A method for separating and recovering ternary battery materials

Abstract

This invention provides a method for separating and recycling ternary battery materials, comprising the following steps: (1) leaching the ternary battery materials with a leaching agent to obtain a leachate; (2) mixing the leachate with a first extraction system, and after extraction and separation, obtaining a first organic phase loaded with nickel, cobalt, copper, zinc and iron and a first raffinate; performing a first back-extraction on the first organic phase to obtain a first back-extraction solution containing nickel, cobalt, copper, zinc and iron; (3) purifying the first back-extraction solution using a second extraction system to obtain a second raffinate solution containing nickel and cobalt; performing a first pyrolysis on the second raffinate solution to recover oxides containing nickel and cobalt and a first acid reagent. The method for separating and recycling battery materials provided by this invention achieves efficient recovery of high-value materials, while also recovering a large amount of acid for recycling, reducing acid consumption and waste emissions, and making the process clean and green.

Description

Technical Field

[0001] This invention relates to the field of battery material recycling technology, and in particular to a method for separating and recycling ternary battery materials. Background Technology

[0002] As the application of batteries expands, the demand for battery materials in the new energy industry is increasing, leading to a serious shortage of resources. Waste batteries contain a large amount of valuable metals, such as lithium, cobalt, and nickel. These metals are important raw materials for manufacturing new batteries. By recycling these materials from waste batteries, the mining of new mineral resources can be reduced, thereby lowering raw material costs and alleviating the resource shortage problem.

[0003] Battery material recycling technology is a series of methods developed to recycle and reuse high-value metals from waste batteries. It mainly uses physical, chemical and biological means to extract metal materials and reuse them, thereby reducing waste and pollution.

[0004] Due to the low recovery rate of physical recycling technologies and the slow recovery rate of biological recycling technologies, chemical methods are generally preferred for recycling battery materials. Chemical recycling technologies mainly include wet recycling and dry recycling. Dry recycling, which uses mechanical sorting and high-temperature decomposition pyrolysis without the use of solutions or other media, is simple to process, easy to operate, and reduces the generation of waste liquid and residue. However, its low recovery rate, high equipment requirements, and high processing costs hinder its application in battery material recycling. Wet recycling technology, with its advantages of high recovery rate, high metal purity, and low operating temperature, is widely used in the current battery recycling field.

[0005] Existing wet recycling technologies for ternary materials generally employ leaching with sulfuric acid and hydrochloric acid, followed by extraction and separation of the leachate using phosphorus-based extractants (such as P204 and P507) to obtain cobalt and nickel salts. For example, existing technology CN107267759A discloses a comprehensive recycling method for lithium-ion battery cathode materials. This method involves high-temperature pretreatment of lithium iron phosphate and ternary battery cathode materials; slurry treatment in water; addition of concentrated sulfuric acid and hydrogen peroxide, followed by filtration to remove insoluble matter; addition of iron powder, followed by filtration to remove copper, and heating to generate iron-aluminum alum slag; addition of calcium chloride solution, followed by filtration to remove phosphate ions; countercurrent extraction using extractant P204 to remove Fe and Ca impurities; and countercurrent extraction using extractant P507 to separate Ni, Co, and Mn elements from Li elements; back-extraction of the organic phase with sulfuric acid to obtain a Ni, Co, and Mn solution, achieving the recovery of nickel, cobalt, and manganese; concentration of the aqueous phase, followed by the addition of saturated sodium carbonate solution to generate lithium carbonate precipitate, thus achieving the recycling of ternary cathode materials. However, existing technologies only use phosphorus-based extractants P204 and P507 to extract nickel and cobalt, which have poor impurity separation capabilities, long production processes, and consume a large amount of acid and alkali reagents during the extraction process, resulting in high costs.

[0006] Therefore, in view of the shortcomings of the existing technology, it has become an urgent problem to solve the problem of providing a battery material recycling method with low acid and alkali consumption, high impurity separation capability and short process flow. Summary of the Invention

[0007] To address the aforementioned technical problems, the present invention aims to provide a method for separating and recycling ternary lithium battery materials. This method, by controlling the separation and recycling process and employing an extraction process combined with back-extraction and purification processes to enhance separation, achieves highly efficient separation between impurity materials and high-value materials in battery materials, significantly shortening the process flow. Furthermore, the method also recovers the acid reagent consumed during battery material leaching, significantly reducing acid consumption in the process, enabling the recycling of the leaching agent, and further reducing waste emissions, making the process clean and environmentally friendly.

[0008] To achieve this objective, the present invention adopts the following technical solution:

[0009] In a first aspect, the present invention provides a method for separating and recycling ternary battery materials, the method comprising the following steps:

[0010] (1) The ternary battery material is leached with a leaching agent to obtain a leachate; the leaching agent includes an acid and a metal salt;

[0011] (2) The leachate is mixed with the first extraction system. After extraction and separation, a first organic phase loaded with nickel, cobalt, copper, zinc and iron and a first raffinate are obtained. The first organic phase is subjected to a first back-extraction. After separation, a first back-extraction solution containing nickel, cobalt, copper, zinc and iron is obtained.

[0012] (3) The first back-extraction liquid is purified by a second extraction system of the same type as the first extraction system to obtain a second raffinate containing nickel and cobalt. The second raffinate is subjected to a first pyrolysis to recover oxides containing nickel and cobalt and a first acid reagent.

[0013] The method for separating and recycling battery materials provided by this invention employs an extraction system to extract the leachate obtained by treating a specific component leaching agent, and combines back-extraction and purification processes to regulate the separation and recycling process, enhance separation methods, and efficiently separate nickel and cobalt from battery materials. This achieves efficient separation between impurity materials and high-value materials in battery materials, and simple purification and recycling yields nickel and cobalt salts. Then, through a pyrolysis process, high-purity and high-recovery-rate nickel-cobalt oxides are recovered. Simultaneously, acid is also recovered and can be returned to step (1) as a leaching agent, reducing acid consumption in the process, realizing the recycling of the leaching agent, and reducing waste emissions. The process operation is clean and green. Furthermore, the separation and recycling method provided by this invention uses acid combined with metal salts as leaching agents, which has the advantages of high leaching efficiency and low acid consumption.

[0014] Preferably, the acid in the leaching agent in step (1) includes hydrochloric acid.

[0015] Preferably, the metal salt in the leaching agent in step (1) includes a metal chloride.

[0016] Preferably, the metal chloride includes any one or a combination of at least two of manganese chloride, calcium chloride, magnesium chloride, or aluminum chloride.

[0017] Preferably, in the leaching agent described in step (1), the concentration of the acid is 1-6 mol / L, such as 1 mol / L, 2 mol / L, 3 mol / L, 4 mol / L, 5 mol / L, or 6 mol / L.

[0018] Preferably, in the leaching agent described in step (1), the concentration of the metal salt is 1-4 mol / L, for example, 1 mol / L, 2 mol / L, 3 mol / L or 4 mol / L.

[0019] Preferably, the total concentration of anions in the leaching agent in step (1) is 5 mol / L or more, such as 5 mol / L, 5.5 mol / L, 6 mol / L, 6.5 mol / L, 7 mol / L, 7.5 mol / L, 8 mol / L, 8.5 mol / L, 9 mol / L, 9.5 mol / L or 10 mol / L.

[0020] In this invention, the total concentration of anions in the leaching agent is controlled to be above 5 mol / L, so as to control the total concentration of anions in the leaching solution to be above 5 mol / L, thereby improving the extraction effect of the leaching solution in the subsequent step (2), so as to achieve complete leaching of nickel, cobalt, copper and zinc in the leaching solution by the extraction system.

[0021] Preferably, the mass ratio of the ternary battery material to the volume of the leachate in step (1) is 1g:(1-20)L, for example, 1g:1L, 1g:2L, 1g:4L, 1g:6L, 1g:8L, 1g:10L, 1g:12L, 1g:14L, 1g:16L, 1g:18L or 1g:20L, etc.

[0022] Preferably, the metal elements leached from the leachate in step (1) include nickel, cobalt, copper, zinc, lithium, manganese, iron, magnesium, aluminum and calcium.

[0023] Preferably, the non-metallic elements leached from the leachate in step (1) include silicon.

[0024] In this invention, the leached non-metallic element silicon does not affect the recovery effect of metallic elements.

[0025] Preferably, the first extraction system in step (2) and the second extraction system in step (3) are independently selected from nitrogen heterocyclic extractants.

[0026] Preferably, the nitrogen heterocyclic extractant comprises a diluent and a nitrogen-containing heterocyclic amide compound.

[0027] This invention employs a specific nitrogen heterocyclic extractant as the first extraction system to extract the leachate and a second extraction system to purify the first back-extraction solution containing nickel, cobalt, copper, zinc, and iron. The extraction order of metal ions in the acid leachate of battery materials by the nitrogen heterocyclic extractant is: Cu(II)>Zn(II)>Fe(III)>Ni(II)>Co(II)>>Mn(II)≈Ca≈Al≈Cr(III)≈Mg. Based on the extraction order, efficient extraction of copper, zinc, nickel, and cobalt in the leachate is achieved, separating other metal substances. The nitrogen heterocyclic extractant has a large extraction capacity and good separation effect for copper, zinc, nickel, and cobalt in battery materials, which can improve the recovery rate of copper, zinc, nickel, and cobalt materials.

[0028] It should be noted that during the extraction of the leachate using a specific nitrogen heterocyclic extractant, metallic iron in the leachate will also be extracted. The iron in the leachate originates from iron introduced by component contamination during the acquisition of ternary battery materials, and its content is only a very small amount. It can be chosen not to treat it, which has a low impact on the recovery rate of nickel, cobalt, copper and zinc and the recovered nickel and cobalt oxides. Alternatively, it is advisable to use an iron extractant in the prior art to extract and remove the iron in the leachate.

[0029] Preferably, the nitrogen-containing heterocyclic amide compound includes N-octylquinoline-8-carboxamide, N-isooctylquinoline-8-carboxamide, N,N-di(octyl)quinoline-8-carboxamide, N,N-di(isooctyl)quinoline-8-carboxamide, N-octylisoquinoline-8-carboxamide, N-isooctylisoquinoline-8-carboxamide, N,N-di(octyl)isoquinoline-8-carboxamide, N,N-di(isooctyl)isoquinoline-2-carboxamide, N-dodecylquinoline-8-carboxamide, N,N-bis(octyl)quinoline-8-carboxamide, etc. (Dodecyl)quinoline-8-carboxamide, N-dodecylisoquinoline-8-carboxamide, N,N-bis(dodecyl)isoquinoline-8-carboxamide, N-octyl-1H-pyrrole-2-carboxamide, N-isooctyl-1H-pyrrole-2-carboxamide, N,N-bis(octyl)-1H-pyrrole-2-carboxamide, N,N-bis(isooctyl)-1H-pyrrole-2-carboxamide, N-dodecyl-1H-pyrrole-2-carboxamide, N,N-bis(dodecyl)-1H-pyrrole-2-carboxamide N-C(Octyl)-1H-pyrrole-3-carboxamide, N-Isooctyl-1H-pyrrole-3-carboxamide, N,N-Di(Octyl)-1H-pyrrole-3-carboxamide, N,N-Di(Isooctyl)-1H-pyrrole-3-carboxamide, N-Dodecyl-1H-pyrrole-3-carboxamide, N,N-Bis(Dodecyl)-1H-pyrrole-3-carboxamide, N-Octylpyridine-3-carboxamide, N-Isooctylpyridine-3-carboxamide, N,N-Di(Octyl)pyridine-3-carboxamide The amide, N,N-di(isooctyl)pyridine-3-carboxamide, N-octylpyridine-4-carboxamide, N-isooctylpyridine-4-carboxamide, N,N-di(octyl)pyridine-4-carboxamide, N,N-di(isooctyl)pyridine-4-carboxamide, N-dodecylpyridine-3-carboxamide, N-dodecylpyridine-4-carboxamide, N,N-bis(dodecyl)pyridine-3-carboxamide or N,N-bis(dodecyl)pyridine-4-carboxamide, any one or a combination of at least two of them.

[0030] Preferably, the diluent comprises any one or a combination of at least two of C7-C20 hydrocarbons, liquid ketones, or liquid alcohols.

[0031] Preferably, in step (2), the volume percentage of the nitrogen-containing heterocyclic amide compound in the first extraction system is 5-50 vol%, such as 5 vol%, 10 vol%, 15 vol%, 20 vol%, 25 vol%, 30 vol%, 35 vol%, 40 vol%, 45 vol%, or 50 vol%, and more preferably 10-40 vol%.

[0032] Preferably, in step (3), the volume percentage of the nitrogen-containing heterocyclic amide compound in the second extraction system is 5-50 vol%, such as 5 vol%, 10 vol%, 15 vol%, 20 vol%, 25 vol%, 30 vol%, 35 vol%, 40 vol%, 45 vol%, or 50 vol%, and more preferably 10-40 vol%.

[0033] Preferably, the volume ratio of the leachate in step (2) to the first extraction system is 1:(1-10), such as 1:1, 1:2, 1:4, 1:6, 1:8 or 1:10.

[0034] The present invention regulates the volume ratio of the leachate and the first extraction system. On the one hand, it can improve the efficient and complete extraction of copper, zinc, nickel and cobalt in the leachate and increase the recovery rate of nickel and cobalt metal elements. On the other hand, regulating the volume ratio of the leachate and the extraction system can also effectively prevent other impurities from being mixed into the organic phase obtained by extraction and improve the purity of the recovered material.

[0035] Preferably, the stripping solvent used in step (2) includes water and / or acid, and the concentration of the acid is 0.1-1 mol / L, such as 0.1 mol / L, 0.2 mol / L, 0.3 mol / L, 0.4 mol / L, 0.5 mol / L, 0.6 mol / L, 0.7 mol / L, 0.8 mol / L, 0.9 mol / L or 1 mol / L.

[0036] Preferably, the acid used in the first back-extraction step (2) includes hydrochloric acid.

[0037] The present invention introduces dilute acid and water into the stripping solvent used in the first stripping process, which can control the concentration of anions (chloride ions) in the first stripping solution obtained from the first stripping process. This is beneficial for the extraction of copper, zinc and iron by the nitrogen heterocyclic extractant in the subsequent purification process, while avoiding the extraction of nickel and cobalt, thereby achieving the separation and recovery of nickel and cobalt materials.

[0038] Preferably, in the first back-extraction process in step (2), the volume ratio of the first organic phase to the back-extraction solvent used in the first back-extraction is (1-30):1, for example, 1:1, 2:1, 4:1, 6:1, 8:1, 10:1, 12:1, 14:1, 16:1, 18:1, 20:1, 22:1, 24:1, 26:1, 28:1 or 30:1, etc.

[0039] Preferably, the temperature of the first back-extraction in step (2) is 10-70°C, such as 10°C, 20°C, 30°C, 40°C, 50°C, 60°C or 70°C.

[0040] Preferably, the total concentration of anions in the first back-extraction solution in step (2) is less than 4 mol / L, such as 4 mol / L, 3.5 mol / L, 3 mol / L, 2.5 mol / L, 2 mol / L, 1.5 mol / L or 1 mol / L.

[0041] This invention utilizes a nitrogen heterocyclic extractant to extract an organic phase loaded with nickel, cobalt, copper, zinc, and iron. Since copper, zinc, and iron are extracted preferentially over nickel and cobalt, the first back-extraction solution still contains a certain amount of copper, iron, and zinc, necessitating secondary purification. By controlling the chloride ion concentration in the first back-extraction solution to a low level (≤4 mol / L), a specific nitrogen heterocyclic extractant can efficiently remove copper and zinc with minimal loss of nickel and cobalt. Based on this characteristic, this invention employs a second extraction system of the same type as the first extraction system—a nitrogen heterocyclic extractant—to perform a secondary extraction purification of the first back-extraction solution, enabling the recovery of high-purity nickel and cobalt products.

[0042] Preferably, in the purification process described in step (3), the volume ratio of the first back-extraction liquid to the second extraction system is (1-20):1, for example, 1:1, 2:1, 4:1, 6:1, 8:1, 10:1, 12:1, 14:1, 16:1, 18:1 or 20:1, etc.

[0043] In this invention, if the volume ratio (O / A) of the first back-extraction solution and the second extraction system is too small, it is impossible to completely remove copper, zinc and iron from the first back-extraction solution, thereby reducing the purity of nickel and cobalt; if the volume ratio is too large, it will result in a large loss of nickel and cobalt, thereby reducing the nickel and cobalt recovery rate in the material.

[0044] Preferably, the temperature of the first pyrolysis in step (3) is 600-800℃, such as 600℃, 620℃, 640℃, 660℃, 680℃, 700℃, 720℃, 740℃, 760℃, 780℃ or 800℃.

[0045] Preferably, the time for the first pyrolysis in step (3) is 2-4 hours, such as 2 hours, 2.5 hours, 3 hours, 3.5 hours or 4 hours.

[0046] Preferably, the type of the first acid reagent recovered in step (3) is the same as the type of acid in the leaching agent described in step (1).

[0047] Preferably, after the second raffinate is subjected to a first pyrolysis, the first acid reagent recovered in step (3) is returned to step (1) for use as a leaching agent.

[0048] In the process of recycling nickel and cobalt materials in battery materials, the present invention also recovers acid reagents, which can be returned to step (1) along with the acids generated in the recycling process of other substances and continue to be used as leaching agents, further reducing acid consumption and waste discharge in the process.

[0049] Preferably, after the purification treatment in step (3), a second organic phase containing iron, copper and zinc is also obtained.

[0050] Preferably, the method for separating and recovering ternary battery materials further includes step (4), specifically including performing a second back-extraction on the second organic phase containing copper, zinc and iron obtained after the purification treatment to obtain a second back-extraction solution containing copper, zinc and iron, and then performing a second pyrolysis to recover oxides and a second acid reagent containing copper, zinc and iron.

[0051] Preferably, the stripping reagent used in step (4) for the second stripping includes water and / or acid, wherein the concentration of the acid is 0.1-1 mol / L, such as 0.1 mol / L, 0.2 mol / L, 0.3 mol / L, 0.4 mol / L, 0.5 mol / L, 0.6 mol / L, 0.7 mol / L, 0.8 mol / L, 0.9 mol / L or 1 mol / L, etc.

[0052] Preferably, the acid used in the second back-extraction step (4) includes hydrochloric acid.

[0053] Preferably, in the second back-extraction process in step (4), the volume ratio of the second organic phase to the back-extraction solvent used in the second back-extraction is (1-10):1, for example, 1:1, 2:1, 4:1, 6:1, 8:1 or 10:1.

[0054] Preferably, the temperature of the second back-extraction in step (4) is above 50°C, such as 50°C, 52°C, 54°C, 56°C, 58°C or 60°C.

[0055] Preferably, the temperature of the second pyrolysis in step (4) is 600-800℃, such as 600℃, 620℃, 640℃, 660℃, 680℃, 700℃, 720℃, 740℃, 760℃, 780℃ or 800℃.

[0056] Preferably, the second pyrolysis time in step (4) is 2-4 hours, such as 2 hours, 2.5 hours, 3 hours, 3.5 hours or 4 hours.

[0057] Preferably, the type of the second acid reagent recovered in step (4) is the same as the type of acid in the leaching agent described in step (1).

[0058] Preferably, after the second back-extraction solution is subjected to a second pyrolysis, the recovered second acid reagent is returned to step (1) for use in the leaching process.

[0059] This invention can extract a mixed solution containing copper and zinc from an organic solvent, achieving efficient recovery of copper and zinc. At the same time, the acid obtained from the recovery process can be recycled together with the acid generated in the recovery process of other substances and reused in step (1), thereby improving the recycling rate of acid and reducing the amount of waste.

[0060] Preferably, the metal elements in the first raffinate obtained in step (2) include lithium, manganese, magnesium, aluminum and calcium.

[0061] Preferably, the method for separating and recovering ternary battery materials further includes step (5), which specifically includes: mixing the first raffinate with the third extraction system, and after extraction and separation, obtaining a third organic phase loaded with lithium and a third raffinate.

[0062] This invention employs a third extraction system to efficiently separate lithium from the first raffinate, thereby achieving the recovery of lithium from battery materials.

[0063] Preferably, the third extraction system in step (5) includes a lithium composite extraction system.

[0064] Preferably, the lithium composite extraction system is loaded with 2.5-10.4 g / L of Fe(III), including 10-60 vol% of extractant A and 10-30 vol% of extractant B, with the remainder being diluent.

[0065] In the lithium composite extraction system of the present invention, the loading of Fe(III) is 2.5 g / L, 3 g / L, 4 g / L, 5 g / L, 6 g / L, 7 g / L, 8 g / L, 9 g / L, 10 g / L or 10.4 g / L, etc.; the volume fraction of extractant A is 10 vol%, 20 vol%, 30 vol%, 40 vol%, 50 vol%, or 60 vol%, etc.; the volume fraction of extractant A is 10-30 vol%, for example 10 vol%, 15 vol%, 20 vol%, 25 vol%, or 30 vol%, etc.

[0066] Preferably, the extractant A is a neutral phosphine extractant and / or an amide extractant.

[0067] Preferably, the extractant B is an acidic phosphine extractant.

[0068] Preferably, the neutral phosphine extractant includes any one or a combination of at least two of the following: tributyl phosphate (TBP), trisec-butyl phosphate (TsBP), tripentyl phosphate (TAP), triisoamyl phosphate (TiAP), or dimethylheptyl methyl phosphate (P350).

[0069] Preferably, the amide extractant includes any one or a combination of at least two of N,N-di(1-methylheptyl)hexamethylene (N503), N,N-di-2-ethylhexylacetamide, or N,N-diethyl-2-ethylhexylamide.

[0070] Preferably, the acidic phosphine extractant comprises any one or a combination of at least two of the following: di(2-ethylhexyl) phosphate (P204), 2-ethylhexyl phosphate mono-2-ethylhexyl ester (P507), di(2,2,4-trimethylpentyl) hypophosphite (Cyanex272), or 2-ethylhexyl hypophosphite (P229).

[0071] Preferably, the diluent comprises any one of C7-C13 hydrocarbons, water-insoluble liquid ketones, or alcohols.

[0072] Preferably, in step (5), the volume ratio of the first raffinate to the third extraction system is (1-10):1, for example, 1:1, 2:1, 4:1, 6:1, 8:1 or 10:1.

[0073] Preferably, the lithium-loaded third organic phase is subjected to a third back-extraction to obtain a lithium-containing solution.

[0074] Preferably, the extraction solvent used in the third extraction includes water.

[0075] Preferably, the volume ratio of the third organic phase to the stripping reagent used in the third stripping is (10-30):1, for example, 10:1, 12:1, 14:1, 16:1, 18:1, 20:1, 22:1, 24:1, 26:1, 28:1 or 30:1, etc.

[0076] Preferably, the metal elements in the third raffinate obtained in step (5) include manganese, magnesium, aluminum and calcium.

[0077] Preferably, the method for separating and recovering ternary battery materials further includes step (6), the specific process of which includes: performing split extraction on the third raffinate, obtaining a fourth organic phase loaded with manganese and a fourth raffinate after extraction and separation, performing a fourth back-extraction on the fourth organic phase, obtaining a manganese-containing solution after separation, and then performing a third pyrolysis on the manganese-containing solution to recover manganese oxides and a third acid reagent.

[0078] This invention uses a combination of split extraction and back-extraction and pyrolysis processes in the third raffinate to achieve partial extraction of manganese. The fourth raffinate also retains some manganese. On the one hand, manganese chloride can provide a high concentration of chloride ions to meet the chloride ion concentration requirements in the cobalt-nickel recovery process; on the other hand, it is to avoid a large amount of manganese accumulating to saturation in the water, which would affect the cyclic leaching of manganese in the battery materials.

[0079] Preferably, the metal elements in the fourth raffinate obtained in step (6) include manganese, iron, magnesium, aluminum and calcium.

[0080] Preferably, in step (6), the molar ratio of manganese in the fourth organic phase to manganese in the fourth raffinate is 1:(0.1-15), such as 1:0.1, 1:1, 1:9, 1:11, 1:13 or 1:15.

[0081] Preferably, the extractant used in step (6) for split extraction includes any one of tertiary amine extractants or quaternary ammonium salt extractants.

[0082] Preferably, the tertiary amine extractant comprises any one or a combination of at least two of trioctyldecyl tertiary amine (N235), tri-n-octylamine (TOP), or Alamine 336.

[0083] In this invention, Alamine 336 is a commercially available tertiary amine extractant.

[0084] Preferably, the quaternary ammonium salt extractant comprises trioctylmethylammonium chloride (Aliquat 336).

[0085] Preferably, the volume ratio of the third raffinate in step (6) to the extractant used in the split extraction is 1:(1-10), such as 1:1, 1:2, 1:4, 1:6, 1:8 or 1:10.

[0086] This invention regulates the volume ratio of the third raffinate to the extractant used in split extraction, thereby enabling partial extraction of manganese from the third raffinate.

[0087] Preferably, in step (6), the extraction solvent used in the fourth extraction includes water.

[0088] Preferably, in the fourth back-extraction process described in step (6), the volume ratio of the fourth organic phase to the back-extraction solvent is (1-10):1, for example, 1:1, 2:1, 4:1, 6:1, 8:1 or 10:1.

[0089] Preferably, the temperature of the third pyrolysis in step (6) is 600-800℃, such as 600℃, 620℃, 640℃, 660℃, 680℃, 700℃, 720℃, 740℃, 760℃, 780℃ or 800℃.

[0090] Preferably, the time for the third pyrolysis in step (6) is 2-4 hours, such as 2 hours, 2.5 hours, 3 hours, 3.5 hours or 4 hours.

[0091] Preferably, the type of the third acid solution recovered in step (6) is the same as the type of acid used in step (1).

[0092] Preferably, the third acid solution recovered in step (6) is returned to step (1) for the leaching process.

[0093] Preferably, the fourth raffinate recovered in step (6) is returned to step (1) for the leaching process.

[0094] It should be noted that the processing methods for obtaining ternary cathode materials to be recycled from waste batteries are all conventional technical solutions. All processing methods that can be obtained within a reasonable scope by those skilled in the art are applicable to this invention.

[0095] For example, the present invention provides a method for processing ternary cathode material to be recycled from waste batteries. The processing method includes: discharging a battery containing ternary battery material, and then sequentially crushing, disassembling, flotation and pyrolysis of the discharged battery to obtain ternary cathode material to be recycled.

[0096] Furthermore, the ternary battery material in this invention specifically refers to ternary battery materials containing different proportions of nickel, cobalt, and manganese, such as LiNi. 0.3 Co 0.3 Mn 0.3O2(NCM111), LiNi 0.5 Co 0.2 Mn 0.3 O2(NCM523), LiNi 0.6 Co 0.2 Mn 0.2 O2 (NCM622) or LiNi 0.8 Co 0.1 Mn 0.1 O2 (NCM811), etc.

[0097] Compared with the prior art, the present invention has at least the following beneficial effects:

[0098] The method for separating and recycling battery materials provided by this invention employs an extraction system to extract the leachate obtained by treating a specific component leaching agent, and combines back-extraction and purification processes to regulate the separation and recycling process, enhance separation methods, and efficiently separate nickel and cobalt from battery materials. This achieves efficient separation between impurity materials and high-value materials in battery materials, and simple purification and recycling yields nickel and cobalt salts. Then, through a pyrolysis process, high-purity and high-recovery-rate nickel-cobalt oxides are recovered. Simultaneously, acid is also recovered and can be returned to step (1) as a leaching agent, reducing acid consumption in the process, realizing the recycling of the leaching agent, and reducing waste emissions. The process operation is clean and green. Furthermore, the separation and recycling method provided by this invention uses acid combined with metal salts as leaching agents, which has the advantages of high leaching efficiency and low acid consumption. Attached Figure Description

[0099] Figure 1 This is a schematic diagram of the process flow for the method of separating and recycling ternary battery materials provided by the present invention. Detailed Implementation

[0100] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments. However, the following examples are merely simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention is determined by the claims.

[0101] In one specific embodiment, the present invention employs a lithium nickel cobalt manganese oxide (chemical formula LiNi). 0.3 Co 0.3 Mn 0.3 A lithium-ion battery is constructed using O2 as the positive electrode and graphite as the negative electrode, with lithium hexafluorophosphate as the electrolyte. After charge-discharge cycles, the cycled battery is crushed, disassembled, floated, and pyrolyzed to obtain ternary battery materials to be recycled.

[0102] The ternary battery materials to be recycled in the following embodiments and comparative examples were all obtained using the above-described processing method, and the battery composition and the type of ternary battery materials were completely identical.

[0103] In the following examples, room temperature refers to 25°C.

[0104] Example 1

[0105] This embodiment provides a method for separating and recycling ternary battery materials, and the process flow diagram is shown below. Figure 1 As shown, the specific steps include the following:

[0106] S1. At room temperature, the ternary battery material to be recycled is mixed with a leaching agent at a mass ratio of 1g:10L. The leaching agent includes 3mol / L hydrochloric acid and 2mol / L manganese chloride. The mixture is stirred for 4 hours to obtain a leachate. The leached metal elements in the leachate include nickel, cobalt, copper, zinc, lithium, manganese, iron, magnesium, aluminum and calcium. The leached non-metal elements in the leachate include silicon. The concentration of chloride ions in the leachate is 7mol / L.

[0107] S2. The leachate obtained in step S1 is subjected to three-stage countercurrent extraction with a first extraction system consisting of 20 vol% N-isooctylpyridine-3-carboxamide and kerosene at a volume ratio (A / O) of 1:3 to obtain a first organic phase loaded with nickel, cobalt, copper, zinc and iron elements and a first raffinate containing lithium, manganese, magnesium, aluminum, calcium and silicon. The first organic phase is subjected to a first back-extraction at 50°C. The back-extraction solvent used in the first back-extraction is 0.5 mol / L dilute hydrochloric acid, and the volume ratio of the first organic phase to the back-extraction solvent used in the first back-extraction is 10:1. After separation, a first back-extraction solution containing nickel, cobalt, copper, zinc and iron elements is obtained, and the concentration of chloride ions in the first back-extraction solution is 4 mol / L.

[0108] S3. The first back-extraction solution obtained in step S2 is purified by a second extraction system consisting of N-isooctylpyridine-3-carboxamide and kerosene at a volume percentage of 20 vol% under a volume ratio (A / O) of 10:1, to obtain a purified second raffinate containing nickel chloride and cobalt chloride and a second organic phase containing copper, zinc and iron. The second raffinate containing nickel chloride and cobalt chloride is pyrolyzed at 750°C for 3 hours to obtain oxides containing nickel and cobalt and hydrochloric acid. The recovered hydrochloric acid is returned to step S1 for the leaching process.

[0109] S4. At 60°C, the second organic phase containing copper, zinc and iron obtained in step S3 is subjected to a second back-extraction with water. The volume ratio of the second organic phase to water is 10:1, resulting in a second back-extraction solution containing copper, zinc and iron. The second back-extraction solution is then subjected to pyrolysis at 750°C for 3 hours to recover the oxides containing copper, zinc and iron and hydrochloric acid. The recovered hydrochloric acid is returned to step S1 for the leaching process.

[0110] S5. The first raffinate obtained in step S2 is mixed with the lithium composite extraction system at a volume ratio (A / O) of 5:1. The lithium composite extraction system is loaded with 10 g / L Fe(III) and includes 30 vol% tributyl phosphate, 20 vol% di(2-ethylhexyl) phosphate and 50 vol% kerosene. After extraction and separation, a third organic phase loaded with lithium and a third raffinate containing manganese, magnesium, aluminum, calcium and silicon are obtained. The third organic phase is subjected to a third back-extraction with pure water at a volume ratio of 15:1. A lithium chloride solution is then separated and recovered.

[0111] S6. The third raffinate obtained in step S5 is subjected to a two-stage countercurrent extraction with a volume ratio (A / O) of 1:5, consisting of an extraction system composed of a 20 vol% trioctyldecyl tertiary amine treated with 6 mol / L hydrochloric acid and kerosene. After separation, a fourth organic phase loaded with manganese and a fourth raffinate containing manganese, magnesium, aluminum, calcium and silicon are obtained. The molar ratio of manganese in the fourth organic phase to manganese in the fourth raffinate is 1:10. The fourth organic phase loaded with manganese is subjected to a fourth back-extraction with water, wherein the volume ratio of the fourth organic phase to water is 5:1. After separation, a manganese chloride solution is obtained. The manganese chloride solution is pyrolyzed at 700°C for 3 hours to obtain manganese oxide and hydrochloric acid. The recovered hydrochloric acid and the fourth raffinate are returned to the leaching process in step S1 for reuse.

[0112] Example 2

[0113] This embodiment provides a method for separating and recycling ternary battery materials, and the process flow diagram is shown below. Figure 1 As shown, the specific steps include the following:

[0114] S1. At room temperature, the ternary battery material to be recycled is mixed with a leaching agent at a mass ratio of 1g:20L. The leaching agent includes hydrochloric acid with a concentration of 3mol / L and aluminum chloride with a concentration of 2mol / L. The mixture is stirred for 5 hours to obtain a leachate. The leached metal elements in the leachate include nickel, cobalt, copper, zinc, lithium, manganese, iron, magnesium, aluminum and calcium. The leached non-metal elements in the leachate include silicon. The concentration of chloride ions in the leachate is 9mol / L.

[0115] S2. The leachate obtained in step S1 is subjected to a three-stage countercurrent extraction with a first extraction system consisting of 30 vol% N-octylquinoline-8-carboxamide and kerosene at a volume ratio (A / O) of 1:5, yielding a first organic phase loaded with nickel, cobalt, copper, zinc, and iron, and a first raffinate containing lithium, manganese, magnesium, aluminum, calcium, and silicon. The first organic phase is then subjected to a first back-extraction at 70°C, using pure water as the back-extraction solvent. The volume ratio of the first organic phase to the back-extraction solvent is 20:1. After separation, a first back-extraction solution containing nickel, cobalt, copper, zinc, and iron is obtained, with a chloride ion concentration of 3 mol / L.

[0116] S3. The first back-extraction solution obtained in step S2 is purified by a second extraction system consisting of N-octylquinoline-8-carboxamide and kerosene at a volume percentage of 40 vol% and a volume ratio (A / O) of 5:1, to obtain a purified second raffinate containing nickel chloride and cobalt chloride and a second organic phase containing copper, zinc and iron. The second raffinate containing nickel chloride and cobalt chloride is pyrolyzed at 800℃ for 2 hours to obtain oxides containing nickel and cobalt and hydrochloric acid. The recovered hydrochloric acid is returned to step S1 for the leaching process.

[0117] S4. At 65°C, the second organic phase containing copper, zinc and iron obtained in step S3 is subjected to a second back-extraction with water. The volume ratio of the second organic phase to water is 5:1, resulting in a second back-extraction solution containing copper, zinc and iron. The second back-extraction solution is then subjected to pyrolysis at 800°C for 2 hours to recover the oxides containing copper, zinc and iron and hydrochloric acid. The recovered hydrochloric acid is returned to step S1 for the leaching process.

[0118] S5. The first raffinate obtained in step S2 is mixed with the lithium composite extraction system at a volume ratio (A / O) of 2:1. The lithium composite extraction system is loaded with 10.4 g / L Fe(III) and includes 10 vol% trisec-butyl phosphate, 30 vol% 2-ethylhexyl phosphate mono-2-ethylhexyl ester and 60 vol% heptane. After extraction and separation, a third organic phase loaded with lithium and a third raffinate containing manganese, magnesium, aluminum, calcium and silicon are obtained. The third organic phase is subjected to a third back-extraction with pure water at a volume ratio of 10:1. A lithium chloride solution is then separated and recovered.

[0119] S6. The third raffinate obtained in step S5 is subjected to a two-stage countercurrent extraction with a volume ratio (A / O) of 1:10, consisting of tri-n-octylamine (20 vol%) treated with 6 mol / L hydrochloric acid and kerosene. After separation, a fourth organic phase loaded with manganese and a fourth raffinate containing manganese, magnesium, aluminum, calcium and silicon are obtained. The molar ratio of manganese in the fourth organic phase to manganese in the fourth raffinate is 1:5. The fourth organic phase loaded with manganese is subjected to a fourth back-extraction with water, wherein the volume ratio of the fourth organic phase to water is 10:1. After separation, a manganese chloride solution is obtained. The manganese chloride solution is pyrolyzed at 700°C for 3 hours to obtain manganese oxide and hydrochloric acid. The recovered hydrochloric acid and the fourth raffinate are returned to the leaching process in step S1 for reuse.

[0120] Example 3

[0121] This embodiment provides a method for separating and recycling ternary lithium battery materials, and the process flow diagram is shown below. Figure 1 As shown, the specific steps include the following:

[0122] S1. At room temperature, the ternary battery material to be recycled is mixed with a leaching agent at a mass ratio of 1g:5L. The leaching agent includes hydrochloric acid with a concentration of 4mol / L and calcium chloride with a concentration of 3mol / L. The mixture is stirred for 7 hours to obtain a leachate. The leached metal elements in the leachate include nickel, cobalt, copper, zinc, lithium, manganese, iron, magnesium, aluminum and calcium. The leached non-metal elements in the leachate include silicon. The concentration of chloride ions in the leachate is 10mol / L.

[0123] S2. The leachate obtained in step S1 is subjected to three-stage countercurrent extraction with a first extraction system consisting of 20 vol% N-dodecylpyridine-4-carboxamide and kerosene at a volume ratio (A / O) of 1:10 to obtain a first organic phase loaded with nickel, cobalt, copper, zinc and iron elements and a first raffinate containing lithium, manganese, magnesium, aluminum, calcium and silicon. At 60°C, the first organic phase is subjected to a first back-extraction with water at a volume ratio of 20:1. After separation, a first back-extraction solution containing nickel, cobalt, copper, zinc and iron elements is obtained, and the concentration of chloride ions in the first back-extraction solution is 3 mol / L.

[0124] S3. The first back-extraction solution obtained in step S2 is purified by a second extraction system consisting of N-dodecylpyridine-4-carboxamide and kerosene at a volume percentage of 20 vol% and a volume ratio (A / O) of 20:1, to obtain a purified second raffinate containing nickel chloride and cobalt chloride and a second organic phase containing copper, zinc and iron. The second raffinate containing nickel chloride and cobalt chloride is pyrolyzed at 600℃ for 4 hours to obtain oxides containing nickel and cobalt and hydrochloric acid. The recovered hydrochloric acid is returned to step S1 for the leaching process.

[0125] S4. At 60°C, the second organic phase containing copper, zinc and iron obtained in step S3 is subjected to a second back-extraction with water. The volume ratio of the second organic phase to water is 2:1, resulting in a second back-extraction solution containing copper, zinc and iron. The second back-extraction solution is then subjected to pyrolysis at 600°C for 4 hours to recover the oxides containing copper, zinc and iron and hydrochloric acid. The recovered hydrochloric acid is returned to step S1 for the leaching process.

[0126] S5. The first raffinate obtained in step S2 is mixed with the lithium composite extraction system at a volume ratio (A / O) of 10:1. The lithium composite extraction system is loaded with 9.5 g / L Fe(III) and includes 60 vol% tripentyl phosphate, 10 vol% di(2,2,4-trimethylpentyl)phosphoric acid and 30 vol% isooctyl alcohol. After extraction and separation, a third organic phase loaded with lithium and a third raffinate containing manganese, magnesium, aluminum, calcium and silicon are obtained. The third organic phase is subjected to a third back-extraction with pure water at a volume ratio of 15:1. A lithium chloride solution is then separated and recovered.

[0127] S6. The third raffinate obtained in step S5 is subjected to a two-stage countercurrent extraction with a volume ratio of 1:5 to a system consisting of 20 vol% trioctylmethylammonium chloride treated with 6 mol / L hydrochloric acid and kerosene. After separation, a fourth organic phase loaded with manganese and a fourth raffinate containing manganese, magnesium, aluminum, calcium and silicon are obtained. The molar ratio of manganese in the fourth organic phase to manganese in the fourth raffinate is 1:1. The fourth organic phase loaded with manganese is subjected to a fourth back-extraction with water, wherein the volume ratio of the fourth organic phase to water is 5:1. After separation, a manganese chloride solution is obtained. The manganese chloride solution is pyrolyzed at 600°C for 4 hours to obtain manganese oxide and hydrochloric acid. The recovered hydrochloric acid and the fourth raffinate are returned to the leaching process in step S1 for reuse.

[0128] Example 4

[0129] The only difference between this embodiment and Embodiment 1 is that in the method for separating and recovering ternary battery materials provided in this embodiment, the volume ratio of the leachate to the first extraction system consisting of 20 vol% N-isooctylpyridine-3-carboxamide and kerosene in step S2 is 2:1. All other aspects are the same as in Embodiment 1.

[0130] Example 5

[0131] The only difference between this embodiment and Embodiment 1 is that in the method for separating and recovering ternary battery materials provided in this embodiment, the volume ratio of the leachate to the first extraction system consisting of 20 vol% N-isooctylpyridine-3-carboxamide and kerosene in step S2 is 1:15. All other aspects are the same as in Embodiment 1.

[0132] Example 6

[0133] The only difference between this embodiment and Embodiment 1 is that in the method for separating and recovering ternary battery materials provided in this embodiment, during the first organic back-extraction process in step S2, the first organic phase containing nickel, cobalt, copper, zinc, and iron is back-extracted at a temperature of 10°C using 0.5 mol / L dilute hydrochloric acid. The rest of the content is the same as in Embodiment 1.

[0134] Example 7

[0135] The only difference between this embodiment and Embodiment 1 is that in the method for separating and recovering ternary battery materials provided in this embodiment, during the first organic back-extraction process in step S2, the first organic phase containing nickel, cobalt, copper, zinc, and iron is back-extracted at a temperature of 90°C using 0.5 mol / L dilute hydrochloric acid. The rest of the content is the same as in Embodiment 1.

[0136] Example 8

[0137] The only difference between this embodiment and Embodiment 1 is that in the method for separating and recovering ternary battery materials provided in this embodiment, during the first organic back-extraction process in step S2, the first organic phase containing nickel, cobalt, copper, zinc, and iron is back-extracted at a temperature of 50°C using 3 mol / L hydrochloric acid. The rest of the content is the same as in Embodiment 1.

[0138] Example 9

[0139] The only difference between this embodiment and Embodiment 1 is that in this embodiment, a method for separating and recovering ternary battery materials is provided, the concentration of manganese chloride in step S1 is adjusted to 0.75 mol / L, so that the concentration of chloride ions in the leachate is 4.5 mol / L. All other aspects are the same as in Embodiment 1.

[0140] Example 10

[0141] The only difference between this embodiment and Embodiment 1 is that in this embodiment, a method for separating and recovering ternary battery materials is provided, the volume ratio of the first organic phase to the first back-extraction solvent is adjusted to 15:1 in step S2, so that the concentration of chloride ions in the obtained first back-extraction solution is 5 mol / L. All other aspects are the same as in Embodiment 1.

[0142] Example 11

[0143] The only difference between this embodiment and Embodiment 1 is that in this embodiment, the volume ratio (A / O) of the first back-extraction solution to the second extraction system in step S3 is 1:2 in a method for separating and recovering ternary battery materials. All other aspects are the same as in Embodiment 1.

[0144] Example 12

[0145] The only difference between this embodiment and Embodiment 1 is that in this embodiment, the volume ratio (A / O) of the first back-extraction solution to the second extraction system in step S3 is 25:1 in a method for separating and recovering ternary battery materials. All other aspects are the same as in Embodiment 1.

[0146] Comparative Example 1

[0147] The only difference between this comparative example and Example 1 is that the method for separating and recovering ternary battery materials provided in this comparative example omits the addition of metal salts and uses only 3 mol / L hydrochloric acid as the leaching agent, with a leaching treatment performed at a mass ratio of ternary battery material to leaching agent of 1 g: 10 L. All other aspects are the same as in Example 1.

[0148] Comparative Example 2

[0149] The only difference between this comparative example and Example 1 is that in the method for separating and recovering ternary battery materials provided in this comparative example, water is added to the leachate to adjust the concentration of chloride ions in the leachate to 4 mol / L, step S3 is omitted, and the leachate is only extracted once using the first extraction system. All other aspects are the same as in Example 1.

[0150] The nickel- and cobalt-containing oxides, iron oxides, copper- and zinc-containing oxides, and lithium chloride separated and recovered in Examples 1-12 and Comparative Examples 1-2 were quantitatively analyzed by ICP to obtain the recovery rates of Ni, Co, Cu, Zn, and Li, and the purity of the nickel- and cobalt-containing oxides was also analyzed. The recovery rate of hydrochloric acid in the methods for separating and recovering ternary battery materials provided in Examples 1-12 and Comparative Examples 1-2 was also analyzed. The test results are shown in Table 1.

[0151] Table 1

[0152]

[0153] The test results show that:

[0154] (1) As can be seen from Examples 1 to 3, the method for separating and recycling battery materials provided by the present invention achieves efficient separation between impurity materials and high-value materials in battery materials by controlling the separation and recycling process and using extraction process combined with back-extraction process and purification process to enhance separation. The process flow is greatly shortened. At the same time, the designed recycling method can also recover the acid reagent consumed in the leaching of battery materials, significantly reducing the consumption of acid in the process, realizing the recycling of leaching agent, and reducing the amount of waste discharged. The process flow is clean and green.

[0155] (2) By comparing Examples 1 and Examples 4-5, it can be seen that if the volume ratio of the leachate to the first extraction system is too low, nickel and cobalt cannot be completely recovered; if the volume ratio is too high, although efficient extraction of nickel and cobalt can be achieved, the utilization efficiency of the extractant will be greatly reduced, and the concentration of metal in the organic phase will also be reduced, which is not conducive to the back-extraction operation.

[0156] (3) By comparing Example 1 and Example 6-7, it can be seen that if the temperature is too low during the first organic back-extraction process in step S2, copper and zinc cannot be completely back-extracted, which is not conducive to the recovery of copper and zinc and the regeneration of the extractant; if the temperature is too high, metal ions such as nickel, cobalt, copper and zinc will be hydrolyzed during the back-extraction process, resulting in a decrease in metal recovery rate.

[0157] (4) By comparing Example 1 and Example 8, it can be seen that if hydrochloric acid with a concentration greater than 1 mol / L is used for back-extraction, the nitrogen heterocyclic extractant will form the corresponding hydrochloride salt in a high acid environment, thereby increasing its water solubility. This not only causes the loss of extractant, but also the organic matter dissolved in water will affect the purity of nickel-cobalt products.

[0158] (5) By comparing Example 1 and Example 9, it can be seen that if the concentration of chloride ions in the leachate is too low in step S1, the nickel-cobalt extraction rate and the nickel-cobalt recovery rate will decrease in step S2.

[0159] (6) By comparing Example 1 and Example 10, it can be seen that if the concentration of chloride ions in the first back-extraction solution is too high in step S2 of the present invention, it will lead to a large loss of nickel and cobalt during the purification process of the first back-extraction solution and a decrease in the total recovery rate of nickel and cobalt.

[0160] (7) By comparing Example 1 and Example 11-12, it can be seen that if the volume ratio of the first back-extraction liquid to the second extraction system in step S3 of the present invention is too low, the loss of nickel and cobalt will be large and the recovery rate will be low; if the volume ratio of the two is too high, the removal of copper and zinc will be incomplete, resulting in a decrease in the purity of the nickel and cobalt product.

[0161] (8) By comparing Example 1 and Comparative Example 1, it can be seen that if the addition of metal salt is omitted and only 3 mol / L hydrochloric acid is used as the leaching agent for leaching treatment, nickel and cobalt cannot be completely extracted, resulting in a decrease in nickel and cobalt recovery rate.

[0162] (9) By comparing Example 1 and Comparative Example 2, it can be seen that if the concentration of chloride ions in the leachate is controlled to 4 mol / L and step S3 is omitted, and the leachate is only extracted once using the first extraction system, the purity of the nickel-cobalt product will decrease.

[0163] In summary, the method for separating and recovering battery materials provided by this invention employs an extraction system to extract the leachate obtained from treatment with a specific component leaching agent. It combines back-extraction and purification processes to regulate the separation and recovery process, enhancing separation methods to efficiently separate nickel and cobalt from battery materials. This achieves efficient separation between impurity materials and high-value materials in battery materials. Simple purification recovers nickel and cobalt salts, which are then recovered through pyrolysis to obtain high-purity and high-recovery-rate nickel-cobalt oxides. Simultaneously, acid is also recovered and can be reused as a leaching agent, reducing acid consumption in the process, achieving leaching agent recycling, and reducing waste emissions. The process operation is clean and environmentally friendly. Furthermore, the separation and recovery method provided by this invention uses acid combined with metal salts as leaching agents, offering advantages such as high leaching efficiency and low acid consumption.

[0164] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A method for separating and recycling ternary battery materials, characterized in that, The method includes the following steps: (1) The ternary battery material is leached with a leaching agent to obtain a leachate; the leaching agent includes an acid and a metal salt; (2) The leachate is mixed with the first extraction system. After extraction and separation, a first organic phase loaded with nickel, cobalt, copper, zinc and iron and a first raffinate are obtained. The first organic phase is subjected to a first back-extraction. After separation, a first back-extraction solution containing nickel, cobalt, copper, zinc and iron is obtained. (3) The first back-extraction liquid is purified by a second extraction system of the same type as the first extraction system to obtain a second raffinate containing nickel and cobalt. The second raffinate is subjected to a first pyrolysis to recover oxides containing nickel and cobalt and a first acid reagent.

2. The method for separating and recycling ternary battery materials according to claim 1, characterized in that, The acid in the leaching agent in step (1) includes hydrochloric acid; Preferably, the metal salt in the leaching agent in step (1) includes a metal chloride; Preferably, the metal chloride includes any one or a combination of at least two of manganese chloride, calcium chloride, magnesium chloride, or aluminum chloride; Preferably, in the leaching agent described in step (1), the concentration of the acid is 1-6 mol / L; Preferably, in the leaching agent described in step (1), the concentration of the metal salt is 1-4 mol / L; Preferably, the total concentration of anions in the leaching agent in step (1) is 5 mol / L or higher; Preferably, the mass ratio of the ternary battery material to the volume of the leachate in step (1) is 1g:(1-20)L; Preferably, the metal elements leached from the leachate in step (1) include nickel, cobalt, copper, zinc, lithium, manganese, iron, magnesium, aluminum and calcium.

3. The method for separating and recycling ternary battery materials according to claim 1 or 2, characterized in that, Step (2) The first extraction system and step (3) The second extraction system are independently selected from nitrogen heterocyclic extractants; Preferably, the nitrogen heterocyclic extractant comprises a diluent and a nitrogen-containing heterocyclic amide compound; Preferably, the nitrogen-containing heterocyclic amide compound includes N-octylquinoline-8-carboxamide, N-isooctylquinoline-8-carboxamide, N,N-di(octyl)quinoline-8-carboxamide, N,N-di(isooctyl)quinoline-8-carboxamide, N-octylisoquinoline-8-carboxamide, N-isooctylisoquinoline-8-carboxamide, N,N-di(octyl)isoquinoline-8-carboxamide, N,N-di(isooctyl)isoquinoline-2-carboxamide, N-dodecylquinoline-8-carboxamide, N,N-bis(octyl)quinoline-8-carboxamide, etc. (Dodecyl)quinoline-8-carboxamide, N-dodecylisoquinoline-8-carboxamide, N,N-bis(dodecyl)isoquinoline-8-carboxamide, N-octyl-1H-pyrrole-2-carboxamide, N-isooctyl-1H-pyrrole-2-carboxamide, N,N-bis(octyl)-1H-pyrrole-2-carboxamide, N,N-bis(isooctyl)-1H-pyrrole-2-carboxamide, N-dodecyl-1H-pyrrole-2-carboxamide, N,N-bis(dodecyl)-1H-pyrrole-2-carboxamide N-C(Octyl)-1H-pyrrole-3-carboxamide, N-Isooctyl-1H-pyrrole-3-carboxamide, N,N-Di(Octyl)-1H-pyrrole-3-carboxamide, N,N-Di(Isooctyl)-1H-pyrrole-3-carboxamide, N-Dodecyl-1H-pyrrole-3-carboxamide, N,N-Bis(Dodecyl)-1H-pyrrole-3-carboxamide, N-Octylpyridine-3-carboxamide, N-Isooctylpyridine-3-carboxamide, N,N-Di(Octyl)pyridine-3-carboxamide The amide, N,N-di(isooctyl)pyridine-3-carboxamide, N-octylpyridine-4-carboxamide, N-isooctylpyridine-4-carboxamide, N,N-di(octyl)pyridine-4-carboxamide, N,N-di(isooctyl)pyridine-4-carboxamide, N-dodecylpyridine-3-carboxamide, N-dodecylpyridine-4-carboxamide, N,N-bis(dodecyl)pyridine-3-carboxamide or N,N-bis(dodecyl)pyridine-4-carboxamide, any one or a combination of at least two of these; Preferably, the diluent comprises any one or a combination of at least two of C7-C20 hydrocarbons, liquid ketones, or liquid alcohols; Preferably, in step (2), the volume percentage of nitrogen-containing heterocyclic amide compounds in the first extraction system is 5-50 vol%, preferably 10-40 vol%. Preferably, in step (3), the volume percentage of the nitrogen-containing heterocyclic amide compound in the second extraction system is 5-50 vol%, preferably 10-40 vol%.

4. The method for separating and recycling ternary battery materials according to any one of claims 1-3, characterized in that, The volume ratio of the leachate to the first extraction system in step (2) is 1:(1-10); Preferably, the stripping solvent used in step (2) for the first stripping includes water and / or acid, wherein the concentration of the acid is 0.1-1 mol / L; Preferably, the acid used in the first back-extraction step (2) includes hydrochloric acid; Preferably, in the first back-extraction process in step (2), the volume ratio of the first organic phase to the back-extraction solvent used in the first back-extraction is (1-30):1; Preferably, the temperature of the first back-extraction in step (2) is 10-70°C; Preferably, in step (2), the total concentration of anions in the first back-extraction solution is below 4 mol / L.

5. The method for separating and recycling ternary battery materials according to any one of claims 1-4, characterized in that, In the purification process described in step (3), the volume ratio of the first back-extraction solution to the second extraction system is (1-20):1; Preferably, the temperature of the first pyrolysis in step (3) is 600-800℃; Preferably, the time for the first pyrolysis in step (3) is 2-4 hours; Preferably, the type of the first acid reagent recovered in step (3) is the same as the type of acid in the leaching agent described in step (1); Preferably, after the second raffinate is subjected to a first pyrolysis, the first acid reagent recovered in step (3) is returned to step (1) for use in the leaching process.

6. The method for separating and recycling ternary battery materials according to any one of claims 1-4, characterized in that, After the purification process described in step (3), a second organic phase containing copper, zinc and iron is also obtained; Preferably, the method for separating and recovering ternary battery materials further includes step (4), specifically including performing a second back-extraction on the second organic phase containing copper, zinc and iron obtained after the purification treatment to obtain a second back-extraction solution containing copper, zinc and iron, and then performing a second pyrolysis to recover oxides and a second acid reagent containing copper, zinc and iron. Preferably, the stripping reagent used in step (4) the second stripping includes water and / or acid, wherein the concentration of the acid is 0.1-1 mol / L; Preferably, the acid used in the second back-extraction step (4) includes hydrochloric acid; Preferably, in the second back-extraction process in step (4), the volume ratio of the second organic phase to the back-extraction solvent used in the second back-extraction is (1-10):1; Preferably, the temperature of the second back-extraction in step (4) is above 50°C.

7. The method for separating and recycling ternary battery materials according to claim 6, characterized in that, In step (4), the temperature of the second pyrolysis is 600-800℃; Preferably, the second pyrolysis time in step (4) is 2-4 hours; Preferably, the type of the second acid reagent recovered in step (4) is the same as the type of acid in the leaching agent described in step (1); Preferably, after the second back-extraction solution is subjected to a second pyrolysis, the recovered second acid reagent is returned to step (1) for use in the leaching process.

8. The method for separating and recycling ternary battery materials according to claim 6 or 7, characterized in that, The metal ions in the first raffinate obtained in step (2) include lithium, manganese, magnesium, aluminum and calcium; Preferably, the method for separating and recovering ternary battery materials further includes step (5), the specific process of which includes: mixing the first raffinate with the third extraction system, and after extraction and separation, obtaining a third organic phase loaded with lithium and a third raffinate; Preferably, the third extraction system in step (5) includes a lithium composite extraction system; Preferably, in step (5), the volume ratio of the first raffinate to the third extraction system is (1-10):1; Preferably, the lithium-loaded third organic phase is subjected to a third back-extraction to obtain a lithium-containing solution; Preferably, the extraction solvent used in the third extraction includes water; Preferably, the volume ratio of the third organic phase to the stripping reagent used in the third stripping is (10-30):

1.

9. The method for separating and recycling ternary battery materials according to claim 8, characterized in that, The metal elements in the third raffinate obtained in step (5) include manganese, magnesium, aluminum and calcium; Preferably, the method for separating and recovering ternary battery materials further includes step (6), the specific process of which includes: performing split extraction on the third raffinate, obtaining a fourth organic phase loaded with manganese and a fourth raffinate after extraction and separation, performing a fourth back-extraction on the fourth organic phase, obtaining a manganese-containing solution after separation, and then performing a third pyrolysis on the manganese-containing solution to recover manganese oxides and a third acid reagent; Preferably, the metal elements in the fourth raffinate obtained in step (6) include manganese, iron, magnesium, aluminum and calcium; Preferably, in step (6), the molar ratio of manganese in the fourth organic phase to manganese in the fourth raffinate is 1:(0.1-15); Preferably, the extractant used in the split extraction in step (6) includes any one of tertiary amine extractants or quaternary ammonium salt extractants; Preferably, the volume ratio of the third raffinate in step (6) to the extractant used in the split extraction is 1:(1-10).

10. The method for separating and recycling ternary battery materials according to claim 9, characterized in that, In step (6), the extraction solvent used in the fourth back-extraction includes water; Preferably, in the fourth back-extraction process described in step (6), the volume ratio of the fourth organic phase to the back-extraction solvent is (1-10):

1. Preferably, the temperature of the third pyrolysis in step (6) is 600-800℃; Preferably, the third pyrolysis in step (6) takes 2-4 hours; Preferably, the type of the third acid solution recovered in step (6) is the same as the type of acid used in step (1); Preferably, the third acid solution recovered in step (6) is returned to step (1) for the leaching process; Preferably, the fourth raffinate recovered in step (6) is returned to step (1) for the leaching process.

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