Method for efficient separation and recovery of valuable metals in waste ternary positive electrode material

Abstract

This invention discloses a method for the efficient separation and recovery of valuable metals from waste ternary cathode materials. The method involves reducing and leaching the waste ternary cathode material using an inorganic dilute acid and an organic reducing agent to obtain a metal mixture. Selective precipitation and impurity removal are then performed by strictly controlling the pH and temperature of the metal mixture to obtain iron-aluminum slag and a nickel-cobalt-manganese-lithium enriched solution. The nickel-cobalt-manganese-lithium enriched solution is then subjected to cation exchange resin adsorption to absorb nickel, cobalt, and manganese ions, followed by leaching to obtain a nickel-cobalt-manganese enriched solution. The remaining liquid is the lithium enriched solution. This method achieves efficient separation and recovery of valuable metals from waste ternary cathode materials, reduces the cost of reducing agents, has a simple process flow, and offers significant economic and environmental benefits.

Description

Technical Field

[0001] This invention relates to a method for recycling waste ternary cathode materials, and more particularly to a method for the comprehensive recycling of valuable metals in waste ternary cathode materials, belonging to the field of waste battery resource recycling technology. Background Technology

[0002] Ternary lithium-ion batteries are widely used in portable electronic products, new energy vehicles, and other fields due to their advantages such as high energy density, low self-discharge rate, and high operating voltage. However, as a consumable product, the annual consumption of lithium-ion batteries is increasing year by year, and the amount of waste is also increasing annually. Waste ternary lithium-ion batteries mainly consist of a positive electrode, a negative electrode, an organic electrolyte, and a separator. Among them, the positive electrode contains a large number of valuable metals, such as nickel, cobalt, manganese, and lithium. Therefore, the resource recycling of valuable metals in waste ternary lithium-ion batteries has become a current research hotspot.

[0003] Currently, hydrometallurgy is the most commonly used method for recycling waste ternary cathode materials. It primarily utilizes acid to dissolve valuable metals in the solid phase, transferring them to the liquid phase. Since nickel, cobalt, and manganese in waste ternary cathode materials exist as high-valence metal oxides, a reducing agent is needed during acid leaching to improve leaching efficiency. In existing technologies, a leaching system composed of hydrogen peroxide and sulfuric acid has been industrially applied. However, while hydrogen peroxide as a reducing agent can reduce the introduction of impurity ions, it also has disadvantages such as unstable storage, relatively high price, and a tendency for overflow during the leaching process. Therefore, organic acid leaching systems, which offer milder leaching conditions, lower prices, and higher leaching efficiency, have become a research hotspot. Organic acid leaching systems mainly include organic acid + inorganic reducing agent, organic acid + organic reducing agent, and inorganic acid + organic reducing agent. Regardless of the chosen leaching system, the resulting ternary acid leaching solution will contain a large amount of organic matter. However, current methods for the efficient separation and recovery of nickel, cobalt, and manganese primarily employ solvent extraction. Cyanex 272 extractant is widely used by companies due to its significant extraction and separation effects on nickel and cobalt. However, the presence of residual organic matter in the acid leaching solution inevitably leads to a series of problems during extraction, such as low extraction efficiency and extractant emulsification. Therefore, the separation and recovery of valuable metals like nickel, cobalt, manganese, and lithium in acidic organic solutions remains a challenging problem for the industry.

[0004] Chinese patent (CN 108913873 A) discloses a method for recovering high-value-added metals from spent nickel-cobalt-manganese lithium-ion batteries. The method first involves thoroughly discharging the spent ternary lithium-ion batteries to obtain cathode powder, which is then heat-treated to remove impurities such as conductive agents and binders. Next, the heat-treated cathode powder and active additives undergo mechanical-chemical synergistic activation. The activated cathode powder is then subjected to reducing acid leaching with citric acid-glucose, resulting in the stepwise precipitation of valuable metals (nickel, cobalt, manganese, and lithium) from the leaching solution. While this method utilizes an acid leaching system composed of organic acid and organic reducing agent to achieve efficient leaching of valuable metals, the subsequent separation and recovery of these metals rely on chemical precipitation, resulting in a long and complex process with significant losses, particularly of Li, which has a small ionic radius and is easily adsorbed and co-precipitated, leading to further losses. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a method for the efficient separation and recovery of valuable metals in waste ternary cathode materials. This method employs a process combining organic matter reduction acid leaching, high-temperature precipitation for impurity removal, and ion exchange separation to achieve efficient separation and recovery of valuable metals in waste ternary materials. It also reduces the cost of reducing agents, has a simple process flow, and offers significant economic and environmental benefits.

[0006] To achieve the above-mentioned technical objectives, this invention provides a method for the efficient separation and recovery of valuable metals from waste ternary cathode materials, the method comprising the following steps:

[0007] 1) The waste ternary cathode material is reduced and leached using inorganic dilute acid and organic reducing agent to obtain a metal mixture;

[0008] 2) Adjust the pH of the metal mixture to 3-5, and carry out precipitation and impurity removal at 30-95℃ for 30-150 min to obtain iron-aluminum slag and nickel-cobalt-manganese-lithium enriched solution.

[0009] 3) After adsorbing nickel ions, cobalt ions and manganese ions into the nickel-cobalt-manganese-lithium enrichment solution with cation exchange resin, the nickel-cobalt-manganese enrichment solution is obtained by analysis, and the remaining liquid after adsorption is the lithium enrichment solution.

[0010] The method for efficient separation and recovery of valuable metals in waste ternary cathode materials provided by this invention specifically includes three main steps: reduction acid leaching, high-temperature impurity removal, and resin separation. It can not only achieve efficient separation and recovery of valuable metals, but also reduce costs and simplify the process. More specifically, reducing acid leaching using inorganic dilute acid and organic reducing agents can achieve efficient leaching of valuable metals from waste ternary materials. The addition of organic reducing agents significantly improves the leaching efficiency, with leaching rates of high-value lithium, nickel, cobalt, and manganese ions reaching over 98%. However, the leaching rates of impurity metal ions such as aluminum, iron, and copper are also high. For the separation of these impurity metal ions, this invention employs a high-temperature precipitation method. By strictly controlling temperature, pH conditions, and time, selective precipitation of impurity metal ions such as iron, copper, and aluminum ions can be achieved. This efficiently removes impurity metal ions while reducing the loss of valuable metal ions such as nickel, cobalt, manganese, and lithium ions. In particular, the pH at which the impurity metal ions are precipitated is also the optimal pH for subsequent adsorption of nickel, cobalt, and manganese ions by the cation exchange resin, providing a favorable pH environment for subsequent processes. A large amount of organic matter remains in the solution system after removing impurity metal ions. This organic matter contains oxygen-containing groups that have a certain complexing effect on transition metal ions, making it impossible to separate transition metal ions from lithium ions using conventional extraction methods. To avoid the influence of residual organic matter during the leaching process on the extraction and separation of metal ions, this invention uses cation exchange resin adsorption to separate lithium ions from nickel, cobalt, and manganese ions. Lithium ions can be recovered separately for the preparation of lithium carbonate, while nickel, cobalt, and manganese ions can be directly used to prepare ternary cathode materials, thus truly achieving efficient separation and recovery of valuable metals in waste ternary cathode materials.

[0011] As a preferred embodiment, the concentration of the inorganic dilute acid is 1.0–4.0 mol / L. If the concentration of the inorganic dilute acid is too low, a larger volume of inorganic dilute acid is required to complete the leaching process; if the concentration of the inorganic dilute acid is too high, more alkali solution is required to neutralize the acidity and complete the neutralization and precipitation process, which increases the cost of acid and alkali consumption.

[0012] As a preferred embodiment, the inorganic dilute acid includes at least one of dilute phosphoric acid, dilute sulfuric acid, and dilute nitric acid.

[0013] As a preferred embodiment, the organic reducing agent is a carbohydrate compound, specifically including at least one of monosaccharides, disaccharides, and polysaccharides. For example, at least one of glucose, sucrose, and cellulose. As a more preferred embodiment, the amount of the organic reducing agent is 4-24% of the mass of the waste ternary cathode material. More specifically, the organic reducing agent can be biological organic waste rich in glucose, sucrose, cellulose, etc., or it can be commercial reagents such as analytical-grade glucose, sucrose, and cellulose. The most preferred organic reducing agent is a monosaccharide. The advantages of using an organic reducing agent compared to traditional reducing agents such as hydrogen peroxide are: milder leaching conditions (hydrogen peroxide as a reducing agent results in a violent reaction and is prone to overflow), lower price, and more stable storage.

[0014] As a preferred embodiment, the reduction leaching conditions are: a liquid-to-solid ratio of 6–14 mL / g, a leaching temperature of 333 K–363 K, and a leaching time of 30–240 min. Through thermodynamic analysis of the feasibility of the reduction acid leaching stage and extensive experimental exploration of the influence of different factors on leaching, efficient leaching of valuable metals from waste ternary cathode materials can be achieved under optimized reduction leaching conditions.

[0015] As a preferred embodiment, the cation exchange resin comprises a strongly acidic cation exchange resin and / or a weakly acidic cation exchange resin. Specifically, the cation exchange resins selected are D001, D732, and D113. Among them, the weakly acidic cation exchange resin D113 has a larger adsorption capacity and exhibits selectivity for the adsorption of nickel, cobalt, and manganese ions. During the adsorption process, it is unaffected by organic matter and lithium ions, thus making it more advantageous for the selective adsorption of nickel, cobalt, and manganese ions from complex mixed metal ion solutions containing organic matter.

[0016] As a preferred embodiment, the adsorption conditions are: pH 3–5, room temperature, and time 30–180 min. A further preferred pH is 4.75–5. pH has a significant impact on the adsorption effect. Too high a pH can easily cause hydrolysis and precipitation of nickel, cobalt, and manganese ions. If the pH is too low, the adsorption capacity and selectivity for nickel, cobalt, and manganese ions are reduced due to the influence of acid protons. Therefore, within the preferred pH range, the selective and efficient adsorption of nickel, cobalt, and manganese ions by the cation exchange resin is more favorable.

[0017] The present invention uses cation exchange resin adsorption to achieve efficient separation of lithium ions from nickel, cobalt and manganese ions. Furthermore, the residual organic matter in the solution system does not affect the exchange process of metal ions by the cation exchange resin, thus overcoming the technical defect that existing organic acid leaching systems are difficult to use extraction methods to efficiently separate transition metal ions.

[0018] As a preferred embodiment, the desorption is performed using dilute sulfuric acid or dilute hydrochloric acid as the eluent, and the concentration of the eluent is 1–3 mol / L.

[0019] As a preferred embodiment, the pH adjustment is performed using a sodium hydroxide solution.

[0020] As a preferred embodiment, the precipitation and impurity removal conditions are: pH of the metal mixture adjusted to 4.75–5, temperature 75–90℃, and time 120–150 min. Numerous experiments have shown that with increasing pH, the precipitation efficiency of almost all metal ions increases to varying degrees. However, the precipitation efficiency of copper, aluminum, and iron ions is significantly affected by pH, especially aluminum and copper ions. At pH 4.75–5, the precipitation efficiency increases significantly, differing considerably from that of nickel, cobalt, and manganese ions. Therefore, the optimal pH range is controlled within 4.75–5. During the precipitation and impurity removal process, under certain pH conditions, higher temperatures and longer times result in lower precipitation efficiency for nickel, cobalt, and manganese ions, while the precipitation efficiency of impurity metal ions such as copper, aluminum, and iron remains essentially unchanged. This achieves precipitation of impurity metal ions such as copper, aluminum, and iron ions while maintaining the lowest possible precipitation efficiency for nickel, cobalt, and manganese ions, thus reducing the loss of useful metal ions.

[0021] This invention provides a method for the efficient separation and recovery of valuable metals from waste ternary cathode materials, comprising the following steps:

[0022] Organic matter reduction acid leaching process (S1): A certain amount of waste ternary cathode powder is added to a dilute sulfuric acid solution of a certain concentration, and a certain amount of organic reducing agent is added to the solution. The mixture is placed in a constant temperature water bath and reacted for a period of time. After the acid leaching reaction reaches equilibrium, solid-liquid separation is carried out to obtain a metal mixture and carbon slag.

[0023] High-temperature precipitation and impurity removal process (S2): The pH value of the metal mixture obtained in step S1 is slowly adjusted by dilute sodium hydroxide solution or dilute ammonia water. The adjusted mixture is placed in a constant temperature water bath and heated to the set temperature. The reaction is carried out under constant temperature conditions for a certain period of time. After the precipitation reaction reaches equilibrium, solid-liquid separation is performed to obtain nickel-cobalt-manganese-lithium filtrate and iron-aluminum-rich slag.

[0024] Ion exchange process (S3): A certain amount of dry resin is added to the nickel-cobalt-manganese-lithium mixture and placed in a constant temperature shaking box for a period of time. The resin after adsorption is desorbed using dilute sulfuric acid solution. The resulting nickel-cobalt-manganese-rich solution is precipitated to synthesize a ternary precursor. The adsorbed solution is enriched to precipitate and synthesize lithium carbonate.

[0025] Compared with existing technologies, the beneficial technical effects of this invention are as follows:

[0026] (1) This invention proposes a new method for the efficient separation and recovery of valuable metals in waste ternary cathode materials. The efficient leaching of valuable metals in waste ternary cathode materials can be achieved by using an organic reducing agent + inorganic dilute acid. On this basis, the selective precipitation of impurity metal ions such as aluminum ions, iron ions and copper ions is achieved by high temperature precipitation method. Then, the lithium ions in the organic solution system are efficiently separated from nickel ions, cobalt ions and manganese ions by adsorption using cation exchange resin. Finally, high-purity nickel cobalt manganese enriched solution and lithium enriched solution are obtained, which can be directly used to prepare ternary cathode materials and lithium carbonate.

[0027] (2) Traditional leaching systems for waste ternary cathode materials use sulfuric acid and hydrogen peroxide. While hydrogen peroxide, as a reducing agent, can achieve efficient leaching of valuable metals in waste ternary cathode materials without introducing impurity ions, it is expensive and the reaction process is violent, easily causing problems such as overflow. Leaching systems composed of organic reducing agents and organic acids can also achieve efficient leaching of valuable metals, but the organic leachate entering the traditional extraction and separation system will inevitably affect the extraction effect, and the precipitation of impurity metal ions in the leaching system is difficult. This invention, on the one hand, uses a high-temperature precipitation method to achieve selective precipitation of impurity metal ions, efficiently removing impurity metal ions while reducing the loss of valuable metal ions such as nickel, cobalt, manganese, and lithium ions. On the other hand, it uses cation exchange resin adsorption to separate lithium ions from nickel, cobalt, and manganese ions, avoiding the influence of residual organic matter on the extraction and separation of metal ions during the leaching process.

[0028] (3) The method for efficient separation and recovery of valuable metals in waste ternary cathode materials provided by the present invention reduces the cost of reducing agent, has a simple process flow, and has a high recovery rate of valuable metals, resulting in significant economic and environmental benefits. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0030] Figure 1 The image shows the XRD pattern of the waste ternary cathode material in Example 1.

[0031] Figure 2 The effects of different initial pH, reaction time, and reaction temperature on the precipitation and impurity removal process; from Figure 2The results showed that the optimal precipitation conditions were: initial pH 5, reaction time 120 min, and reaction temperature 75℃. Under these conditions, the precipitation rates of valuable metals nickel, cobalt, manganese, and lithium were all below 3%, while the precipitation rates of impurity metals were all above 90%.

[0032] Figure 3 SEM images of waste ternary cathode material before and after leaching (a: waste ternary cathode material, b: leaching residue); by comparing the waste material before and after leaching, the waste ternary material was a regular round particle before leaching. After reduction acid leaching, the spherical particle was destroyed and the structure became porous and irregular.

[0033] Figure 4 The images show the SEM images of the cation exchange resin before and after adsorption in Example 1. Before adsorption, the surface structure of the cation exchange resin is loose and porous. After adsorption of valuable metals, many fine particles are distributed in the gaps between the porous structures on its surface. Further mapping shows that the fine particles are valuable metals such as nickel, cobalt, and manganese.

[0034] Figure 5 To investigate the effect of different initial pH values ​​in the purified solution on the resin adsorption efficiency; by increasing the pH of the nickel-cobalt-manganese-lithium-rich filtrate, the adsorption capacity Q of the resin for valuable metals was observed. e The separation coefficient β(Me / Li) between valuable metals Me (Ni, Co, Mn) and Li gradually increases, indicating that valuable metals Me (Ni, Co, Mn) and Li have a good separation effect when the pH value is close to 5.

[0035] Figure 6 The image shows the XRD pattern of the lithium carbonate product in Example 1. By comparing it with the XRD card of standard lithium carbonate, it can be seen that the prepared lithium carbonate product has high crystallinity and low impurity content. Detailed Implementation

[0036] To illustrate the technical content, objectives, and effects of the present invention in detail, the following embodiments are described in conjunction with the accompanying drawings.

[0037] Example 1

[0038] Step 1: After pretreatment, waste ternary lithium batteries are used to obtain waste ternary lithium powder. The content of each component in the obtained powder is: 2.73% Al, 1.31% Fe, 0.22% Cu, 24.9% Ni, 9.1% Co, 14.3% Mn, and 5.86% Li. Take 5g of waste ternary lithium powder and add 3mol / L sulfuric acid solution at a liquid-to-solid ratio of 12mL / g. Add 1g of glucose, an organic reducing agent, to the solution and leach the powder at room temperature for 3 hours. The leaching rate of metal ions in the resulting filtrate is: Al 87.35%, Fe 99.8%, Cu 99.2%, Li 99.6%, Ni 98.5%, Co 99.4%, and Mn 98.9%.

[0039] Step 2: Adjust the pH of the organic leachate to 5 with 1 mol / L dilute sodium hydroxide solution, react at 30℃ for 30 min. After the reaction, the precipitation rate of metal ions in the filtrate is Al 95%, Fe 89.5%, Cu 88.9%, and the concentrations of other valuable metals (Ni, Co, Mn, Li) remain basically unchanged.

[0040] Step 3: Add 20g of dry D113 resin to 100mL of nickel-cobalt-manganese-lithium filtrate, and react in a constant-temperature shaking incubator for 6 hours. After adsorption reaches equilibrium, the resin is desorbed with 1mol / L dilute sulfuric acid solution to obtain a nickel-cobalt-manganese-rich solution. The nickel-cobalt-manganese-rich solution is then precipitated with ammonia to synthesize a nickel-cobalt-manganese precursor. The lithium-rich solution (4088mg / L Li) is returned to Step 1 for Li enrichment, followed by precipitation to synthesize lithium carbonate. The recoveries of nickel, cobalt, and manganese are 97%, 98%, and 97%, respectively, and the lithium recovery rate can reach 99% after cyclic enrichment.

[0041] Example 2

[0042] Step 1: After pretreatment, waste ternary lithium batteries are used to obtain waste ternary lithium powder. The content of each component in the obtained powder is: 2.73% Al, 1.31% Fe, 0.22% Cu, 24.9% Ni, 9.1% Co, 14.3% Mn, and 5.86% Li. Take 5g of waste ternary lithium powder and add 2mol / L sulfuric acid solution at a liquid-to-solid ratio of 10mL / g. Add 3g of glucose, an organic reducing agent, to the solution and leach the powder at room temperature for 3 hours. The leaching rate of metal ions in the resulting filtrate is: Al 86.65%, Fe 98.2%, Cu 98.5%, Li 98.9%, Ni 99.1%, Co 99.1%, and Mn 99.2%.

[0043] Step 2: Adjust the pH of the organic leachate to 5 with 1 mol / L dilute sodium hydroxide solution, react at 30℃ for 30 min. After the reaction, the filtrate contains 94.6% Al, 86.1% Fe, 87.3% Cu, and the concentrations of other valuable metals (Ni, Co, Mn, Li) remain basically unchanged.

[0044] Step 3: Add 20g of dry D113 resin to 100mL of nickel-cobalt-manganese-lithium filtrate, and react in a constant temperature shaking oven for 6h. After adsorption reaches equilibrium, the adsorption resin is desorbed with 1mol / L dilute sulfuric acid solution to obtain a nickel-cobalt-manganese-rich solution. The nickel-cobalt-manganese-rich solution precipitate is used to synthesize a nickel-cobalt-manganese precursor with ammonia water. The lithium-rich solution (3879mg / L Li) is returned to Step 1 for Li enrichment, and then precipitated to synthesize lithium carbonate product.

[0045] Example 3

[0046] Step 1 is the same as in Example 1:

[0047] In step 2, the pH values ​​of the organic leachate were adjusted to 3.75, 4, 4.5, 4.75, and 5, respectively, and the reaction was carried out at 30°C for 30 minutes. The precipitation rate of metal ions in the filtrate after the reaction was as follows: Figure 2 As shown in Figure a, with increasing pH, the precipitation rates of impurity metal ions Al, Fe, and Cu increase, achieving a good removal effect. However, the precipitation rate of valuable metals is relatively high, requiring further optimization of precipitation conditions.

[0048] Example 4

[0049] Step 1 is the same as in Example 1:

[0050] In step 2, the pH of the organic leachate was adjusted to 5, and the reaction was carried out at room temperature for 30, 60, 90, 120, and 150 minutes respectively. The precipitation rate of metal ions in the filtrate after the reaction was as follows: Figure 2 As shown in Figure b, the precipitation rates of impurity metal ions Al, Fe, and Cu do not change significantly with increasing reaction time, but the precipitation rate of valuable metals gradually decreases. This is mainly because the concentration of valuable metals in the organic leachate is too high, making it prone to localized over-alkalinity during pH adjustment, leading to precipitation loss. Therefore, extending the reaction time is beneficial for the redissolution of valuable metal hydroxide precipitates, thus reducing losses.

[0051] Example 5

[0052] Step 1 is the same as in Example 1:

[0053] In step 2, the pH of the organic leachate was adjusted to 5, and the reaction was carried out at 30, 45, 60, 75, and 90°C for 120 min respectively. The precipitation rate of metal ions in the filtrate after the reaction is as follows: Figure 2As shown in Figure c, the precipitation of impurity metals Al, Fe, and Cu did not change significantly with increasing reaction temperature, while the precipitation rate of valuable metals decreased slightly. This indicates that increasing the temperature is beneficial for the redissolution of valuable metal hydroxide precipitates, similar to the results at different reaction times.

[0054] Example 6

[0055] Step 1 is the same as in Example 1;

[0056] Step 2 is the same as in Example 1;

[0057] In step 3, the pH of the nickel-cobalt-manganese-lithium filtrate was adjusted to 3.25, 3.5, 3.75, 4.25, 4.75, and 5.2. At room temperature, an equal amount of 20g of dry D113 resin was added to 100mL of the adjusted filtrate to carry out the adsorption reaction. Its adsorption performance for valuable metals is as follows: Figure 5 As shown, the adsorption capacity of the resin for valuable metals Me (Ni, Co, Mn) gradually increases with increasing pH. The separation coefficient β(Me / Li) between Me (Ni, Co, Mn) and Li also gradually increases. Further increasing the pH of the adsorption solution leads to the precipitation of nickel, cobalt, and manganese. Furthermore, adjusting the pH to 5 during the high-temperature precipitation process significantly improves impurity removal; therefore, pH adjustment is unnecessary for the nickel-cobalt-manganese-lithium-rich filtrate before adsorption.

[0058] Example 7

[0059] In Example 1, sucrose was used instead of glucose as the organic reducing agent in step 1, and the remaining processes were performed as in Example 1. During the leaching process, there was a significantly larger amount of filter residue, indicating incomplete leaching. This suggests that a large amount of valuable metals remained in the solid phase. The leaching rates of metal ions in the resulting filtrate were: Al 81.65%, Fe 88.2%, Cu 78.5%, Li 88.9%, Ni 79.1%, Co 79.1%, and Mn 82.2%. This indicates that using monosaccharides as the reducing agent in the leaching process yields significantly better leaching results than using disaccharides.

[0060] Example 8

[0061] In step 2 of Example 2, a 1:1 dilute ammonia solution was used instead of a 1 mol / L dilute sodium hydroxide solution to adjust the pH of the leachate to 5. The remaining procedures were performed as in Example 2. The precipitation rates of each metal ion were Al 6.5%, Fe 0.22%, Cu 1.47%, Li 1.36%, Ni 5.19%, Co 1.9%, and Mn 3.86%. During the precipitation and impurity removal process, it was found that almost no impurities were precipitated, and the precipitation effect was poor. The ammonia solution had a strong binding ability with metal ions, and the actual precipitation pH value may be higher.

[0062] Example 9

[0063] In step 3 of Example 1, a strongly acidic cation exchange resin D001 was used instead of D113 resin to adsorb 100 mL of a nickel-cobalt-manganese-lithium solution. The remaining procedures were performed as in Example 1. During the adsorption process, it was found that the concentration of Li decreased significantly compared to the solution after impurity removal, and the Li adsorption rate was 41.8%. This indicates that D113 is the most effective cation exchange resin for adsorbing nickel, manganese, and cobalt ions from acidic solutions containing organic matter.

[0064] The above description is a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitution or modification made by those skilled in the art within the scope of the technology disclosed in the present invention based on the technical solution and inventive concept of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A method for efficient separation and recovery of valuable metals from waste ternary cathode materials, characterized in that: Includes the following steps: 1) The waste ternary cathode material is reduced and leached using inorganic dilute acid and organic reducing agent to obtain a metal mixture; 2) Adjust the pH of the metal mixture to 4.75~5, and carry out precipitation and impurity removal at 75~90℃ for 120~150 min to obtain iron-aluminum slag and nickel-cobalt-manganese-lithium enriched solution. 3) After adsorbing nickel ions, cobalt ions and manganese ions into the nickel-cobalt-manganese-lithium enrichment solution with cation exchange resin, the nickel-cobalt-manganese enrichment solution is obtained by desorption, and the remaining liquid after adsorption is the lithium enrichment solution; the cation exchange resin is D113; the adsorption conditions are: pH 4.75~5, temperature room temperature, and time 30~180 min.

2. The method for efficient separation and recovery of valuable metals in waste ternary cathode materials according to claim 1, characterized in that: The inorganic dilute acid includes at least one of dilute phosphoric acid, dilute sulfuric acid, and dilute nitric acid; The organic reducing agent includes at least one of monosaccharides, disaccharides, and polysaccharides.

3. The method for efficient separation and recovery of valuable metals in waste ternary cathode materials according to claim 2, characterized in that: The concentration of the inorganic dilute acid is 1.0~4.0 mol / L; The amount of the organic reducing agent used is 4% to 24% of the mass of the waste ternary cathode material.

4. A method for efficient separation and recovery of valuable metals in waste ternary cathode materials according to any one of claims 1 to 3, characterized in that: The conditions for the reduction leaching are: a leaching liquid-to-solid ratio of 6-14 mL / g, a leaching temperature of 333K-363K, and a leaching time of 30-240 min.

5. A method for efficient separation and recovery of valuable metals in waste ternary cathode materials according to claim 1, characterized in that: The desorption is performed using dilute sulfuric acid and / or dilute hydrochloric acid as the desorption solution; the concentration of the desorption solution is 1~3 mol / L.

6. The method for efficient separation and recovery of valuable metals in waste ternary cathode materials according to claim 1, characterized in that: The pH adjustment was performed using a sodium hydroxide solution.

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