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CN-121992200-A - Method for selectively extracting lithium and regenerating waste ternary positive electrode material

CN121992200ACN 121992200 ACN121992200 ACN 121992200ACN-121992200-A

Abstract

The invention belongs to the technical field of battery waste recovery, and particularly discloses a method for selectively extracting lithium and regenerating a waste ternary cathode material. The method comprises the steps of placing waste ternary cathode material powder in a reactor for high-energy field in-situ lattice reconstruction treatment to obtain treated powder, adding the powder into a solvent for leaching reaction, carrying out solid-liquid separation to obtain a lithium-rich solution and leaching residues, carrying out lithium precipitation treatment on the lithium-rich solution to obtain lithium carbonate precipitate, mixing the lithium carbonate precipitate with the leaching residues, and calcining to obtain the regenerated ternary cathode material. According to the invention, the in-situ lattice reconstruction of the waste ternary cathode material is realized from the aspects of an energy action mechanism and a crystal structure design, the separation of lithium and other metals is realized, the high-quality ternary cathode material is further regenerated, the utilization of waste resources is realized, and the whole process is green and environment-friendly and the cost is low.

Inventors

  • LIU XIAOJIAN
  • XIA PENG
  • HUANG JIANYI

Assignees

  • 江西三益再生资源利用有限公司

Dates

Publication Date
20260508
Application Date
20260225

Claims (10)

  1. 1. A method for selectively extracting lithium and regenerating waste ternary cathode materials is characterized by comprising the following steps: s1, placing waste ternary anode material powder into a reactor for high-energy field in-situ lattice reconstruction treatment to obtain treated powder; s2, adding the treated powder into a solvent, leaching, and carrying out solid-liquid separation to obtain a lithium-rich solution and leaching residues; s3, adding sodium carbonate into the lithium-rich solution, heating for reaction, performing solid-liquid separation to obtain lithium carbonate precipitate, mixing the lithium carbonate precipitate with leaching residues, and calcining to obtain a regenerated ternary anode material; The high-energy field in-situ lattice reconstruction treatment comprises microwave selective excitation reconstruction, low-temperature plasma selective etching and reconstruction or pulsed laser induced surface layer reconstruction.
  2. 2. The method for selectively extracting lithium and regenerating the waste ternary positive electrode material according to claim 1, wherein the waste ternary positive electrode material powder is waste positive electrode powder obtained by discharging, disassembling a positive electrode plate and stripping a current collector of a waste ternary lithium battery.
  3. 3. The method for selectively extracting lithium and regenerating the waste ternary cathode material according to claim 1, wherein the reactor used for microwave selective excitation and reconstruction is a pulse microwave sintering system.
  4. 4. The method for selectively extracting lithium and regenerating the waste ternary cathode material according to claim 3, wherein the treatment parameters of the pulse microwave sintering system are that the microwave power is 3-5 kW, the pulse mode is intermittent pulse, the microwave is turned on for 5-15 s, 2-5 s is turned off, the temperature is raised to 950-1050 ℃ for 2-3 min, the highest temperature is kept for 4-6 min, and 200-500 mL/min of oxygen is introduced during the treatment.
  5. 5. The method for selectively extracting lithium and regenerating the waste ternary cathode material according to claim 1, wherein the reactor used for the selective etching and the reconstruction of the low-temperature plasma is a low-temperature plasma treatment system.
  6. 6. The method for selectively extracting lithium and regenerating the waste ternary cathode material according to claim 5, wherein the treatment parameters of the low-temperature plasma treatment system are that a radio frequency power supply of 12-16 MHz is adopted, the power density is 0.5-1.5W/cm 2 , the pressure of a reaction chamber is 10-100 Pa, the treatment time is 5-30 min, the sample temperature is 25-75 ℃, and 50-200 sccm of oxygen is introduced.
  7. 7. The method for selectively extracting lithium and regenerating the waste ternary cathode material according to claim 1, wherein the reactor used for pulse laser induced surface layer reconstruction is a pulse laser processing system.
  8. 8. The method for selectively extracting lithium and regenerating the waste ternary positive electrode material according to claim 7 is characterized in that a laser with the wavelength of 1064nm or 532nm is used as a treatment parameter of the pulse laser treatment system, the pulse energy is 50-400 mJ/pulse, the pulse frequency is 10-40 kHz, the spot diameter at the powder flow focus of the waste ternary positive electrode material is 50-200 mu m, the scanning speed of a vibrating mirror is 100-200 mm/s, the carrier gas is compressed air or oxygen with the air flow rate of 10-50 m/s, the powder feeding rate is 5-50 g/min, the powder flow concentration is 10-100 g/m 3 , and the micro negative pressure of-10 to-50 Pa is treated in the treatment cavity.
  9. 9. The method for selectively extracting lithium and regenerating the waste ternary cathode material according to claim 1, wherein in the step S2, the leaching reaction has a liquid-solid mass ratio of (5-50): 1, and the solvent is water or a weak acid solution.
  10. 10. The method for selectively extracting and regenerating the waste ternary cathode material according to claim 1, wherein in the step S3, the mass ratio of the lithium carbonate precipitate to the leaching slag is 0.3-0.5): 1, and the calcination condition is that the treatment is carried out for 5-7 hours at 800-1000 ℃ in an air atmosphere.

Description

Method for selectively extracting lithium and regenerating waste ternary positive electrode material Technical Field The invention relates to the technical field of battery waste recovery, in particular to a method for selectively extracting lithium and regenerating waste ternary cathode materials. Background At present, valuable metals are recovered from waste lithium ion batteries, most of the valuable metals are dissolved out through a wet recovery process of reducing acid leaching, and then the valuable metals are recovered through methods such as precipitation, extraction, crystallization, resynthesis and the like, and the wet recovery process is mature and good in adaptability, but has the problems of long flow, low metal recovery rate, high auxiliary material cost and the like. In addition to recovery of valuable metals by dissolution methods, pyrometallurgy is also used in the industry to recover valuable metals. The pyrometallurgical process is to throw the waste material of the battery into a high temperature pyrolysis furnace under the high temperature condition, control the reaction in different temperature sections, heat the anode material of the waste lithium ion battery to generate a series of physical and chemical changes, and then realize the separation of valuable metal elements according to the property difference of the obtained product. The pyrogenic recovery method is the simplest process for treating the waste batteries, and has the advantages of large battery treatment capacity and high process automation degree, but the problems of difficult temperature control of a pyrolysis furnace, high safety risk, high impurity content in produced black powder, high alloy content in the black powder, difficult post-treatment and the like exist in the pyrogenic treatment process. Therefore, more new recovery methods of the anode materials of the waste lithium batteries are necessary to be explored, and efficient and selective recovery of valuable metals is realized. Disclosure of Invention The present invention aims to solve at least one of the technical problems existing in the prior art. Therefore, the invention provides a method for selectively extracting lithium from waste ternary cathode materials and regenerating the ternary cathode materials by using a high-energy process. According to the invention, the in-situ lattice reconstruction of the waste ternary cathode material is realized from the aspects of an energy action mechanism and a crystal structure design, the separation of lithium and other metals is realized by combining water leaching reaction, and the high-quality regenerated ternary cathode material is obtained by calcining the obtained high-purity lithium carbonate and leaching residues after specific treatment. The invention provides a method for selectively extracting lithium and regenerating waste ternary anode materials, which comprises the following steps: s1, placing waste ternary anode material powder into a reactor for high-energy field in-situ lattice reconstruction treatment to obtain treated powder; s2, adding the treated powder into a solvent, leaching, and carrying out solid-liquid separation to obtain a lithium-rich solution and leaching residues; s3, adding sodium carbonate into the lithium-rich solution, heating for reaction, performing solid-liquid separation to obtain lithium carbonate precipitate, mixing the lithium carbonate precipitate with leaching residues, and calcining to obtain a regenerated ternary anode material; The high-energy field in-situ lattice reconstruction treatment comprises microwave selective excitation reconstruction, low-temperature plasma selective etching and reconstruction or pulsed laser induced surface layer reconstruction. According to some embodiments of the invention, the waste ternary positive electrode material powder is waste positive electrode powder obtained by discharging, disassembling a positive electrode plate and stripping a current collector of a waste ternary lithium battery. According to some embodiments of the invention, the reactor used for microwave selective excitation and reconstruction is a pulse microwave sintering system, in particular an atmosphere protection box type pulse microwave sintering system. According to some embodiments of the invention, the treatment parameters of the pulse microwave sintering system are that the microwave power is 3-5 kW, the pulse mode is intermittent pulse, the microwave is turned on for 5-15 s, the microwave is turned off for 2-5 s, the temperature is raised to 950-1050 ℃ for 2-3 min, the highest temperature treatment is kept for 4-6 min, and 200-500 mL/min of oxygen is introduced during the treatment. According to some preferred embodiments of the invention, the maximum temperature is 1000±10 ℃. According to some embodiments of the invention, the oxygen is high-purity oxygen (purity is greater than or equal to 99.5%), and the flow rate of the oxygen is 250-350 mL/min. The i