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KR-20260065871-A - Lithium recovery device, multi-chamber lithium recovery device and lithium recovery method

KR20260065871AKR 20260065871 AKR20260065871 AKR 20260065871AKR-20260065871-A

Abstract

In the lithium recovery device (1), the treatment tank (7) is divided into three chambers (11, 12, 13) in order by an ion-conducting membrane (31) and a lithium-ion conductive electrolyte membrane (2), and a power source (5) is connected between the electrodes (41, 42) installed in each of the chambers (11, 13) at both ends, with the first electrode chamber (11) side being positive (+), and water (S1) is contained in the first electrode chamber (11), a non-aqueous solution of Li (FS) is contained in the Li supply chamber (12), and an aqueous solution for Li recovery (RS) is contained in the Li recovery chamber (13). When voltage is applied by the power source (5), H + from water (S1) passes through the ion-conducting membrane (31) and moves to the Li-containing non-aqueous solution (FS), and in the Li-containing non-aqueous solution (FS) supplied with H + , Li + moves into the lithium-ion conductive electrolyte membrane (2) to maintain charge equilibrium, and Li + in the lithium-ion conductive electrolyte membrane (2) moves to the Li recovery solution (RS).

Inventors

  • 사사키 카즈야
  • 신무라 키요토

Assignees

  • 히로사키 유니버시티

Dates

Publication Date
20260511
Application Date
20240927
Priority Date
20230929

Claims (18)

  1. A treatment tank partitioned in the order of the first room, the second room, and the third room, A lithium-ion conductive electrolyte membrane that partitions the above-mentioned treatment tank into the above-mentioned first chamber and the above-mentioned second chamber, A first ion-conducting membrane that divides the above-mentioned treatment tank into the above-mentioned second chamber and the above-mentioned third chamber, The first electrode installed in the third chamber above, A second electrode installed in the chamber at the opposite end of the partitioned third chamber of the above-mentioned treatment tank, and A power source is provided with a positive electrode connected to the first electrode and a negative electrode connected to the second electrode, and A lithium recovery device for transferring lithium ions from a non-aqueous solution containing lithium ions contained in the second chamber to water or an organic solvent contained in the first chamber, The first ion-conducting membrane conducts at least one type of cation other than lithium ions, or at least one type of anion that is water-soluble and contained in the non-aqueous solution, and A lithium recovery device characterized by the fact that water is contained in the third chamber.
  2. In paragraph 1, The above-mentioned treatment tank is divided into the first chamber and the fourth chamber, and a second ion-conducting membrane that does not conduct lithium ions is additionally provided, The second electrode is installed in the fourth chamber, and A lithium recovery device in which water is contained in the above-mentioned fourth chamber.
  3. A treatment tank partitioned in the order of the second room, the first room, and the third room, A lithium-ion conductive electrolyte membrane that partitions the above-mentioned treatment tank into the above-mentioned first chamber and the above-mentioned second chamber, The above treatment tank is partitioned into the above first chamber and the above third chamber, and a second ion-conducting membrane that does not conduct lithium ions, The first electrode installed in the second chamber above, A second electrode installed in the third chamber, and A power source is provided with a positive electrode connected to the first electrode and a negative electrode connected to the second electrode, and A lithium recovery device for transferring lithium ions from a non-aqueous solution containing lithium ions contained in the second chamber to water or an organic solvent contained in the first chamber, Water is contained in the aforementioned third chamber, and A lithium recovery device characterized by additionally accommodating water in the second chamber.
  4. In paragraph 2 or 3, An organic solvent is contained in the first chamber above, and In the chamber where the second electrode is installed in the above treatment tank, an aqueous solution in which an anion soluble in the organic solvent is dissolved is contained, and The above second ion-conducting membrane is a lithium recovery device that conducts the above anions.
  5. In paragraph 1, An organic solvent is contained in the first chamber above, and The above power source is a lithium recovery device that applies a voltage such that the potential of the second electrode becomes lower than or equal to the lithium ion reduction potential.
  6. In any one of paragraphs 1 through 4, The above power supply is formed by connecting the first power supply and the second power supply in series in order from the positive (+) side, and A third electrode is additionally provided that is connected to the negative electrode of the first power source, is spaced apart from the second electrode, and is also arranged to be in contact with or facing the first actual surface of the lithium-ion conductive electrolyte membrane. A lithium recovery device in which water or an organic solvent in which anions are dissolved is contained in the first chamber.
  7. A lithium recovery method for moving lithium ions contained in a non-aqueous solution contained in a second chamber to water or an organic solvent contained in the first chamber in a treatment tank partitioned into a first chamber and a second chamber by a lithium ion conductive electrolyte membrane, wherein The above treatment tank is further divided into the second and third chambers by a first ion-conducting membrane that conducts at least one type of cation other than lithium ion, or at least one type of anion that is water-soluble and contained in the above non-aqueous solution, and water is contained in the third chamber. A lithium recovery method characterized by applying a voltage from a power source connected with the first electrode as positive (+) between a first electrode installed in the third chamber and a second electrode installed in the chamber at the opposite end of the third chamber partitioned in the processing tank.
  8. A lithium recovery method for moving lithium ions contained in a non-aqueous solution contained in a second chamber to water or an organic solvent contained in the first chamber in a treatment tank partitioned into a first chamber and a second chamber by a lithium ion conductive electrolyte membrane, wherein Water is additionally contained in the second chamber mentioned above, and A lithium recovery method characterized by applying a voltage from a power source connected with the first electrode as positive (+) between a first electrode installed in the second chamber and a second electrode installed in the chamber at the opposite end of the second chamber partitioned in the processing tank.
  9. In Article 7 or Article 8, The above treatment tank is further divided into the first and fourth chambers by a second ion-conducting membrane that does not conduct lithium ions, and The second electrode is installed in the fourth chamber, and A lithium recovery method in which water is contained in the above-mentioned fourth chamber.
  10. In Paragraph 9, An organic solvent is contained in the first chamber above, and In the chamber where the second electrode is installed in the above treatment tank, an aqueous solution in which an anion soluble in the organic solvent is dissolved is contained, and The above second ion-conducting membrane is a lithium recovery method that conducts the above anions.
  11. In Article 7 or Article 8, An organic solvent is contained in the first chamber above, and A lithium recovery method in which the above power source applies a voltage such that the potential of the second electrode becomes lower than or equal to the lithium ion reduction potential.
  12. In any one of paragraphs 7 through 10, The first chamber above contains water or an organic solvent in which anions are dissolved, and The above power supply is formed by connecting the first power supply and the second power supply in series in order from the positive (+) side, and A lithium recovery method in which a third electrode is connected to the negative electrode of the first power source, the third electrode is spaced apart from the second electrode and is also positioned to be in contact with or facing the first actual surface of the lithium-ion conductive electrolyte membrane.
  13. 2 or more lithium-ion conductive electrolyte membranes, A first ion-conducting membrane disposed on one end of the lithium-ion conductive electrolyte membrane disposed first from the end side, A second ion-conducting membrane disposed between the above lithium-ion conductive electrolyte membranes and not conducting lithium ions, A treatment tank partitioned into five or more chambers by the first ion-conducting membrane, the lithium-ion conductive electrolyte membrane, and the second ion-conducting membrane, A first electrode installed in a chamber at one end partitioned in the above-mentioned processing tank and a second electrode installed in a chamber at the other end, and A power source is provided with a positive electrode connected to the first electrode and a negative electrode connected to the second electrode, and Water is contained in the aforementioned partitioned chambers in the above treatment tank, and A multi-chamber lithium recovery device for transferring lithium ions from a non-aqueous solution containing lithium ions contained in one end of two adjacent chambers partitioned by the lithium ion conductive electrolyte membrane to water contained in the other end.
  14. In Paragraph 13, The second ion-conducting membrane is additionally provided to partition the treatment tank between the lithium-ion conductive electrolyte membrane positioned as the first from the other end and the second electrode, and A multi-chambered lithium recovery device in which water is contained in the chamber at the other end, partitioned by the second ion-conducting membrane in the above-mentioned treatment tank.
  15. In paragraph 13 or 14, The above power supply is formed by connecting the first power supply and the second power supply in series in order from the positive (+) side, and A multi-chambered lithium recovery device further comprising a third electrode connected to the negative electrode of the first power source, spaced apart from the second electrode, and positioned to contact or face the surface of the other end of the lithium-ion conductive electrolyte membrane positioned first from the other end.
  16. A lithium recovery method for transferring lithium ions from a non-aqueous solution containing lithium ions contained in one of two adjacent chambers partitioned by lithium ion-conducting electrolyte membranes to water contained in the other chamber, in a treatment tank partitioned into five or more chambers by ion-conducting membranes and lithium ion-conducting electrolyte membranes alternately arranged from one end thereof. The ion-conducting membrane disposed between the above lithium-ion conductive electrolyte membranes does not conduct lithium ions, and Water is contained in the aforementioned partitioned chambers in the above treatment tank, and A power source connected with the first electrode as positive (+) is applied between the first electrode installed in the partitioned chamber of the above-mentioned processing tank and the second electrode installed in the chamber of the other end, and A lithium recovery method characterized by transferring lithium ions from a non-aqueous solution containing lithium ions contained in one end of the two adjacent chambers to water contained in the other end.
  17. In Paragraph 16, The above treatment tank is partitioned by an ion-conducting membrane that does not conduct lithium ions, which is disposed between the lithium-ion conductive electrolyte membrane disposed first from the other end and the second electrode, and A lithium recovery method in which water is contained in the chamber at the other end, partitioned by the ion-conducting membrane in the above-mentioned treatment tank.
  18. In paragraph 16 or 17, The above power supply is formed by connecting the first power supply and the second power supply in series in order from the positive (+) side, and A lithium recovery method in which a third electrode is connected to the negative electrode of the first power source, the third electrode is spaced apart from the second electrode and is also positioned to contact or face the surface of the other end of the lithium-ion conductive electrolyte membrane, which is the first from the other end.

Description

Lithium recovery device, multi-chamber lithium recovery device and lithium recovery method The present invention relates to a lithium recovery apparatus and a lithium recovery method for selectively recovering lithium ions from a non-aqueous solution. Lithium (Li) is a resource in high demand as a raw material for lithium-ion rechargeable batteries and fuel for nuclear fusion reactors, and there is a demand for extraction methods that can be supplied stably and are also more inexpensive. Stable sources of Li include seawater in which it is dissolved in the form of cations Li + . Furthermore, since the cathode of lithium-ion rechargeable batteries mainly contains Li as lithium cobaltate ( LiCoO2 ), there is a demand for inexpensive recovery technologies from batteries that have been discarded due to battery lifespan issues (spent batteries). While adsorption methods have conventionally been applied for Li recovery from seawater, etc., recovery by electrodialysis using an electrolyte membrane having lithium-ion conductivity is being developed as a method with superior selectivity (e.g., Patent Documents 1 to 3, Non-patent Document 1). A method for recovering Li by electrodialysis as described in Patent Document 1, etc., is described with reference to FIG. 25. A lithium recovery device (101) divides a treatment tank (107) into a Li supply room (112) and a Li recovery room (113) by a lithium-ion conductive electrolyte membrane (hereinafter, electrolyte membrane) (2), and is configured such that a power source (105) is connected between an electrode (141) in the Li supply room (112) and an electrode (142) in the Li recovery room (113), with the electrode (141) serving as the positive electrode. A Li-containing aqueous solution (SW), such as seawater, is introduced into the Li supply room (112) as a source of Li, and an aqueous solution for Li recovery (RS), such as pure water, is introduced into the Li recovery room (113). In the Li-containing aqueous solution (SW), lithium ions (Li + ) and other metal ions (Mn + ), hydrogen ions (H + ), hydroxide ions ( OH- ), and other anions, such as chloride ions ( Cl- ) or sulfate ions (SO42- ) , are dissolved. When voltage is applied by the power source (105), in the Li-containing aqueous solution (SW) of the Li supply chamber (112), the reaction of Formula 1 below occurs near the electrode (141) to produce oxygen ( O2 ), and the reaction of Formula 2 below occurs on the surface of the electrolyte membrane (2). Additionally, if the Li-containing aqueous solution (SW) contains Cl- , additional chlorine ( Cl2 ) is produced near the electrode (141). Meanwhile, in the Li recovery aqueous solution (RS) of the Li recovery chamber (113), the reaction of Formula 3 below occurs on the surface (back side) of the electrolyte membrane (2), and the reaction of Formula 4 below occurs near the electrode (142) to produce hydrogen ( H2 ). In addition, in each equation, the lithium ion (Li + ) contained in the electrolyte membrane (2) (electrolyte) is represented as Li + (electrolyte), and other ions (Li + , H + , OH- ) are represented as being dissolved in the aqueous solution. Equation 2 below represents the reaction in which Li + in the solution moves into the electrolyte membrane (2), and Equation 3 below represents the reaction in which Li + in the electrolyte membrane (2) moves into the solution. As a result, due to the electrochemical potential difference of Li + contained in the Li-containing aqueous solution (SW), the electrolyte membrane (2), and the Li recovery aqueous solution (RS), Li + in the Li-containing aqueous solution (SW) passes through the electrolyte membrane (2) and moves to the Li recovery aqueous solution (RS). Since the size of the lattice defect sites in the electrolyte membrane (2) is small, it does not allow metal ions Mn +, such as Na + and Ca2 + , which have a larger diameter than Li + to pass through. Accordingly, Li + is selectively transferred from the Li-containing aqueous solution (SW) to the Li recovery aqueous solution (RS), and an aqueous solution of Li + (aqueous solution of lithium hydroxide) is obtained in the Li recovery chamber (113). [Fig. 1] This is a schematic diagram illustrating the configuration of a lithium recovery device according to a first embodiment of the present invention. [Fig. 2] This is a schematic diagram of the lithium recovery apparatus shown in Fig. 1, illustrating a lithium recovery method according to a first embodiment of the present invention. [Fig. 3] This is a schematic diagram illustrating the configuration of a lithium recovery device and a lithium recovery method according to a modified example of the first embodiment of the present invention. [Fig. 4] This is a schematic diagram illustrating the configuration of a lithium recovery device and a lithium recovery method according to a modified example of the first embodiment of the present invention. [Fig. 5] This is a schematic diagram illustrating the configuration of