A method for recovering copper-containing aluminum ternary battery waste

Abstract

The application provides a recovery method of copper-containing aluminum ternary battery waste, and the recovery method comprises the following steps: performing acid leaching treatment on the copper-containing aluminum ternary battery waste to obtain an acid leaching solution, performing copper extraction treatment on the acid leaching solution to obtain a copper-loaded organic phase and a copper-removed raffinate; mixing the copper-removed raffinate with a carbonate to perform aluminum removal treatment to obtain an aluminum-removed solution; performing resin fluorine removal treatment on the aluminum-removed solution to obtain a fluorine-removed solution; and performing step-by-step extraction treatment on the fluorine-removed solution to obtain a manganese-rich solution, a cobalt-rich solution and a nickel-rich solution. The application adopts the technologies of acid leaching, copper extraction, aluminum removal, fluorine removal and step-by-step extraction, can realize efficient and selective removal of copper and aluminum, and can further efficiently recover valuable metals in the ternary battery waste with high copper and aluminum contents, can improve the recovery rate of nickel, cobalt and manganese, can reduce the pollution of by-products, and can improve the process stability.

Description

Technical Field

[0001] This invention belongs to the field of resource recycling technology and relates to a method for recycling copper-aluminum ternary battery waste. Background Technology

[0002] With the rapid growth of the new energy vehicle and energy storage industries, the number of retired ternary (NCM) lithium-ion batteries continues to increase. Nickel, cobalt, and manganese in ternary batteries have high economic value, and the industrial process generally adopts a hydrometallurgical route: the material obtained after discharge dismantling / crushing and sorting (professionally known as black powder) is acid-leached to obtain a leachate containing Ni / Co / Mn / Li and various impurity ions, and then separated and commercialized through units such as impurity removal / extraction / crystallization.

[0003] However, in actual recycling scenarios, pretreatment sorting cannot always completely separate the current collector, especially when the material sources are complex (multiple models, multiple batches, different dismantling processes). Black powder often exhibits high copper and high aluminum characteristics: copper mainly comes from copper foil and connectors, while aluminum comes from aluminum foil and the shell. High copper (e.g., ≥5%) and high aluminum significantly amplify the separation difficulty of the wet system. Copper easily interferes with the subsequent Co / Ni / Mn extraction system and crystallization purity, and traditional copper removal often introduces secondary impurities and solid waste. Aluminum easily forms colloidal / hydrolytic precipitates in the acid leaching system, causing filtration difficulties and metal loss. At the same time, aluminum strongly complexes with some extractants, which may cause "third phase / emulsification / extractant loss".

[0004] In ternary battery wet processing systems where high copper and high aluminum coexist, traditional copper removal methods generate large amounts of solid waste and easily introduce secondary impurities, while direct extraction is prone to oil phase entrainment / impurity deposition, leading to operational instability. High aluminum content results in prominent issues such as colloidal precipitation, filtration difficulties, and co-loss of valuable metals. Furthermore, aluminum entering the acidic phosphorus-based extraction circuit causes extractant loss and reduced separation selectivity. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a method for recycling copper-aluminum ternary battery waste. The present invention employs technologies such as acid leaching, copper extraction, aluminum removal, fluorine removal, and stepwise extraction, which can achieve efficient and selective removal of copper and aluminum, thereby efficiently recovering valuable metals from ternary battery waste with high copper and aluminum content. Furthermore, it can improve the recovery rate of nickel, cobalt, and manganese, reduce by-product pollution, and improve process stability.

[0006] To achieve this objective, the present invention employs the following technical solution: This invention provides a method for recycling copper-aluminum ternary lithium battery waste, the recycling method comprising the following steps: Acid leaching was performed on copper-aluminum ternary battery waste to obtain acid leaching solution. Copper extraction was then performed on the acid leaching solution to obtain copper-supported organic phase and copper-removed raffinate. The copper-removing raffinate was mixed with carbonate for aluminum removal treatment to obtain an aluminum-removed solution. The defluorinated liquid after aluminum removal was subjected to resin defluorination treatment to obtain a defluorinated liquid. The defluorinated liquid was then subjected to segmented extraction treatment to obtain manganese-rich solution, cobalt-rich solution and nickel-rich solution, respectively.

[0007] Preferably, the copper content in the copper-aluminum ternary battery waste is 1% to 10%, and more preferably 5% to 10%.

[0008] Preferably, the mass percentage of aluminum in the copper-aluminum ternary battery waste is 1% to 6%, and more preferably 3% to 6%.

[0009] Preferably, the copper extractant used in the copper extraction process includes any one or a combination of at least two of oxime extractants, phosphate extractants, or phosphonic acid extractants.

[0010] Preferably, the copper extractant used in the copper extraction process includes LIX984 and / or LIX984N.

[0011] Preferably, the organic phase used in the copper extraction process further includes a diluent.

[0012] Preferably, the diluent comprises sulfonated kerosene and / or dearomatized solvent oil.

[0013] Preferably, the volume percentage of copper extractant in the organic phase used in the copper extraction process is 5% to 30%, more preferably 10% to 20%.

[0014] Preferably, the O / A ratio of the copper extraction treatment is (0.5~3):1.

[0015] Preferably, the temperature of the copper extraction treatment is 15℃~45℃.

[0016] Preferably, the copper extraction process has 1 to 5 extraction stages.

[0017] Preferably, the copper-supported organic phase is back-extracted to obtain a copper-containing back-extracting solution, which is then de-oiled and electrolyzed to produce copper as a byproduct.

[0018] Preferably, the stripping agent in the stripping treatment includes sulfuric acid.

[0019] Preferably, the anode used in the electrolytic copper production process includes a lead-based alloy anode and / or a titanium-based coated anode.

[0020] Preferably, the cathode used in the electrolytic copper production process includes any one or a combination of at least two of stainless steel cathodes, titanium cathodes, or copper starting plates.

[0021] Preferably, the current density of the electrolytic copper production process is 100 A / m. 2 ~400A / m 2 .

[0022] Preferably, the copper-removing raffinate is mixed with carbonates after being deoiled.

[0023] Preferably, the carbonate includes any one or a combination of at least two of sodium carbonate, potassium carbonate, ammonium carbonate, sodium bicarbonate, or ammonium bicarbonate, with sodium carbonate being the most preferred.

[0024] Preferably, the carbonate is added dropwise to the copper-removing raffinate in the form of a carbonate solution.

[0025] Preferably, the mass concentration of the carbonate solution is 5% to 30%.

[0026] Preferably, the endpoint pH of the aluminum removal treatment is 4.0 to 5.2.

[0027] Preferably, the temperature for the aluminum removal treatment is 30°C to 85°C.

[0028] Preferably, the reaction time for the aluminum removal treatment is 30 min to 180 min.

[0029] Preferably, the aluminum removal process is followed by aging.

[0030] Preferably, the aging time is 15 min to 120 min.

[0031] Preferably, the resin used for the defluorination treatment includes any one or a combination of at least two of the following: a strong base anion exchange resin, a weak base anion exchange resin, a selective defluorination resin, an aluminum-supported resin, a zirconium-supported resin, a lanthanum-supported resin, or a cerium-supported resin. More preferably, it is a combination of any one or a combination of at least two of the following: a zirconium-supported resin, an aluminum-supported resin, a lanthanum-supported resin, or a cerium-supported resin.

[0032] Preferably, the feed pH for the resin defluorination treatment is 3-6.

[0033] Preferably, the feed temperature for the resin defluorination treatment is 15℃~50℃.

[0034] Preferably, the contact time of the resin bed in the resin defluorination treatment is 6 min to 60 min, and more preferably 12 min to 30 min.

[0035] Preferably, the F in the defluorinated liquid - The mass concentration is ≤10mg / L.

[0036] Preferably, the segmented extraction process includes sequential extraction of manganese, cobalt, and nickel, followed by back-extraction to obtain manganese-rich, cobalt-rich, and nickel-rich solutions, respectively.

[0037] The numerical range described in this invention includes not only the point values ​​listed above, but also any point values ​​within the numerical ranges not listed above. Due to space limitations and for the sake of brevity, this invention will not exhaustively list all the specific point values ​​included in the range.

[0038] Compared with the prior art, the present invention has the following beneficial effects: (1) This invention employs technologies such as acid leaching, copper extraction, aluminum removal, fluorine removal, and stepwise extraction, which can achieve This technology enables the efficient recycling of copper-aluminum ternary battery waste and the preparation of high-purity metal products, while also improving the recovery rate, reducing by-product pollution, and enhancing process stability.

[0039] (2) The recycling method described in this invention can achieve efficient and selective removal of copper under high copper conditions, and ensure the recovery rate of target metals such as nickel, cobalt and manganese; under high aluminum system, aluminum impurities are removed in a controllable and selective manner, while reducing the loss of valuable metals. Therefore, the recycling method described in this invention can also achieve excellent recycling effect on copper-aluminum ternary battery waste with high copper (5%~10%) and high aluminum (3%~6%) content.

[0040] (3) The present invention first extracts copper and then precipitates aluminum with carbonate, and the aluminum removal rate can reach more than 99%. The loss of nickel, cobalt and manganese coprecipitation is less than 2%, which avoids the complexation poisoning of aluminum on the subsequent extractant, extends the service life of the organic phase and reduces the process operating cost. The added resin defluorination step can reduce the fluoride ion concentration to below 10mg / L, avoid fluoride impurities affecting the purity of subsequent products, and greatly improve the process stability. Copper can be directly electrolyzed to obtain qualified cathode copper, realizing the resource recovery of copper without additional solid waste discharge.

[0041] (4) The method for recycling copper-aluminum ternary battery waste described in this invention can obtain a manganese-rich solution with a purity of over 98.8% and a manganese recovery rate of over 98.1%, a cobalt-rich solution with a purity of over 99.4% and a cobalt recovery rate of over 99.5%, and a nickel-rich solution with a purity of over 99.2% and a nickel recovery rate of over 99.1%. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the process flow for the recycling method of copper-aluminum ternary battery waste according to an embodiment of the present invention. Detailed Implementation

[0043] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0044] The scope of this invention can be defined by lower and upper limits. The selected lower and upper limits define the boundaries of a specific range. The range defined in this way can be defined by the inclusion or exclusion of endpoints. Any endpoint can be independently selected for inclusion or exclusion, and all lower and upper limits can be arbitrarily combined to form new ranges. That is, any lower limit can be combined with any upper limit to form an effective range. For example, if the ranges of 60~120 and 80~110 are listed for specific parameters, it should be understood that the ranges of 60~110 and 80~120 also fall within the scope of this invention. In addition, if the minimum range values ​​1 and 2 are listed, and the maximum range values ​​3, 4 and 5 are also listed, then all ranges of 1~3, 1~4, 1~5, 2~3, 2~4 and 2~5 fall within the scope of this invention. In this invention, the numerical range "a~b" represents a shortened representation of any combination of real numbers between a and b, where a and b are both real numbers. For example, the numerical range "0~5" means that all real numbers between 0 and 5 have been fully listed in this document, and "0~5" is only a shortened representation of this set of numerical combinations. When a parameter is expressed as an integer ≥2, it is equivalent to listing positive integers that meet the requirements, such as 2, 3, 4, 5, 6, 7, 8, 9, 10, etc. When a parameter is expressed as an integer selected from "2~10", it is equivalent to listing any integer among 2, 3, 4, 5, 6, 7, 8, 9, and 10.

[0045] In this invention, "a combination of at least two" refers to a quantity greater than or equal to 2 unless otherwise specified. For example, "any one or a combination of at least two" means that any one of the listed items can be selected, or a combination of at least two of the listed items formed in a manner that does not conflict and enables the implementation of this invention. In this invention, unless otherwise specified, the features or solutions corresponding to "and / or" cover any one of two or more related listed items, as well as any and all combinations of the related listed items. The arbitrary and all combinations include any two related listed items, any more related listed items, or a combination of all related listed items. For example, "A and / or B" means a set consisting of A, B, and combinations of A and B, where "containing A and / or B" can be understood, depending on the context of the statement, as containing A, containing B, or simultaneously containing both A and B. In this invention, "optional" means that the corresponding feature, component, step or solution is not necessary, that is, it is selected from either "with" or "without". If there are multiple "optional" limitations in a technical solution, unless otherwise specified and there is no technical conflict or mutual constraint, each "optional" limitation is independent and does not affect the others.

[0046] In this invention, technical features or solutions described using open-ended terms such as "comprising" or "including" do not exclude additional non-conflicting elements beyond the listed elements unless otherwise specified. They are considered to disclose both closed-ended features or solutions consisting solely of the listed elements and open-ended features or solutions that may include additional non-conflicting elements beyond the listed elements. For example, if A includes a1, a2, and a3, unless otherwise specified, this means that A can consist only of a1, a2, and a3, or it can include other non-conflicting elements based on a1, a2, and a3. This corresponds to the disclosure of technical solutions such as "A consists of a1, a2, and a3," "A is selected from a1, a2, and a3," and "A not only includes a1, a2, and a3, but may also include other non-conflicting elements." All embodiments and optional embodiments of this invention, unless otherwise specified and without technical conflict, can be combined to form new technical solutions, and such combinations fall within the scope of this invention. The term "embodiment" as used in this invention means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment or implementation of the invention. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. Those skilled in the art can understand, explicitly and implicitly, that the embodiments described in this invention can be combined with other embodiments that do not conflict with the technology.

[0047] In this invention, the order in which the steps are written in the methods described in each embodiment does not imply a strict execution order. The actual execution order of each step should be determined according to its function and possible internal logic. Unless otherwise specified, all steps of this invention can be executed in the order in which they are written or in any order that does not conflict with the technology.

[0048] This invention provides a method for recycling copper-aluminum ternary lithium battery waste in some specific embodiments, the recycling method comprising the following steps: Acid leaching was performed on copper-aluminum ternary battery waste to obtain acid leaching solution. Copper extraction was then performed on the acid leaching solution to obtain copper-supported organic phase and copper-removed raffinate. The copper-removing raffinate was mixed with carbonate for aluminum removal treatment to obtain an aluminum-removed solution. The defluorinated liquid after aluminum removal was subjected to resin defluorination treatment to obtain a defluorinated liquid. The defluorinated liquid was then subjected to segmented extraction treatment to obtain manganese-rich solution, cobalt-rich solution and nickel-rich solution, respectively.

[0049] This invention first extracts valuable metals from copper-aluminum ternary battery waste into an acid leaching solution. Since copper is a major impurity affecting subsequent metal separation, interfering with the extraction of cobalt, nickel, and manganese, and even causing organic phase entrainment and oil phase contamination, thus reducing metal recovery rate and product purity, this application prioritizes copper extraction to remove copper from the solution, obtaining a copper-free leaching solution. In this solution, aluminum is mainly present as Al. 3+ Aluminum exists in its hydrolyzed / complexed forms. If it directly enters the subsequent Mn / Co / Ni stepwise extraction system, aluminum will preferentially or competitively extract in the acidic phosphorus-based extractant, occupying the effective capacity of the extractant and increasing extractant consumption. Furthermore, the complexes formed between aluminum and the extractant are highly stable, difficult to back-extract, and easily accumulate in the organic phase, leading to increased viscosity, slower phase separation, and an increased risk of third phase or emulsification. This affects the separation selectivity and continuous operation stability of Mn, Co, and Ni. This invention removes aluminum impurities through carbonate precipitation, ensuring that aluminum does not enter the organic phase during subsequent extraction, thus avoiding interference with the extractant and significantly improving the efficiency of metal separation. After aluminum removal, fluoride ions in the liquid will react with Al in the system. 3+ Fe 3+ High-valence metal ions form fluoride complexes, altering the aqueous phase morphology and extraction partitioning behavior of these ions, leading to fluctuations in the pH control window, separation coefficient, and back-extraction behavior of subsequent extraction systems. This invention incorporates a resin defluorination step before the stepwise extraction of manganese, cobalt, and nickel. In traditional wet recovery processes, fluoride ions readily form complexes with impurity ions such as aluminum and iron, and may migrate into the organic phase or back-extraction solution along with the acidic phosphorus-based extraction system, resulting in extractant loss, deteriorated phase separation, increased impurities in the back-extraction solution, and the risk of excessive fluoride impurities in sulfate products. The newly added resin defluorination process of this invention effectively reduces the fluoride ion concentration before multi-stage extraction, minimizing the adverse effects of fluoride on extractant performance, phase behavior, and product purity, thereby improving the stability of subsequent manganese, cobalt, and nickel separation processes. Finally, by employing stepwise extraction technology, manganese, cobalt, and nickel are extracted independently, effectively improving the recovery rate and purity of cobalt, nickel, and manganese.

[0050] In the recycling method described in this invention, if aluminum is removed before copper, copper ions will co-precipitate with aluminum during the carbonate aluminum precipitation step. This not only prevents copper from being recycled, but also increases the amount of aluminum slag. The residual copper will enter the subsequent segmented extraction system, which will reduce the purity of the nickel-cobalt-manganese product.

[0051] In some embodiments, the mass percentage of copper in the copper-aluminum ternary battery waste is 1% to 10%, for example: 1%, 2%, 5%, 8% or 10%, etc., not limited to the listed values, other unlisted values ​​within this range are also applicable, preferably 5% to 10%.

[0052] In some embodiments, the mass percentage of aluminum in the copper-aluminum ternary battery waste is 1% to 6%, for example: 1%, 2%, 4%, 5% or 6%, etc., not limited to the listed values, other unlisted values ​​within this range are also applicable, preferably 3% to 6%.

[0053] In some embodiments, the copper extractant used in the copper extraction process includes any one or a combination of at least two of oxime extractants, phosphate extractants, or phosphonic acid extractants. Typical but non-limiting combinations include combinations of oxime extractants and phosphonic acid extractants, combinations of oxime extractants and phosphate extractants, or combinations of phosphate extractants and phosphonic acid extractants, etc.

[0054] In some embodiments, the copper extractant used in the copper extraction process includes LIX984 and / or LIX984N.

[0055] The specific type of copper extractant described in this invention is not the only way to implement this invention. However, by limiting the type, concentration, pH, phase ratio, and number of stages of the extractant, the selective removal effect of copper in high copper systems can be improved, the co-extraction loss of Ni, Co, and Mn can be reduced, and the risk of copper impurity accumulation in subsequent extraction systems can be reduced.

[0056] In some embodiments, the organic phase used in the copper extraction process further includes a diluent.

[0057] In some embodiments, the diluent includes sulfonated kerosene and / or dearomatic solvent oil.

[0058] In some embodiments, the volume percentage of copper extractant in the organic phase used for copper extraction is 5% to 30%, for example: 5%, 8%, 10%, 20% or 30%, etc., not limited to the listed values, and other unlisted values ​​within this range are also applicable, preferably 10% to 20%.

[0059] In some embodiments, the O / A ratio of the copper extraction treatment is (0.5~3):1, for example: 0.5:1, 1:1, 1.5:1, 2:1 or 3:1, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0060] In some embodiments, the temperature of the copper extraction treatment is 15°C to 45°C, for example: 15°C, 20°C, 30°C, 40°C or 45°C, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0061] In some embodiments, the copper extraction process has 1 to 5 extraction stages, for example: 1 stage, 2 stages, 3 stages, 4 stages or 5 stages.

[0062] In some embodiments, the copper-supported organic phase is back-extracted to obtain a copper-containing back-extracting solution, which is then de-oiled and electrolyzed to produce copper as a byproduct.

[0063] This invention involves back-extracting a copper-supported organic phase to obtain a copper back-extracting solution. After degreasing, the oil content of the back-extracting solution is ensured to be <10 mg / L to prevent the formation of a hydrophobic oil film or organic contamination layer on the cathode surface. This reduces the risk of cathode needle-like crystallization, nodulation, pitting, blackening, embrittlement, and localized short circuits. Simultaneously, it reduces the impact of organic matter on the electrode surface, current distribution, and electrolyte circulation stability, improving current efficiency and the quality of the cathode copper by-product. Electrolysis yields metallic copper as a by-product, effectively utilizing copper resources and avoiding secondary copper pollution.

[0064] In some embodiments, the back-extraction agent for the back-extraction process includes sulfuric acid.

[0065] In some embodiments, the anode used in the electrolytic copper production process includes lead-based alloy anodes and / or titanium-based coated anodes.

[0066] In some embodiments, the cathode used in the electrolytic copper production process includes any one or a combination of at least two of stainless steel cathodes, titanium cathodes, or copper starting plates. Typical but non-limiting combinations include combinations of titanium cathodes and copper starting plates, combinations of stainless steel cathodes and copper starting plates, or combinations of stainless steel cathodes and titanium cathodes.

[0067] In some embodiments, the current density of the electrolytic copper production process is 100 A / m. 2 ~400A / m 2 For example: 100A / m 2 150A / m 2 200A / m 2 300A / m 2 or 400A / m 2 The term "etc." is not limited to the listed values; it also applies to other unlisted values ​​within the range.

[0068] In some embodiments, the copper-removing raffinate is mixed with carbonates after being deoiled.

[0069] In some embodiments, the carbonate includes any one or a combination of at least two of sodium carbonate, potassium carbonate, ammonium carbonate, sodium bicarbonate, or ammonium bicarbonate. Typical but non-limiting combinations include combinations of sodium carbonate and potassium carbonate, combinations of potassium carbonate and ammonium carbonate, or combinations of sodium carbonate and sodium bicarbonate, etc., preferably sodium carbonate.

[0070] In some embodiments, the carbonate is added dropwise to the copper-removing raffinate in the form of a carbonate solution.

[0071] In some embodiments, the mass concentration of the carbonate solution is 5% to 30%, for example: 5%, 8%, 10%, 20% or 30%, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0072] In some embodiments, the endpoint pH of the aluminum removal treatment is 4.0 to 5.2, for example: 4.0, 4.2, 4.5, 5 or 5.2, etc., not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0073] In some embodiments, the temperature of the aluminum removal process is 30°C to 85°C, for example: 30°C, 40°C, 50°C, 60°C or 85°C, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0074] In some embodiments, the reaction time for the aluminum removal treatment is 30 min to 180 min, for example: 30 min, 50 min, 100 min, 150 min or 180 min, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0075] In some embodiments, the aluminum removal process is followed by aging.

[0076] In some embodiments, the aging time is 15 min to 120 min, for example: 15 min, 30 min, 50 min, 100 min or 120 min, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0077] In some embodiments, the resin used for the defluorination treatment includes any one or a combination of at least two of the following: a strongly basic anion exchange resin, a weakly basic anion exchange resin, a selective defluorination resin, an aluminum-supported resin, a zirconium-supported resin, a lanthanum-supported resin, or a cerium-supported resin. Typical but non-limiting combinations include a combination of a weakly basic anion exchange resin and a selective defluorination resin, a combination of a selective defluorination resin and an aluminum-supported resin, or a combination of an aluminum-supported resin and a cerium-supported selective defluorination resin. Preferably, it is a combination of any one or at least two of the following: a zirconium-supported resin, an aluminum-supported resin, a lanthanum-supported resin, or a cerium-supported resin.

[0078] In some embodiments, the feed pH for the resin defluorination treatment is 3 to 6, for example: 3, 3.5, 4, 5 or 6, etc., not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0079] In some embodiments, the feed temperature for the resin defluorination treatment is 15°C to 50°C, for example: 15°C, 20°C, 30°C, 40°C or 50°C, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0080] In some embodiments, the contact time of the resin bed in the resin defluorination treatment is 6 min to 60 min, for example: 6 min, 10 min, 20 min, 40 min or 60 min, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable, preferably 12 min to 30 min.

[0081] In some embodiments, the F in the defluorinated solution - The mass concentration is ≤10mg / L.

[0082] In some embodiments, the segmented extraction process includes sequential extraction of manganese, cobalt, and nickel, followed by back-extraction to obtain manganese-rich, cobalt-rich, and nickel-rich solutions, respectively.

[0083] The segmented extraction process described in this invention specifically includes: sending the defluorinated liquid into a first extraction system, extracting manganese ions using a suitable extractant, back-extracting to obtain a manganese-rich solution, sending the raffinate after the first extraction into a second extraction system, extracting cobalt ions using a suitable extractant, back-extracting to obtain a cobalt-rich solution, crystallizing to prepare cobalt sulfate, and sending the raffinate after the second extraction into a third extraction system, extracting nickel ions using a suitable extractant, back-extracting to obtain a nickel-rich solution, crystallizing to prepare nickel sulfate.

[0084] Operating conditions of the extraction system: The operating conditions (such as temperature, pH value, extractant concentration, contact time, etc.) in the first, second and third extraction systems can be adjusted according to different process requirements, and the extractant concentration in each step can be set to different ranges to adapt to different batches of recovered materials.

[0085] The manganese extractant has a volume fraction of 5%–30% in the organic phase and a saponification rate of 20%–70%. During manganese extraction, the pH of the aqueous phase is controlled at 2.0–4.0; the temperature is 20℃–50℃; the O / A ratio is 0.5:1–3:1; and the number of extraction stages is 2–8. The manganese-loaded organic phase is back-extracted using sulfuric acid, with a back-extraction acid concentration of 0.5 mol / L–3.0 mol / L.

[0086] The cobalt extractant has a volume fraction of 5%–35% in the organic phase; the saponification rate is 20%–75%. During cobalt extraction, the pH of the aqueous phase is controlled at 4.5–6.2; the temperature is 20℃–55℃; the O / A ratio is 0.5:1–3:1; and the number of extraction stages is 3–10. The cobalt-loaded organic phase is back-extracted with sulfuric acid at a concentration of 0.5 mol / L–3.0 mol / L.

[0087] The nickel extractant has a volume fraction of 10%–40% in the organic phase; the saponification rate is 30%–80%. During nickel extraction, the pH of the aqueous phase is controlled at 5.0–7.0; the temperature is 20℃–60℃; the O / A ratio is 0.5:1–4:1; and the number of extraction stages is 3–10. The nickel-loaded organic phase is back-extracted using sulfuric acid, with a back-extraction acid concentration of 0.5 mol / L–3.5 mol / L.

[0088] The obtained manganese-rich, cobalt-rich, and nickel-rich solutions were degreased, finely filtered, and then evaporated, concentrated, and cooled to crystallize, respectively, to prepare manganese sulfate, cobalt sulfate, and nickel sulfate products. The concentrations of the corresponding metal ions in the pre-crystallization back-extraction solutions (i.e., the manganese-rich, cobalt-rich, and nickel-rich solutions) were controlled at 60 g / L to 160 g / L; the pH of the crystallization mother liquor was controlled at 2.0 to 5.5; the evaporation and concentration temperature was 50℃ to 95℃; the final cooling temperature was 15℃ to 40℃; and the cooling rate was 0.05℃ / min to 1.0℃ / min.

[0089] In the embodiments and comparative examples of this invention, the copper-aluminum ternary battery waste used contains nickel at a mass ratio of 30.79%, cobalt at a mass ratio of 3.65%, manganese at a mass ratio of 1.47%, lithium at a mass ratio of 4.25%, copper at a mass ratio of 7.87%, and aluminum at a mass ratio of 4.29%.

[0090] In the embodiments and comparative examples of this invention, after obtaining a copper-supported organic phase, a 180 g / L sulfuric acid solution was used for back-extraction to obtain a copper-containing back-extraction solution. The back-extraction conditions were O / A = 3:1. Before electrolysis, the copper back-extraction solution underwent sequential treatments including static phase separation, coalescence degreasing, activated carbon adsorption, and precision filtration to reduce the content of entrained organic matter to ≤5 mg / L, preferably ≤2 mg / L; and the suspended solids content to ≤10 mg / L. The electrolysis conditions were as follows: the anode was a lead-calcium-tin alloy anode, the cathode was a stainless steel cathode, the electrolysis temperature was 48℃, and the current density was 250 A / m. 2 The voltage is 2.2V, and after electrolysis, metallic copper is obtained as a byproduct. The copper electrolysis recovery rate is ≥98.0%, and the purity of the cathode copper is ≥99.95%.

[0091] The oil removal treatment described in the embodiments and comparative examples of the present invention adopts a combination of "gravity sedimentation + coalescence oil removal + precision filtration" to control the content of organic matter entrained in the aqueous phase to ≤10mg / L.

[0092] The fractional extraction conditions used in the embodiments and comparative examples of this invention are as follows: The defluorinated liquid was subjected to a first extraction treatment using a P204 extraction system (P204 and sulfonated kerosene in a volume ratio of 2:8) (pH 2.8, O / A 1:1, extraction stage 4), yielding a manganese-rich organic phase and a first raffinate. The manganese-rich organic phase was then back-extracted, and a manganese-rich solution was obtained using a 1.5 mol / L sulfuric acid solution. The first raffinate was then subjected to a second extraction treatment using a P507 extraction system (P507 and sulfonated kerosene in a volume ratio of 2:8) (pH 5.2, O / A 1:1, extraction stage 5), yielding a cobalt-rich organic phase and a second raffinate. The cobalt-rich organic phase was then back-extracted, and a cobalt-rich solution was obtained using a 2 mol / L sulfuric acid solution. The second raffinate was subjected to a third extraction treatment using a BC196 extraction system (BC196 and sulfonated kerosene in a volume ratio of 2.5:7.5) (pH 6, O / A 1.5:1, extraction stage 5) to obtain a nickel-rich organic phase and a third raffinate. The nickel-rich organic phase was then back-extracted, and a nickel-rich solution was obtained using a 2.2 mol / L sulfuric acid solution.

[0093] Example 1 This embodiment provides a method for recycling copper-aluminum ternary lithium battery waste. A schematic diagram of the process flow of the recycling method is shown below. Figure 1 As shown, the recycling method includes the following steps: Two-stage acid leaching was performed on copper-aluminum ternary battery waste. In the first stage, 98% sulfuric acid and 27.5% hydrogen peroxide were added at a volume ratio of 1:1.5. In the second stage, 98% sulfuric acid and 27.5% hydrogen peroxide were added at a volume ratio of 1:1. The total acid leaching reaction time was 4 hours, the reaction temperature was 80℃, and the solid-liquid ratio was 1:5. After acid leaching, the insoluble residue was removed by filtration, and the acid leaching solution was obtained. The organic phase was extracted using LIX984N (LIX984N extractant accounted for 20% by volume, and the remainder was sulfonated kerosene) at 30℃ for copper extraction treatment. The O / A ratio was 2:1, and the extraction stage was 3 stages, resulting in a copper-loaded organic phase and copper-free raffinate. After degreasing the copper raffinate, a 15% sodium carbonate solution was added dropwise to the copper raffinate at 60°C to remove aluminum. The pH endpoint was 4.6. After reacting for 90 min, the solution was aged for 30 min and then filtered through a plate and frame diaphragm to obtain the aluminum-removed solution. Using D201 macroporous strong-base styrene-based type I anion exchange resin, the feed pH was controlled at 4.5, the temperature at 30℃, the space velocity at 3 BV / h, and the resin bed contact time at 20 min. The resulting solution was subjected to resin defluorination treatment to obtain F... - The defluorinated solution with a mass concentration of 10 mg / L was subjected to fractional extraction to obtain manganese-rich solution, cobalt-rich solution and nickel-rich solution respectively.

[0094] Example 2 This embodiment provides a method for recycling copper-aluminum ternary lithium battery waste. A schematic diagram of the process flow of the recycling method is shown below. Figure 1 As shown, the recycling method includes the following steps: Two-stage acid leaching was performed on copper-aluminum ternary battery waste. In the first stage, 98% sulfuric acid and 27.5% hydrogen peroxide were added at a volume ratio of 1:1.5. In the second stage, 98% sulfuric acid and 27.5% hydrogen peroxide were added at a volume ratio of 1:1. The total acid leaching reaction time was 4 hours, the reaction temperature was 80℃, and the solid-liquid ratio was 1:5. After acid leaching, the insoluble residue was removed by filtration, and the acid leaching solution was obtained. The organic phase was extracted using LIX984 (LIX984 extractant accounted for 10% by volume, and the remainder was sulfonated kerosene) at 45℃ to perform copper extraction treatment on the acid leaching solution. The O / A ratio was 3:1, and the number of extraction stages was 5, resulting in a copper-loaded organic phase and copper-free raffinate. After degreasing the copper raffinate, a 5% sodium carbonate solution was added dropwise to the copper raffinate at 85°C to remove aluminum. The pH endpoint was 5.2. After reacting for 180 min, the solution was aged for 120 min and then filtered through a plate and frame diaphragm to obtain the aluminum-removed solution. Using D201 macroporous strong-base styrene-based type I anion exchange resin, the feed pH was controlled at 6, the temperature at 15℃, the space velocity at 3 BV / h, and the resin bed contact time at 20 min. The resulting solution was subjected to resin defluorination treatment to obtain F. - The defluorinated solution with a mass concentration of 10 mg / L was subjected to fractional extraction to obtain manganese-rich solution, cobalt-rich solution and nickel-rich solution respectively.

[0095] Example 3 This embodiment provides a method for recycling copper-aluminum ternary lithium battery waste. A schematic diagram of the process flow of the recycling method is shown below. Figure 1 As shown, the recycling method includes the following steps: Two-stage acid leaching was performed on copper-aluminum ternary battery waste. In the first stage, 98% sulfuric acid and 27.5% hydrogen peroxide were added at a volume ratio of 1:1.5. In the second stage, 98% sulfuric acid and 27.5% hydrogen peroxide were added at a volume ratio of 1:1. The total acid leaching reaction time was 4 hours, the reaction temperature was 80℃, and the solid-liquid ratio was 1:5. After acid leaching, the insoluble residue was removed by filtration, and the acid leaching solution was obtained. The organic phase was extracted using LIX984 (LIX984 extractant volume ratio was 15%, the remainder was sulfonated kerosene) at 15℃ to perform copper extraction treatment on the acid leaching solution. The O / A ratio was 0.5:1, and the number of extraction stages was 3, resulting in a copper-loaded organic phase and copper-free raffinate. After degreasing the copper raffinate, a 30% sodium carbonate solution was added dropwise to the copper raffinate at 30°C to remove aluminum. The pH endpoint was 4. After reacting for 30 minutes, the solution was aged for 15 minutes and then filtered through a plate and frame diaphragm to obtain the aluminum-removed solution. Using D201 macroporous strong-base styrene-based type I anion exchange resin, the feed pH was controlled at 3, the temperature at 50℃, the space velocity at 3 BV / h, and the resin bed contact time at 20 min. The resulting solution was subjected to resin defluorination treatment to obtain F. - The defluorinated solution with a mass concentration of 10 mg / L was subjected to fractional extraction to obtain manganese-rich solution, cobalt-rich solution and nickel-rich solution respectively.

[0096] Example 4 The only difference between this embodiment and Example 1 is that the volume percentage of LIX984 extractant in the organic phase extracted by LIX984N is 5%, while the other conditions and parameters are exactly the same as in Example 1.

[0097] Example 5 The only difference between this embodiment and Example 1 is that the volume percentage of LIX984 extractant in the organic phase extracted by LIX984N is 30%, while the other conditions and parameters are exactly the same as in Example 1.

[0098] Example 6 The only difference between this embodiment and Embodiment 1 is that, except that the mass concentration of the sodium carbonate solution used for aluminum treatment is 2%, all other conditions and parameters are exactly the same as in Embodiment 1.

[0099] Example 7 The only difference between this embodiment and Embodiment 1 is that, except that the mass concentration of the sodium carbonate solution used for aluminum treatment is 40%, the other conditions and parameters are exactly the same as in Embodiment 1.

[0100] Example 8 The only difference between this embodiment and Example 1 is that the final pH of the aluminum treatment is 3.5, while the other conditions and parameters are exactly the same as in Example 1.

[0101] Example 9 The only difference between this embodiment and Example 1 is that, except that the final pH of the aluminum treatment is 5.5, the other conditions and parameters are exactly the same as in Example 1.

[0102] Example 10 The only difference between this embodiment and Embodiment 1 is that sulfuric acid is used to adjust the pH of the dealuminated solution to 3.0, followed by selective defluorination using zirconium-supported NDA-F type nano-resin (zirconia-supported resin). Under conditions of 30°C and a feed space velocity of 3 BV / h, the dealuminated solution is passed through the selective defluorination resin bed for resin defluorination treatment. The empty bed contact time of the resin bed is 20 min, yielding F... - The defluorinated solution with a mass concentration of 3 mg / L was prepared under the same conditions and parameters as in Example 1.

[0103] Comparative Example 1 The only difference between this comparative example and Example 1 is that iron powder is used to reduce copper ions in the acid leaching solution to remove copper; all other conditions and parameters are exactly the same as in Example 1.

[0104] Comparative Example 2 The only difference between this comparative example and Example 1 is that the pH of the copper removal solution was adjusted to 5.5, and aluminum was removed by hydrolysis to obtain the aluminum-removed solution. All other conditions and parameters are exactly the same as in Example 1.

[0105] Comparative Example 3 The only difference between this comparative example and Example 1 is that iron powder is used to reduce copper ions in the acid leaching solution to obtain a copper-removed solution. The pH of the copper-removed solution is adjusted to 5.5 for hydrolysis to remove aluminum, resulting in an aluminum-removed solution. All other conditions and parameters are exactly the same as in Example 1.

[0106] Performance testing: The purity of the manganese-rich, cobalt-rich, and nickel-rich solutions obtained in the examples and comparative examples was analyzed using ICP-OES (inductively coupled plasma optical emission spectrometry). The recoveries of nickel, cobalt, and manganese were calculated using the following formula: The test results are shown in Table 1: Table 1 As shown in Table 1, from Examples 1 to 10, the method for recycling copper-aluminum ternary battery waste described in this invention can achieve a manganese-rich solution with a purity of over 96.8% and a manganese recovery rate of over 95.8%, a cobalt-rich solution with a purity of over 97.5% and a cobalt recovery rate of over 96.9%, a nickel-rich solution with a purity of over 97.3% and a nickel recovery rate of over 96.7%. By adjusting the recycling conditions, the manganese-rich solution can achieve a purity of over 98.8% and a manganese recovery rate of over 98.1%, the cobalt-rich solution with a purity of over 99.4% and a cobalt recovery rate of over 99.5%, and the nickel-rich solution with a purity of over 99.2% and a nickel recovery rate of over 99.1%.

[0107] A comparison of Examples 1 and 4-5 shows that in the copper-aluminum ternary battery waste recycling method of the present invention, the volume percentage of copper extractant in the organic phase used for copper extraction affects the recycling effect. Controlling the volume percentage of copper extractant in the organic phase used for copper extraction at 10%-20% results in a better recycling effect. If the volume percentage of copper extractant in the organic phase used for copper extraction is too high, the viscosity of the organic phase increases, the phase separation rate decreases, and the risk of entrainment, emulsification, or a third phase is easily generated. At the same time, it may increase the co-extraction or entrainment loss of metals such as Ni, Co, and Mn. If the volume percentage of copper extractant in the organic phase used for copper extraction is too low, the copper loading capacity of the organic phase is insufficient, and copper removal is incomplete under the same stage and phase conditions. Residual copper enters the subsequent segmented extraction system, affecting the purity of manganese, cobalt, and nickel products.

[0108] Comparing Examples 1 and 6-7, it can be seen that in the method for recycling copper-aluminum ternary battery waste described in this invention, the mass concentration of the sodium carbonate solution used in the aluminum removal treatment affects the recycling effect. Controlling the mass concentration of the sodium carbonate solution used in the aluminum removal treatment at 5%~30% results in a better recycling effect. If the mass concentration of the sodium carbonate solution used in the aluminum removal treatment is too high, it is easy to cause local co-precipitation of Ni, Co, and Mn or adsorption and encapsulation by aluminum precipitate. At the same time, the precipitate particles are easy to agglomerate, resulting in a decrease in filtration performance. If the mass concentration of the sodium carbonate solution used in the aluminum removal treatment is too low, the dosage volume is too large, the system is significantly diluted, the pH control fluctuation at the reaction endpoint increases, the solid-liquid separation load increases, and the aluminum removal effect and subsequent extraction stability decrease.

[0109] Comparing Examples 1 and 8-9, it can be seen that in the recycling method of copper-aluminum ternary battery waste described in this invention, the final pH of the aluminum removal treatment affects the recycling effect. Controlling the final pH of the aluminum removal treatment at 4-5.2 results in a better recycling effect. If the final pH of the aluminum removal treatment is too high, Ni, Co, and Mn are prone to hydrolysis, carbonate precipitation, or adsorption and entrainment by aluminum precipitation, leading to increased loss of valuable metals. If the final pH of the aluminum removal treatment is too low, aluminum hydrolysis and precipitation are insufficient. After the residual aluminum enters the subsequent acidic phosphorus extraction system, it will occupy the extractant capacity, increase the viscosity of the organic phase, prolong the phase separation time, and increase the risk of emulsification or third phase.

[0110] A comparison of Examples 1 and 10 shows that the resins used in the defluorination treatment of copper-aluminum ternary battery waste in the present invention are diverse. Among them, the cost of using strong basic anion exchange resin is low and the fixed bed operation is simple, but the defluorination selectivity and anti-interference effect are slightly worse than those of zirconium-loaded resin, aluminum-loaded resin, lanthanum-loaded resin or cerium-loaded resin.

[0111] A comparison of Example 1 and Comparative Examples 1-3 shows that, due to the high Cu content in the raw materials, the iron powder copper removal system is difficult to adapt to high copper loads. The iron powder reduction method is suitable for materials with a Cu content below 1.5%, but not for high-copper black powder with a Cu content exceeding 2%. In high-copper systems, iron powder reduction can only remove a portion of the copper, and a large amount of Cu still enters the subsequent extraction system. If more iron powder is added to improve the copper removal rate, the amount of copper-containing iron slag will increase significantly, and Fe will be introduced. 2+ / Fe 3+ Impurities increase the burden on subsequent iron removal and solid waste treatment. In high-alumina systems, conventional hydrolysis not only fails to completely remove Al but also results in significant Ni loss. The actual Al content is approximately 4.3%, about 4.3 times the design baseline. Excessive aluminum leads to high viscosity of Al(OH)3 colloid, which adsorbs Ni / Co. Simultaneously, the higher pH induces Ni / Co hydroxide precipitation, thus amplifying the loss of the target metal.

[0112] 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 recycling copper-aluminum ternary lithium battery waste, characterized in that, The recycling method includes the following steps: Acid leaching was performed on copper-aluminum ternary battery waste to obtain acid leaching solution. Copper extraction was then performed on the acid leaching solution to obtain copper-supported organic phase and copper-removed raffinate. The copper-removing raffinate was mixed with carbonate for aluminum removal treatment to obtain an aluminum-removed solution. The defluorinated liquid after aluminum removal was subjected to resin defluorination treatment to obtain a defluorinated liquid. The defluorinated liquid was then subjected to segmented extraction treatment to obtain manganese-rich solution, cobalt-rich solution and nickel-rich solution, respectively.

2. The recycling method as described in claim 1, characterized in that, The copper content in the copper-aluminum ternary battery waste is 1% to 10% by mass, preferably 5% to 10%; And / or, the mass percentage of aluminum in the copper-aluminum ternary battery waste is 1% to 6%, preferably 3% to 6%.

3. The recycling method as described in claim 1 or 2, characterized in that, The copper extraction agent used in the copper extraction process includes any one or a combination of at least two of oxime extractants, phosphate extractants, or phosphonic acid extractants. And / or, the copper extractant used in the copper extraction treatment includes LIX984 and / or LIX984N; And / or, the organic phase used in the copper extraction process also includes a diluent; And / or, the diluent includes sulfonated kerosene and / or dearomatized solvent oil; And / or, the volume percentage of copper extractant in the organic phase used in the copper extraction treatment is 5% to 30%, preferably 10% to 20%.

4. The recycling method according to any one of claims 1-3, characterized in that, The O / A ratio for the copper extraction treatment is (0.5~3):1; And / or, the temperature of the copper extraction treatment is 15℃~45℃; And / or, the copper extraction process has 1 to 5 extraction stages.

5. The recycling method according to any one of claims 1-4, characterized in that, The copper-supported organic phase is back-extracted to obtain a copper-containing back-extracting solution. After the copper-containing back-extracting solution is de-oiled, it is electrolyzed to produce copper to obtain metallic copper byproduct. And / or, the stripping agent for the stripping treatment includes sulfuric acid; And / or, the anode used in the electrolytic copper production process includes lead-based alloy anodes and / or titanium-based coated anodes; And / or, the cathode used in the electrolytic copper production process includes any one or a combination of at least two of stainless steel cathodes, titanium cathodes, or copper starter sheets; And / or, the current density of the electrolytic copper production process is 100 A / m 2 ~400A / m 2 .

6. The recycling method according to any one of claims 1-5, characterized in that, The copper-removing raffinate is mixed with carbonates after being deoiled. And / or, the carbonate includes any one or a combination of at least two of sodium carbonate, potassium carbonate, ammonium carbonate, sodium bicarbonate, or ammonium bicarbonate, preferably sodium carbonate; And / or, the carbonate is added dropwise to the copper-free raffinate in the form of a carbonate solution; And / or, the mass concentration of the carbonate solution is 5% to 30%.

7. The recycling method according to any one of claims 1-6, characterized in that, The endpoint pH of the aluminum removal treatment is 4.0~5.2; And / or, the temperature of the aluminum removal treatment is 30℃~85℃; And / or, the reaction time for the aluminum removal treatment is 30 min to 180 min; And / or, the aluminum removal process is followed by aging; And / or, the aging time is 15 min to 120 min.

8. The recycling method according to any one of claims 1-7, characterized in that, The resin used in the defluorination treatment includes any one or a combination of at least two of the following: strong basic anion exchange resin, weak basic anion exchange resin, selective defluorination resin, aluminum-supported resin, zirconium-supported resin, lanthanum-supported resin, or cerium-supported resin. Preferably, it is a combination of any one or at least two of the following: zirconium-supported resin, aluminum-supported resin, lanthanum-supported resin, or cerium-supported resin.

9. The recycling method according to any one of claims 1-8, characterized in that, The pH of the feed for the resin defluorination treatment is 3-6; And / or, the feed temperature for the resin defluorination treatment is 15℃~50℃; And / or, the contact time of the resin bed in the resin defluorination treatment is 6 min to 60 min, preferably 12 min to 30 min; And / or, the F in the defluorinated solution - The mass concentration is ≤10mg / L.

10. The recycling method according to any one of claims 1-9, characterized in that, The segmented extraction process includes sequential extraction of manganese, cobalt, and nickel, followed by back-extraction to obtain manganese-rich, cobalt-rich, and nickel-rich solutions, respectively.

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