Process for recovering transition metals from waste ternary lithium batteries

Abstract

The present application relates to the technical field of battery recycling, and particularly relates to a recovery process of transition metals in waste ternary lithium batteries. The present application comprises the following steps: preparing functionalized chitosan beads, preparing a leaching solution by acid leaching of waste ternary lithium battery positive material powder, treating the leaching solution with the functionalized chitosan beads, and preparing ternary precursor powder. The present application combines chitosan with 2-chloromethyl pyridine hydrochloride, and introduces an aminomethyl pyridine group on the chitosan through grafting reaction with 2-chloromethyl pyridine hydrochloride. The pyridine nitrogen atom and the amino nitrogen atom in the group can synergistically act to form a stable coordination structure with nickel ions, and have high selectivity for adsorbing nickel ions, so as to preferentially capture nickel in a mixed solution containing cobalt, manganese and lithium.

Description

Technical Field

[0001] This invention relates to the field of battery recycling technology, specifically to a process for recycling transition metals from waste ternary lithium batteries. Background Technology

[0002] With the rapid development of the new energy vehicle industry and the widespread use of portable electronic devices, the production and retirement volume of lithium-ion batteries have both experienced explosive growth. Among them, ternary lithium batteries dominate the power battery market due to their high energy density and good cycle performance. However, heavy metals and electrolytes from improperly disposed waste batteries can seep into soil and water, posing serious environmental risks. Currently, the mainstream recycling process for waste ternary lithium batteries is based on hydrometallurgy, which involves converting valuable metals in the cathode material into a mixed ionic solution through acid leaching, followed by steps such as impurity removal, separation, precipitation, or extraction to recover each metal element. The separation of nickel, cobalt, and manganese typically employs solvent extraction, utilizing the differences in the extraction capabilities of different extractants under specific pH conditions to achieve multi-stage countercurrent separation. However, this technical route suffers from a lengthy process. The separation of nickel and cobalt requires multi-stage extraction tanks, resulting in large equipment investment and a large footprint. Furthermore, the extractants are mostly organophosphorus compounds, leading to high consumption, and the operation process generates emulsification, third phase formation, and entrainment losses, increasing operational difficulty and cost.

[0003] In recent years, adsorption separation technology based on biomass materials has attracted widespread attention due to its advantages such as renewable raw materials, simple operation, and environmental friendliness. Chitosan is the second most abundant polysaccharide in nature, with abundant hydroxyl and amino groups on its molecular chain, which can serve as coordination sites for metal ions. However, natural chitosan has poor selectivity for transition metal ions such as nickel, cobalt, and manganese, making it difficult to specifically capture single ions from mixed solutions. Furthermore, it is prone to swelling and dissolution in acidic media, resulting in insufficient mechanical strength, which limits its direct application in strongly acidic leachates. To address these technical bottlenecks, this invention provides a process for recovering transition metals from waste ternary lithium batteries, offering a new technical solution for the efficient and green recovery of valuable metals from waste ternary lithium batteries. Summary of the Invention

[0004] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a recycling process for transition metals in waste ternary lithium batteries.

[0005] A process for recycling transition metals from spent ternary lithium batteries specifically includes the following steps: S1: Preparation of functionalized chitosan beads Chitosan was dissolved in acetic acid solution, stirred until completely dissolved, and allowed to stand to remove bubbles. Then it was added dropwise to a NaOH coagulation bath, and after hardening, it was washed with deionized water until neutral to obtain wet coagulated beads. The wet coagulated beads were placed in glutaraldehyde aqueous solution, stirred, filtered, and treated coagulated beads were obtained. The treated coagulated beads were added to polyethylene glycol aqueous solution and stirred. Then epichlorohydrin and ethylenediamine were added and stirred. Then 2-chloromethylpyridine hydrochloride was added and stirred. Finally, it was washed alternately with deionized water and ethanol until neutral to obtain functionalized chitosan coagulated beads. S2: Prepare leachate by acid leaching of waste ternary lithium battery cathode material powder. Add waste ternary lithium battery cathode material powder and deionized water to the reaction flask, add concentrated sulfuric acid under magnetic stirring, stir to obtain acid leaching solution, then add hydrogen peroxide dropwise, heat and stir to react, then cool to room temperature to obtain leachate; S3: Treatment of leachate with functionalized chitosan beads Functionalized chitosan beads were placed in a stirred tank, leaching solution was added, and the mixture was stirred for adsorption. Functionalized chitosan beads were then packed into a chromatography column, and the leaching solution was allowed to flow through the column from top to bottom. After adsorption was completed, solid-liquid separation was performed to obtain beads loaded with transition metals. Subsequently, the beads loaded with transition metals were eluted, and the beads were transferred to a beaker. Dilute sulfuric acid was added, and the mixture was shaken and eluted. The eluents were combined to obtain the transition metal solution. S4: Preparation of ternary precursor powder Then, the transition metal solution, sodium hydroxide solution and ammonia water were added to the reaction vessel and reacted under a nitrogen atmosphere. After the reaction was completed, the product was aged, filtered, and the filter cake was repeatedly washed with deionized water until the pH of the washing liquid was neutral. Finally, the product was dried by blowing air, and after grinding, sieving and electromagnetic iron removal, the ternary precursor powder was obtained.

[0006] Further, step S1, preparing functionalized chitosan beads, includes the following steps: Dissolve 10-15 parts by weight of chitosan in 100-110 parts by weight of acetic acid solution, stir for 2-3 hours until completely dissolved and let stand to remove bubbles, then drop it dropwise into a 1M NaOH coagulation bath containing 30% anhydrous ethanol at a rate of 1 mL / s, harden for 4-6 hours and wash with deionized water until neutral to obtain wet coagulated beads. The wet granules were completely immersed in a 2-3 wt% glutaraldehyde aqueous solution and stirred at room temperature (22-24℃) for 2-4 hours. After filtration, the treated granules were obtained. The treated granules were added to 40-50 parts by weight of polyethylene glycol aqueous solution and stirred at 60-80℃ for 2-4 hours. Then, 4-5 parts by weight of epichlorohydrin and 4-5 parts by weight of ethylenediamine were added and stirred at 50-80℃ for 4-6 hours. Then, 2.5-4.5 parts by weight of 2-chloromethylpyridine hydrochloride were added and stirred at 50-80℃ under nitrogen protection for 8-12 hours. Finally, the mixture was washed alternately with deionized water and 50% ethanol until neutral to obtain functionalized chitosan granules.

[0007] Further, step S2 involves acid leaching of the waste ternary lithium battery cathode material powder to prepare a leachate, including the following steps: Add waste ternary lithium battery cathode material powder and deionized water to the reaction flask. Add concentrated sulfuric acid under magnetic stirring at 100-120 rpm and stir for 10-15 min to obtain an acid leaching solution. Then add hydrogen peroxide dropwise at a rate of 5-10 mL / min. Heat the water bath to 95-100℃ and stir magnetically at 250-300 rpm for 60-70 min. Then cool to room temperature of 22-24℃ to obtain a leachate.

[0008] Further, step S3 involves treating the leachate with functionalized chitosan beads, including the following steps: Functionalized chitosan beads were placed in a stirred tank, and leachate was added. The temperature was controlled at 25-40℃, the stirring speed at 100-150 rpm, and the adsorption time at 4-6 hours, during which the pH was maintained at 3.7-4.5. Functionalized chitosan beads were then packed into a chromatography column with an inner diameter of 2-3 cm, and the leachate was allowed to flow through the chromatography column from top to bottom. The temperature was 25-40℃, and the adsorption time was 1-2 hours. After the adsorption was completed, solid-liquid separation was performed to obtain beads loaded with transition metals. The transition metal-loaded beads were then eluted. The beads were transferred to a beaker, and 0.5-1.0 mol / L dilute sulfuric acid was added, with a volume 2-3 times that of the transition metal-loaded beads. The mixture was eluted by shaking at room temperature for 30-60 minutes, and repeated 2-3 times. The eluents were then combined to obtain the transition metal solution.

[0009] Further, step S4, preparing the ternary precursor powder, includes the following steps: Then, a transition metal solution, a sodium hydroxide solution with a concentration of 4-8 mol / L, and ammonia water with a concentration of 5-10 mol / L are added to a reactor equipped with a stirring and constant temperature system. The reaction temperature is controlled at 60-70℃, the pH is maintained at 10.5-12.0, and the reaction is carried out under a nitrogen atmosphere for 20-24 hours. After the reaction is completed, the product is aged for 1-2 hours. The solid product is filtered and the filter cake is repeatedly washed with deionized water until the pH of the washing liquid is neutral. Finally, the product is dried in an oven at 100-110℃ for 20-22 hours. After grinding, sieving, and electromagnetic iron removal, the ternary precursor powder is obtained.

[0010] Furthermore, the degree of deacetylation of the chitosan in step S1 is ≥90%.

[0011] Furthermore, the concentration of the acetic acid solution in step S1 is 1 wt%.

[0012] Furthermore, in step S2, the mass ratio of the positive electrode material powder, deionized water, concentrated sulfuric acid, and hydrogen peroxide is 1:10:5:(10-13).

[0013] Furthermore, in step S3, the packing height of the functionalized chitosan beads in the chromatography column is 15-20 cm, and the flow rate of the chromatography is 2-5 BV / h.

[0014] The present invention has the following advantages: 1. This invention combines chitosan with 2-chloromethylpyridine hydrochloride. By grafting chitosan with 2-chloromethylpyridine hydrochloride, an aminomethylpyridine group is introduced onto the chitosan. The pyridine nitrogen atom and amino nitrogen atom in this group can work together to form a stable coordination structure with nickel ions, resulting in highly selective adsorption of nickel ions. This allows for preferential capture of nickel in mixed solutions containing cobalt, manganese, and lithium, simplifying the subsequent separation process. At the same time, the hydroxyl and amino groups of chitosan itself also provide a certain auxiliary coordination effect, ensuring that the functional groups are uniformly and stably connected on the cross-linked chitosan three-dimensional network, avoiding functional group detachment. As a result, the functionalized beads exhibit high adsorption capacity during the adsorption process, laying the foundation for obtaining transition metal solutions from the leachate.

[0015] 2. In step S3 of this invention, functionalized chitosan beads are used to treat the leachate. The surface of these functionalized chitosan beads is covalently grafted with aminomethylpyridine functional groups. Under weakly acidic conditions, the nitrogen atoms on these functional groups can form stable five-membered ring chelates with metal ions in the solution. At the same time, the three-dimensional porous structure formed by the pore-forming treatment inside the beads provides a large number of accessible active sites. Combined with the stable framework constructed by double cross-linking, it maintains good mechanical strength and anti-swelling properties in acidic media. The beads after adsorption saturation can also be quickly eluted and regenerated. The eluent is a transition metal solution, which can be directly used as a transition metal source in the co-precipitation process, reducing material costs. Attached Figure Description

[0016] Figure 1 This is a process flow diagram of the recycling process of transition metals in waste ternary lithium batteries according to the present invention. Detailed Implementation

[0017] To enable those skilled in the art to better understand the technical solutions of this invention, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of this invention. Example

[0018] A process for recycling transition metals from spent ternary lithium batteries, such as... Figure 1 As shown, it includes the following steps: S1: Preparation of functionalized chitosan beads Dissolve 12 parts by weight of chitosan in 105 parts by weight of 1 wt% acetic acid solution. The degree of deacetylation of chitosan is ≥90%. Stir for 2.5 hours until completely dissolved and let stand to remove bubbles. Then, drop it dropwise into a 1M NaOH coagulation bath containing 30% anhydrous ethanol at a rate of 1 mL / s. After hardening for 5 hours, wash with deionized water until neutral to obtain wet coagulated beads. The wet granules were completely immersed in a 2.5 wt% glutaraldehyde aqueous solution and stirred at 23°C for 3 hours. After filtration, the treated granules were obtained. The treated granules were added to 45 parts by weight of polyethylene glycol aqueous solution and stirred at 70°C for 3 hours. Then, 4.5 parts by weight of epichlorohydrin and 4.5 parts by weight of ethylenediamine were added and stirred at 70°C for 5 hours. Then, 3.5 parts by weight of 2-chloromethylpyridine hydrochloride were added and stirred at 70°C under nitrogen protection for 10 hours. Finally, the mixture was washed alternately with deionized water and 50% ethanol until neutral to obtain functionalized chitosan granules.

[0019] S2: Prepare leachate by acid leaching of waste ternary lithium battery cathode material powder. Waste ternary lithium battery cathode material powder and deionized water were added to a reaction flask. Concentrated sulfuric acid was added under magnetic stirring at 110 rpm and stirred for 12 min to obtain an acid leaching solution. Then, hydrogen peroxide was added dropwise at a rate of 8 mL / min. The water bath temperature was raised to 98°C, and the mixture was magnetically stirred at 280 rpm for 65 min. The mixture was then cooled to room temperature of 23°C to obtain a leachate. The mass ratio of cathode material powder, deionized water, concentrated sulfuric acid and hydrogen peroxide was 1:10:5:12.

[0020] S3: Treatment of leachate with functionalized chitosan beads Functionalized chitosan beads were placed in a stirred tank, and leaching solution was added. The temperature was controlled at 30℃, the stirring speed at 120 rpm, and the adsorption time was 5 hours, during which the pH was maintained at 4.0. The functionalized chitosan beads were then packed into a chromatography column with an inner diameter of 2 cm, and the leaching solution was allowed to flow through the chromatography column from top to bottom. The temperature was 30℃, and the adsorption time was 1.5 hours. After the adsorption was completed, solid-liquid separation was performed to obtain beads loaded with transition metals. The packing height of the functionalized chitosan beads in the chromatography column was 18 cm, and the flow rate of the chromatography was 3 BV / h.

[0021] Subsequently, the transition metal-loaded beads were eluted. The transition metal-loaded beads were transferred to a beaker, and 0.8 mol / L dilute sulfuric acid was added, with a volume twice that of the transition metal-loaded beads. The mixture was eluted by shaking at room temperature for 45 min, and the process was repeated twice. The eluents were combined to obtain the transition metal solution.

[0022] S4: Preparation of ternary precursor powder Then, a transition metal solution, a 6 mol / L sodium hydroxide solution, and an 8 mol / L ammonia solution were added to a reactor equipped with a stirring and constant temperature system. The reaction temperature was controlled at 65°C, the pH was maintained at 11.0, and the reaction was carried out for 22 hours under a nitrogen atmosphere. After the reaction was completed, the product was aged for 1.5 hours. The solid product was filtered and the filter cake was repeatedly washed with deionized water until the pH of the washing liquid was neutral. Finally, the product was dried in a 105°C oven for 21 hours. After grinding, sieving, and electromagnetic iron removal, the ternary precursor powder was obtained. Example

[0023] A process for recycling transition metals from spent ternary lithium batteries, such as... Figure 1 As shown, it includes the following steps: S1: Preparation of functionalized chitosan beads Dissolve 10 parts by weight of chitosan in 100 parts by weight of 1 wt% acetic acid solution. The degree of deacetylation of chitosan is ≥90%. Stir for 2 hours until completely dissolved and let stand to remove bubbles. Then, drop it dropwise into a 1M NaOH coagulation bath containing 30% anhydrous ethanol at a rate of 1 mL / s. After hardening for 4 hours, wash with deionized water until neutral to obtain wet coagulated beads. The wet granules were completely immersed in a 2 wt% glutaraldehyde aqueous solution and stirred at 22°C for 2 hours. After filtration, the treated granules were obtained. The treated granules were added to 40 parts by mass of polyethylene glycol aqueous solution and stirred at 60°C for 2 hours. Then, 4 parts by mass of epichlorohydrin and 4 parts by mass of ethylenediamine were added and stirred at 50°C for 4 hours. Then, 2.5 parts by mass of 2-chloromethylpyridine hydrochloride were added and stirred at 50°C under nitrogen protection for 8 hours. Finally, the mixture was washed alternately with deionized water and 50% ethanol until neutral to obtain functionalized chitosan granules.

[0024] S2: Prepare leachate by acid leaching of waste ternary lithium battery cathode material powder. Waste ternary lithium battery cathode material powder and deionized water were added to a reaction flask. Concentrated sulfuric acid was added under magnetic stirring at 100 rpm and stirred for 10 min to obtain an acid leaching solution. Then, hydrogen peroxide was added dropwise at a rate of 5 mL / min. The water bath temperature was raised to 95°C, and the mixture was magnetically stirred at 250 rpm for 60 min. The mixture was then cooled to room temperature of 22°C to obtain a leachate. The mass ratio of cathode material powder, deionized water, concentrated sulfuric acid and hydrogen peroxide was 1:10:5:10.

[0025] S3: Treatment of leachate with functionalized chitosan beads Functionalized chitosan beads were placed in a stirred tank, and leaching solution was added. The temperature was controlled at 25℃, the stirring speed at 100 rpm, and the adsorption time was 4 hours, during which the pH was maintained at 3.7. Functionalized chitosan beads were then packed into a chromatography column with an inner diameter of 2 cm, and the leaching solution was allowed to flow through the chromatography column from top to bottom. The temperature was 25℃, and the adsorption time was 1 hour. After the adsorption was completed, solid-liquid separation was performed to obtain beads loaded with transition metals. The packing height of functionalized chitosan beads in the chromatography column was 15 cm, and the flow rate of the chromatography was 2 BV / h.

[0026] Subsequently, the transition metal-loaded beads were eluted. The transition metal-loaded beads were transferred to a beaker, and 0.5 mol / L dilute sulfuric acid was added, with a volume twice that of the transition metal-loaded beads. The mixture was eluted by shaking at room temperature for 30 min, and the process was repeated twice. The eluents were combined to obtain the transition metal solution.

[0027] S4: Preparation of ternary precursor powder Then, a transition metal solution, a 4 mol / L sodium hydroxide solution, and a 5 mol / L ammonia solution were added to a reactor equipped with a stirring and constant temperature system. The reaction temperature was controlled at 60°C, the pH was maintained at 10.5, and the reaction was carried out for 20 hours under a nitrogen atmosphere. After the reaction was completed, the mixture was aged for 1 hour. The solid product was filtered and the filter cake was repeatedly washed with deionized water until the pH of the washing liquid was neutral. Finally, the mixture was dried in a 100°C oven for 20 hours. After grinding, sieving, and electromagnetic iron removal, the ternary precursor powder was obtained. Example

[0028] A process for recycling transition metals from spent ternary lithium batteries, such as... Figure 1 As shown, it includes the following steps: S1: Preparation of functionalized chitosan beads Dissolve 15 parts by mass of chitosan in 110 parts by mass of 1 wt% acetic acid solution. The degree of deacetylation of chitosan is ≥90%. Stir for 3 hours until completely dissolved and let stand to remove bubbles. Then, drop it dropwise into a 1M NaOH coagulation bath containing 30% anhydrous ethanol at a rate of 1 mL / s. After hardening for 6 hours, wash with deionized water until neutral to obtain wet coagulated beads. The wet granules were completely immersed in a 3 wt% glutaraldehyde aqueous solution and stirred at 24°C for 4 hours. After filtration, the treated granules were obtained. The treated granules were added to 50 parts by weight of polyethylene glycol aqueous solution and stirred at 80°C for 4 hours. Then, 5 parts by weight of epichlorohydrin and 5 parts by weight of ethylenediamine were added and stirred at 80°C for 6 hours. Then, 4.5 parts by weight of 2-chloromethylpyridine hydrochloride were added and stirred at 80°C under nitrogen protection for 12 hours. Finally, the mixture was washed alternately with deionized water and 50% ethanol until neutral to obtain functionalized chitosan granules.

[0029] S2: Prepare leachate by acid leaching of waste ternary lithium battery cathode material powder. Waste ternary lithium battery cathode material powder and deionized water were added to a reaction flask. Concentrated sulfuric acid was added under magnetic stirring at 120 rpm and stirred for 15 min to obtain an acid leaching solution. Then, hydrogen peroxide was added dropwise at a rate of 10 mL / min. The water bath temperature was raised to 100°C, and the mixture was magnetically stirred at 300 rpm for 70 min. The mixture was then cooled to room temperature of 24°C to obtain a leachate. The mass ratio of cathode material powder, deionized water, concentrated sulfuric acid, and hydrogen peroxide was 1:10:5:13.

[0030] S3: Treatment of leachate with functionalized chitosan beads Functionalized chitosan beads were placed in a stirred tank, and leaching solution was added. The temperature was controlled at 40℃, the stirring speed at 150 rpm, and the adsorption time was 6 hours, during which the pH was maintained at 4.5. The functionalized chitosan beads were then packed into a chromatography column with an inner diameter of 3 cm, and the leaching solution was allowed to flow through the chromatography column from top to bottom. The temperature was 40℃, and the adsorption time was 2 hours. After the adsorption was completed, solid-liquid separation was performed to obtain beads loaded with transition metals. The packing height of the functionalized chitosan beads in the chromatography column was 20 cm, and the flow rate of the chromatography was 5 BV / h.

[0031] Subsequently, the transition metal-loaded beads were eluted. The transition metal-loaded beads were transferred to a beaker, and 1.0 mol / L dilute sulfuric acid was added, with a volume three times that of the transition metal-loaded beads. The mixture was eluted by shaking at room temperature for 60 min, and the process was repeated three times. The eluents were combined to obtain the transition metal solution.

[0032] S4: Preparation of ternary precursor powder Then, a transition metal solution, an 8 mol / L sodium hydroxide solution, and a 10 mol / L ammonia solution were added to a reactor equipped with a stirring and constant temperature system. The reaction temperature was controlled at 70°C, the pH was maintained at 12.0, and the reaction was carried out for 24 hours under a nitrogen atmosphere. After the reaction was completed, the product was aged for 2 hours. The solid product was filtered and the filter cake was repeatedly washed with deionized water until the pH of the washing liquid was neutral. Finally, it was dried in a 110°C oven for 22 hours. After grinding, sieving, and electromagnetic iron removal, the ternary precursor powder was obtained.

[0033] Comparative Example 1: Compared with Example 1, the difference of Comparative Example 1 is that chitosan is not used in step S1, but polydopamine is used instead of chitosan by mass. The other steps remain the same, and it is referred to as Comparative Example 1.

[0034] Comparative Example 2: Compared with Example 1, Comparative Example 2 differs in that 2-chloromethylpyridine hydrochloric acid is not used in step S2, but an equal mass of N-vinylpyrrolidone is used instead of 2-chloromethylpyridine hydrochloric acid. The remaining steps remain unchanged, and it is referred to as Comparative Example 2.

[0035] The nickel content in waste ternary lithium battery cathode material powder and ternary precursor powder was tested by inductively coupled plasma optical emission spectrometry (ICP-OES) in Examples 1-3 and Comparative Example 1, and the recovery rate was calculated. The results are shown in Table 1.

[0036] Table 1 Example 1 98.6 Example 2 97.9 Example 3 99.2 Comparative Example 1 71.3 Comparative Example 2 83.5 As shown in Table 1, Examples 1-3 all used chitosan beads functionalized with 2-chloromethylpyridine hydrochloride, exhibiting strong selective adsorption of nickel ions, minimal nickel loss after elution, and recovery rates all above 97%. Comparative Example 1 used polydopamine instead of chitosan. While polydopamine has some chelating ability, its sphericity and mechanical strength are poor, resulting in some nickel loss during adsorption and a significant decrease in recovery rate. Comparative Example 2 used N-vinylpyrrolidone instead of 2-chloromethylpyridine hydrochloride. After grafting, N-vinylpyrrolidone showed weaker selectivity for nickel than pyridine groups, leading to incomplete separation of nickel and cobalt during coprecipitation and a lower recovery rate than the examples.

[0037] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims. Parts not described in detail in this specification are prior art known to those skilled in the art.

Claims

1. A process for recycling transition metals from spent ternary lithium batteries, characterized in that, Specifically, the following steps are included: S1: Preparation of functionalized chitosan beads Chitosan was dissolved in acetic acid solution, stirred until completely dissolved, and allowed to stand to remove bubbles. Then it was added dropwise to a NaOH coagulation bath, and after hardening, it was washed with deionized water until neutral to obtain wet coagulated beads. The wet coagulated beads were placed in glutaraldehyde aqueous solution, stirred, filtered, and treated coagulated beads were obtained. The treated coagulated beads were added to polyethylene glycol aqueous solution and stirred. Then epichlorohydrin and ethylenediamine were added and stirred. Then 2-chloromethylpyridine hydrochloride was added and stirred. Finally, it was washed alternately with deionized water and ethanol until neutral to obtain functionalized chitosan coagulated beads. S2: Prepare leachate by acid leaching of waste ternary lithium battery cathode material powder. Add waste ternary lithium battery cathode material powder and deionized water to the reaction flask, add concentrated sulfuric acid under magnetic stirring, stir to obtain acid leaching solution, then add hydrogen peroxide dropwise, heat and stir to react, then cool to room temperature to obtain leachate; S3: Treatment of leachate with functionalized chitosan beads Functionalized chitosan beads were placed in a stirred tank, leaching solution was added, and the mixture was stirred for adsorption. Functionalized chitosan beads were then packed into a chromatography column, and the leaching solution was allowed to flow through the column from top to bottom. After adsorption was completed, solid-liquid separation was performed to obtain beads loaded with transition metals. Subsequently, the beads loaded with transition metals were eluted, and the beads were transferred to a beaker. Dilute sulfuric acid was added, and the mixture was shaken and eluted. The eluents were combined to obtain the transition metal solution. S4: Preparation of ternary precursor powder Then, the transition metal solution, sodium hydroxide solution and ammonia water were added to the reaction vessel and reacted under a nitrogen atmosphere. After the reaction was completed, the product was aged, filtered, and the filter cake was repeatedly washed with deionized water until the pH of the washing liquid was neutral. Finally, the product was dried by blowing air, and after grinding, sieving and electromagnetic iron removal, the ternary precursor powder was obtained.

2. The process for recycling transition metals from spent ternary lithium batteries according to claim 1, characterized in that, Step S1 involves preparing functionalized chitosan beads, including the following steps: Dissolve 10-15 parts by weight of chitosan in 100-110 parts by weight of acetic acid solution, stir for 2-3 hours until completely dissolved and let stand to remove bubbles, then drop it dropwise into a 1M NaOH coagulation bath containing 30% anhydrous ethanol at a rate of 1 mL / s, harden for 4-6 hours and wash with deionized water until neutral to obtain wet coagulated beads. The wet granules were completely immersed in a 2-3 wt% glutaraldehyde aqueous solution and stirred at room temperature (22-24℃) for 2-4 hours. After filtration, the treated granules were obtained. The treated granules were added to 40-50 parts by weight of polyethylene glycol aqueous solution and stirred at 60-80℃ for 2-4 hours. Then, 4-5 parts by weight of epichlorohydrin and 4-5 parts by weight of ethylenediamine were added and stirred at 50-80℃ for 4-6 hours. Then, 2.5-4.5 parts by weight of 2-chloromethylpyridine hydrochloride were added and stirred at 50-80℃ under nitrogen protection for 8-12 hours. Finally, the mixture was washed alternately with deionized water and 50% ethanol until neutral to obtain functionalized chitosan granules.

3. The process for recycling transition metals from spent ternary lithium batteries according to claim 2, characterized in that, Step S2 involves acid leaching of waste ternary lithium battery cathode material powder to prepare a leachate. Includes the following steps: Add waste ternary lithium battery cathode material powder and deionized water to the reaction flask. Add concentrated sulfuric acid under magnetic stirring at 100-120 rpm and stir for 10-15 min to obtain an acid leaching solution. Then add hydrogen peroxide dropwise at a rate of 5-10 mL / min. Heat the water bath to 95-100℃ and stir magnetically at 250-300 rpm for 60-70 min. Then cool to room temperature of 22-24℃ to obtain a leachate.

4. The process for recycling transition metals from spent ternary lithium batteries according to claim 3, characterized in that, Step S3 involves treating the leachate with functionalized chitosan beads, including the following steps: Functionalized chitosan beads were placed in a stirred tank, and leachate was added. The temperature was controlled at 25-40℃, the stirring speed at 100-150 rpm, and the adsorption time at 4-6 hours, during which the pH was maintained at 3.7-4.

5. Functionalized chitosan beads were then packed into a chromatography column with an inner diameter of 2-3 cm, and the leachate was allowed to flow through the chromatography column from top to bottom. The temperature was 25-40℃, and the adsorption time was 1-2 hours. After the adsorption was completed, solid-liquid separation was performed to obtain beads loaded with transition metals. The transition metal-loaded beads were then eluted. The beads were transferred to a beaker, and 0.5-1.0 mol / L dilute sulfuric acid was added, with a volume 2-3 times that of the transition metal-loaded beads. The mixture was eluted by shaking at room temperature for 30-60 minutes, and repeated 2-3 times. The eluents were then combined to obtain the transition metal solution.

5. The process for recycling transition metals in spent ternary lithium batteries according to claim 4, characterized in that, Step S4 prepares the ternary precursor powder, including the following steps: Then, a transition metal solution, a sodium hydroxide solution with a concentration of 4-8 mol / L, and ammonia water with a concentration of 5-10 mol / L are added to a reactor equipped with a stirring and constant temperature system. The reaction temperature is controlled at 60-70℃, the pH is maintained at 10.5-12.0, and the reaction is carried out under a nitrogen atmosphere for 20-24 hours. After the reaction is completed, the product is aged for 1-2 hours. The solid product is filtered and the filter cake is repeatedly washed with deionized water until the pH of the washing liquid is neutral. Finally, the product is dried in an oven at 100-110℃ for 20-22 hours. After grinding, sieving, and electromagnetic iron removal, the ternary precursor powder is obtained.

6. The process for recycling transition metals in spent ternary lithium batteries according to claim 2, characterized in that, The degree of deacetylation of chitosan in step S1 is ≥90%.

7. The process for recycling transition metals in spent ternary lithium batteries according to claim 2, characterized in that, The concentration of the acetic acid solution in step S1 is 1 wt%.

8. The process for recycling transition metals in spent ternary lithium batteries according to claim 3, characterized in that, The mass ratio of the positive electrode material powder, deionized water, concentrated sulfuric acid and hydrogen peroxide in step S2 is 1:10:5:(10-13).

9. The process for recycling transition metals from spent ternary lithium batteries according to claim 4, characterized in that, In step S3, the packing height of the functionalized chitosan beads in the chromatography column is 15-20 cm, and the flow rate of the chromatography is 2-5 BV / h.

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