrührer, Schneckenförderer oder Zentrifugalpumpen verstanden. Die Antriebsmittel werden durch den oberen Deckel eingeführt, durch welchen auch zweckmäßig ein Einlaß für Schutzgas geführt ist.The cylindrical steel container fulfills the task of a separating pipe or separator, d. H. liquid metallic lithium and electrolyte melt separate in it. The separating tube therefore has a small diameter which is approximately 1/10 of the diameter of the electrolysis container. The siphon-like tube, which is connected on the one hand to the electrolysis cell or to the ring trough surrounding the upper cathode edge and on the other hand to the separating tube, has an essential function as an overflow tube for the metal / molten salt mixture. A mechanical conveyor is arranged in the shorter leg of the siphon-like tube in order to generate a pump drum at the entrance of the U-tube or a flow directed into the separating tube. For the purposes of the invention, this includes, for example, agitators, such as propeller stirrers, screw conveyors or centrifugal pumps. The drive means are inserted through the upper cover, through which an inlet for protective gas is also expediently guided.

Im allgemeinen ist es für ein rasches Abziehen des Metall/Salzschmelze-Gemisches aus der Auffangrinne (4) nach unten ausreichend, daß das syphonartige Rohr (15) auf seiner gesamten Länge, d. h. im längeren und kürzeren Schenkel, den gleichen Durchmesser aufweist. Nach einer weiteren Ausgestaltung der Erfindung weist der längere Schenkel (16a) bzw. das Ansaugrohr einen kleineren Durchmesser als der kürzere Schenkel auf. Gemäß dieser Ausführungsform der Erfindung ist der obere Abschnitt des kürzeren Schenkels zu einem zylindrischen Teil größeren Durchmessers (16) erweitert. Im allgemeinen beträgt das Verhältnis von kleinerem zu größerem Durchmesser 1 : 2 bis 1 : 12 und vorzugsweise 1 : 5 bis 1 : 10.In general, for a rapid withdrawal of the metal / molten salt mixture from the gutter (4) downwards, it is sufficient that the siphon-like tube (15) over its entire length, i. H. in the longer and shorter leg, has the same diameter. According to a further embodiment of the invention, the longer leg (16a) or the suction pipe has a smaller diameter than the shorter leg. According to this embodiment of the invention, the upper section of the shorter leg is expanded into a cylindrical part of larger diameter (16). In general, the ratio of smaller to larger diameter is 1: 2 to 1:12 and preferably 1: 5 to 1:10.

Die Graphitanode wird durch den Deckel in das Elektrolysegefäß eingeführt. Sie kann an dem Deckel befestigt werden und hängend in den Kathodenraum hineinragen. Zweckmäßig wird sie jedoch isolierend und leicht auswechselbar durch den Deckel hindurchgeführt und sitzt dann überein elektrisch isolierendes Formteil auf dem eisernen Behälterboden auf. Ein solches isolierendes Formteil besteht zweckmäßigerweise aus oxidkeramischem Material, beispielsweise aus geschmolzenem Aluminiumoxid. Zweckmäßig wird während des Zellenbetriebes das isolierende Formteil gegen den korrosiven Angriff des schmelzflüssigen Elektrolyten durch partiell erstarrte Salzschmelze geschützt. Dies wird durch geeignete Temperaturführung bewirkt.The graphite anode is inserted through the lid into the electrolysis vessel. It can be attached to the lid and protrude hanging into the cathode compartment. However, it is expediently passed through the lid in an insulating and easily replaceable manner and then sits on the iron container bottom via an electrically insulating molded part. Such an insulating molded part advantageously consists of oxide-ceramic material, for example of molten aluminum oxide. The insulating molded part is expediently protected against the corrosive attack of the molten electrolyte by partially solidified molten salt during cell operation. This is achieved by suitable temperature control.

Die Graphitanode kann als massive Platte oder Massivzylinder ausgebildet sein. Dementsprechend ist auch die Ausbildung der Kathode als kastenförmige Hohlkathode oder als Hohlzylinder vorgesehen. Kathode und Zelle liegen auf gemeinsamem potential. Der negative Pol der Spannungsquelle ist mit dem Zellenboden verbunden.The graphite anode can be designed as a solid plate or solid cylinder. Accordingly, the cathode is also designed as a box-shaped hollow cathode or as a hollow cylinder. The cathode and cell share the same potential. The negative pole of the voltage source is connected to the cell bottom.

Der obere Rand der Kathode ragt im praktischen Betrieb der Elektrolysezelle über den Spiegel des schmelzflüssigen Elektrolyten hinaus. Um den äußeren Rand der Kathode ist eine ringförmige Auffangrinne angebracht, die den aufsteigenden, Lithiummetall enthaltenden Elektrolyten aufnimmt und ihn unmittelbar über eine Öffnung im Boden der Auffangrinne in den langen Schenkel des syphonartigen Rohres fördert. Als Förderkraft dient zunächst der Mammutpumpeneffekt ? » des aufsteigenden Chlorgases. Zwecks besseren Überlaufs des metallhaltigen Salzschmelzengemisches ist der obere Kathodenrand, wie bei Überlaufrändern üblich, zahnkranzförmig ausgebildet. Die Erfindung wird anhand eines Beispiels und der Zeichnung näher und beispielhaft erläutert.In practical operation of the electrolysis cell, the upper edge of the cathode protrudes beyond the level of the molten electrolyte. Around the outer edge of the cathode there is an annular collecting trough which receives the ascending electrolyte containing lithium metal and conveys it directly through an opening in the bottom of the collecting trough into the long leg of the siphon-like tube. The mammoth pump effect serves as the conveying force? »Of the rising chlorine gas. In order to improve the overflow of the metal-containing molten salt mixture, the upper edge of the cathode, as is customary with overflow edges, is in the form of a ring gear. The invention is explained in more detail and by way of example using an example and the drawing.

Die Figur der Abbildung zeigt eine erfindungsgemäße Vorrichtung. wThe figure in the figure shows a device according to the invention. w

In der mit Deckel 2 verschlossenen Elektrolysezelle 1 ist die Kathode 3 angeordnet und mit dem Gefäßboden verschweißt. Der obere Rand der Kathode 3 ist mit einer Auffangrinne 4 für die überfließende Lithiummetall enthaltende Salzschmelze versehen. Durch den Deckel 2 ist die Graphitanode 5 eingeführt, die über den Isolierkörper 6 auf dem Boden der Elektrolysezelle 1 aufsitzt und von der Kathode 3 umgeben ist. Der positive Pol einer Gleichspannungsenergiequelle ist bei 7 und der negative Pol bei 8 angeschlossen. Über die Öffnungen 9 im unteren Teil der Kathodenwand wird die Zirkulation des schmelzflüssigen Elektrolyten ermöglicht. Durch das Rohr 10 wird entsprechend dem Verbrauch Lithiumchlorid in das Salzschmelzengemisch nachchargiert. Entwickeltes Chlorgas entweicht durch den Auslaß 11. In der Elektrolysezelle ist weiterhin ein mit Deckel 13 verschlossenes Trennrohr 12 angeordnet. Das Trennrohr 12 ist in den Deckel 2 der Elektrolysezelle 1 eingeschweißt, überragt die Zelle und führt bis zum Boden der Zelle 1. Im unteren Teil des Trennrohres 12 ermöglichen Öffnungen 14 den Ausgleich der Salzschmelze mit dem übrigen schmelzflüssigen Elektrolyten. Das Trennrohr 12 steht über das syphonartige Verbindungsrohr 15 mit der Auffangrinne 4 in Verbindung. Das U-förmige Verbindungsrohr 15 ist mit seinem längeren Schenkel in den Boden der Auffangrinne 4 eingeführt, während die Öffnung des kürzeren Schenkels zu einem größeren Rohrdurchmesser 16 erweitert ist. In dem Rohrteil 16 ist ein Rührer 17 angeordnet, dessen Welle durch den Deckel 13 des Trennrohres 12 eingeführt ist. Im Deckel 13 ist ferner ein Einlaß für Schutzgas angebracht. Das schmelzflüssige Lithiummetall wird über das Rohr 19 aus dem Trennrohr ausgetragen. Das isolierende Formstück 6 ist durch erstarrte Schmelze 20 gegen korrosiven Angriff der Schmelze geschützt.The cathode 3 is arranged in the electrolysis cell 1 closed by cover 2 and welded to the bottom of the vessel. The upper edge of the cathode 3 is provided with a collecting channel 4 for the molten salt metal which overflows. The graphite anode 5 is inserted through the cover 2 and is seated on the bottom of the electrolytic cell 1 via the insulating body 6 and is surrounded by the cathode 3. The positive pole of a DC power source is connected at 7 and the negative pole at 8. The circulation of the molten electrolyte is made possible via the openings 9 in the lower part of the cathode wall. Through the pipe 10, lithium chloride is added to the molten salt mixture in accordance with the consumption charged. Developed chlorine gas escapes through the outlet 11. In the electrolysis cell, a separating tube 12, which is closed with a lid 13, is also arranged. The separating tube 12 is welded into the cover 2 of the electrolytic cell 1, protrudes above the cell and leads to the bottom of the cell 1. In the lower part of the separating tube 12, openings 14 enable the molten salt to be balanced with the other molten electrolyte. The separating pipe 12 is connected to the gutter 4 via the siphon-like connecting pipe 15. The U-shaped connecting pipe 15 is inserted with its longer leg into the bottom of the gutter 4, while the opening of the shorter leg is widened to a larger pipe diameter 16. A stirrer 17 is arranged in the tube part 16, the shaft of which is inserted through the cover 13 of the separating tube 12. In the cover 13, an inlet for protective gas is also attached. The molten lithium metal is discharged from the separating tube via the tube 19. The insulating shaped piece 6 is protected against corrosive attack by the melt by solidified melt 20.

In dem erfindungsgemäßen Verfahren dient als Elektrolyt ein eutektisches Salzgemisch aus ca. 50 Gew.-% Lithiumchlorid und ca. 50 Gew.-% Kaliumchlorid. Die Betriebstemperatur beträgt 400 °C. Die Stromdichte liegt bei 5 000 bis 10 000 Amp./m2 vorzugsweise 6 000 Amp./m2. Die Zellenspannung betragt dementsprechend 6,2 bis 9,2 Volt. Die Stromausbeute liegt bei über 90 %. Als Werkstoff für Zelle und Kathode wird normaler Konstruktionsstahl verwendet. Die Wandstärke der Zelle beträgt etwa 20 mm, die Zelle besitzt keine keramische Auskleidung. Die Anode aus Elektrographit ist zentrisch in den Kathodenraum eingesetzt. Der Elektrodenabstand beträgt etwa 50 mm. Bei Behieb der Zelle sammelt sich das anodisch abgeschiedene Chlor im Gasraum über der Salzschmelze und wird bei geringem Unterdruck aus der Zelle entfernt. Das aus dem Elektrodenraum aufsteigende, Lithiummetall enthaltende Salzschmelzengemisch läuft in die Auffangrinne über. Das bereits dort teilweise aufschwimmende Lithiummetall wird sofort mit sehr viel Schmelze mit hoher Strömungsgeschwindigkeit zum Einlauf des syphonartigen Rohres gefördert. Die hohe Strömungsgeschwindigkeit im U-Rohr wird durch ein Flügelrührwerk erzeugt. Im Trennrohr scheidet sich das metallische Lithium unter Argonatmosphäre aus dem Lithiummetall enthaltenden Salzschmelzengemisch ab und schwimmt auf, während das Salzschmelzengemisch das Trennrohr in abwärts gerichteter Strömung verläßt und in den Kreislauf zurückkehrt. Das gesammelte schmelzflüssige Lithiummetall reinigt sich durch Seigerung von weiteren Verunreinigungen und wird kontinuierlich oder diskontinuierlich ausgetragen und unter geeigneten Bedingungen, wie unter Schutzgasatmosphäre oder im Vakuum, in an sich bekannterweise weiterverarbeitet. Das nach dem erfindungsgemäßen Verfahren gewonnene Lithiummetall hoher Reinheit hat folgende Analyse :

Figure imgb0002
In the process according to the invention, a eutectic salt mixture of approximately 50% by weight lithium chloride and approximately 50% by weight potassium chloride serves as the electrolyte. The operating temperature is 400 ° C. The current density is 5,000 to 10,000 amps / m 2, preferably 6,000 amps / m 2 . The cell voltage is accordingly 6.2 to 9.2 volts. The current yield is over 90%. Normal structural steel is used as the material for the cell and cathode. The wall thickness of the cell is about 20 mm, the cell has no ceramic lining. The anode made of electrographite is inserted centrally in the cathode compartment. The distance between the electrodes is about 50 mm. When the cell is operated, the anodically separated chlorine collects in the gas space above the molten salt and is removed from the cell at a low vacuum. The molten salt mixture containing lithium metal rising from the electrode space runs into the collecting trough. The lithium metal, which is already partially floating there, is immediately conveyed to the inlet of the siphon-like pipe with a great deal of melt at high flow speed. The high flow velocity in the U-tube is generated by a paddle mixer. In the separating tube, the metallic lithium separates from the molten salt mixture containing lithium metal under an argon atmosphere and floats, while the molten salt mixture leaves the separating tube in a downward flow and returns to the circuit. The molten lithium metal collected cleans itself of further impurities by segregation and is discharged continuously or discontinuously and, in a manner known per se, processed further under suitable conditions, such as under a protective gas atmosphere or in vacuo. The high purity lithium metal obtained by the process according to the invention has the following analysis:
Figure imgb0002

Die Vorteile des erfindungsgemäßen Verfahrens sind darin zu sehen, daß in kontinuierlichem Betrieb metallisches Lithium hoher Reinheit in wirtschaftlicher Weise in einer Vorrichtung einfacher und technisch nicht aufwendiger Konstruktion gewonnen wird.The advantages of the process according to the invention can be seen in the fact that metallic lithium of high purity is obtained economically in a device of simple and technically not complex construction in continuous operation.

Claims (8)

1. Method for obtaining high-purity metallic lithium by electrolysis of a mixture of molten materials comprising lithium chloride and potassium chloride in a diaphragm-less electrolytic cell, removal of the molten lithium, transfer into a receiver and cooling, characterised in that the mixture of molten materials containing metallic lithium which rises in the inter-electrode space is collected in an annular zone surrounding the upper end of the cathode in the region of the surface level of the molten material and is removed therefrom via a siphon-type pipe connection into a separating chamber which communicates with the electrolytic cell and is sealed off against the chlorine gas atmosphere thereof, with a flow of the mixture of molten materials containing lithium metal which is directed into the separating chamber being produced in the siphon-type pipe connection by means of a mechanical conveying means and the electrolyte and the lithium metal being separated in the separating chamber under a protective gas atmosphere and the lithium metal being discharged into a receiver under a protective gas atmosphere with recycling of the electrolyte.
2. Electrolytic cell for performing the method according to Claim 1 for obtaining metallic lithium by electrolysis, wherein in a closed cylindrical, steel electrolysis tank a steel cathode is welded to the base of the tank, which cathode surrounds that part of a graphite anode which is arranged vertically and so as to be gas-tight against the atmosphere and which dips into the molten salt mixture, and also with elements for introducing lithium chloride, protective gas and for the supply of electric power and for discharging lithium metal and chlorine gas, characterised in that a steel cylinder which is closed at the top is eccentrically disposed in the steel electrolysis tank, which cylinder projects above the electrolysis tank and rests on the base of the vessel, and into the lower part of the cylindrical wall of which a substantially U-shaped tube is welded, the shorter arm of which opens centrally into the separation column, with a mechanical conveying means being located in the shorter arm of the U-tube, and the longer arm of which opens into an annular trough which surrounds the upper end of the steel cathode, and the cylindrical shell having apertures in its lower part.
3. Electrolytic cell according to Claim 2, characterised in that the longer arm of the U-tube has a smaller diameter than the upper section of the shorter arm.
4. Electrolytic cell according to Claims 2 and 3, characterised in that the ratio of the smaller to the larger diameter is 1 : 2 to 1 : 12 and preferably 1 : 5 to 1 : 10.
5. Electrolytic cell according to Claims 2 to 4, characterised in that the cylindrical shell has an outlet member for liquid lithium metal.
6. Electrolytic cell according to Claims 2 to 5, characterised in that the steel cylinder has an inlet member for protective gas.
7. Electrolytic cell according to Claims 2 to 6, characterised in that the graphite anode is seated on the bottom of the tank by means of an electrically insulating formed part.
8. Electrolytic cell according to Claims 2 to 7, characterised in that the graphite anode is constructed as a solid cylinder or a solid plate.
EP86201529A 1985-09-14 1986-09-05 Process and apparatus for manufacturing very pure lithium by molten salt electrolysis Expired - Lifetime EP0217438B2 (en)

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Families Citing this family (33)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2216898B (en) * 1988-03-29 1992-01-02 Metallurg Inc Transporting a liquid past a barrier
US4882017A (en) * 1988-06-20 1989-11-21 Aluminum Company Of America Method and apparatus for making light metal-alkali metal master alloy using alkali metal-containing scrap
US4973390A (en) * 1988-07-11 1990-11-27 Aluminum Company Of America Process and apparatus for producing lithium from aluminum-lithium alloy scrap in a three-layered lithium transport cell
US4988417A (en) * 1988-12-29 1991-01-29 Aluminum Company Of America Production of lithium by direct electrolysis of lithium carbonate
US5417815A (en) * 1994-02-07 1995-05-23 Martin Marietta Energy Systems, Inc. Liquid surface skimmer apparatus for molten lithium and method
JP3812951B2 (en) * 1995-04-21 2006-08-23 アルキャン・インターナショナル・リミテッド Multipolar electrolyzer for metal recovery by electrolysis of molten electrolyte
US5660710A (en) * 1996-01-31 1997-08-26 Sivilotti; Olivo Method and apparatus for electrolyzing light metals
US5855757A (en) * 1997-01-21 1999-01-05 Sivilotti; Olivo Method and apparatus for electrolysing light metals
US6056803A (en) * 1997-12-24 2000-05-02 Alcan International Limited Injector for gas treatment of molten metals
RU2135615C1 (en) * 1997-12-25 1999-08-27 Открытое акционерное общество "Новосибирский завод химконцентратов" Method of lithium production
US6497807B1 (en) 1998-02-11 2002-12-24 Northwest Aluminum Technologies Electrolyte treatment for aluminum reduction
IL140563A (en) 1998-07-08 2004-09-27 Alcan Int Ltd Molten salt electrolytic cell having metal reservoir
DE19859563B4 (en) * 1998-12-22 2008-01-24 Basf Ag Improved process for the electrochemical production of alkali metal from alkali metal amalgam
US6436272B1 (en) 1999-02-09 2002-08-20 Northwest Aluminum Technologies Low temperature aluminum reduction cell using hollow cathode
US6787019B2 (en) * 2001-11-21 2004-09-07 E. I. Du Pont De Nemours And Company Low temperature alkali metal electrolysis
JP2009019250A (en) * 2007-07-13 2009-01-29 Osaka Titanium Technologies Co Ltd Method and apparatus for producing metal
CN101469373B (en) * 2007-12-28 2011-05-11 中国蓝星（集团）股份有限公司 Lithium production device
DE102008031437A1 (en) * 2008-07-04 2010-01-07 Siemens Aktiengesellschaft Mobile energy source and energy storage
JP5470332B2 (en) * 2010-06-24 2014-04-16 アイ’エムセップ株式会社 Ammonia electrosynthesis method and ammonia electrosynthesis apparatus
CN101962782A (en) * 2010-08-11 2011-02-02 华东理工大学 Method for removing Al impurity from KCl-LiCl lithium electrolyte
CN102002730A (en) * 2010-12-08 2011-04-06 华东理工大学 A method for removing impurity MgCl2 in lithium electrolyte KCl-LiCl
WO2016040244A2 (en) 2014-09-09 2016-03-17 JALBOUT, Abraham, Fouad A system, apparatus, and process for leaching metal and storing thermal energy during metal extraction
JP6610089B2 (en) * 2014-10-03 2019-11-27 Ｔｄｋ株式会社 Stabilized lithium powder and lithium ion secondary battery using the same
US9499880B2 (en) 2015-03-06 2016-11-22 Battelle Memorial Institute System and process for production of magnesium metal and magnesium hydride from magnesium-containing salts and brines
CN107574458B (en) * 2017-09-20 2024-03-29 宜春赣锋锂业有限公司 Metal lithium electrolytic tank for collecting lithium intensively
CN112011803A (en) * 2020-05-19 2020-12-01 金昆仑锂业有限公司 Fused salt electrolytic cell with lithium collecting chamber
RU2741723C2 (en) * 2020-06-09 2021-01-28 Общество с ограниченной ответственностью "Экостар-Наутех" Method for producing lithium metal and installation for its implementation
AU2022211401A1 (en) * 2021-01-21 2023-08-10 Li-Metal Corp. Process for production refined lithium metal
CA3183180A1 (en) * 2021-01-21 2022-07-28 Maciej Jastrzebski Electrorefining apparatus and process for refining lithium metal
KR20230131926A (en) 2021-01-21 2023-09-14 리-메탈 코포레이션 Electrowinning cell and method of using same for production of metal products
EP4463580A4 (en) * 2022-01-13 2026-03-25 Hydro Quebec DEVICE AND METHOD FOR THE PRODUCTION OF LI-METAL
US11976375B1 (en) 2022-11-11 2024-05-07 Li-Metal Corp. Fracture resistant mounting for ceramic piping
KR102879381B1 (en) * 2023-06-20 2025-10-31 (주)하나기술 Continuous manufacturing apparatus of lithium metal ingot

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2862863A (en) * 1957-09-23 1958-12-02 Kenneth F Griffith Apparatus for electrolytic production of a metal product from fused salts
US3396094A (en) * 1962-10-25 1968-08-06 Canada Aluminum Co Electrolytic method and apparatus for production of magnesium
FR2243277B1 (en) * 1973-09-07 1976-06-18 Commissariat Energie Atomique
IS1214B6 (en) * 1981-02-26 1986-04-02 Alcan International Limited Electrotechnical to produce metal
IS1264B6 (en) * 1982-06-14 1987-03-27 Alcan International Limited Metallurgy with electrolysis of molten electrolyte (ionized solution)
FR2560221B1 (en) * 1984-02-24 1989-09-08 Rhone Poulenc Spec Chim PROCESS AND DEVICE FOR THE CONTINUOUS MANUFACTURE OF LITHIUM
FR2532332B1 (en) * 1982-08-31 1986-04-04 Rhone Poulenc Spec Chim PROCESS FOR THE CONTINUOUS PREPARATION OF LITHIUM BY ELECTROLYSIS OF LITHIUM CHLORIDE IN A MIXTURE OF MOLTEN SALTS AND APPARATUS FOR CARRYING OUT SAID PROCESS

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