WO2022211128A1 - リチウム化合物の製造方法及びリチウム化合物の製造装置 - Google Patents

リチウム化合物の製造方法及びリチウム化合物の製造装置 Download PDF

Info

Publication number
WO2022211128A1
WO2022211128A1 PCT/JP2022/017005 JP2022017005W WO2022211128A1 WO 2022211128 A1 WO2022211128 A1 WO 2022211128A1 JP 2022017005 W JP2022017005 W JP 2022017005W WO 2022211128 A1 WO2022211128 A1 WO 2022211128A1
Authority
WO
WIPO (PCT)
Prior art keywords
lithium
organic acid
aqueous solution
hydroxide
liquid
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/JP2022/017005
Other languages
English (en)
French (fr)
Japanese (ja)
Inventor
秀樹 山本
太 宇都野
大輔 森
弘幸 樋口
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.)
Idemitsu Kosan Co Ltd
Original Assignee
Idemitsu Kosan Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Idemitsu Kosan Co Ltd filed Critical Idemitsu Kosan Co Ltd
Priority to US18/553,099 priority Critical patent/US20240182316A1/en
Priority to CN202280025918.4A priority patent/CN117098728A/zh
Priority to JP2023511762A priority patent/JP7781147B2/ja
Publication of WO2022211128A1 publication Critical patent/WO2022211128A1/ja
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
    • C01D15/00—Lithium compounds
    • C01D15/02—Oxides; Hydroxides
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
    • B01D61/42—Electrodialysis; Electro-osmosis ; Electro-ultrafiltration; Membrane capacitive deionization
    • B01D61/44—Ion-selective electrodialysis
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D9/00—Crystallisation
    • B01D9/0018—Evaporation of components of the mixture to be separated
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J19/24—Stationary reactors without moving elements inside
    • B01J19/245—Stationary reactors without moving elements inside placed in series
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
    • C01D15/00—Lithium compounds
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
    • C01D15/00—Lithium compounds
    • C01D15/08—Carbonates; Bicarbonates
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
    • C25B15/00—Operating or servicing cells
    • C25B15/08—Supplying or removing reactants or electrolytes; Regeneration of electrolytes
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
    • C25B3/00—Electrolytic production of organic compounds
    • C25B3/01—Products
    • C25B3/07—Oxygen containing compounds
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
    • C25B9/00—Cells or assemblies of cells; Constructional parts of cells; Assemblies of constructional parts, e.g. electrode-diaphragm assemblies; Process-related cell features
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D9/00—Crystallisation
    • B01D2009/0086—Processes or apparatus therefor
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D9/00—Crystallisation
    • B01D9/0004—Crystallisation cooling by heat exchange
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D9/00—Crystallisation
    • B01D9/0018—Evaporation of components of the mixture to be separated
    • B01D9/0022—Evaporation of components of the mixture to be separated by reducing pressure
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D9/00—Crystallisation
    • B01D9/0018—Evaporation of components of the mixture to be separated
    • B01D9/0031—Evaporation of components of the mixture to be separated by heating
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D9/00—Crystallisation
    • B01D9/0036—Crystallisation on to a bed of product crystals; Seeding
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D9/00—Crystallisation
    • B01D9/005—Selection of auxiliary, e.g. for control of crystallisation nuclei, of crystal growth, of adherence to walls; Arrangements for introduction thereof
    • B01D9/0054—Use of anti-solvent
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D9/00—Crystallisation
    • B01D9/0059—General arrangements of crystallisation plant, e.g. flow sheets

Definitions

  • the present invention relates to a lithium compound manufacturing method and a lithium compound manufacturing apparatus.
  • Batteries used for such applications have conventionally used electrolytes containing flammable organic solvents. Batteries in which the electrolyte is replaced with a solid electrolyte layer are being developed because the safety device can be simplified and the manufacturing cost and productivity are excellent.
  • Lithium secondary batteries and the like are used as batteries for the above-mentioned applications, and in recent years, their use in hybrid cars and electric vehicles, which are being developed to comply with carbon dioxide emission regulations, is being considered. ing.
  • Sulfide solid electrolytes are known as solid electrolytes used in lithium secondary batteries and the like.
  • a sulfide solid electrolyte has high ionic conductivity, and is therefore useful for increasing the output of a battery.
  • Lithium sulfide is widely used as a raw material in the production of sulfide solid electrolytes, and as the demand for lithium sulfide increases, the demand for lithium hydroxide as a raw material is increasing.
  • the method for producing lithium hydroxide there is a method of electrolyzing an aqueous solution or suspension of lithium carbonate to generate an aqueous solution of lithium hydroxide through an ion exchange membrane (see, for example, Patent Document 1). Also, the method for producing lithium hydroxide includes a step of reacting lithium carbonate with an acid containing acetic acid to produce lithium acetate, and a step of producing lithium hydroxide by reacting lithium acetate with a metal hydroxide. A method has been proposed (see, for example, Patent Document 2).
  • Non-Patent Documents 1 and 2 a technique for recovering lithium from brackish water of a salt lake using a manganese oxide compound as an adsorbent
  • a technique for recovering lithium by solar evaporation of brackish water for example, , Non-Patent Documents 1 and 3
  • Non-Patent Documents 1 to 3 While the demand for lithium used in solid electrolytes is expected to expand, in order to seek a wider range of lithium sources, it is possible to obtain from a wide range of aqueous solutions such as brackish water and geothermal water as disclosed in Non-Patent Documents 1 to 3. , it is necessary to deal with low-grade lithium sources containing impurities.
  • Patent Document 1 and the like there is a problem that if a low-grade lithium source is used, electrolysis using an ion-exchange membrane needs to consume a large amount of energy. Solving these problems is extremely important in the process of meeting the growing demand for lithium and promoting industrialization. Similarly, it is also extremely important to improve the production efficiency of the lithium compound in the method described in Patent Document 2.
  • the present invention has been made in view of such circumstances, and a method for producing a lithium compound and a lithium compound that can efficiently produce a high-purity lithium compound from low-grade lithium carbonate containing impurities such as brine.
  • the purpose is to provide a manufacturing apparatus for
  • the method for producing a lithium compound according to the present invention comprises: mixing lithium carbonate, an acid containing an organic acid, and water in a reaction vessel 1 to produce an aqueous lithium organic acid solution containing lithium organic acid;
  • the organic acid lithium aqueous solution and the metal hydroxide are mixed in the reaction vessel 2 to generate the lithium hydroxide aqueous solution, and the organic acid metal by-produced by the generation of the lithium hydroxide aqueous solution is subjected to electrochemical reaction. returning the organic acid regenerated using the apparatus to the reaction vessel 1 and using it as the organic acid;
  • a method for producing a lithium compound comprising is.
  • the apparatus for producing a lithium compound according to the present invention includes: Equipped with a reaction vessel 1, a reaction vessel 2, an electrochemical device and a return pipe,
  • the reaction tank 1 is a tank for mixing lithium carbonate, an acid containing an organic acid, and water to produce an aqueous lithium organic acid solution
  • the reaction tank 2 is a tank for mixing the aqueous lithium organic acid solution and the metal hydroxide to produce an aqueous lithium hydroxide solution
  • the electrochemical device is a device for regenerating the organic acid used in generating the aqueous lithium organic acid solution from an aqueous solution obtained by removing lithium hydroxide from the aqueous lithium hydroxide solution
  • the return pipe is a pipe for returning the regenerated organic acid to the reaction vessel 1, Lithium compound manufacturing equipment, is.
  • the present invention it is possible to provide a lithium compound manufacturing method and a lithium compound manufacturing apparatus capable of efficiently manufacturing a high-purity lithium compound from low-grade lithium carbonate containing impurities such as brine.
  • FIG. 1 is a flow diagram showing a preferred aspect of a lithium compound production apparatus capable of performing the lithium compound production method of the present embodiment.
  • FIG. 1 is a flow diagram showing a preferred aspect of a lithium compound production apparatus capable of performing the lithium compound production method of the present embodiment.
  • BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a flow diagram showing a preferred aspect of a lithium compound production apparatus capable of performing the lithium compound production method of the present embodiment.
  • BRIEF DESCRIPTION OF THE DRAWINGS is a flow diagram showing a preferred aspect of a lithium compound production apparatus capable of performing the lithium compound production method of the present embodiment.
  • FIG. 1 is a flow diagram showing a preferred aspect of a lithium compound production apparatus capable of performing the lithium compound production method of the present embodiment.
  • 1 is a schematic diagram showing a preferred embodiment of an electrochemical device; FIG.
  • this embodiment A method for producing a lithium compound and an apparatus for producing a lithium compound according to one embodiment of the present invention (hereinafter referred to as "this embodiment") will be described below. It should be noted that the method for producing a lithium compound and the apparatus for producing a lithium compound according to one embodiment of the present invention are merely one embodiment of the method for producing a lithium compound and the apparatus for producing a lithium compound according to one embodiment of the present invention. It is not limited to the method for producing a lithium compound and the apparatus for producing a lithium compound of one embodiment. In addition, in this specification, lithium means both lithium and lithium ions, and shall be interpreted appropriately as long as there is no technical contradiction.
  • the upper and lower limits of the numerical ranges of "more than”, “less than”, and “to” are values that can be arbitrarily combined, and the values in the examples can also be used as the upper and lower limits. can.
  • a numerical range is described as “A to B” and “C to D”
  • numerical ranges such as “A to D” and “C to B” are also included. The same applies to the terms “above” and “below”.
  • Patent Document 1 there has conventionally been a method for producing a lithium hydroxide aqueous solution from an aqueous lithium carbonate solution or the like using an electrochemical device using an ion-exchange resin.
  • this method can remove anions such as carbonate ions and sulfate ions using an ion exchange resin, it does not have high selectivity for metal ions.
  • a pretreatment step is required to remove it immediately.
  • the present inventors have proposed a reaction in which lithium carbonate, an organic acid such as acetic acid, and water are mixed to form an organic lithium oxide, and an aqueous solution of an organic acid lithium is mixed with a metal hydroxide to form lithium hydroxide.
  • a reaction of producing lithium hydroxide attention can also be paid to the reaction of producing lithium hydroxide by, for example, mixing lithium carbonate and calcium hydroxide.
  • the reactivity between lithium carbonate and calcium hydroxide is not high, and heating is required to promote the reaction.
  • due to the relationship with calcium hydroxide it takes time to dissolve lithium carbonate, and it is necessary to use a large amount of water.
  • the solubility of lithium carbonate is improved by adopting the reaction using an organic acid such as acetic acid
  • the amount of water used can be reduced. Reducing the amount of water used leads to increased efficiency of the manufacturing process as a whole.
  • the reaction using an organic acid such as acetic acid is highly reactive and does not require heating to promote the reaction, which is more advantageous than the reaction between lithium carbonate and calcium hydroxide.
  • the lithium hydroxide is produced by mixing the lithium organic acid and the metal oxide, and the aqueous solution after recovering the lithium hydroxide contains the organic acid metal. can be reused for the reaction with lithium carbonate.
  • an electrochemical device In regenerating organic acids from organic acid metals, we considered adopting an electrochemical device.
  • An electrochemical device using an ion exchange membrane is also employed in the method of Patent Document 1.
  • Patent Document 1 when lithium hydroxide is converted from lithium carbonate using an electrochemical device, if low-grade lithium carbonate is used as a raw material, the concentration of lithium carbonate is low. A lot of energy is required. In this regard, in the present invention, the content of the organic acid metal is high, so energy consumption can be reduced.
  • the energy consumption required for heating and depressurization and the energy consumption in the electrochemical device can be reduced, and the amount of water used can also be reduced. Therefore, it is considered possible to efficiently produce a high-purity lithium compound from low-grade lithium carbonate containing metals other than lithium as impurities, such as brine.
  • the present inventors have arrived at the present invention based on the above findings.
  • a method for producing a lithium compound according to the first form of the present embodiment includes: mixing lithium carbonate, an acid containing an organic acid, and water in a reaction vessel 1 to produce an aqueous lithium organic acid solution containing lithium organic acid;
  • the organic acid lithium aqueous solution and the metal hydroxide are mixed in the reaction vessel 2 to generate the lithium hydroxide aqueous solution, and the organic acid metal by-produced by the generation of the lithium hydroxide aqueous solution is subjected to electrochemical reaction. returning the organic acid regenerated using the apparatus to the reaction vessel 1 and using it as the organic acid;
  • a method for producing a lithium compound comprising is.
  • the invention according to the method for producing a lithium compound of the present embodiment produces a lithium organic acid by two reactions, that is, mixing lithium carbonate, an acid containing an organic acid such as acetic acid, and water. This is done by paying attention to the reaction to produce lithium hydroxide by the reaction and the mixing of the aqueous solution of lithium organic acid and the metal hydroxide.
  • An aqueous solution of an organic acid such as acetic acid has high solubility with lithium carbonate and high reactivity, so that the reaction proceeds rapidly without heating. Further, since the aqueous solution of organic acid lithium obtained by the reaction has high reactivity with the metal hydroxide, lithium hydroxide can be easily generated. Further, in these reactions, since the solubility of lithium carbonate is high, the amount of water used in forming an aqueous solution can be reduced, and the efficiency of the production method as a whole is improved.
  • the reaction for producing lithium hydroxide is performed, and the aqueous solution after recovering the lithium hydroxide contains the organic acid metal.
  • An aqueous solution containing this organic acid metal can be used in an electrochemical device, specifically by supplying it as a catholyte to the electrochemical device, so that an organic acid such as acetic acid can be regenerated. It will be used for reaction with lithium.
  • the aqueous solution obtained by regenerating the organic acid from the aqueous solution containing the organic acid metal contains the metal hydroxide, the aqueous solution containing the metal hydroxide reacts by mixing with the organic acid lithium.
  • the device consumes energy.
  • the content of the organic acid metal in the aqueous solution containing the organic acid metal to be supplied to the electrochemical device is high, the energy consumption required for recovering the organic acid such as acetic acid from the aqueous solution is low, for example, low-grade lithium carbonate. can be kept lower than in the case of producing lithium hydroxide from an electrochemical device. Therefore, energy consumption in the electrochemical device can also be reduced.
  • the consumption of energy required for heating and the like is reduced by adopting a highly reactive reaction.
  • the amount of water used can be reduced.
  • an electrochemical device it is possible to reuse the solution and reduce waste as much as possible by realizing recycling via organic acids such as acetic acid while reducing energy consumption.
  • a method for producing a lithium compound according to a second aspect of the present embodiment includes, in the first aspect, The metal hydroxide is regenerated by the electrochemical device and returned to the reaction vessel 2, That's what it means.
  • the metal hydroxide regenerated by the electrochemical device is intended to be used for the reaction with the lithium organic oxide.
  • an organic acid such as acetic acid obtained by regenerating with an electrochemical device is used in the reaction by mixing with lithium carbonate to reduce waste, but acetic acid, etc.
  • method 1 is performed by recovering only lithium ions using a lithium ion separator equipped with a Li selective permeable membrane, which will be described later. (hereinafter sometimes simply referred to as "Method 1"), and Method 2 (hereinafter sometimes simply referred to as "Method 2”) obtained through crystallization, solid-liquid separation, re-dissolution, and impurity removal. is mentioned. From the viewpoint of obtaining high-purity lithium hydroxide more efficiently, a method of recovering only lithium ions using a lithium ion separation device equipped with a Li permselective membrane is preferable.
  • a method by filtration, a method by heat concentration, a method by pH crystallization, etc. can be adopted for crystallization.
  • a method by crystallization is preferred.
  • a chemical such as potassium hydroxide may be used, and thus an increase in the amount of chemical used is a problem.
  • the method of recovering only lithium ions using a lithium ion separator equipped with a Li selective permeable membrane in Method 1 there is no need to use chemicals, and high-purity lithium hydroxide can be obtained. have an advantage.
  • the recovered liquid in which only lithium ions are recovered in the lithium ion separator is subjected to crystallization such as cooling crystallization, evaporation crystallization, etc., and solid-liquid High-purity lithium hydroxide can be obtained by performing the separation. Therefore, according to method 1, when obtaining high-purity lithium hydroxide, in addition to crystallization and solid-liquid separation, it is necessary to further perform re-dissolution, impurity removal, etc., compared to method 2. There is also an advantage in that pure lithium hydroxide can be obtained.
  • a method for producing a lithium compound according to the fourth aspect of the present embodiment, in the third aspect Furthermore, crystallizing the recovered liquid recovered using the lithium ion separator and performing solid-liquid separation 1, That's what it means. As a result, high-purity lithium hydroxide can be obtained while reducing the amount of chemicals used.
  • “high purity” and “high purity” mean 99% or more in terms of crystal purity.
  • a method for producing a lithium compound according to the fifth aspect of the present embodiment, in the third or fourth aspect, With the Li ion-removed aqueous solution obtained by recovering only lithium ions from the lithium hydroxide aqueous solution to the recovery liquid using the lithium ion separation device provided with the Li selective permeation membrane, the organic acid metal is used in the electrochemical device. supplied to the That's what it means.
  • the organic acid metal is by-produced along with the lithium hydroxide, and an aqueous solution containing these is obtained.
  • the lithium hydroxide is removed from the aqueous solution containing the lithium hydroxide and the organic acid metal by recovering only the lithium ions using a lithium ion separator, a Li ion-removed aqueous solution containing the organic acid metal is obtained.
  • the by-produced organic acid metal is treated with an organic acid metal aqueous solution (Li ion It is intended to recover an organic acid such as acetic acid from the organic acid metal aqueous solution (Li ion-removed aqueous solution) by supplying it to an electrochemical device as an aqueous solution for removing Li ions.
  • a separated liquid 1 obtained by crystallization and solid-liquid separation 1 from the aqueous solution containing lithium hydroxide and organic acid metal is supplied to the electrochemical device as an organic acid metal aqueous solution. It will happen.
  • Li ion removal aqueous solution or separation solution 1 By reusing the organic acid metal aqueous solution containing the organic acid metal by-produced in the lithium ion separation device (Li ion removal aqueous solution or separation solution 1) in this way, waste can be reduced.
  • the fact that the organic acid metal aqueous solution (the Li ion-removed aqueous solution or separation solution 1) can be reused is an advantage of focusing on the reaction using an organic acid such as acetic acid.
  • the lithium hydroxide aqueous solution is generated by reacting the separated liquid 4 obtained by the solid-liquid separation 4 with the metal hydroxide, That's what it means.
  • the separated liquid 4 obtained by removing the precipitated heavy metals by the solid-liquid separation 4 is an organic acid lithium aqueous solution with few impurities.
  • the method for producing a lithium compound according to the eighth aspect of the present embodiment includes, in the above third to seventh aspects, Furthermore, adding carbon dioxide to the recovered liquid and performing solid-liquid separation 5; including The lithium carbonate contained in the separated liquid 5 obtained by performing the solid-liquid separation 5 is used to generate the aqueous lithium organic acid solution, That's what it means.
  • the recovered liquid is obtained by recovering only lithium ions with a lithium ion separator, and as described above, it is an aqueous solution of lithium hydroxide with few impurities. is obtained. By subjecting this to solid-liquid separation 5, high-purity lithium carbonate with few impurities can be obtained.
  • the separated liquid 5 obtained by the solid-liquid separation 5 becomes a saturated aqueous solution of lithium carbonate in which lithium carbonate is dissolved, so it can be used as lithium carbonate in generating an aqueous lithium acetate solution. By using the separated liquid 5 as a lithium carbonate source, it is possible to cope with various operating conditions.
  • the reaction between the organic acid such as acetic acid and the lithium carbonate produces carbon dioxide together with the lithium organic acid.
  • This carbon dioxide In the lithium ion separator, only lithium ions are recovered and used as carbon dioxide to be added to the recovered liquid, which is an aqueous solution of lithium hydroxide containing few impurities, so that the amount of carbon dioxide to be discarded can be reduced.
  • a method for producing a lithium compound according to the tenth aspect of the present embodiment is, in the above first to ninth aspects, Obtaining lithium hydroxide by solid-liquid separation 1, That's what it means.
  • the lithium hydroxide aqueous solution obtained by producing the lithium hydroxide aqueous solution is crystallized, preferably the lithium ion separation apparatus of the fourth aspect above is used to recover the Crystallized recovered liquid is provided. Therefore, the separated solid 1-1 obtained by the solid-liquid separation 1 becomes lithium hydroxide with high purity. That is, it can be said that the tenth mode is a mode in which the lithium compound produced by the method for producing a lithium compound of the present embodiment is lithium hydroxide.
  • the method for producing a lithium compound according to the eleventh aspect of the present embodiment is the step of obtaining lithium carbonate by performing solid-liquid separation 5 in the eighth to tenth aspects.
  • the solid-liquid separation 5 as described above, only lithium ions are recovered with the lithium ion separator, and carbon dioxide is added to the recovered liquid, which is an aqueous lithium hydroxide solution with few impurities, to remove lithium carbonate.
  • the method for producing a lithium compound according to the twelfth aspect of the present embodiment is the above-described first to eleventh aspects, the metal forming the metal hydroxide and the metal forming the organic acid metal are the same; That's what it means.
  • the metal hydroxide is used by producing the aqueous solution of lithium hydroxide, and the organic acid metal is produced as a by-product by producing the aqueous solution of lithium hydroxide, and is supplied to an electrochemical device to produce acetic acid or the like. of the organic acid is regenerated, and the metal is regenerated as a metal hydroxide. Then, the recovered metal hydroxide is used by generating a lithium hydroxide aqueous solution. That is, the twelfth mode is a mode that means that the metal is circulated, and by doing so, it is possible to reduce the amount of waste.
  • the method for producing a lithium compound according to the thirteenth form of the present embodiment is the above-described first to twelfth forms,
  • the metal is at least one selected from sodium, potassium and barium, That's what it means. When the metal is one of these, the reaction in producing the lithium hydroxide aqueous solution proceeds more rapidly, and it is easier to regenerate with an electrochemical device, so lithium hydroxide can be produced efficiently.
  • the apparatus for producing a lithium compound according to the fourteenth form of the present embodiment includes: Equipped with a reaction vessel 1, a reaction vessel 2, an electrochemical device and a return pipe,
  • the reaction tank 1 is a tank for mixing lithium carbonate, an acid containing an organic acid, and water to produce an aqueous lithium organic acid solution
  • the reaction tank 2 is a tank for mixing the aqueous lithium organic acid solution and the metal hydroxide to produce an aqueous lithium hydroxide solution
  • the electrochemical device is a device for regenerating the organic acid used in generating the aqueous lithium organic acid solution from an aqueous solution obtained by removing lithium hydroxide from the aqueous lithium hydroxide solution
  • the return pipe is a pipe for returning the regenerated organic acid to the reaction vessel 1, Lithium compound manufacturing equipment, is.
  • the apparatus for producing a lithium compound generates an aqueous solution of lithium organic acid (reaction tank 1), an aqueous solution of lithium hydroxide (reaction tank 2), and an aqueous solution of lithium hydroxide.
  • An organic acid such as acetic acid is regenerated from the generated organic acid metal (electrochemical device), and the regenerated organic acid can be returned to the reaction vessel 1 via a return pipe for use. It is suitably used in a method for producing a compound. That is, according to the apparatus for producing a lithium compound of the present embodiment, it is possible to efficiently produce a high-purity lithium compound from low-grade lithium carbonate containing impurities such as brine.
  • the apparatus for producing a lithium compound according to the fifteenth form of the present embodiment is, in the above fourteenth form, Further, comprising a lithium ion separation device equipped with a Li permselective membrane that recovers only lithium ions from the lithium hydroxide aqueous solution into a recovery liquid, That's what it means.
  • the apparatus for producing a lithium compound according to the sixteenth form of the present embodiment in the above fifteenth form, Furthermore, a crystallizer for crystallizing the recovered liquid is provided, That's what it means. Providing a crystallizer makes it easier to obtain lithium hydroxide with higher purity.
  • the method for producing the lithium compound of this embodiment includes mixing lithium carbonate, an acid containing an organic acid, and water in a reaction vessel 1 to produce an aqueous lithium organic acid solution containing lithium organic acid;
  • the organic acid lithium aqueous solution and the metal hydroxide are mixed in the reaction vessel 2 to generate the lithium hydroxide aqueous solution, and the organic acid metal by-produced by the generation of the lithium hydroxide aqueous solution is subjected to electrochemical reaction. returning the organic acid regenerated using the apparatus to the reaction vessel 1 and using it as the organic acid; It is characterized by comprising
  • FIGS. 1 to 4 are flow diagrams showing a preferred embodiment of a lithium hydroxide production apparatus capable of carrying out the method for producing a lithium compound of the present embodiment.
  • FIGS. 1 and 2 show flow charts in the case of adopting method 2 as a method for obtaining high-purity lithium hydroxide from an aqueous lithium hydroxide solution, and FIG.
  • FIG. 2 shows a flow diagram when the ion exchange membrane is a cation exchange membrane (cation exchange membrane).
  • FIG. 3 is a flow diagram when Method 1 is adopted and the ion exchange membrane used in the electrochemical device is an anion exchange membrane (anion exchange membrane).
  • liquid 1 organic acid such as acetic acid
  • crude lithium carbonate low-grade lithium carbonate
  • separated liquid 5 obtained by solid-liquid separation 5
  • liquid 3 Lithium carbonate solution
  • reaction vessel 1 liquid 1 (organic acid such as acetic acid), crude lithium carbonate (low-grade lithium carbonate) as a raw material, and separated liquid 5 obtained by solid-liquid separation 5
  • liquid 3 Lithium carbonate solution
  • reaction vessel 1 aqueous solution A (aqueous solution of lithium organic acid)
  • aqueous solution B aqueous solution containing metal hydroxide
  • aqueous solution C Lithium hydroxide aqueous solution
  • reaction tank 1 lithium carbonate and an organic acid such as acetic acid are reacted to produce an organic acid lithium aqueous solution containing organic acid lithium, and in the reaction tank 2, the organic acid lithium and metal Hydroxide and are reacted to form a lithium hydroxide aqueous solution.
  • the aqueous solution C produced in the reaction tank 2 is fed to the lithium ion separation device 10 equipped with the Li permselective membrane 10c as a stock solution. Lithium ions alone are recovered to form a Li ion-removed aqueous solution, which is supplied to an electrochemical device as an organic acid metal aqueous solution.
  • aqueous solution C undergoes crystallization and solid-liquid separation 1 to obtain lithium hydroxide as separated solid 1-2, and separated liquid 1-2, which is an aqueous solution containing metal acetate, is obtained. and the separated liquid 1-2 is supplied to the electrochemical device as an organic acid metal aqueous solution.
  • an organic acid such as acetic acid is regenerated from an organic acid metal by-produced by generating a lithium hydroxide aqueous solution.
  • ion exchange membrane such as an anion exchange membrane (anion exchange membrane) or a cation exchange membrane (cation exchange membrane) is used as the ion exchange membrane used in the electrochemical device.
  • anion exchange membrane anion exchange membrane
  • cation exchange membrane cation exchange membrane
  • the recovered liquid obtained by recovering only lithium ions from the lithium hydroxide aqueous solution becomes high-purity lithium hydroxide through crystallization and solid-liquid separation 1, or High-purity lithium carbonate is obtained by the reaction with the mixed gas containing carbon dioxide which is by-produced in the reaction of mixing lithium carbonate with an organic acid such as acetic acid in 1.
  • the Li ion-removed aqueous solution obtained by recovering only lithium ions from the lithium hydroxide aqueous solution is supplied to the electrochemical device as the organic acid metal aqueous solution containing the organic acid metal produced in the reaction tank 2 .
  • the electrochemical device As already mentioned, it is supplied to the electrochemical device as catholyte or as anolyte, depending on the type of ion-exchange membrane that the electrochemical device has.
  • the separated liquid 1-1 after removing lithium hydroxide from the recovered liquid through crystallization and solid-liquid separation 1 is an aqueous solution containing a very small amount of lithium hydroxide, and is shown in FIGS. It may be supplied to the recovered liquid tank 10b of the lithium ion separator 10 so that the
  • the production method of the present embodiment includes mixing lithium carbonate, an acid containing an organic acid, and water in a reaction vessel 1 to produce an aqueous solution of lithium organic acid containing lithium organic acid.
  • Lithium carbonate is usually supplied in the form of a slurry, and an acid containing an organic acid such as acetic acid is supplied as an aqueous solution.
  • An organic acid lithium aqueous solution containing the organic acid lithium is obtained.
  • the reaction between lithium carbonate and an acid containing acetic acid is represented by the following chemical reaction formula (1).
  • the lithium acetate battery material chamber produced by the reaction below dissolves in water in the reaction vessel and exists in a state in which acetate ions and lithium ions are separated, forming an aqueous solution containing lithium ions.
  • organic acids examples include acetic acid, formic acid, propionic acid, butanoic acid, and the like, represented by the general formula R 1 —COOH (where R 1 is a hydrogen atom or an aliphatic hydrocarbon group).
  • R 1 is a hydrogen atom or an aliphatic hydrocarbon group
  • monovalent carboxylic acid having one carboxyl group general formula R 2 —(COOH) 2 (R 2 is a single bond or aliphatic a hydrogen group), a divalent carboxylic acid having two carboxyl groups
  • R 3 —(COOH) 3 R 3 is a single bond or an aliphatic hydrocarbon group
  • a trivalent carboxylic acid having three carboxyl groups, represented by ), and the like are preferred.
  • the aliphatic hydrocarbon group for R 1 in the general formula of the monovalent carboxylic acid is preferably an alkyl group or an alkenyl group in consideration of reactivity when mixed with lithium carbonate, availability, cost, etc., and alkyl groups are more preferred.
  • a hydrogen atom is also preferable from the same point of view.
  • the aliphatic hydrocarbon group for R 1 may be linear or branched, and is preferably linear in consideration of reactivity in mixing with lithium carbonate, availability, cost, and the like. From the same viewpoint, the number of carbon atoms in the aliphatic hydrocarbon group is preferably 1 or more, and the upper limit is preferably 8 or less, more preferably 4 or less, still more preferably 3 or less, and even more preferably 2 or less. is. In addition, the aliphatic hydrocarbon group of R 1 may be substituted with a fluorine atom, a halogen atom such as a chlorine atom, a hydroxyl group, or the like.
  • the aliphatic hydrocarbon group for R 2 in the general formula of the divalent carboxylic acid is an alkylene (alkanediyl) group or an alkenylene (alkenediyl) group in consideration of reactivity in mixing with lithium carbonate, availability, cost, etc. groups are preferred, and alkylene (alkanediyl) groups are more preferred.
  • a single bond is also preferable from the same point of view.
  • the aliphatic hydrocarbon group for R 2 may be linear or branched, and is preferably linear in consideration of reactivity in mixing with lithium carbonate, availability, cost, and the like. From the same viewpoint, the number of carbon atoms in the aliphatic hydrocarbon group is preferably 1 or more, and the upper limit is preferably 8 or less, more preferably 4 or less, still more preferably 3 or less, and even more preferably 2 or less. is.
  • the aliphatic hydrocarbon group of R 2 may be substituted with a fluorine atom, a halogen atom such as a chlorine atom, a hydroxyl group, or the like.
  • an alkanetriyl group and an alkenetriyl group are preferable in consideration of reactivity in mixing with lithium carbonate, availability, cost, and the like. and more preferably an alkanetriyl group.
  • the aliphatic hydrocarbon group for R 3 may be linear or branched, and is preferably linear in consideration of reactivity in mixing with lithium carbonate, availability, cost, and the like. From the same viewpoint, the number of carbon atoms in the aliphatic hydrocarbon group is preferably 1 or more, and the upper limit is preferably 8 or less, more preferably 4 or less, and still more preferably 3 or less.
  • the aliphatic hydrocarbon group of R 3 may be substituted with a fluorine atom, a halogen atom such as a chlorine atom, a hydroxyl group, or the like, and is preferably substituted with a hydroxyl group.
  • the monovalent carboxylic acid is preferably formic acid or acetic acid, particularly preferably acetic acid, and the divalent carboxylic acid is preferably oxalic acid.
  • Citric acid is preferred as the trivalent carboxylic acid.
  • Lithium carbonate and an acid including an organic acid such as acetic acid are highly reactive, so the reaction proceeds rapidly. Therefore, heating is not necessary, but heating may be performed if necessary, in which case the temperature is room temperature (23°C) to 120°C, preferably room temperature (23°C) to 80°C. Further, as shown in the above chemical reaction formula (1), the amount of the organic acid such as acetic acid to be used may be twice the molar ratio of lithium carbonate. may be supplied. Excessive supply improves the yield of lithium acetate, so that lithium hydroxide can be produced more efficiently.
  • Lithium carbonate used in generating the lithium organic acid aqueous solution is a starting material in the production method of the present embodiment, that is, a raw material for producing lithium hydroxide.
  • Examples of lithium carbonate include salt lake brine, geothermal brine, etc., as well as low-grade lithium carbonate obtained from seawater, mining wastewater, and lithium-containing treated water extracted from treated materials for lithium secondary batteries. .
  • the lithium carbonate used in the manufacturing method of the present embodiment does not need to be special reagent grade.
  • the low-grade lithium carbonate obtained from the brine or the like which can be used in the production method of the present embodiment, contains moisture due to moisture absorption or brine, and various other impurities.
  • low-grade lithium carbonate usually contains lithium, boron, sodium, potassium, magnesium, calcium, etc., and the content of these is usually 5,000 to 300,000 mass ppm as metal atoms, 200 mass ppm, 300 to 2,000 mass ppm, 100 to 800 mass ppm, 200 to 1,500 mass ppm, and 1,500 to 4,500 mass ppm.
  • Low-grade lithium carbonate may contain chlorine in addition to the above, and the content in that case is usually 300 to 2,000 ppm by mass, and may contain aluminum, zinc, lead, etc.
  • the content of these metal atoms is usually 0.5 to 50 ppm by mass, 0.1 to 10 ppm by mass, and 0.1 to 20 ppm by mass. It may also contain sulfate, usually in a content of 50 to 1,000 mass ppm as SO 4 . It should be noted that the low-grade lithium carbonate used in the production method of the present embodiment changes depending on the properties of the brackish water, so what the low-grade lithium carbonate can contain is not limited to the above. , needless to say.
  • the acid containing an organic acid such as acetic acid includes the organic acid such as acetic acid described above, and the reaction represented by the above chemical reaction formula (1) may proceed. Even if the entire amount is an organic acid such as acetic acid Alternatively, acids other than organic acids such as acetic acid may be contained. From the viewpoint of obtaining lithium hydroxide more efficiently, the total amount is preferably an organic acid such as acetic acid. In this case, the organic acids described above may be used singly or in combination. Inorganic acids such as hydrochloric acid and sulfuric acid can be used as acids other than organic acids such as acetic acid. Moreover, you may use several organic acids.
  • the method of supplying lithium carbonate, water, and organic acid to the reaction tank 1 is not particularly limited as long as they can be mixed in the reaction tank 1 as a result.
  • the organic acid is supplied directly to the reaction vessel 1, or the organic acid is mixed with water, added to the low-grade lithium carbonate, and supplied to the reaction vessel 1 as a slurry. method.
  • the production method of the present embodiment includes reacting an organic acid lithium such as lithium acetate with a metal hydroxide to produce a lithium hydroxide aqueous solution.
  • an organic acid lithium such as lithium acetate
  • a metal hydroxide for example, when acetic acid is used as the organic acid and lithium acetate is used as the organic acid lithium, the reaction between lithium acetate and metal hydroxide is represented by the following chemical reaction formula (2).
  • lithium organic acids such as lithium acetate and metal hydroxides are highly reactive like acids containing organic acids such as lithium carbonate and acetic acid, so the reaction progresses quickly. Therefore, heating is not necessary, but heating may be performed if necessary, in which case the temperature is room temperature (23°C) to 120°C, preferably room temperature (23°C) to 80°C.
  • the room temperature is indicated as 23° C. for convenience, but it is described for convenience only, and the above temperature conditions do not mean that the temperature is 23° C. or higher. is meant to be
  • metal hydroxide examples include sodium hydroxide, potassium hydroxide, barium hydroxide, and the like, with sodium hydroxide and potassium hydroxide being more preferred, and potassium hydroxide being even more preferred.
  • the reaction represented by the chemical reaction formula (2) proceeds easily, and lithium hydroxide can be obtained efficiently.
  • metal hydroxides may be used singly or in combination, but from the viewpoint of simplifying the production method and improving efficiency, it is preferable to use one kind of metal hydroxide.
  • the organic acid such as acetic acid used in generating the organic acid lithium aqueous solution containing the organic acid lithium such as lithium acetate is combined with "CH 3 COOMe" in the chemical reaction formula (2), That is, it is regenerated using an electrochemical apparatus from an organic acid metal such as metal acetate that is by-produced by producing a lithium hydroxide aqueous solution.
  • the electrochemical device is not particularly limited as long as it can be electrolyzed.
  • As the exchange membrane a cation exchange membrane (cation exchange membrane) and an anion exchange membrane (anion exchange membrane) are employed.
  • Bipolar membrane type electrochemical devices can also be used, in which case anion exchange membranes (anion exchange membranes) and cation exchange membranes (cation exchange membranes) and bipolar ion exchange membranes (anion exchange membranes and A membrane consisting of a cation exchange layer) is used.
  • anion exchange membranes anion exchange membranes
  • cation exchange membranes cation exchange membranes
  • bipolar ion exchange membranes anion exchange membranes and A membrane consisting of a cation exchange layer
  • the anion exchange membrane can be used without particular limitation as long as it can recover organic acid ions such as acetate ions. Strongly basic anion exchange resins and weakly basic anions having amino groups as functional groups An anion exchange membrane using an exchange resin or a strongly basic anion exchange resin having a quaternary ammonium group is preferred.
  • As the cation exchange membrane any one can be used without particular limitation as long as it can recover sodium ions and the like.
  • Neosepta CSE manufactured by Astom
  • Selemion manufactured by AGC Engineering Co., Ltd.
  • hydrocarbon-based cation exchange membrane etc.
  • a device as shown in FIG. 5 is preferably used.
  • the electrochemical device shown in FIG. 5 comprises an anode 1 , a cathode 2 and a plurality of anion exchange membranes 3 .
  • the liquid 2 supplied as the catholyte to the cathode side of the electrochemical device, the aqueous solution A supplied to the anode side as the anolyte solution, and the liquid 1 and the aqueous solution B discharged from the electrochemical device are anion exchange membranes.
  • the ion-exchange membranes included in the electrochemical device are cation-exchange membranes, they can have a plurality of cation-exchange membranes as in the case of the anion-exchange membranes.
  • the liquid 2 supplied as the catholyte and the anolyte is an aqueous solution containing an organic acid metal such as a metal acetate that is by-produced by producing the aqueous lithium hydroxide solution, preferably by producing the aqueous lithium hydroxide solution. It is an aqueous solution containing an organic acid metal such as a metal acetate that is by-produced after lithium hydroxide is recovered from the resulting aqueous solution.
  • Liquid 2 more specifically contains an organic acid metal aqueous solution as shown in FIGS.
  • the organic acid metal aqueous solution includes a Li ion-removed aqueous solution containing an organic acid metal obtained by removing lithium hydroxide from an aqueous lithium hydroxide solution by recovering only lithium ions using a lithium ion separator (FIGS. 3 and 4). reference). Further, when method 2 is employed, a separated liquid 1-2 is obtained by crystallizing an aqueous lithium hydroxide solution and performing solid-liquid separation 1.
  • organic acid ions such as acetate ions are recovered in the anolyte from organic acid metals such as metal acetate contained in the catholyte (see FIGS. 1 and 2).
  • the liquid 2, which is the catholyte is a Li ion-removed aqueous solution obtained by a lithium ion separator, or a solid liquid.
  • the aqueous solution B may be included together with the separated liquid 1-2 obtained by the separation 1.
  • a cation exchange membrane is employed as the ion exchange membrane of the electrochemical device, as shown in FIGS. A separated liquid 1-2 obtained by the solid-liquid separation 1 is obtained.
  • the organic acid lithium solution and potassium hydroxide (aqueous solution A) obtained by generating the organic acid lithium solution are circulated. It is preferable to use By using an aqueous solution with a high salt concentration, it is possible to reduce the electric power required for diaphragm electrolysis when, for example, a diaphragm-type electrochemical device is employed, and also to reduce waste.
  • a Li ion-removed aqueous solution organic acid metal aqueous solution
  • the aqueous solution B discharged from the cathode side of the electrochemical device is the residual liquid in which the organic acid ions are recovered from the organic acid metal contained in the liquid 2 in the case of having the anion exchange membrane shown in FIG.
  • it is a liquid in which metal ions are recovered from the organic acid metal contained in the liquid 2, and becomes an aqueous solution containing a metal hydroxide formed by the metal contained in the organic acid metal.
  • the aqueous solution B is an aqueous solution containing a metal hydroxide in any case, it is preferably used for the reaction with the lithium organic acid in the reaction tank 2 from the viewpoint of reducing waste.
  • the aqueous solution B in the case of employing the lithium ion separation device of FIGS. 3 and 4 can also be changed according to the type of ion exchange membrane possessed by the electrochemical device. .
  • the metal contained in the metal hydroxide is transferred from the metal hydroxide (aqueous solution B) through the reaction in the reaction tank 2 to the organic acid metal (aqueous solution C, separated liquid 1-2 ), and the organic acid metal (liquid 2) becomes a metal hydroxide (aqueous solution B) in the electrochemical device, so the metal is circulated.
  • the metal contained in the metal hydroxide is the organic acid metal (aqueous solution C) as in the case of FIGS. 1 and 2 above.
  • the Li-ion-removed aqueous solution (organic acid metal aqueous solution) is discharged from the lithium ion separator, and the organic acid metal (liquid 2) becomes a metal hydroxide (aqueous solution B) in the electrochemical device, so the metal circulates. It will happen. Therefore, the circulating metal is the same as the metal contained in the metal hydroxide.
  • the metal contained in the metal hydroxide is preferably sodium, potassium, barium, or the like, more preferably sodium or potassium, and still more preferably potassium. These metals may be used singly or in combination.
  • liquid 1 discharged from the electrochemical device the organic acid ions are recovered from the organic acid metal contained in the liquid 2 (Fig. 1), or the metal ions contained in the liquid 2 are removed (Fig. 2), The resulting aqueous solution contains a large amount of organic acids such as acetic acid.
  • liquid 1 is used as an organic acid such as acetic acid that reacts with lithium carbonate. The same is true when employing the lithium ion separation device shown in FIGS.
  • the above organic acid ions are recovered by an electrochemical device, hydrogen is generated from the anode and oxygen is generated from the cathode.
  • the generated hydrogen and oxygen accompany the liquid 1 discharged from the electrochemical device, and are generated as a mixed gas together with carbon dioxide in producing the lithium organic oxide aqueous solution.
  • carbon dioxide can be added as a mixed gas to the separated liquid 2, which is an aqueous lithium hydroxide solution with reduced impurities, to obtain lithium carbonate (see also FIGS. 1 and 2).
  • the mixed gas can be added to the recovered liquid discharged from the lithium ion separator to obtain lithium carbonate.
  • the lithium hydroxide aqueous solution obtained by generating the lithium hydroxide aqueous solution can be recovered by using a lithium ion separation device equipped with a Li selectively permeable membrane to recover only lithium ions in a recovery liquid.
  • a lithium ion separator By using a lithium ion separator, high-purity lithium hydroxide can be obtained without using chemicals, and high-purity lithium hydroxide can be easily obtained only by crystallizing the recovered liquid.
  • the lithium ion separation device 10 includes a raw liquid tank 10a that supplies an aqueous solution C (lithium hydroxide aqueous solution), a recovered liquid tank 10b that stores a recovered liquid, and a lithium ion separator that selectively permeates only lithium ions.
  • This device is provided with a Li permselective membrane 10c that allows
  • lithium ions contained in the aqueous solution C (lithium hydroxide aqueous solution) supplied to the undiluted solution tank 10a pass through the Li permselective membrane 10c and are recovered in the recovery liquid.
  • the lithium ion separator 10 includes a first electrode 10d (anode) in one tank (raw liquid tank 10a side) and a second electrode 10e (cathode) in the other tank (recovery liquid tank 10b side). It is shown. In this way, the lithium ions move from the anode side to the cathode side, thereby moving from the aqueous solution C (lithium hydroxide aqueous solution) supplied to the undiluted solution tank 10a to the recovered liquid in the recovered liquid tank 10b.
  • aqueous solution C lithium hydroxide aqueous solution
  • the lithium ions recovered in the recovery liquid are separated from the lithium hydroxide produced in crystallization such as evaporation crystallization and cooling crystallization, and the filtrate is separated by solid-liquid separation or the like, and the lithium hydroxide is further dried as necessary. By performing such as, high-purity lithium hydroxide is obtained.
  • the lithium ion separation device 10 may have a storage tank (not shown) for storing the undiluted liquid and the recovered liquid in the undiluted liquid tank 10a and the recovered liquid tank 10b.
  • a storage tank (not shown) for storing the undiluted liquid and the recovered liquid in the undiluted liquid tank 10a and the recovered liquid tank 10b.
  • the recovered liquid from which lithium ions are recovered is temporarily stored in the storage tank, and the lithium ions contained in the recovered liquid in the storage tank are stored.
  • concentration of is above a certain level, it is possible to crystallize the recovered liquid from the storage tank and perform processing such as solid-liquid separation as necessary to obtain lithium hydroxide as a product.
  • processing such as solid-liquid separation as necessary to obtain lithium hydroxide as a product.
  • the aqueous solution C from the reaction tank 2 is temporarily stored and then supplied to the stock solution tank 10a of the lithium ion separation device 10 depending on the circulation of the stock solution and the operating conditions of the lithium ion separation device. Also, depending on the operating conditions of the electrochemical device, it is possible to temporarily store the Li ion-removed aqueous solution after the lithium ions have been recovered in the lithium ion separator 10 in a storage tank and supply it to the electrochemical device. can.
  • the lithium ion separation device 10 used in the production method of the present embodiment is divided into a raw liquid tank 10a and a recovered liquid tank 10b in one tank by a Li permselective membrane 10c. It may be in a form in which the tanks are separated, or in a form in which two tanks, the undiluted solution tank 10a and the recovery liquid tank 10b, are connected via the Li selective permeable membrane 10c.
  • the Li permselective membrane is a membrane having a function of transferring Li ions in the aqueous solution C (aqueous lithium hydroxide solution) serving as the stock solution to the recovery liquid. (see FIGS. 3 and 4).
  • the Li selectively permeable membrane is supplied with a Li selectively permeable membrane body composed of a super Li ion conductor (ionic conductor) having particularly high ionic conductivity, and an aqueous solution C (aqueous lithium hydroxide solution) as its stock solution. It is preferably composed of a Li adsorption layer formed as a thin layer on the side.
  • the Li recovery efficiency can be enhanced by increasing the ion current of Li ions flowing between the electrodes.
  • the Li ions contained in the aqueous solution exist as Li hydrated ions with water molecules coordinated around them. Therefore, in order to further increase the ion current, it is effective to realize a condition in which water molecules are easily removed from the surface of the Li selective permeable membrane (the interface between the Li selective permeable membrane and the undiluted solution). Therefore, it is preferable that a Li adsorption layer that adsorbs Li ions (excluding hydrates) in the Li ion extract is formed on the surface of the Li selectively permeable membrane.
  • the Li permselective membrane is subjected to surface Li adsorption treatment.
  • the Li adsorption layer is preferably formed by modifying the surface of the material constituting the Li selective permeation membrane, as will be described later.
  • the material constituting the Li selectively permeable membrane main body for example, the following Li-containing oxides, oxynitrides, and the like are preferably exemplified. That is, the Li selectively permeable membrane preferably contains the following Li-containing oxides, oxynitrides, and the like.
  • these materials can be obtained, for example, as a sintered body by mixing particles composed of this material with a sintering aid or the like and sintering the mixture at a high temperature (1000°C or higher).
  • the surface of the Li permselective membrane can also be configured as a porous structure in which fine particles composed of LLTO are bonded (sintered), so the effective area of the surface of the Li permselective membrane body can be raised.
  • LLTO a sintering aid or the like
  • Li-substituted NASICON Na Super Ionic Conductor
  • NASICON Na Super Ionic Conductor
  • Li 1+x+y Al x (Ti, Ge) 2-x Si y P 3-y O 12 (where 0 ⁇ x ⁇ 0.6, 0 ⁇ y ⁇ 0.6) (Li 2 O ⁇ Al 2 O 3 —SiO 2 —P 2 O 5 —TiO 2 —GeO 2 system (hereinafter also referred to as “LASiPTiGeO”).
  • Li PON lithium oxynitride phosphate
  • LLTO LLTO
  • LLZON nitrides of LLZO
  • LASiPTiGeON nitrides of LASiPTiGeO.
  • Li-containing oxides, oxynitrides, and other super Li-ion conductors contain Li as one of their constituent elements, and Li ions outside the crystal move between Li sites in the crystal to Conductivity develops. Li ions flow through the Li permselective membrane body, but sodium ions cannot flow within the Li permselective membrane. At this time, it is Li ions (Li + ) that conduct in the crystal, and Li hydrate ions that are present in the stock solution together with the Li ions cannot enter the Li site and therefore do not conduct in the crystal. This point is the same as the Li permselective membrane described in WO2015/020121.
  • the Li permselective membrane may not have an anode and a cathode, or may have an anode and a cathode joined together.
  • an anode and a cathode it is preferable that the anode is installed on the undiluted liquid side of the Li permselective membrane and the cathode is installed on the recovered liquid side.
  • the solid-liquid interfaces on the undiluted liquid side and recovered liquid side of the Li selective permeable membrane are maintained at positive potential and negative potential, respectively, and lithium ions can be recovered.
  • materials for the anode and cathode metal materials that do not cause electrochemical reactions in the undiluted solution and the recovered solution can be appropriately used, respectively. Examples of such metal materials include SUS, Ti, Pt, Ni, Ti--Ir alloys, and alloys thereof.
  • the above material used as the Li selective permeable membrane is solid, it is known that it exhibits conductivity when Li ions flow in the crystal in a form close to free electrons. Therefore, when the anode is at a positive potential and the cathode is at a negative potential, among the Li ions (positive ions) in the stock solution on the anode side, those that reach the cathode side of the Li permselective membrane are the Li permselective membrane. flows from the anode side (undiluted liquid) toward the cathode side (recovered liquid) by ion conduction. The Li ions that have reached the cathode side of the Li selectively permeable membrane are recovered in the recovery liquid. Therefore, after a predetermined period of time has elapsed, the Li ion concentration in the undiluted solution decreases and the Li ion concentration in the recovered solution increases.
  • the Li adsorption layer is formed as a thin layer on the surface of the Li permselective membrane body by chemically treating the Li permselective membrane body.
  • one main surface of the Li permselective membrane main body for example, LLTO
  • LLTO Li permselective membrane main body
  • hydrochloric acid or nitric acid for five days.
  • HLTO a substance layer with a composition close to H 0.29 La 0.57 TiO 3 in which Li, which is particularly easily oxidized among the constituent elements of the Li selective permeable membrane main body (for example, LLTO), is replaced with hydrogen in the acid.
  • HLTO thin layer
  • HLTO Since the H site in HLTO was originally a site where Li enters, H is particularly easily replaced by Li ions, and is difficult to be replaced by other ions (such as sodium ions). Therefore, HLTO functions as a Li adsorption layer. In addition, HLTO is formed only on the outermost surface of the Li permselective membrane because it is produced by reaction with acid.
  • the lithium ion separation device may be equipped with a heater that heats the recovered liquid.
  • a heater that heats the recovered liquid.
  • the solubility of lithium ions in the recovery liquid is increased, and lithium ions are supplied from the lithium hydroxide aqueous solution, which is the stock solution, by the increased amount, so that a large amount of lithium ions can be recovered.
  • the heating temperature is preferably 50° C. or higher, more preferably 60° C. or higher, still more preferably 70° C. or higher, particularly preferably 80° C. or higher, and the upper limit is preferably 100° C. or lower, more preferably 100° C. or lower. is 95° C. or less, more preferably 90° C. or less.
  • the type of the heater is not particularly limited, and for example, jacket type or heater type heat exchangers using electricity, heat medium, etc. can be used.
  • part of the recovered liquid can be heated by circulating it while passing it through a heater. In this case, a shell-and-tube heat exchanger can be used.
  • the pH of the aqueous solution C (lithium hydroxide aqueous solution) serving as the stock solution may be controlled. Lithium ions can be efficiently recovered by controlling the pH. In this case, it is preferable to adjust the pH within the range of 12 or more and 14 or less. It should be noted that the pH of 12 or more and 14 or less is the adjustment target, and in this embodiment, for pH 12 or more and 14 or less, the pH of the undiluted solution is a value of 11.5 or more and less than 12.5 for pH 12. , pH 14 includes a value of 13.5 or more and less than 14.5, and substantially means a range of 11.5 or more and less than 14.5.
  • the aqueous solution C (lithium hydroxide aqueous solution) to be the stock solution may be adjusted in temperature in the same manner as the recovered solution, and more specifically, may be heated.
  • the temperature of the recovery liquid can be easily adjusted to 50° C. or higher, and lithium ions can be recovered with high efficiency.
  • the adjustment temperature may be within the adjustment range of the temperature of the recovery solution.
  • the method is not particularly limited as long as lithium hydroxide can be obtained from the recovered liquid, and preferred examples thereof include a method by filtration, cooling crystallization, evaporation crystallization, pH crystallization, etc., and more efficiently obtain high-purity hydroxide. Evaporative crystallization is more preferable from the viewpoint of obtaining lithium.
  • the lithium ion separator when the aqueous solution C (lithium hydroxide aqueous solution) as the recovery liquid and the stock solution is heated, the energy required for evaporation can be reduced, and thus evaporative crystallization is preferably employed.
  • the specific method is not particularly limited as long as it is carried out by a normal evaporative crystallization technique, and for example, it is preferably carried out while adjusting the temperature to preferably 80°C or higher and 100°C or lower. From the viewpoint of performing evaporative crystallization more efficiently, the controlled temperature is more preferably 85° C. or higher, still more preferably 90° C. or higher.
  • the evaporative crystallization is preferably carried out under a reduced pressure atmosphere.
  • the pressure By reducing the pressure, the water vapor generated in the system can be discharged, and it can be reused by adding it to the recovered liquid or the like.
  • the vacuum pressure may generally be about 0.05 to 10 kPa, preferably 0.1 to 5 kPa, more preferably 0.1 to 5 kPa, more preferably from the viewpoint of more efficient evaporative crystallization. It is 0.2 to 1 kPa.
  • Evaporative crystallization may be performed while supplying an inert gas, and nitrogen gas, argon gas, or the like may be used as the inert gas in this case.
  • gases containing oxygen may be used as long as the concentration of carbon monoxide, carbon dioxide, or hydrocarbons is 10 ppm or less.
  • it is preferably 1 ppm or less, more preferably 0.1 ppm.
  • Lithium hydroxide is obtained as a separated solid 1-1 by performing solid-liquid separation 1 on the liquid in which lithium hydroxide crystallizes obtained by the above crystallization.
  • the separated solid 1-1 is preferably washed with ethanol or the like to remove impurities.
  • Solid-liquid separation 1 may be performed using a commonly used solid-liquid separator, and as the solid-liquid separator, a vacuum filter, a pressure filter, a centrifuge, a belt press, a screw press, or the like can be used. can. The same applies to solid-liquid separation 2 to solid-liquid separation 5, which will be described later.
  • the purified lithium hydroxide is obtained by removing the ethanol, preferably by drying at room temperature.
  • the lithium hydroxide of the separated solid 1-1 has a high purity and can be handled as a product produced by the production method of the present embodiment. Also, in this case (when method 1 is employed), the recovered liquid obtained in the lithium ion separator recovers only lithium ions, so the impurity is extremely low, and is preferably employed in method 2. Re-dissolution Treatments such as remelting in a tank and purification using a metal remover are unnecessary.
  • the separated liquid 1-1 which is the liquid after separating the lithium hydroxide of the separated solid 1-1, is an aqueous solution containing a trace amount of lithium hydroxide that could not be separated by crystallization.
  • the separated liquid 1-1 may be supplied to the recovery liquid tank of the lithium ion separation device as shown in FIGS.
  • the lithium hydroxide aqueous solution obtained by generating the lithium hydroxide aqueous solution may be crystallized.
  • the aqueous lithium hydroxide solution is obtained through crystallization, solid-liquid separation, redissolution, and impurity removal without using a lithium ion separator.
  • the method of crystallization includes a method by filtration, a method by heat concentration, a method by pH crystallization, and the like. is preferred.
  • pH crystallization can be performed, for example, by dropping an aqueous solution containing a metal hydroxide into an aqueous lithium organic acid solution.
  • the molar ratio of potassium to lithium is preferably 0.5 times or more, more It is preferably 0.75 times or more, more preferably equimolar (1.0 times) or more, and the upper limit is preferably 4.0 times or less, more preferably 3.5 times or less, further preferably 3.0 times or less.
  • the aqueous solution A aqueous solution of organic acid lithium
  • the separation liquid 4 is added dropwise when the solid-liquid separation 4 is performed to crystallize the lithium hydroxide hydrate.
  • the time for dropping the organic acid lithium aqueous solution and the potassium hydroxide aqueous solution is preferably 1 to 6 hours.
  • the liquid in which the lithium hydroxide hydrate is crystallized by the dropwise addition is preferably stirred for 15 minutes to 2 hours to ripen the lithium hydroxide crystals.
  • the crystallizer is shown as an independent device, but from the viewpoint of efficiency, in the case of method 2, the reaction vessel 2 also serves as the crystallizer. is preferred.
  • crystallization can be performed by dropping the aqueous solution A serving as seed crystals or the separation liquid 4 into the aqueous solution B serving as the mother liquor. Therefore, if the reaction tank 2 is provided with means for dripping the aqueous solution A or the separated liquid 4, crystallization can be performed simultaneously with the reaction between the lithium organic oxide and the metal hydroxide. need not be set.
  • the separated solid 1-2 obtained by performing solid-liquid separation 1 on the liquid in which lithium hydroxide is crystallized, which is obtained by aging the crystals of lithium hydroxide, is preferably washed with ethanol or the like to remove impurities.
  • solid-liquid separation 1 may be performed using a commonly used solid-liquid separation device, similar to solid-liquid separation 1 in method 1 above. Filters, centrifuges, belt presses, screw presses and the like can be used.
  • the purified lithium hydroxide is obtained by removing the ethanol, preferably by drying at room temperature.
  • the lithium hydroxide of the separated solid 1-2 has high purity and can be treated as a product produced by the production method of the present embodiment.
  • the purity of lithium hydroxide is improved by undergoing a treatment such as redissolution, which will be described later, it is of course possible to handle products that have undergone this treatment as products.
  • the separated liquid 1-2 obtained by the solid-liquid separation 1 is an aqueous solution containing the organic acid metal as described above, is supplied to the electrochemical device, and the organic acid ions are recovered from the organic acid metal,
  • the aqueous solution (aqueous solution B) containing the metal hydroxide is used for the reaction with the lithium organic acid to obtain lithium hydroxide.
  • Redissolution and solid-liquid separation 2 In the production method of the present embodiment, when method 2 is employed to obtain high-purity lithium hydroxide from an aqueous lithium hydroxide solution, lithium hydroxide obtained by the above crystallization and solid-liquid separation 1 (separated solid 1-2 ) to generate an aqueous lithium hydroxide solution, adding a metal removing agent for removing metals forming the organic acid metal to the aqueous solution, and performing solid-liquid separation 2.
  • Generating a lithium hydroxide aqueous solution using lithium hydroxide, which is the separated solid 1-2 is also referred to as “re-dissolving” because lithium hydroxide is converted back into a lithium hydroxide aqueous solution.
  • the aqueous solution D obtained by redissolving is an aqueous solution containing lithium hydroxide of high purity.
  • the redissolution may be performed at room temperature, or may be performed with heating as necessary.
  • heating the material can be re-melted more quickly, so that efficiency can be improved in terms of time. Therefore, the necessity of heating may be determined according to the request.
  • the heating temperature is not particularly limited, and can vary depending on the properties of the low-grade lithium carbonate used as the starting material, the scale of the apparatus, etc., so it cannot be determined unconditionally. Considering this, the temperature is preferably 40° C. or higher, more preferably 60° C. or higher, and the upper limit is preferably 90° C. or lower, more preferably 85° C. or lower.
  • the stirring time (the time required for re-dissolving) is not particularly limited, and can vary depending on the properties of the low-grade lithium carbonate used as the starting material, the scale of the apparatus, etc., so it cannot be determined indiscriminately. Considering the balance with the consumption of , it is preferably 10 minutes or more, more preferably 30 minutes or more, and the upper limit is preferably 3 hours or less, more preferably 2 hours or less, and still more preferably 1.5 hours or less.
  • the metal removing agent to be added to the aqueous solution D obtained by redissolving may be appropriately selected according to the metal to be removed.
  • Fluorosilicic acid (H 2 SiF 6 ) or the like can be preferably used.
  • the separated solid 2 obtained by the solid-liquid separation 2 contains impurities such as potassium and magnesium that can be contained in the lithium hydroxide of the separated solid 1-2. Further, the separated liquid 2 obtained by the solid-liquid separation 2 is an aqueous solution containing high-purity lithium hydroxide from which these impurities have been removed.
  • the separated liquid 3 obtained by the solid-liquid separation 3 is a saturated aqueous solution containing lithium hydroxide that has not been recrystallized by the cooling.
  • the separated liquid 3 may be used for the re-dissolution from the viewpoint of waste reduction.
  • the separated liquid 3 is a saturated aqueous solution containing lithium hydroxide, the temperature of the separated liquid 3 naturally rises to the temperature before cooling when it is redissolved, so that lithium hydroxide can be further dissolved.
  • the separation liquid 3 may be heated and used as needed.
  • lithium hydroxide When lithium hydroxide is produced by the production method of the present embodiment, the separated solid 1-2 and the separated solid 3 obtained by performing solid-liquid separation 1 and solid-liquid separation 3 can be used as products.
  • These lithium hydroxides are usually monohydrates (LiOH.H 2 O).
  • the obtained lithium hydroxide can be used as it is or after dehydration depending on the application. Dehydration of lithium hydroxide monohydrate may be carried out by conventional drying such as heating and pressure reduction.
  • the production method of the present embodiment further includes adding oxalic acid to an aqueous lithium organic acid solution (aqueous solution A) obtained by generating an aqueous lithium organic acid solution, followed by solid-liquid separation. It preferably includes doing four.
  • aqueous solution A aqueous lithium organic acid solution obtained by generating an aqueous lithium organic acid solution
  • solid-liquid separation it preferably includes doing four.
  • the separated liquid 4 obtained by the solid-liquid separation 4 becomes an organic acid lithium aqueous solution (aqueous solution A) from which impurities are removed as the separated solid 4. Therefore, it is preferable to generate the lithium hydroxide aqueous solution by the reaction between the separation liquid 4 and the metal oxide. Since solid-liquid separation 4 contains few impurities, lithium hydroxide with improved purity can be obtained as a result.
  • aqueous solution B aqueous solution containing metal hydroxide discharged from the cathode side of the electrochemical device instead of oxalic acid.
  • the production method of the present embodiment further includes adding carbon dioxide to the recovered liquid and performing solid-liquid separation 5, and by performing solid-liquid separation 5 Lithium carbonate contained in the obtained separated liquid 5 can be used to generate the lithium organic acid aqueous solution.
  • method 2 is employed to obtain high-purity lithium hydroxide from an aqueous lithium hydroxide solution, as shown in FIGS.
  • the solid-liquid separation 5 is performed, and the lithium carbonate contained in the separated liquid 5 obtained by the solid-liquid separation 5 can be used to generate the organic acid lithium aqueous solution.
  • the recovered liquid and the separated liquid 2 are aqueous solutions containing lithium hydroxide with high purity, and when carbon dioxide is added to this, lithium carbonate with high purity can be obtained.
  • lithium carbonate with high purity is obtained as the separated solid 5.
  • Lithium carbonate of the separated solid 5 is a product manufactured by the manufacturing method of the present embodiment.
  • Carbon dioxide is preferably generated by generating an aqueous lithium organic acid solution.
  • carbon dioxide is generated by reacting lithium carbonate with an organic acid such as acetic acid.
  • Carbon dioxide can be discarded as it is, but from the viewpoint of reducing waste, it is preferably used when producing lithium carbonate from lithium hydroxide.
  • liquid 1 acid containing an organic acid such as acetic acid
  • liquid 3 lithium carbonate liquid
  • the apparatus for producing a lithium compound includes: Equipped with a reaction vessel 1, a reaction vessel 2, an electrochemical device and a return pipe,
  • the reaction tank 1 is a tank for mixing lithium carbonate, an acid containing an organic acid, and water to produce an aqueous lithium organic acid solution
  • the reaction tank 2 is a tank for mixing the aqueous lithium organic acid solution and the metal hydroxide to produce an aqueous lithium hydroxide solution
  • the electrochemical device is a device for regenerating the organic acid used in generating the aqueous lithium organic acid solution from an aqueous solution obtained by removing lithium hydroxide from the aqueous lithium hydroxide solution
  • the return pipe is a pipe for returning the regenerated organic acid to the reaction vessel 1, manufacturing equipment.
  • the functions of the reaction tank 1, the reaction tank 2, and the electrochemical device that is, the reaction tank 1 performs the function of mixing and reacting lithium carbonate with an acid containing an organic acid such as acetic acid to produce an aqueous lithium organic acid solution.
  • the reaction tank 2 performs the function of mixing and reacting the lithium organic oxide aqueous solution and the metal hydroxide to produce an aqueous lithium hydroxide solution;
  • the function of regenerating the organic acid such as acetic acid obtained from the aqueous solution obtained by removing lithium hydroxide from the aqueous lithium hydroxide solution is as described in the method for producing a lithium compound of the present embodiment.
  • the reaction tank 1 and the reaction tank 2 are not particularly limited as long as they are tanks capable of performing the above reaction by mixing, and ordinary tank-shaped reaction tanks may be used. Moreover, in order to perform mixing in these reaction tanks, a stirrer may be provided as necessary, and a heating facility may be provided. Also, the configuration of the electrochemical device is as described in the method for producing a lithium compound of the present embodiment.
  • Carbon dioxide is by-produced by the reaction of mixing an organic acid such as acetic acid and lithium carbonate in the reaction tank 1, and the by-produced carbon dioxide is added to the separated liquid 2 as a mixed gas. It is dissolved in the aqueous solution A (aqueous solution of organic acid lithium) supplied from the reaction tank 1 . Carbon dioxide dissolved in the aqueous solution A becomes a factor for the production of lithium carbonate in the subsequent reaction tank 2, or in the re-dissolving tank when method 2 is employed.
  • Lithium carbonate can be an impurity when producing lithium hydroxide in the production method of the present embodiment.
  • the reaction tank 2 is equipped with a means for supplying an inert gas as a means for removing carbon dioxide in the aqueous solution.
  • the inert gas supply means is designed so that the inert gas can be supplied by bubbling.
  • an inert gas supply means that can be in an inert gas atmosphere. preferably.
  • the apparatus for producing a lithium compound of the present embodiment further includes a crystallizer for crystallizing the recovered liquid.
  • a crystallizer for crystallizing the aqueous lithium hydroxide solution is provided. By providing a crystallizer, the purity of lithium hydroxide can be improved.
  • the crystallizer included in the lithium compound manufacturing apparatus of the present embodiment is as described in the lithium compound manufacturing method of the present embodiment.
  • the reaction vessel 2 can be used in combination, and efficiency can be improved. Taking this into account, it is preferable to use the reaction vessel 2 for both purposes. If the reaction vessel 2 is equipped with a stirrer for stirring the aqueous solution B to be the mother liquor and the aqueous solution A to be dropped, and means for dropping the aqueous solution A, it can also serve as a crystallizer. In this case, no separate independent crystallizer is required.
  • Crystallization performed in the crystallizer is as described in the method for producing a lithium compound of the present embodiment, and there is no particular limitation on the form as long as the adopted crystallization method can be carried out.
  • method 1 is used to obtain high-purity lithium hydroxide from an aqueous solution of lithium hydroxide, it is preferable to use one that can be subjected to evaporative crystallization, and when method 2 is used, it is preferable to perform pH crystallization. Take what you get.
  • the production apparatus of the present embodiment is required to have a reaction vessel 1, a reaction vessel 2, an electrochemical device, and a return pipe, and preferably has a lithium ion separation device equipped with a Li permselective membrane and a crystallizer.
  • the lithium ion separator provided with the Li selectively permeable membrane is a device that is employed when method 1 is employed to obtain high-purity lithium hydroxide from an aqueous lithium hydroxide solution.
  • the configuration of the lithium ion separator is as described in the method for producing a lithium compound of the present embodiment.
  • the production device of the present embodiment does not need to use chemicals, can obtain high-purity lithium hydroxide, and can easily produce high-purity hydroxide simply by crystallizing the recovered liquid. It becomes a device that produces lithium.
  • a crystallizer for crystallizing the recovered liquid, a solid-liquid separator, and, if necessary, a dryer for drying and the like may be provided.
  • the manufacturing apparatus of the present embodiment includes a solid-liquid separation device capable of performing solid-liquid separation 1 to solid-liquid separation 5, and an organic acid such as oxalic acid as devices other than these. It may have means for supplying, means for supplying a metal removing agent, a redissolving tank for redissolving the lithium hydroxide, and means for cooling the lithium hydroxide. These apparatuses and the like may be provided according to the method employed in the method for producing a lithium compound of the present embodiment.
  • the manufacturing apparatus of this embodiment may be provided with a storage tank (not shown) as necessary.
  • a storage tank may be used to store the undiluted solution and the recovered solution.
  • the recovered liquid By installing a storage tank for the recovered liquid, the recovered liquid can be circulated and stored until the lithium ions contained in the recovered liquid reach a predetermined concentration or higher. This makes it easier to adjust the distribution of the recovered liquid, thereby improving the operability of the manufacturing apparatus of the present embodiment.
  • a storage tank for the stock solution it is easy to temporarily store the aqueous solution C and the Li ion-removed aqueous solution as the stock solution depending on the circulation of the stock solution and the operating conditions of the lithium ion separator and the electrochemical device. Therefore, the operability of the manufacturing apparatus of this embodiment is improved.
  • aqueous solutions A and B which are liquids to be supplied to the electrochemical device, for example, can also be used.
  • a storage tank that stores the liquid to be supplied to the electrochemical device it becomes easy to adjust the supply amount according to the operating state of the electrochemical device, so that the operability of the manufacturing apparatus of the present embodiment is improved. do.
  • Pure water may be supplied to the lithium ion separator and electrochemical device as needed, but by supplying it to the storage tank once and then supplying it to the electrochemical device, it is easier to manage the supply of pure water. , the operability of the manufacturing apparatus of the present embodiment is improved.
  • a storage tank for storing raw materials such as lithium carbonate, water, and organic acid may be provided.
  • water is shown feeding the lithium carbonate line.
  • Low-grade lithium carbonate (crude lithium carbonate) as a raw material is supplied in the form of slurry as described above, but a storage tank may be provided for adjusting the slurry.
  • raw materials such as low-grade lithium carbonate (crude lithium carbonate) and water may be supplied, mixed in advance, and supplied to the reaction vessel 1 in the form of a slurry.
  • the organic acid is shown to be directly supplied to the reaction vessel 1.
  • the organic acid is also temporarily stored in the storage tank in advance, and the supply amount of the organic acid can be adjusted according to the mixing state in the reaction tank 1, etc., so the operability of the production apparatus of the present embodiment is improved.
  • the purity of lithium hydroxide is determined by weighing the lithium hydroxide obtained in the example in a glove box (dew point: about -100 ° C., nitrogen atmosphere), dissolving it in water, and using a potentiometric titrator ("COM-1600 ( model number)”, manufactured by Hiranuma Sangyo Co., Ltd.).
  • COM-1600 model number
  • Example 1 Prepare low-grade lithium carbonate containing the elements shown in Table 1, prepared according to the following (Preparation of low-grade lithium carbonate), and hydroxylate using the lithium compound production apparatus shown in FIG. Lithium and lithium carbonate were produced. The purity of the obtained lithium hydroxide was 99.9%, and extremely high-purity lithium hydroxide was obtained. The operation of each step in each device and the like in the lithium compound manufacturing apparatus was carried out as follows.
  • Low-grade lithium carbonate which is a starting material, was prepared by adding metals such as Ca and Mg as impurity components to lithium carbonate (commercial product) assuming that it was derived from brackish water.
  • the purity of lithium carbonate in the low-grade lithium carbonate was 90.7% by mass.
  • reaction tank 1 and oxalic acid treatment In the reaction tank 1, the above aqueous solution containing low-grade lithium carbonate (lithium carbonate content: 99.0 mol%) was mixed with acetic acid so that the molar amount of acetic acid was 1.1 times that of lithium carbonate, and 4.72 mol/L A lithium acetate solution (aqueous solution A) was prepared. The Ca content contained in the lithium acetate solution (aqueous solution A) was 0.90 mol%. Then, a white solid (separated solid 4) produced by adding 1.1 times the molar amount of oxalic acid to the Ca concentration in the aqueous solution A was separated by filtration (solid-liquid separation 4).
  • reaction tank 2 The mixing ratio of potassium hydroxide and lithium acetate was adjusted as follows, depending on the molar ratio of potassium to lithium (K/Li metal molar ratio). While stirring a 50% by mass aqueous solution of potassium hydroxide (aqueous solution B, mother liquor) supplied from the electrochemical device at a stirring speed of 30 rpm, the lithium acetate solution (separated liquid 4) obtained in solid-liquid separation 4 was After dropping until the molar ratio of potassium to lithium (K/Li metal molar ratio) reached 1.5, stirring was continued for 24 hours to effect crystallization and aging of lithium hydroxide crystals.
  • aqueous solution B mother liquor
  • Re-dissolution tank and solid-liquid separation 2 In the re-dissolving tank, 70 ml of pure water was added to 30 g of lithium hydroxide (separated solid 1) obtained by the above crystallization and aging to re-dissolve to prepare 100 g of an aqueous lithium hydroxide solution. Next, hexafluorosilicic acid was added to the prepared solution (aqueous solution D) at a molar ratio of 0.5 times the potassium in the solution, and after stirring for 2 hours, the product (white solid) was separated by filtration (solid Liquid separation 2) was carried out. The purified lithium hydroxide aqueous solution was allowed to stand overnight at about 10° C. for cooling, and the cooled solution was filtered (solid-liquid separation 3) to obtain lithium hydroxide (white crystals).
  • an electrochemical device As an electrochemical apparatus, an iridium-coated titanium plate was used as an oxygen generating electrode, a titanium plate, a stainless steel plate as a cathode plate, and an AHO film (manufactured by Asahi Glass Co., Ltd.) as an anion exchange film. A part of the lithium acetate solution (aqueous solution A) obtained in the reaction tank 1 is supplied to the anode side, and the separated liquid 1 obtained by the reaction tank 2 (crystallization) and solid-liquid separation 1 is supplied to the cathode side. Then, an electrochemical reaction was carried out at a constant current of 1A.
  • the diaphragm layer capacity in the electrochemical device is 200 ml, and the effective electrode area is 4.0 ⁇ 3.0 cm 2 .
  • a mixed gas mainly containing carbon dioxide (CO 2 ) generated in the reaction tank 1 is added to the separated liquid 2 (aqueous lithium hydroxide solution) obtained by the solid-liquid separation 2, and the molar ratio of carbon dioxide (CO 2 ) is After blowing for 30 minutes so as to be 0.5 times the lithium hydroxide in the separated liquid 2, the solution is filtered (solid-liquid separation 5), and white crystals (lithium carbonate) are separated as a solid 5.
  • the obtained lithium carbonate had a purity of 99.5% and a yield of 30%.
  • Example 2 In Example 1, the crystallization in the reaction vessel 2 was carried out except that the lithium acetate solution (separated liquid 4) was added dropwise until the molar ratio of potassium to lithium (K/Li metal molar ratio) was 2.5. Lithium carbonate was obtained in the same manner as in 1. The obtained lithium carbonate had a purity of 99.5% and a yield of 45%.
  • Example 3 Using the apparatus for producing a lithium compound shown in FIG. 3, the lithium hydroxide aqueous solution obtained in the reaction vessel 2 was supplied to the lithium ion separator as follows. In Example 1, in reaction tank 2 containing 200 mL of the lithium acetate battery material chamber solution (separated liquid 4) obtained in solid-liquid separation 4, 5 M sodium hydroxide aqueous solution (aqueous solution B, mother liquor) was added at a stirring speed of 30 rpm. It was added dropwise until the pH reached 13 while stirring at , to obtain an aqueous lithium hydroxide solution containing lithium ions.
  • the lithium hydroxide aqueous solution obtained in the reaction vessel 2 was supplied to the lithium ion separator as follows. In Example 1, in reaction tank 2 containing 200 mL of the lithium acetate battery material chamber solution (separated liquid 4) obtained in solid-liquid separation 4, 5 M sodium hydroxide aqueous solution (aqueous solution B, mother liquor) was added at a stirring speed of 30 rpm.
  • the obtained aqueous solution C is put into the raw solution tank as a raw solution, and a 0.1 M lithium hydroxide aqueous solution is put in the recovery liquid tank as a recovery liquid. recovered. Evaporative crystallization was performed on the recovered liquid in which Li ions were recovered after voltage application for 240 hours. X-ray diffraction (XRD) measurement of the precipitated solid content confirmed that only lithium hydroxide monohydrate was produced (purity: 99.9%).
  • Example 4 In Example 3, an electrochemical device equipped with a cation exchange membrane was used, 200 mL of the Li ion-removed aqueous solution after recovering lithium ions was placed in the anode tank of the electrochemical device, and 200 mL of a 0.1 M sodium hydroxide aqueous solution was placed in the cathode tank. was placed in a constant current state of 1 A for 24 hours of electrochemical reaction. The concentrations of sodium in the aqueous sodium hydroxide solution introduced into the cathode side before and after the electrochemical reaction were 0.1M and 3.5M, respectively.
  • the lithium compound manufacturing apparatus used in Example 4 is shown in FIG.
  • Example 5 For the lithium formate solution obtained in Preparation Example 1, the salt obtained in the same manner as in Reference Example 1 above was subjected to solid-liquid separation by filtration, and the separated liquid was evaporated to dryness. ) Measurement confirmed that lithium hydroxide monohydrate was produced. Therefore, even when formic acid is used as the organic acid, it is considered that high-purity lithium hydroxide can be obtained similarly to acetic acid.
  • a high-purity lithium compound can be efficiently produced from low-grade lithium carbonate containing impurities such as brackish water, according to the lithium compound production method and production apparatus of the present embodiment.
  • impurities such as brackish water
  • formic acid, oxalic acid, and citric acid, as well as acetic acid can efficiently produce a high-purity lithium compound as organic acids.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Organic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Metallurgy (AREA)
  • Water Supply & Treatment (AREA)
  • Urology & Nephrology (AREA)
  • Health & Medical Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
PCT/JP2022/017005 2021-04-01 2022-04-01 リチウム化合物の製造方法及びリチウム化合物の製造装置 Ceased WO2022211128A1 (ja)

Priority Applications (3)

Application Number Priority Date Filing Date Title
US18/553,099 US20240182316A1 (en) 2021-04-01 2022-04-01 Method for producing lithium compound and apparatus for producing lithium compound
CN202280025918.4A CN117098728A (zh) 2021-04-01 2022-04-01 锂化合物的制造方法及锂化合物的制造装置
JP2023511762A JP7781147B2 (ja) 2021-04-01 2022-04-01 リチウム化合物の製造方法及びリチウム化合物の製造装置

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2021-063165 2021-04-01
JP2021063165 2021-04-01

Publications (1)

Publication Number Publication Date
WO2022211128A1 true WO2022211128A1 (ja) 2022-10-06

Family

ID=83459667

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2022/017005 Ceased WO2022211128A1 (ja) 2021-04-01 2022-04-01 リチウム化合物の製造方法及びリチウム化合物の製造装置

Country Status (4)

Country Link
US (1) US20240182316A1 (https=)
JP (1) JP7781147B2 (https=)
CN (1) CN117098728A (https=)
WO (1) WO2022211128A1 (https=)

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH07299333A (ja) * 1994-05-10 1995-11-14 Asahi Glass Co Ltd 有機酸の再生方法
JP2011518257A (ja) * 2008-04-22 2011-06-23 ケメタル・フット・コーポレイション 高純度水酸化リチウムと塩酸とを製造する方法
US20130272933A1 (en) * 2010-06-28 2013-10-17 Korea Resources Corporation Method for producing high-purity lithium carbonate
JP2018520872A (ja) * 2015-06-11 2018-08-02 ビーエル テクノロジーズ、インコーポレイテッド バイポーラ電気透析方法及びシステム
US20190031527A1 (en) * 2017-07-28 2019-01-31 Nano One Materials Corp. Process For The Manufacture Of Lithium Metal Oxide Cathode Materials
JP2019131448A (ja) * 2018-02-02 2019-08-08 山本　秀樹 水酸化リチウムの製造方法

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB600182A (en) * 1942-03-27 1948-04-02 Walter Henry Groombridge Production of acetic acid and other lower fatty acids from their salts
JP5138822B1 (ja) * 2012-02-23 2013-02-06 株式会社アストム 高純度水酸化リチウムの製造方法
CN106187732A (zh) * 2016-07-14 2016-12-07 合肥工业大学 利用电渗析装置与双极膜电渗析装置处理醋酸钠废渣的集成装置与方法

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH07299333A (ja) * 1994-05-10 1995-11-14 Asahi Glass Co Ltd 有機酸の再生方法
JP2011518257A (ja) * 2008-04-22 2011-06-23 ケメタル・フット・コーポレイション 高純度水酸化リチウムと塩酸とを製造する方法
US20130272933A1 (en) * 2010-06-28 2013-10-17 Korea Resources Corporation Method for producing high-purity lithium carbonate
JP2018520872A (ja) * 2015-06-11 2018-08-02 ビーエル テクノロジーズ、インコーポレイテッド バイポーラ電気透析方法及びシステム
US20190031527A1 (en) * 2017-07-28 2019-01-31 Nano One Materials Corp. Process For The Manufacture Of Lithium Metal Oxide Cathode Materials
JP2019131448A (ja) * 2018-02-02 2019-08-08 山本　秀樹 水酸化リチウムの製造方法

Also Published As

Publication number Publication date
CN117098728A (zh) 2023-11-21
US20240182316A1 (en) 2024-06-06
JP7781147B2 (ja) 2025-12-05
JPWO2022211128A1 (https=) 2022-10-06

Similar Documents

Publication Publication Date Title
US12252409B2 (en) Preparation of lithium carbonate from lithium chloride containing brines
CA2985579C (en) Method of producing lithium carbonate from lithium chloride with gas-liquid-solid separator
EP3132491B1 (en) Methods for regeneration of aqueous alkaline solution
US9034295B2 (en) Preparation of lithium carbonate from lithium chloride containing brines
CN103097586B (zh) 通过电解从含锂溶液中提取高纯度锂的方法
US11174532B1 (en) Processes for producing lithium compounds using reverse osmosis
JPS62161973A (ja) 高純度炭酸リチウムの製造方法
JP7806991B2 (ja) 水酸化リチウムの製造方法
US20230406718A1 (en) Method for producing lithium hydroxide
JP7781147B2 (ja) リチウム化合物の製造方法及びリチウム化合物の製造装置
JP7705925B2 (ja) 水酸化リチウムの製造方法
US20260062305A1 (en) Lithium production coupled to acid and base production
JP2025530099A (ja) 水素および固体水酸化リチウムの生産

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 22781335

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 2023511762

Country of ref document: JP

Kind code of ref document: A

WWE Wipo information: entry into national phase

Ref document number: 202280025918.4

Country of ref document: CN

WWE Wipo information: entry into national phase

Ref document number: 18553099

Country of ref document: US

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 22781335

Country of ref document: EP

Kind code of ref document: A1