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CN-117839650-B - Lithium ion sieve adsorbent, preparation method and application thereof

CN117839650BCN 117839650 BCN117839650 BCN 117839650BCN-117839650-B

Abstract

The invention belongs to the technical field of lithium extraction in salt lakes, and particularly relates to a lithium ion sieve adsorbent, a preparation method and application thereof. The polyion liquid with phosphate groups is formed on the manganese ion sieve material, can be used as an adhesive, can play a role in extracting lithium, avoids the problem of reduced lithium extraction performance caused by the fact that the adhesive covers the adsorption active sites of the ion sieve, and can improve the adsorption capacity of lithium while reducing the dissolution loss rate of manganese.

Inventors

  • YU HAIJUN
  • XIE YINGHAO
  • LI AIXIA
  • LI CHANGDONG

Assignees

  • 广东邦普循环科技有限公司
  • 湖南邦普循环科技有限公司

Dates

Publication Date
20260505
Application Date
20240219

Claims (20)

  1. 1. A lithium ion sieve adsorbent, comprising a manganese ion sieve material, wherein a polyion liquid is combined on the manganese ion sieve material; wherein the anions in the polyionic liquid carry p=o groups; the lithium ion sieve adsorbent is prepared by polymerizing a vinyl modified adsorbent and an ionic liquid monomer, wherein the ionic liquid monomer contains phosphate groups and vinyl groups, the vinyl modified adsorbent comprises a manganese ion sieve material, and a silane coupling agent containing vinyl groups is combined on the manganese ion sieve material.
  2. 2. The lithium ion sieve adsorbent according to claim 1, wherein the ionic liquid monomer is selected from at least one of dibutyl 1-vinyl-3-ethylimidazole phosphate and diethyl 1-vinyl-3-ethylimidazole phosphate.
  3. 3. The lithium ion sieve adsorbent according to claim 1, wherein the manganese-based ion sieve material is selected from at least one of MnO 2 ·0.5H 2 O、λ-MnO 2 and MnO 2 ·0.3H 2 O.
  4. 4. The lithium ion sieve adsorbent according to claim 1, wherein the mass ratio of phosphoric acid groups in the lithium ion sieve adsorbent is 15% -35%.
  5. 5. The lithium ion sieve adsorbent of claim 1, wherein the silane coupling agent is selected from at least one of vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane, vinyltriisopropenyloxysilane, methylvinyldimethoxysilane, methylvinyldiethoxysilane, and tetramethyldivinyl disiloxane.
  6. 6. A method for preparing the lithium ion sieve adsorbent according to any one of claims 1 to 5, comprising mixing and reacting a vinyl-modified adsorbent with an ionic liquid monomer containing a phosphate group and a vinyl group, and polymerizing the ionic liquid monomer; Wherein the vinyl modified adsorbent comprises a manganese ion sieve material, and a silane coupling agent containing vinyl is combined on the manganese ion sieve material.
  7. 7. The method according to claim 6, wherein the method comprises modifying the manganese-based ion sieve material with a silane coupling agent containing vinyl groups to obtain a vinyl-modified adsorbent, and mixing the vinyl-modified adsorbent with the ionic liquid monomer for reaction.
  8. 8. The method according to claim 7, wherein the vinyl-modified adsorbent is prepared by mixing the manganese-based ion sieve material, the silane coupling agent and a solvent and reacting at 40 to 85 ℃ for 12 to 24 hours.
  9. 9. The method according to claim 8, wherein a silane coupling agent and a solvent are mixed to obtain a silane coupling agent solution, and the manganese-based ion sieve material and the silane coupling agent solution are mixed, and the concentration of the silane coupling agent solution is 0.5wt% to 10wt%.
  10. 10. The preparation method according to claim 8, wherein the mass ratio of the manganese-based ion sieve material to the silane coupling agent is 1 (0.4-0.8).
  11. 11. The method according to claim 8, wherein the manganese-based ion sieve material has a particle size of 800 mesh to 1000 mesh.
  12. 12. The preparation method according to claim 8, wherein the solvent is a mixed solvent of an organic solvent and water, and the mass fraction of water in the mixed solvent is 5% -15%.
  13. 13. The method according to claim 12, wherein the organic solvent is at least one selected from the group consisting of methanol, ethanol, isopropanol, dimethyl sulfoxide and N-methylpyrrolidone.
  14. 14. The method according to claim 8, wherein after the reaction between the manganese ion sieve material and the silane coupling agent is completed, solid-liquid separation is performed to obtain a solid material, and the solid material is washed and dried to obtain the vinyl-modified adsorbent.
  15. 15. The method according to claim 7, wherein the vinyl-modified adsorbent, the solvent, the ionic liquid monomer, the crosslinking agent, and the initiator are mixed and polymerized at 65 ℃ to 75 ℃ for 6 hours to 24 hours.
  16. 16. The method according to claim 15, wherein the mass ratio of the vinyl-modified adsorbent to the ionic liquid monomer is (5-15): 1.
  17. 17. The method according to claim 15, wherein the crosslinking agent is at least one selected from the group consisting of ethylene glycol dimethacrylate and divinylbenzene, and the mass ratio of the crosslinking agent to the ionic liquid monomer is (10-15): 100.
  18. 18. The method according to claim 15, wherein the initiator is at least one selected from the group consisting of azobisisobutyronitrile and benzoyl peroxide, and the mass ratio of the initiator to the ionic liquid monomer is (1.0-1.5): 100.
  19. 19. The preparation method according to claim 15, wherein the vinyl-modified adsorbent and the solvent are mixed, then mixed with the ionic liquid monomer, the crosslinking agent and the initiator, and inert gas is introduced for 30min to 60min, and then polymerization is performed under closed conditions.
  20. 20. The method according to claim 19, wherein the solvent is at least one selected from the group consisting of N, N-dimethylformamide and N-methylpyrrolidone, and the amount of the solvent is 1mL to 3mL per gram of the vinyl-modified adsorbent.

Description

Lithium ion sieve adsorbent, preparation method and application thereof Technical Field The invention belongs to the technical field of lithium extraction in salt lakes, and particularly relates to a lithium ion sieve adsorbent, a preparation method and application thereof. Background Along with the rapid development of electronic products and new energy automobiles, the demand of lithium resources is increased year by year, but the supply of lithium resources is limited, and the contradiction between the supply and the demand of lithium resources promotes the efficient development and extraction of the lithium resources to become a research hot spot. Currently, lithium resources in salt lake brine are richer than ore lithium resources, and the defects of high energy consumption and high pollution commonly exist in the process of extracting lithium from the ore, so that the process of extracting lithium from the salt lake brine gradually becomes a main way for obtaining the lithium resources. At present, the development and utilization of salt lake brine lithium resources mainly use methods such as ion exchange and adsorption, extraction, nanofiltration, selective electrodialysis, electrochemistry and the like. The adsorbent method is a lithium extraction method which can realize selective adsorption of lithium ions by using the adsorbent, and can be desorbed through acid washing after the adsorption of lithium ions, so that the lithium ions are separated from other ions, and the method has the advantages of easy regeneration, simple operation, high recovery rate and the like, and is one of the very promising lithium extraction methods. The lithium extraction adsorbent of the salt lake mainly comprises an aluminum adsorbent, a manganese adsorbent, a titanium adsorbent and the like. The manganese ion sieves prepared at present are all in powder form, have insufficient permeability and poor fluidity, and generally have the problems of high dissolution loss rate, low lithium recovery rate and reduced adsorption amount in the elution process. At present, the ion sieve shape is improved by mainly adopting a granulating method, a film-forming method, a foaming method, a nanofiber film method, a membrane electrode method, a magnetizing method and other forming modes. Among them, granulation is the most commonly used method of forming an ion sieve. Granulation is usually carried out by directly mixing and shaping a precursor with a binder, or cross-linking the precursor in a polymer solution to obtain a granular ion sieve adsorbent. However, the adsorption amount of the granulated adsorbent applied to the actual salt lake brine is reduced because the adsorption sites of the adsorbent are blocked by the binder or the polymer, so that the active sites for adsorbing lithium are reduced. Therefore, there is a need to improve the preparation process of the manganese-series lithium ion sieve adsorbent so as to improve the stability of the ion sieve adsorbent and improve the adsorption capacity of lithium while reducing the dissolution loss rate of manganese. In view of this, the present invention has been made. Disclosure of Invention The invention aims to provide a lithium ion sieve adsorbent, a preparation method and application thereof, and aims to reduce the dissolution loss rate of manganese and improve the adsorption capacity of lithium. In order to achieve the above object of the present invention, the following technical solutions may be adopted: In a first aspect, the present invention provides a solution comprising a lithium ion sieve adsorbent comprising a manganese-based ion sieve material having a polyionic liquid bound thereto; Wherein the anions in the polyionic liquid carry p=o groups. In some embodiments of the invention, the lithium ion sieve adsorbent is polymerized by vinyl modified adsorbent and ionic liquid monomer, wherein the ionic liquid monomer contains phosphate groups and vinyl groups; preferably, the ionic liquid monomer is selected from at least one of dibutyl 1-vinyl-3-ethylimidazole phosphate and diethyl 1-vinyl-3-ethylimidazole phosphate; Preferably, the manganese-based ion sieve material is selected from at least one of MnO 2·0.5H2O、λ-MnO2 and MnO 2·0.3H2 O; preferably, in the lithium ion sieve adsorbent, the mass ratio of the phosphoric acid groups is 15% -35%; Preferably, the silane coupling agent is selected from at least one of vinyltrimethoxysilane, vinyltriethoxysilane, 3-methacryloylpropyl trimethoxysilane, vinyltriacetoxy silane, vinyltriisopropenyloxy silane, methylvinyldimethoxy silane, methylvinyldiethoxy silane, methacryloyloxy trimethoxysilane, methacryloyloxy triethoxysilane, and tetramethyl divinyl disiloxane. In a second aspect, the invention also provides a method for preparing the lithium ion sieve adsorbent, which comprises the steps of mixing and reacting the vinyl modified adsorbent with an ionic liquid monomer containing phosphate groups and vinyl groups to polymeri