Novel process for comprehensive recovery of valuable metals from ternary positive electrode material powder

Abstract

The present invention provides a novel process for comprehensive recovery of valuable metals from ternary positive electrode material powder, which comprises the steps of dissolution of positive electrode material powder, separation of metal salts, extraction and back extraction, treatment of a lithium salt, etc., wherein acid produced by electrolysis can be recycled, and a lithium salt solution can be further used for preparing a lithium carbonate product. The process has significant advantages: comprehensive and efficient resource recovery, high recovery rate of valuable metals, and high precision in terms of metal separation. The process is environmentally friendly and cost-effective, and allows for the recycling of auxiliary materials, thereby reducing costs and environmental pollution. The product has good quality, low impurity content, and stable performance, so as to meet high-end market demands while enhancing market competitiveness and added value. The process has significant advantages in the aspects of resource recovery, environmental protection cost, product quality, etc., and has a wide application prospects and market values.

Description

A new process for the comprehensive recovery of valuable metals from ternary cathode material powder Technical Field

[0001] This invention relates to a novel process for the comprehensive recovery of valuable metals from ternary cathode material powder. Background Technology

[0002] With the rapid development of new energy vehicles, electronic equipment, and other industries, the use of ternary lithium batteries and lithium iron phosphate batteries has increased dramatically. After these lithium batteries reach their service life, some with better performance are reused in stages, while most are directly scrapped and dismantled, with the cathode being ground into powder, commonly known as "black powder" or "urban mining." The large amount of ternary cathode material powder generated after their disposal urgently needs effective treatment and recycling. However, current ternary cathode material powder recycling processes mainly rely on wet processes, which have several problems: In terms of resource recovery, traditional processes are not comprehensive enough in recovering valuable metals such as nickel, cobalt, manganese, and lithium, resulting in low recovery rates and significant resource waste. This fails to fully meet the needs of resource recycling and is detrimental to improving corporate economic efficiency and implementing sustainable development concepts. During production, the lithium content in the lithium salt solution is low, and lithium is mixed with alkali metal salts such as sodium and potassium, making effective separation difficult and resulting in low lithium recovery rates.

[0003] In the metal separation stage, traditional processes often lack precise separation methods, making it difficult to effectively separate lithium salt solutions from nickel, cobalt, and manganese metal salt solutions. This results in high impurity content and low product quality during subsequent metal salt processing, leading to low direct recovery rates of various valuable metals, which in turn affects the added value of the product and limits the company's competitiveness in the market. From an environmental and cost perspective, the acids and alkalis used in traditional processes are essential consumables that cannot be recycled, requiring continuous purchase of new auxiliary materials, resulting in high auxiliary material costs. Furthermore, the large quantities of acids and alkalis used in production generate pollutants such as sodium salts that undergo neutralization reactions, producing large amounts of salt solutions that companies lack effective treatment methods for and can only discharge. This results in significant emissions of wastewater, waste gas, and waste residue, increasing environmental pollution control costs and failing to meet increasingly stringent environmental requirements, posing a serious challenge to the company's sustainable development. Furthermore, traditional processes often employ chemical purification methods during the impurity removal process, which can easily introduce additional impurities. This results in lower purity and quality of nickel salts, cobalt salts, manganese salts, as well as lithium carbonate or lithium hydroxide products, reaching only industrial-grade levels. If companies wish to produce high-quality products, further purification of industrial-grade materials is required, significantly increasing production costs. This fails to meet the demands of the high-end market for high-quality battery materials, thus hindering the development and upgrading of related industries.

[0004] In summary, existing technologies have many shortcomings in the comprehensive utilization of ternary cathode material powder. There is an urgent need for a new process that can comprehensively and efficiently recover resources, is environmentally friendly and low-cost, and produces high-quality products to solve these problems. This invention is based on this background and proposes a new process for the comprehensive recovery of valuable metals in ternary cathode material powder. Summary of the Invention

[0005] The purpose of this invention is to provide a new process for the comprehensive recovery of valuable metals from ternary cathode material powder, so as to solve the problems mentioned in the background art.

[0006] To solve the above-mentioned technical problems, the technical solution provided by this invention is: a new process for comprehensively recovering valuable metals from ternary cathode material powder, specifically including the following steps:

[0007] 1) Dissolving the positive electrode material powder: The ternary battery positive electrode material powder is slurried, then acid is added for acid hydrolysis. After the reaction is complete, solid-liquid separation is performed to obtain activated carbon powder and leachate. The activated carbon powder needs to be washed 2-3 times in countercurrent to ensure the leaching rate.

[0008] 2) Separation of metal salt solutions: The leachate is passed through a liquid separation device to separate lithium salt solutions and nickel, cobalt, and manganese metal salt solutions;

[0009] 3) Extraction and Back-extraction: The separated nickel, cobalt, and manganese metal salts are extracted to obtain nickel and cobalt salts. The sodium salt raffinate is passed through a saponified extractant and then enters an electrolysis device to obtain sodium hydroxide and acid. The solution is then extracted with a saponified P204 extractant organic solution. The nickel, cobalt, and other metal ions will replace the sodium ions in the extractant and enter the organic phase. The replaced sodium ions enter the raffinate. This process is called extraction. The saturated organic phase is back-extracted with a sulfuric acid solution of a certain concentration to obtain nickel sulfate and sulfuric acid solution. After passing through a P507 to separate nickel sulfate and cobalt sulfate, the nickel sulfate and sulfuric acid solution are evaporated and crystallized to obtain nickel sulfate and cobalt sulfate products. Alternatively, nickel sulfate and cobalt sulfate can be processed into nickel oxide and cobalt oxide. The empty organic phase is then acid-washed and re-saponified.

[0010] 4) Treatment of raffinate: In traditional processes, raffinate can only be discharged externally. In this invention, the raffinate is electrolyzed through a bipolar membrane to regenerate sulfuric acid solution and sodium hydroxide solution.

[0011] 5) Lithium salt treatment: The separated lithium salt solution is electrolyzed through a bipolar membrane to produce hydrochloric acid solution and lithium hydroxide solution. The lithium hydroxide solution is then evaporated and crystallized to produce lithium hydroxide monohydrate product.

[0012] As a preferred embodiment, the sulfuric acid solution obtained by electrolysis in step 4) is used for the acid hydrolysis of the positive electrode material powder in the first stage of 1), and the sodium hydroxide solution obtained by electrolysis is used for the saponification of the empty organic phase in step 3).

[0013] As a preferred embodiment, the hydrochloric acid solution obtained by electrolysis in step 5) is used for 1) acid hydrolysis of the positive electrode material powder. The lithium hydroxide solution obtained by electrolysis can be prepared into lithium hydroxide monohydrate solution by evaporation and crystallization, or lithium carbonate can be prepared by passing carbon dioxide through it. The prepared lithium hydroxide monohydrate or lithium carbonate can be used to prepare battery-grade products after slight treatment.

[0014] As a preferred embodiment, the acid used in step 1) for acid hydrolysis is a mixture of sulfuric acid and hydrochloric acid obtained from electrolysis in steps 4) and 5).

[0015] As a preferred embodiment, the salt solution in step 2) contains SO4. 2- Cl - Li + Ni 2+ Co 2+ A plasma solution; this solution can be filtered through a nanofiltration membrane to remove Cl... - Li + With SO4 2- Ni 2+ Co 2+ Effective separation yields LiCl solution and sulfate solutions of other metals.

[0016] As a preferred embodiment, the salt solution to be separated in step 2) is a lithium chloride solution and other sulfate solutions.

[0017] The advantages of this invention are: 1. Comprehensive and efficient resource recycling.

[0018] High recovery rate of valuable metals: This process can effectively separate lithium from other high-valent metals such as nickel and cobalt, greatly improving the direct recovery rate of lithium. For example, nanofiltration membranes can effectively separate monovalent cations and anions from high-valent cations and anions, preventing lithium ions from entering subsequent processes and improving the direct recovery rate of lithium. This process separates lithium from other divalent metals before the leachate enters the extraction process, preventing lithium from mixing with sodium salts in subsequent processes and ultimately becoming difficult to separate effectively from sodium. It maximizes the recycling of resources, bringing considerable economic benefits to enterprises and conforming to the concept of sustainable resource utilization. The bipolar membrane electrolysis used in this invention can effectively increase the concentration of the lithium hydroxide solution obtained by electrolysis, solving the problem of low lithium recovery rate caused by excessively low lithium solution concentration in the production of recycled materials.

[0019] This ensures the purity and efficiency of subsequent metal salt processing. This precise separation lays a solid foundation for subsequent extraction, back-extraction, and lithium salt processing steps, avoiding problems such as high impurity content and low quality caused by incomplete metal separation, thus improving the overall product quality and added value of the process.

[0020] II. The process is environmentally friendly and low-cost.

[0021] Auxiliary material recycling reduces costs: In step 4), the acid obtained from electrolysis is recycled to dissolve the cathode material powder, achieving acid recycling and significantly reducing acid consumption and auxiliary material costs. Simultaneously, throughout the entire process, all acids (such as sulfuric acid and hydrochloric acid) and alkalis (such as sodium hydroxide) can be recycled, eliminating the need for external sodium salt discharge. This not only saves substantial auxiliary material procurement costs but also reduces environmental pollution control costs associated with auxiliary material emissions, demonstrating significant economic and environmental benefits. Calculations show that compared to traditional processes, this technology can reduce auxiliary material costs by over 80%, saving companies a significant amount of money.

[0022] Reduced environmental pollution: Due to the recycling of auxiliary materials such as acids and alkalis in the process and the absence of pollutants such as sodium salts discharged externally, environmental pollution is greatly reduced. Compared with traditional processes, this process significantly reduces the emissions of wastewater, waste gas, and waste residue, meeting current stringent environmental protection requirements, which is conducive to the sustainable development of enterprises and makes a positive contribution to environmental protection.

[0023] III. Excellent product quality

[0024] Low impurity content: This process does not use the chemical impurity removal methods of traditional processes during the impurity removal process, so it will not introduce other impurities. This ensures that the produced nickel salt, cobalt salt, manganese salt products, as well as lithium carbonate or lithium hydroxide products have higher purity and better quality, which is superior to products produced by traditional processes. It can better meet the demand of the high-end market for high-quality battery materials, and improve the market competitiveness and added value of the products.

[0025] Stable Product Performance: Due to its low impurity content, the product exhibits more stable and reliable performance. For example, lithium hydroxide produced using this process can significantly improve battery charge-discharge performance, cycle life, and safety when used in battery manufacturing, providing a higher-quality battery material guarantee for new energy vehicles, electronic devices, and other fields, and contributing to the development and upgrading of related industries.

[0026] In summary, this technology has significant advantages in terms of resource recycling, environmental protection costs, and product quality, and has broad application prospects and market value. Attached Figure Description

[0027] Figure 1 is a process flow diagram of the present invention.

[0028] Figure 2 is a schematic diagram of bipolar membrane electrolysis of lithium chloride. Detailed Implementation

[0029] For the purposes of the detailed description below, it should be understood that the invention may take various alternative variations and sequences of steps unless expressly stated otherwise. Furthermore, except in any operational instance, or otherwise indicated, all figures representing the amounts of ingredients used, for example, in the specification and claims, should be understood to be modified in all cases by the term “about.” Therefore, unless indicated to the contrary, the numerical parameters set forth in the following specification and appended claims are approximations varying with the desired performance to be obtained according to the invention. It is not at all an attempt to limit the application of the doctrine of equivalents to the scope of the claims; each numerical parameter should be interpreted at least according to the number of significant figures reported and by applying ordinary rounding techniques.

[0030] Although the numerical ranges and parameters illustrating the broad scope of the invention are approximate, the values ​​listed in the specific examples are reported as precisely as possible. However, any numerical value inherently contains some error that is necessarily caused by the standard deviation found in their respective test measurements.

[0031] Furthermore, it should be understood that any numerical range described herein is intended to include all subranges falling within it. For example, the range “1 to 10” is intended to include all subranges between the minimum value 1 and the maximum value 10, i.e., a minimum value equal to or greater than 1 and a maximum value equal to or less than 10.

[0032] Example 1:

[0033] Experimental materials and equipment: Prepare ternary battery cathode material powder, select sulfuric acid as dissolving acid, and equip with solid-liquid separation equipment, liquid separation device, extraction equipment, electrolysis equipment, ternary battery cathode recycled material powder, 15% dilute sulfuric acid, stirred reaction vessel, nanofiltration filtration system, bipolar membrane stack, extraction system, lithium precipitation reaction vessel, lithium precipitation filter, etc.

[0034] Process steps:

[0035] Following step 1) of the new process described above, the ternary lithium battery cathode recovery material powder is dissolved in a 15% dilute sulfuric acid solution at a ratio of L:S = 5:1. The reaction temperature and time are controlled, and after the material is fully dissolved, it is pressed into a plate and frame for solid-liquid separation. The activated carbon powder undergoes two countercurrent washes to ensure the leaching rate. The equipment operation and actual operation process are recorded, and the weight of the activated carbon powder and the volume of the leachate are accurately weighed and sampled for analysis. This ensures the material is fully dissolved before solid-liquid separation, yielding activated carbon powder and leachate. In this step, precise control of the dissolution conditions ensures more complete dissolution of valuable metals, laying the foundation for a high recovery rate and demonstrating the advantage of high valuable metal recovery. Simultaneously, the amount of washing water must be strictly controlled to ensure the recovery rate while preventing liquid expansion.

[0036] The leachate is pumped into a nanofiltration system using a high-pressure pump to separate lithium from other divalent metals. Simultaneously, the equipment operation and procedures are recorded, and the volumes of the dilute and concentrated solutions are accurately recorded and samples are taken for analysis.

[0037] Analysis of experimental results: Analysis and calculation of valuable metals such as lithium, nickel, cobalt, and manganese in activated carbon powder, leachate, and washing water show that the leaching rate of valuable metals is 95%.

[0038] Analysis and comparison of the dilute and concentrated solutions of the leachate after passing through the nanofiltration system revealed that approximately 90% of lithium and other divalent metals were intercepted in the concentrated solution by the nanofiltration membrane, indicating that the nanofiltration system did not effectively separate lithium and other divalent metals.

[0039] The experiment did not achieve effective separation of lithium from other divalent metals, did not achieve the expected results, and there was no need to continue extraction and bipolar membrane electrolysis.

[0040] Example 2:

[0041] Experimental materials and equipment: Take another portion of ternary battery cathode material powder. This time, 15% hydrochloric acid was selected as the dissolving acid. Other equipment is the same as in Example 1.

[0042] Process steps:

[0043] The same process of dissolving the cathode material powder was performed. After adding 15% hydrochloric acid, the ternary cathode material powder was added to the 15% hydrochloric acid solution at an L:S ratio of 5:1. Reaction parameters, such as temperature and stirring speed, were precisely controlled to ensure complete dissolution of the cathode material powder. The solution was then pressed into a plate and frame for solid-liquid separation, undergoing two countercurrent cycles. The amount of washing water was strictly controlled to ensure the leaching rate and prevent liquid expansion. The equipment operation and actual operation process were recorded, and the weight of the activated carbon powder and the volume of the leachate were accurately measured, with samples taken for analysis.

[0044] The leachate is pumped into a nanofiltration system, and the equipment operation and process are recorded simultaneously. The volumes of dilute and concentrated solutions are accurately recorded and samples are taken for analysis. A liquid separation device is used to separate the leachate. This device can accurately separate lithium salt solutions from nickel, cobalt, and manganese metal salts, achieving excellent separation results and ensuring the purity of each metal salt. This provides high-quality raw materials for subsequent processing, demonstrating the advantage of high precision in metal separation.

[0045] This experiment used hydrochloric acid leaching, and the entire system was a chloride salt system. Based on actual production conditions and experience, the chloride salt system extraction process generates a large amount of hydrogen chloride gas and chlorine gas, which will seriously affect the air quality in the production area and cause severe equipment corrosion. Therefore, this experiment only explored the separation of lithium and other divalent metals in the chloride salt system by nanofiltration membranes, and thus did not involve the extraction and electrolysis of metallic chloride salts.

[0046] Experimental results analysis: Data analysis showed that the leaching rate of the ternary cathode material powder was 96%.

[0047] Analysis of the dilute and concentrated solutions obtained using nanofiltration membranes revealed that in the chloride salt system, over 95% of lithium chloride was not intercepted by the nanofiltration membrane and entered the dilute solution, while other divalent and high-valence metals were completely intercepted by the nanofiltration membrane. Therefore, it can be concluded that effective separation of lithium and other divalent and high-valence metals can be achieved in the chloride salt system.

[0048] Example 3:

[0049] Experimental materials and equipment: Ternary battery cathode material powder was selected, and a mixed acid was used for dissolving it (the amount of hydrochloric acid was 1.2 times the theoretical amount of lithium in the ternary cathode material powder, and the remainder was sulfuric acid). The equipment was the same as in the previous two examples.

[0050] Process steps:

[0051] To dissolve the cathode material powder, the ternary cathode material powder was added to the mixed acid at a ratio of L:S = 5:1. Based on the characteristics of this batch of material powder, the dissolution conditions, including temperature, acidity, and reaction time, were precisely adjusted. The solid-liquid separation and nanofiltration membrane separation of lithium and other divalent metals in Experiments 1 and 2 were repeated.

[0052] The leaching rate of valuable metals in this experiment was 95%. The concentrated solution after nanofiltration was a sulfate solution of high-value metals such as nickel, cobalt, and manganese, while the dilute solution was a lithium chloride solution.

[0053] The leachate is separated by a liquid separation device, which, with its high-precision separation performance, accurately separates lithium salt solution from nickel, cobalt, and manganese metal salts. The separated metal salt solutions are of high purity, providing a good foundation for subsequent extraction, back-extraction, and lithium salt processing steps, demonstrating the advantage of high precision in metal separation.

[0054] After extraction, nickel-cobalt separation, and back-extraction of the nanofiltration membrane concentrate (a sulfate solution of high-valence metals such as nickel, cobalt, and manganese), nickel sulfate and cobalt sulfate solutions are obtained. Further processing of the nickel sulfate and cobalt sulfate solutions yields related nickel and cobalt products.

[0055] Since the industrial production process of sulfate extraction of nickel and cobalt is very mature, it will not be described in detail in this invention.

[0056] The lithium content in the nanofiltration membrane distillate (lithium chloride solution) is low (the lithium content and the lithium content in the ternary cathode material powder are related to the solid-liquid ratio of the leachate; in this experiment, the lithium content was 4 g / L), making it unsuitable for direct production of lithium carbonate. This experiment uses a bipolar membrane electrolysis method to produce lithium carbonate or lithium hydroxide: the lithium chloride solution (nanofiltration membrane distillate) is pumped into the bipolar membrane stack, and under the action of a DC electric field, lithium hydroxide solution is produced and enriched in the anode chamber, while hydrochloric acid solution is produced and enriched in the cathode chamber.

[0057] Bipolar membrane electrolysis generates a lithium hydroxide solution, which is pumped into a lithium precipitation reactor. The temperature is controlled at 80℃-90℃, and carbon dioxide gas is introduced to maintain a constant pressure within the reactor. The final pH value is controlled to prevent excessive carbon dioxide from forming lithium bicarbonate. After the reaction is complete, the lithium carbonate is separated through a lithium precipitation filter, dried, and crushed to obtain battery-grade lithium carbonate. The lithium carbonate mother liquor is recycled. The lithium hydroxide solution can also be evaporated and crystallized using an MVR evaporator to produce lithium hydroxide monohydrate. Due to strict impurity control throughout the process, traditional chemical impurity removal methods are not used, avoiding the introduction of impurities. The produced lithium hydroxide monohydrate and lithium carbonate products have high purity and excellent quality, exhibiting superior performance in battery applications, such as high charge-discharge efficiency, long cycle life, and good safety. This highlights the excellent product quality, better meeting the demands of the high-end market and enhancing the product's market competitiveness and added value.

[0058] Example 4:

[0059] Raw materials and equipment: Raffinate from the extraction in Example 3, P204 extractant, P507 extractant, bipolar membrane stack, purification reactor, and extractant saponification tank.

[0060] Process steps:

[0061] The raffinate (sodium sulfate solution) after extracting the nanofiltration membrane concentrate in Example 3 was purified and then electrolyzed using a bipolar membrane stack. Under the action of a DC electric field, sodium hydroxide solution was produced and enriched in the anode chamber, and sulfuric acid solution was produced and enriched in the cathode chamber.

[0062] The produced sodium hydroxide solution is saponified with the unloaded organic phases (P507, P204) according to the required saponification rate. After the organic phases are saponified, they enter the extraction process.

[0063] The resulting sulfuric acid solution is mixed with the hydrochloric acid solution produced by lithium chloride electrolysis in Example 3 to jointly deacidify the ternary cathode material powder.

[0064] The above experiments can prove that:

[0065] 1. The nanofiltration membrane used in this invention can effectively separate lithium and other divalent high-valence metals in the leaching solution of ternary cathode material powder, perfectly solving the difficulty of completely separating lithium from other metals in traditional processes, and thus greatly reducing the consumption of auxiliary materials for separating lithium from other metal ions in traditional processes.

[0066] 2. The method for preparing lithium hydroxide and lithium carbonate from lithium chloride via bipolar membrane stack electrolysis in this invention differs from traditional lithium carbonate and lithium hydroxide production processes. It eliminates the need for auxiliary materials such as sodium carbonate, sodium hydroxide, and lime. Carbon dioxide, compared to sodium carbonate, does not introduce impurity metal ions, thus improving the quality of the lithium carbonate product. Lithium hydroxide is obtained entirely through electrolysis, without the use of auxiliary materials such as sodium hydroxide or lime. It also eliminates processes such as causticization and freezing for sodium removal, significantly shortening the process flow and avoiding the introduction of impurities, thereby improving product quality. Furthermore, it eliminates intermediate products such as sodium sulfate decahydrate, greatly increasing the direct yield of the product.

[0067] 3. The raffinate from the extraction of divalent metals such as nickel and cobalt can be used to prepare sulfuric acid and sodium hydroxide solutions via bipolar membrane electrolysis after simple treatment. The sulfuric acid solution, combined with the hydrochloric acid solution obtained from the electrolysis of lithium chloride, serves as the acid for the acidolysis of ternary cathode material powder, achieving acid recycling and reducing the cost of purchasing sulfuric and hydrochloric acid as auxiliary materials, while also reducing the risk of introducing impurities. Sodium hydroxide can be directly saponified with the extraction organic phase, eliminating the cost of purchasing sodium hydroxide salt as an auxiliary material, and similarly reducing the risk of introducing impurities.

[0068] In summary, this invention effectively separates and recovers valuable metals such as lithium, nickel, and cobalt during the recycling of ternary cathode material powder. In the preparation of lithium hydroxide and lithium carbonate, auxiliary materials such as sodium carbonate and sodium hydroxide are no longer used, significantly reducing auxiliary material costs and improving product quality. The acid used for leaching and the alkali used for saponification are generated through a system recycling process, truly achieving resource recycling and reducing brine discharge. Therefore, it has unparalleled advantages in cost savings, improved product quality, and reduced pollution emissions.

[0069] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications 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 novel process for the comprehensive recovery of valuable metals from ternary cathode material powder, characterized in that, Specifically, the following steps are included: 1) Dissolving the positive electrode material powder: The ternary battery positive electrode material powder is slurried, then acid is added for acid hydrolysis. After the reaction is complete, solid-liquid separation is performed to obtain activated carbon powder and leachate. The activated carbon powder needs to be washed 2-3 times in countercurrent to ensure the leaching rate. 2) Separation of metal salt solutions: The leachate is passed through a liquid separation device to separate lithium salt solutions and nickel, cobalt, and manganese metal salt solutions; 3) Extraction and Back-extraction: The separated nickel, cobalt, and manganese metal salts are extracted to obtain nickel and cobalt salts. The sodium salt raffinate is passed through a saponified extractant and then enters an electrolysis device to obtain sodium hydroxide and acid. The solution is then extracted with a saponified P204 extractant organic solution. The nickel, cobalt, and other metal ions will replace the sodium ions in the extractant and enter the organic phase. The replaced sodium ions enter the raffinate. This process is called extraction. The saturated organic phase is back-extracted with a sulfuric acid solution of a certain concentration to obtain nickel sulfate and sulfuric acid solution. After passing through a P507 to separate nickel sulfate and cobalt sulfate, the nickel sulfate and sulfuric acid solution are evaporated and crystallized to obtain nickel sulfate and cobalt sulfate products. Alternatively, nickel sulfate and cobalt sulfate can be processed into nickel oxide and cobalt oxide. The empty organic phase is then acid-washed and re-saponified. 4) Treatment of raffinate: In traditional processes, raffinate can only be discharged externally. In this invention, the raffinate is electrolyzed through a bipolar membrane to regenerate sulfuric acid solution and sodium hydroxide solution. 5) Lithium salt treatment: The separated lithium salt solution is electrolyzed through a bipolar membrane to produce hydrochloric acid solution and lithium hydroxide solution. The lithium hydroxide solution is then evaporated and crystallized to produce lithium hydroxide monohydrate product.

2. The novel process for comprehensively recovering valuable metals from ternary cathode material powder according to claim 1, characterized in that: The sulfuric acid solution obtained from electrolysis in step 4) is used for the acidolysis of the positive electrode material powder in the first stage of 1), and the sodium hydroxide solution obtained from electrolysis is used for the saponification of the empty organic phase in step 3).

3. A novel process for the comprehensive recovery of valuable metals from ternary cathode material powder according to claim 1, characterized in that: The hydrochloric acid solution obtained by electrolysis in step 5) is used for 1) acid hydrolysis of positive electrode material powder. The lithium hydroxide solution obtained by electrolysis can be prepared into lithium hydroxide monohydrate solution by evaporation and crystallization, or lithium carbonate can be prepared by passing carbon dioxide through it. The prepared lithium hydroxide monohydrate or lithium carbonate can be used to prepare battery-grade products after slight treatment.

4. A novel process for the comprehensive recovery of valuable metals from ternary cathode material powder according to claim 1, characterized in that: The acid used in step 1) for acid hydrolysis is a mixture of sulfuric acid and hydrochloric acid obtained from electrolysis in steps 4) and 5).

5. A novel process for the comprehensive recovery of valuable metals from ternary cathode material powder according to claim 1, characterized in that: The salt solution in step 2) contains SO4. 2- Cl - Li + Ni 2+ Co 2+ A plasma solution; this solution can be filtered through a nanofiltration membrane to remove Cl... - Li + With SO4 2- Ni 2+ Co 2+ Effective separation yields LiCl solution and sulfate solutions of other metals.

6. A novel process for the comprehensive recovery of valuable metals from ternary cathode material powder according to claim 1, characterized in that: The salt solution to be separated in step 2) is a lithium chloride solution and other sulfate solutions.

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