A method for recovering valuable elements by aging and leaching battery powder

Abstract

This invention provides a method for recovering valuable elements from battery powder through leaching. The method includes: mixing sulfur powder, concentrated sulfuric acid, and battery powder, and carrying out a aging reaction to obtain an aged material; leaching the aged material to obtain a leachate; mixing the leachate with the pretreated material for a first conditioning treatment, followed by solid-liquid separation to obtain a first liquid phase; subjecting the first liquid phase to impurity removal and solid-liquid separation, and then performing stepwise extraction and back-extraction on the resulting second liquid phase to recover valuable elements such as nickel, cobalt, manganese, lithium, and zinc. This invention can shorten the overall extraction process, reduce the consumption of auxiliary materials such as acids and liquid alkalis at the downstream end, and lower production costs.

Description

Technical Field

[0001] This invention relates to the field of hydrometallurgical technology, and in particular to a method for recovering valuable elements by leaching and curing battery powder. Background Technology

[0002] The main valuable metals in ternary lithium batteries are nickel, cobalt, manganese, and lithium, among which nickel, cobalt, and manganese are high-valence compounds with high content. Battery powder is a powder containing nickel, cobalt, manganese, lithium, and carbon powder obtained after battery dismantling, crushing, and screening. The mass percentage of nickel, cobalt, and manganese is 30-35%, and the mass percentage of lithium is 3-4%, which has high recycling value. Currently, the main processing technologies for battery powder are wet leaching and pyrometallurgical combined wet leaching processes. The wet process involves dismantling, crushing, screening, leaching, and extraction to obtain a battery-grade nickel, cobalt, and manganese sulfate solution. This process uses reduction leaching, resulting in a high recovery rate of nickel, cobalt, and manganese. However, in the extraction section, the traditional extraction process has a long flow and consumes a large amount of auxiliary materials.

[0003] CN113174486A discloses a method for recycling valuable metals from waste lithium-ion batteries. This method involves first adding concentrated sulfuric acid to the battery powder for aging and leaching, followed by water leaching. After solid-liquid separation, the first graphite slag is added to dilute sulfuric acid for acid leaching, then a reducing agent is added for reduction leaching, followed by alkali precipitation of impurities. Finally, solid-liquid separation yields a second graphite slag and a second liquid valuable metal. This method utilizes the carbonization effect of concentrated sulfuric acid to decompose organic matter in the battery powder, solving problems such as organic matter coating the active material of the battery powder and bubbling and overflowing caused by organic matter during water and acid leaching. This method reduces the roasting step, removes organic matter from the battery powder through the aging process, simplifies the recycling process of valuable metals from waste lithium batteries, and reduces production costs, but the leaching process is not shortened.

[0004] CN112375910A discloses a method for recycling and processing waste power battery powder. The method involves mixing and roasting battery materials using a reducing agent to obtain reduced battery powder. The roasted battery powder is then leached with pure water to obtain a lithium hydroxide solution and nickel-cobalt-manganese slag. The lithium hydroxide solution is then carbonized by passing carbon dioxide through it to obtain lithium carbonate. The nickel-cobalt-manganese slag is leached with sulfuric acid, and the leaching mixture is separated by extraction to obtain a nickel sulfate solution. This method uses reduction roasting followed by leaching to improve the lithium extraction rate. However, the reduction of nickel, cobalt, and manganese to metals and the subsequent sulfuric acid leaching generate hydrogen gas, causing foaming and posing a high safety risk.

[0005] CN118147461A discloses a method for treating the leachate of ternary lithium-ion battery cathode black powder. This method involves oxidative neutralization and hydrolysis to remove iron and aluminum, followed by two-stage extraction and copper replacement. The process is short, yielding a high-purity nickel-cobalt-manganese-containing solution, thus enhancing the resource value of waste battery cathode materials. Furthermore, the use of manganese soap followed by P204 and BC196 extractants results in a high separation coefficient and large processing capacity. The back-extraction acid used has low acidity, low acid consumption, and low auxiliary material consumption. However, in actual production, slag is generated in the back-extraction stage when BC196 is used for full extraction, affecting product quality.

[0006] Therefore, there is a need to develop new methods for recovering nickel, cobalt, manganese, and lithium from the cathode of ternary lithium-ion batteries. Summary of the Invention

[0007] To address the aforementioned technical problems, this invention provides a method for recovering valuable elements through leaching of battery powder. This invention can shorten the process flow, reduce the roasting step, and lower energy consumption. After aging, only pure water is needed for leaching at room temperature, increasing the concentration of valuable elements in the first liquid phase, reducing the amount of pure water used, wastewater generation, and steam usage, thus lowering production costs. Moreover, it can achieve full recovery and utilization of valuable elements such as nickel, cobalt, manganese, zinc, and lithium, resulting in high resource utilization.

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

[0009] This invention provides a method for recovering valuable elements by leaching and curing battery powder, the method comprising:

[0010] (1) Mix sulfur powder, concentrated sulfuric acid and battery powder, and carry out a aging reaction to obtain aging material; the aging material is then leached to obtain leachate.

[0011] (2) The leachate in step (1) undergoes a first conditioning treatment and solid-liquid separation to obtain a first liquid phase; the first liquid phase is then purified and separated to obtain a second liquid phase.

[0012] (3) The second liquid phase is subjected to a first extraction to obtain a first raffinate, and the extract obtained from the first extraction is subjected to a first back-extraction to obtain a first back-extraction solution containing nickel, copper and zinc.

[0013] (4) The first back-extraction solution containing nickel, copper and zinc is subjected to copper removal and zinc removal by a second extraction in sequence. The second raffinate obtained is a nickel sulfate solution. The second extract obtained by the second extraction to remove zinc is subjected to a second back-extraction to obtain a zinc sulfate solution.

[0014] (5) The first raffinate is subjected to a third extraction to obtain a third raffinate solution containing sodium lithium. The third extract obtained from the third extraction is subjected to a third back-extraction to obtain a cobalt manganese sulfate solution.

[0015] There is no specific order between steps (4) and (5).

[0016] The method for recovering valuable elements from battery powder through aging and leaching provided by this invention enables comprehensive utilization of battery powder, shortens the leaching process, reduces auxiliary material consumption, and enhances the industrial production capacity of the process. Firstly, an aging process is employed to carbonize the organic matter in the battery powder, which will not affect subsequent leaching. Furthermore, water leaching is used, eliminating the need for heating and reducing energy consumption. Secondly, water can be used directly for leaching, and the washing water can be used as a leaching solvent, achieving wastewater recycling and eliminating wastewater production. This increases the amount of washing water used and reduces the metal loss rate in the carbon slag.

[0017] Preferably, the battery powder in step (1) is a ternary lithium-ion battery cathode powder.

[0018] Preferably, the total mass percentage of nickel, cobalt, and manganese in the battery powder is 30wt% to 35wt%, for example, it can be 30wt%, 30.6wt%, 31.2wt%, 31.7wt%, 32.3wt%, 32.8wt%, 33.4wt%, 33.9wt%, 34.5wt%, or 35wt%, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0019] Preferably, the sulfur powder is industrial sulfur powder with a purity greater than 99 wt%.

[0020] Preferably, the concentrated sulfuric acid has a mass fraction of ≥93wt%, such as 93wt%, 93.7wt%, 94.4wt%, 95wt%, 95.7wt%, 96.4wt%, 97wt%, 97.7wt%, 98.4wt%, or 99wt%, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0021] Preferably, the temperature of the ripening reaction in step (1) is 90 to 140°C, for example, it can be 90°C, 96°C, 102°C, 107°C, 113°C, 118°C, 124°C, 129°C, 135°C or 140°C, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0022] Preferably, the ripening reaction time is 5 to 20 hours, for example, 5 hours, 7 hours, 9 hours, 10 hours, 12 hours, 14 hours, 15 hours, 17 hours, 19 hours or 20 hours, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0023] Preferably, the mass ratio of battery powder to sulfur powder is 15 to 32:1, for example, it can be 15:1, 17:1, 19:1, 21:1, 23:1, 25:1, 27:1, 29:1, 31:1 or 32:1, etc.

[0024] Preferably, the mass ratio of concentrated sulfuric acid to battery powder is 0.9 to 1.4:1, for example, it can be 0.9:1, 0.96:1, 1.02:1, 1.07:1, 1.13:1, 1.18:1, 1.24:1, 1.29:1, 1.35:1 or 1.4:1, etc.

[0025] Preferably, the solvent used for leaching in step (1) is water.

[0026] Preferably, the leaching time is 1 to 3 hours, for example, it can be 1 hour, 1.3 hours, 1.5 hours, 1.7 hours, 1.9 hours, 2.2 hours, 2.4 hours, 2.6 hours, 2.8 hours or 3 hours, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0027] Preferably, the leaching temperature is 10 to 30°C, for example, it can be 10°C, 13°C, 15°C, 17°C, 19°C, 22°C, 24°C, 26°C, 28°C or 30°C, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0028] Preferably, the metal element composition of the leachate includes: Ni: 40-60 g / L, Co: 20-30 g / L, Mn: 15-25 g / L, and Li: 10-16 g / L.

[0029] Ni: 40–60 g / L, for example, 40 g / L, 43 g / L, 45 g / L, 47 g / L, 49 g / L, 52 g / L, 54 g / L, 56 g / L, 58 g / L, or 60 g / L, etc., but not limited to the listed values. Other unlisted values ​​within this range also apply. Co: 20–30 g / L, for example, 20 g / L, 22 g / L, 23 g / L, 24 g / L, 25 g / L, 26 g / L, 27 g / L, 28 g / L, 29 g / L, or 30 g / L, etc., but not limited to the listed values. Other values ​​within this range also apply. The values ​​not listed also apply. Mn: 15-25 g / L, for example, 15 g / L, 17 g / L, 18 g / L, 19 g / L, 20 g / L, 21 g / L, 22 g / L, 23 g / L, 24 g / L or 25 g / L, etc., but not limited to the listed values. Other unlisted values ​​within this range also apply. Li: 10-16 g / L, for example, 10 g / L, 11 g / L, 12 g / L, 13 g / L, 14 g / L, 15 g / L or 16 g / L, etc., but not limited to the listed values. Other unlisted values ​​within this range also apply.

[0030] Preferably, the liquid-to-solid ratio of the leaching is 2 to 5 ml:1g, for example, it can be 2 ml:1g, 2.4 ml:1g, 2.7 ml:1g, 3 ml:1g, 3.4 ml:1g, 3.7 ml:1g, 4 ml:1g, 4.4 ml:1g, 4.7 ml:1g, or 5 ml:1g, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0031] Preferably, carbon residue is separated during the leaching process.

[0032] Preferably, the first conditioning process in step (2) includes: mixing the leachate and the calcined battery powder to neutralize the residual acid.

[0033] The first conditioning process of this invention involves adding roasted battery powder to the leachate to neutralize excess residual acid and oxidize ferrous iron. After pressure filtration, the residue is mixed with the aging process section for use.

[0034] Preferably, the calcined battery powder is obtained by calcining pretreatment of battery powder.

[0035] Preferably, the temperature of the calcination pretreatment is 400-500℃, for example, it can be 400℃, 412℃, 423℃, 434℃, 445℃, 456℃, 467℃, 478℃, 489℃ or 500℃, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0036] Preferably, the calcination pretreatment time is 1 to 6 hours, for example, it can be 1 hour, 1.6 hours, 2.2 hours, 2.7 hours, 3.3 hours, 3.8 hours, 4.4 hours, 4.9 hours, 5.5 hours or 6 hours, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0037] Preferably, the amount of calcined battery powder added in the first conditioning process is 1.1 to 1.2 times the theoretical amount required to convert the residual acid into salt. For example, it can be 1.1 times, 1.12 times, 1.13 times, 1.14 times, 1.15 times, 1.16 times, 1.17 times, 1.18 times, 1.19 times, or 1.2 times, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0038] The battery powder produced by this invention contains oxides of nickel, cobalt, copper and zinc after calcination, which can react with residual acid to form nickel salts, cobalt salts, copper salts or zinc salts.

[0039] Preferably, the duration of the first adjustment process is 1 to 2 hours, for example, it can be 1 hour, 1.2 hours, 1.3 hours, 1.4 hours, 1.5 hours, 1.6 hours, 1.7 hours, 1.8 hours, 1.9 hours or 2 hours, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0040] Preferably, the solid-liquid separation after the first conditioning treatment in step (2) is pressure filtration.

[0041] Preferably, the impurity removal in step (2) includes mixing an oxidant, an alkali, and a first liquid phase to remove iron and aluminum.

[0042] In this invention, hydrogen peroxide and manganese carbonate are added to the leachate to adjust the pH and remove impurities such as iron and aluminum. After pressure filtration, the iron and aluminum slag is slurried and washed with low acid, which can remove iron and aluminum at room temperature, reduce energy consumption, and use the slurry washing water as pure water for leaching of the slag, reducing the introduction of water into the system, increasing the metal transfer concentration, increasing the amount of washing water used, and reducing the metal loss rate in the slag.

[0043] Preferably, the oxidant includes hydrogen peroxide.

[0044] Preferably, the alkali comprises manganese carbonate.

[0045] Preferably, the pH value in the impurity removal process is 5 to 6.5, for example, it can be 5, 5.2, 5.4, 5.5, 5.7, 5.9, 6, 6.2, 6.4 or 6.5, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0046] Preferably, the solid phase obtained after the solid-liquid separation is subjected to pulping and washing.

[0047] Preferably, the endpoint pH of the pulping wash is 2 to 4, for example, it can be 2, 2.3, 2.5, 2.7, 2.9, 3.2, 3.4, 3.6, 3.8 or 4, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0048] Preferably, in step (3), the first extraction system in the first extraction includes tung oil-based carboxylic acid, a co-extractant, and an organic solvent.

[0049] Preferably, the co-extractant comprises any one or a combination of at least two of pyridinium ester, β-diketone, diisobutyl ketone, 4,5-dimethylimidazole, or 1,2-dialkylimidazole, wherein typical but non-limiting combinations are combinations of pyridinium ester and β-diketone, diisobutyl ketone and β-diketone, pyridinium ester and diisobutyl ketone, 4,5-dimethylimidazole and β-diketone, and 4,5-dimethylimidazole and 1,2-dialkylimidazole.

[0050] Preferably, the organic solvent in the first extraction system is sulfonated kerosene.

[0051] Preferably, the mass percentage of tung oil-based carboxylic acid in the first extraction system is 20wt% to 25wt%, for example, it can be 20wt%, 20.6wt%, 21.2wt%, 21.7wt%, 22.3wt%, 22.8wt%, 23.4wt%, 23.9wt%, 24.5wt%, or 25wt%, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0052] It is worth noting that the first extraction system needs to be saponified before the second liquid phase is extracted.

[0053] Preferably, the saponification rate of the first extraction system is 40% to 50%, for example, it can be 40%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49% or 50%, etc., but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0054] Preferably, the mass percentage of the co-extractant in the first extraction system is 5wt% to 10wt%, for example, it can be 5wt%, 5.6wt%, 6.2wt%, 6.7wt%, 7.3wt%, 7.8wt%, 8.4wt%, 8.9wt%, 9.5wt%, or 10wt%, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0055] The present invention further preferably includes a co-extractant mass percentage in the first extraction system within the above-mentioned range, which can reduce impurities entrained in the first back-extraction solution containing nickel, copper, and zinc with a smaller amount of extractant used.

[0056] Preferably, the volume ratio of the first extraction system to the second liquid phase is 3 to 6:1, for example, it can be 3:1, 3.2:1, 3.5:1, 4:1, 4.3:1, 4.5:1, 4.7:1, 4.9:1, 5.2:1, 5.4:1, 5.6:1, 5.8:1 or 6:1, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0057] Preferably, the first back-extraction is performed using a sulfuric acid solution.

[0058] Preferably, the concentration of the sulfuric acid solution in the first back-extraction is 2 to 5 mol / L, for example, it can be 2 mol / L, 2.3 mol / L, 2.5 mol / L, 3.0 mol / L, 3.5 mol / L, 4 mol / L, 4.2 mol / L, 4.3 mol / L, 4.4 mol / L, 4.5 mol / L, 4.6 mol / L, 4.7 mol / L, 4.8 mol / L, 4.9 mol / L or 5 mol / L, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0059] Preferably, a first washing step is included between the first extraction and the first back-extraction.

[0060] Preferably, the washing acid in the first washing includes a sulfuric acid solution.

[0061] Preferably, the volume ratio of the first extraction system to the washing acid in the first washing process is 20 to 60:1, for example, it can be 20:1, 22:1, 25:1, 30:1, 34:1, 37:1, 40:1, 44:1, 47:1, 50:1, 54:1, 57:1 or 60:1, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0062] Preferably, the concentration of the washing acid in the first washing is 0.5 to 0.8 mol / L, for example, it can be 0.5 mol / L, 0.52 mol / L, 0.53 mol / L, 0.6 mol / L, 0.63 mol / L, 0.65 mol / L, 0.67 mol / L, 0.69 mol / L, 0.72 mol / L, 0.74 mol / L, 0.76 mol / L, 0.78 mol / L or 0.8 mol / L, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0063] Preferably, the first back-extraction is followed by a first anti-iron reaction and a first clarification.

[0064] Anti-iron extraction refers to the process of back-extracting iron ions from the extraction system to better restore its original performance. During extraction, the presence of both oil and aqueous phases can easily lead to emulsification. Therefore, clarification after anti-iron extraction effectively prevents emulsification, restoring the extraction performance of the system. Anti-iron extraction and clarification are steps following back-extraction in this invention and are common techniques in the field. There are no special restrictions on the specific feed solution, composition, or ratio to the extraction system; adjustments can be made according to actual conditions.

[0065] For example, the first extraction stage has 6-8 stages, the first washing stage has 4-6 stages, the first back-extraction stage has 4-7 stages, the first anti-ironing stage has 2-3 stages, the first clarification stage has 2-3 stages, and the saponification stage is one stage. Saponification is performed using liquid alkali (25wt%–35wt%), with the saponification rate controlled at 40%–50%. In the first extraction system, the mass percentage of tung oil-based carboxylic acid compound is 20wt%–25wt%, the mass percentage of co-extractant is 5wt%–10wt%, and the remainder is sulfonated kerosene. The volume ratio of the extraction system and the second liquid phase in the first extraction is (3–6):1. During the first washing process, the volume ratio of the first extraction system to the washing acid is 20–60:1, the washing acid concentration is 0.5–0.8 mol / L, and the acid concentration during the first back-extraction is 2–5 mol / L. The acid used in both the first washing and the first back-extraction is sulfuric acid.

[0066] Preferably, the copper removal in step (4) includes resin copper removal.

[0067] Preferably, the copper removal process includes: removing copper from the first back-extraction solution with copper-removing resin to obtain a copper-removed solution, and then using a desiccant to desorb the copper-removed resin to obtain a copper-containing desiccant solution.

[0068] Preferably, the acid used for analysis is sulfuric acid.

[0069] Preferably, the concentration of the desorbing acid is 1 to 2 mol / L, for example, it can be 1 mol / L, 1.2 mol / L, 1.3 mol / L, 1.4 mol / L, 1.5 mol / L, 1.6 mol / L, 1.7 mol / L, 1.8 mol / L, 1.9 mol / L or 2 mol / L, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0070] Preferably, the copper-containing solution is subjected to manganese powder replacement to remove copper, thereby preparing sponge copper.

[0071] The present invention preferably uses manganese powder for copper removal by displacement to obtain sponge copper. At the same time, the copper removal waste liquid is introduced into the second liquid phase to recover valuable metals, and the purity of sponge copper reaches more than 98%.

[0072] Preferably, the amount of manganese powder added in the copper removal process is 0.9 to 1 times the molar content of copper in the copper-containing solution. For example, it can be 0.9 times, 0.92 times, 0.93 times, 0.94 times, 0.95 times, 0.96 times, 0.97 times, 0.98 times, 0.99 times, or 1 times, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0073] Preferably, the manganese powder replacement copper removal includes: mixing manganese powder and copper-containing analytical solution to remove copper, thereby obtaining sponge copper and copper removal waste liquid.

[0074] Preferably, the copper-removed liquid in step (4) is subjected to a second extraction in a second extraction system to remove zinc.

[0075] Preferably, the second extraction system comprises an organophosphate compound and a solvent oil.

[0076] Preferably, the organophosphate compound in the second extraction system includes any one or a combination of at least two of P204, P507 or C272, wherein typical but non-limiting combinations are the combination of P204 and P507, the combination of C272 and P507, the combination of P204 and C272, and preferably P507.

[0077] Using P507 for zinc removal can effectively reduce the nickel carried over during zinc extraction with P204 compared to P204, thus reducing the amount of acid used for washing.

[0078] Preferably, the mass percentage of organophosphate extractant in the second extraction system is 2wt% to 10wt%, for example, it can be 2wt%, 2.9wt%, 3.8wt%, 4.7wt%, 5.6wt%, 6.5wt%, 7.4wt%, 8.3wt%, 9.2wt%, or 10wt%, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0079] Preferably, the second extraction system does not undergo saponification.

[0080] Preferably, the second extraction stage is 6 to 8 stages, for example, it can be 6, 7 or 8 stages.

[0081] Preferably, the solvent oil is sulfonated kerosene.

[0082] Preferably, the volume ratio of the second extraction system to the copper-removed liquid is 0.8 to 1.2:1, for example, it can be 0.8:1, 0.85:1, 0.89:1, 0.94:1, 0.98:1, 1.03:1, 1.07:1, 1.12:1, 1.16:1 or 1.2:1, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0083] Preferably, the second back-extraction is performed using a sulfuric acid solution.

[0084] Preferably, the concentration of the sulfuric acid solution in the second back-extraction is 3 to 5 mol / L, for example, it can be 3 mol / L, 3.3 mol / L, 3.5 mol / L, 3.7 mol / L, 3.9 mol / L, 4.2 mol / L, 4.4 mol / L, 4.6 mol / L, 4.8 mol / L or 5 mol / L, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0085] Preferably, a second washing is further included between the second extraction and the second back-extraction.

[0086] Preferably, the washing acid in the second washing comprises a sulfuric acid solution.

[0087] Preferably, the volume ratio of the second extraction system to the washing acid in the second washing process is 20 to 60:1, for example, it can be 20:1, 25:1, 29:1, 34:1, 38:1, 43:1, 47:1, 52:1, 56:1 or 60:1, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0088] Preferably, the concentration of the washing acid in the second washing is 0.3 to 0.5 mol / L, for example, it can be 0.3 mol / L, 0.33 mol / L, 0.35 mol / L, 0.37 mol / L, 0.39 mol / L, 0.42 mol / L, 0.44 mol / L, 0.46 mol / L, 0.48 mol / L or 0.5 mol / L, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0089] Specifically, the second extraction process employs saponification-free zinc extraction, with 6-8 extraction stages, 4-6 washing stages, 3-7 back-extraction stages, and 2-3 clarification stages. The volume ratio of the second extraction system to the copper-removed solution is 0.8–1.2:1. The concentration of the washing acid in the second washing is 0.3–0.5 mol / L. In the second washing, the volume ratio of the second extraction system to the washing acid solution is 20–60:1. The acid concentration in the second back-extraction is 3–5 mol / L. Both the acid in the second washing and the second back-extraction is sulfuric acid. After zinc removal, the second raffinate is obtained, and the back-extraction solution obtained from the second back-extraction is a high-purity zinc sulfate solution.

[0090] Furthermore, in this invention, the high-purity zinc sulfate solution is prepared by electrolysis to produce electrolytic zinc products, which are then melted to obtain zinc ingots.

[0091] Preferably, the third extraction system in step (5) includes organophosphate compounds and solvent oil.

[0092] The specific process is as follows: the third extraction system is used to extract cobalt, manganese and calcium and magnesium from the first raffinate, the pH of the raffinate is controlled at 6-7, cobalt, manganese, calcium and magnesium are extracted, and the calcium and magnesium are washed in the washing section, and the washing water is treated separately.

[0093] Preferably, the organophosphate compounds in the third extraction system include any one or a combination of at least two of P507, C272, P204, P227 or TBP, wherein typical but non-limiting combinations are the combination of P507 and C272, the combination of P204 and C272, the combination of P507 and P204, the combination of TBP and C272, and the combination of TBP and P227.

[0094] Preferably, the mass percentage of organophosphate extractant in the third extraction system is 20wt% to 25wt%, for example, it can be 20wt%, 20.6wt%, 21.2wt%, 21.7wt%, 22.3wt%, 22.8wt%, 23.4wt%, 23.9wt%, 24.5wt%, or 25wt%, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0095] Preferably, the saponification rate of the third extraction system is 40% to 45%, for example, it can be 40%, 40.6%, 41.2%, 41.7%, 42.3%, 42.8%, 43.4%, 43.9%, 44.5% or 45%, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0096] Preferably, the third extraction stage has 6 to 8 stages, for example, it can be 6, 7 or 8 stages.

[0097] Preferably, the solvent oil in the third extraction system is sulfonated kerosene.

[0098] Preferably, the volume ratio of the third extraction system to the first raffinate is 4 to 6:1, for example, it can be 4:1, 4.3:1, 4.5:1, 4.7:1, 4.9:1, 5.2:1, 5.4:1, 5.6:1, 5.8:1 or 6:1, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0099] Preferably, the third back-extraction is performed using a sulfuric acid solution.

[0100] Preferably, the concentration of the sulfuric acid solution in the third back-extraction is 2 to 3 mol / L, for example, it can be 2 mol / L, 2.2 mol / L, 2.3 mol / L, 2.4 mol / L, 2.5 mol / L, 2.6 mol / L, 2.7 mol / L, 2.8 mol / L, 2.9 mol / L or 3 mol / L, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0101] Preferably, a third washing is further included between the third extraction and the third back-extraction.

[0102] Preferably, the washing acid in the third wash includes a hydrochloric acid solution.

[0103] Preferably, the volume ratio of the third extraction system to the washing acid in the third washing is 40 to 60:1, for example, it can be 40:1, 43:1, 45:1, 47:1, 49:1, 52:1, 54:1, 56:1, 58:1 or 60:1, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0104] Preferably, the concentration of the washing acid in the third wash is 0.3 to 0.6 mol / L, for example, it can be 0.3 mol / L, 0.34 mol / L, 0.37 mol / L, 0.4 mol / L, 0.44 mol / L, 0.47 mol / L, 0.5 mol / L, 0.54 mol / L, 0.57 mol / L or 0.6 mol / L, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0105] Preferably, the lithium-containing sodium solution is used to prepare lithium carbonate via MVR evaporation and carbonization process.

[0106] In this invention, MVR evaporation (Mechanical Vapor Recompression) refers to mechanical vapor recompression evaporation, also known as multi-effect evaporation.

[0107] Preferably, the third washing produces a cobalt-manganese-calcium-magnesium chloride solution.

[0108] Preferably, the cobalt-containing manganese calcium magnesium chloride solution is subjected to cobalt removal treatment with a cobalt removal resin and the cobalt removal resin is then analyzed to obtain a cobalt sulfate solution.

[0109] The cobalt-containing manganese calcium magnesium chloride solution of the present invention removes cobalt by adsorption with cobalt removal resin, and the resulting cobalt sulfate eluent is returned to the third extraction.

[0110] Preferably, the cobalt removal process also produces a calcium-magnesium-containing solution.

[0111] Preferably, the calcium-magnesium solution is adjusted to a pH of 13 or higher by adding an alkaline solution to precipitate calcium and magnesium. The resulting mixed system is then separated into solid and liquid phases to obtain calcium-magnesium hydroxide slag and a magnesium-removed liquid. A pH of 13 or higher can be, for example, 13.0, 13.1, 13.2, 13.3, 13.5, 13.8, or 14.0.

[0112] Preferably, the magnesium-removed liquid is used as an alkali for saponification.

[0113] Preferably, a third clarification is further included between the third washing and the third back-extraction.

[0114] Preferably, the process further includes a third antiferrolysis and a fourth clarification performed sequentially after the third back-extraction.

[0115] Specifically, the overall process of the third extraction is as follows: third extraction stages 6-8, third washing stages 6-8, third clarification stage 1, third back-extraction stages 4-6, third anti-ironing stages 2-3, and fourth clarification stages 2-3. The third extraction system uses liquid alkali (25wt%–35wt%) for saponification, with the saponification rate controlled at 40%–45%. During the third extraction, the volume ratio of the third extraction system to the first raffinate is 4–6:1. The washing acid in the third washing is hydrochloric acid with a concentration of 0.3–0.6 mol / L. During the third washing, the volume ratio of the third extraction system to the washing acid is 40–60:1. The back-extraction acid in the third back-extraction is sulfuric acid with a concentration of 2–3 mol / L. This yields a cobalt-manganese sulfate solution (third back-extraction solution), a calcium-magnesium chloride solution (third washing solution), and a lithium-containing sodium solution (raffinate obtained from the third extraction). The lithium-containing sodium solution is then used to prepare lithium carbonate through MVR evaporation and carbonation processes.

[0116] Compared with the prior art, the present invention has at least the following beneficial effects:

[0117] (1) The method for recovering valuable elements by leaching battery powder using sulfur powder is described in this invention. The method involves a reduction and aging reaction of the battery powder, which allows for the complete leaching of nickel, cobalt, manganese, and lithium. Compared with existing technologies, this method shortens the process flow, reduces the roasting step, and lowers energy consumption. Furthermore, after the aging reaction, only pure water is needed for leaching at room temperature, which increases the concentration of valuable metal elements in the second liquid phase, reduces the amount of pure water used, the generation of wastewater, and the use of steam, thereby reducing production costs.

[0118] (2) In the method for recovering valuable elements by leaching battery powder maturation provided by the present invention, the washing water of carbon slag, the washing water of iron and aluminum slag and the condensate from MVR evaporation are used as pure water and transferred to the water leaching section, which can ensure a high metal concentration, greatly reduce the output of wastewater, and achieve a wastewater recovery rate of 100%, thus realizing the recycling of wastewater.

[0119] (3) The method for recovering valuable elements by leaching battery powder provided by the present invention uses resin desorption to remove copper and uses manganese powder to replace copper in copper-containing desorption solution to obtain high-purity sponge copper. The sponge copper can be sold directly as a by-product. The copper removal waste liquid after copper removal is returned to the second liquid phase for treatment to realize the recovery of copper resources and without the introduction of other impurities.

[0120] (4) The method for recovering valuable elements by aging and leaching battery powder provided by the present invention uses tung oil-based carboxylic acid (TFCA, C). 18 H 30 The O2+diisobutyl ketone co-extraction system preferentially and selectively extracts nickel from the second liquid phase. Combined with the saponification-free extraction zinc removal process, it can obtain nickel sulfate solution in one step, reducing the consumption of liquid alkali, washing acid, etc., and saving production costs.

[0121] (5) The method for recovering valuable elements by leaching battery powder provided by the present invention preferably uses P507 extraction to separate zinc from the nickel-copper-zinc first back-extraction solution to prepare high-purity zinc sulfate. Electrolytic zinc product is prepared by electrolyzing the zinc sulfate solution, thereby realizing the comprehensive utilization of zinc resources.

[0122] (6) The method for recovering valuable elements by leaching battery powder in this invention separates calcium and magnesium from the first raffinate, reducing the impact of calcium and magnesium on the equipment during lithium evaporation and lithium extraction, and reducing the loss of lithium carried away by calcium and magnesium slag; and uses cobalt removal resin to adsorb cobalt, and then adjusts the calcium and magnesium-containing solution generated by the cobalt removal treatment to obtain magnesium hydroxide slag and magnesium removal liquid, and returns the cobalt sulfate solution from the cobalt removal resin to the third extraction, so that valuable metals such as nickel, cobalt, manganese, and lithium are basically recovered.

[0123] (7) The method for recovering valuable elements by leaching battery powder provided by the present invention shortens the overall extraction process: the nickel extraction process is prioritized and the cobalt and manganese extraction process is completed, which shortens the extraction process, reduces the consumption of auxiliary materials such as acid and liquid alkali at the back end, and reduces production costs. Attached Figure Description

[0124] Figure 1 This is a schematic diagram of the leaching process in the battery powder aging and leaching method for recovering valuable elements provided in Embodiment 1 of the present invention.

[0125] Figure 2 This is a schematic diagram of the extraction process in the battery powder aging and leaching method for recovering valuable elements provided in Embodiment 1 of the present invention. Detailed Implementation

[0126] To facilitate understanding of the present invention, the following embodiments are provided. Those skilled in the art should understand that these embodiments are merely illustrative and should not be construed as limiting the scope of the invention.

[0127] It should be understood that the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0128] Example 1

[0129] This embodiment provides a method for leaching and recovering valuable elements through a battery powder curing reaction. See the flowchart for details. Figures 1-2 The method includes the following steps:

[0130] (1) Weigh 1 kg of battery powder, 57 g of sulfur powder and 1200 g of concentrated sulfuric acid (mass percentage concentration > 93%) respectively; stir and mix the battery powder, sulfur powder and concentrated sulfuric acid evenly, heat to 90°C and ripen for 10 h to obtain the ripened material.

[0131] Water was added to the matured material to adjust the liquid-solid ratio to 3 ml: 1 g. The mixture was stirred and leached at room temperature (25°C) for 1 hour, then filtered to obtain a leachate (nickel cobalt manganese lithium sulfate leachate) and a first leaching residue (mainly carbon residue). The first leaching residue was then slurried and washed to obtain carbon residue and washing water, which was returned to the leachate.

[0132] (2) The mixed leachate and the calcined battery powder (calcination temperature 450℃, time 5h, the amount of calcined battery powder added is 1.1 times the theoretical consumption required to convert the residual acid into salt) are subjected to the first conditioning treatment for 1.5h and then filtered to obtain the first liquid phase (i.e., the filter liquid) and battery powder residue. The obtained first liquid phase is added with manganese carbonate and hydrogen peroxide to adjust the pH and remove iron and aluminum to remove impurities. The pH is controlled between 5.0 and 6.5 and the reaction time is 1h. The reaction material is filtered to obtain the second liquid phase and filter residue. The filter residue is washed by slurry washing. The endpoint pH of the slurry washing is 2.5. Then iron and aluminum slag and washing water are obtained. The washing water is recycled to the leachate in step (1).

[0133] (3) The second liquid phase uses the first extraction system to extract nickel, zinc, copper and cobalt. The mass percentage of TFCA in the first extraction system is 20 wt%, the mass percentage of diisobutyl ketone is 10 wt%, and the remainder is sulfonated kerosene. The volume ratio (i.e. volume flow rate ratio) of the first extraction system and the second liquid phase is 3:1. The first extraction system is treated with 30 wt% liquid alkali for primary saponification, with a saponification rate of 40%, and undergoes 8 stages of first extraction. Then, the first washing is performed. The volume ratio of the first extraction system and the washing acid in the first washing is 20:1. The washing acid is 0.5 mol / L sulfuric acid, and the first washing stage is 6 stages. Then, the first back-extraction is performed. The back-extraction acid in the first back-extraction is 2 mol / L sulfuric acid, and the first back-extraction stage is 7 stages. Then, the first iron removal stage and the first clarification stage are performed. The first extraction yields the first raffinate, and the first back-extraction yields the first back-extraction solution containing nickel, copper and zinc.

[0134] (4) The first back-extraction solution containing nickel, copper and zinc is subjected to copper removal by resin. The resin is a copper removal resin (specifically model LSC-495). After passing through the resin, the copper content of the first back-extraction solution containing nickel, copper and zinc is reduced to below 1 mg / L. It is then analyzed by 1.68 mol / L sulfuric acid to obtain a copper-containing eluent. The copper-containing eluent is then subjected to copper removal by displacement with manganese powder. The amount of manganese powder added is 0.95 times the molar copper content in the copper-containing eluent to obtain sponge copper. The copper removal waste liquid after copper removal by displacement with manganese powder is mixed into the second liquid phase for manganese recovery.

[0135] The liquid phase after copper removal from the resin is called the copper-removed liquid. This copper-removed liquid enters an extraction system for zinc removal. A second extraction system is used for zinc removal, in which P507 comprises 8 wt% of zinc and the remainder is sulfonated kerosene. The second extraction system is not saponified before the second extraction. The second extraction has 8 stages, and the volume ratio of the second extraction system to the copper-removed liquid is 1.0:1. A second washing is then performed, in which the volume ratio of the second extraction system to the washing acid is 30:1, and the washing acid is 0.4 mol / L sulfuric acid. The second washing has 5 stages. A second back-extraction is then performed, using 4 mol / L sulfuric acid as the back-extraction acid. The second back-extraction also has 5 stages. Finally, a third-stage second clarification is performed. After the second extraction, a nickel sulfate solution is obtained; after the second back-extraction, a zinc sulfate solution is obtained. The zinc sulfate solution is then electrolyzed to obtain electrolytic zinc.

[0136] (5) The first raffinate is used to extract calcium, magnesium, cobalt, and manganese using a third extraction system. The third extraction system contains 22 wt% C272, 3 wt% TBP (tributyl phosphate), and the remainder is sulfonated kerosene. The saponification rate of the third extraction system is 42%, the volume ratio of the third extraction system to the first raffinate is 5:1, and the third extraction process has 7 stages. A lithium-containing sodium solution (the third raffinate) is obtained from the third extraction. This lithium-containing sodium solution is then used to prepare lithium carbonate via MVR evaporation and carbonation.

[0137] Then, a third wash is performed, using a 0.4 mol / L hydrochloric acid solution as the washing acid. The volume ratio of the third extraction system to the washing acid in the third wash is 50:1. The third wash produces a cobalt-manganese-containing calcium-magnesium chloride solution. This solution is then treated with a cobalt-removing resin, and the resin is further analyzed to obtain a cobalt sulfate solution. The cobalt-removal treatment also produces a calcium-magnesium solution. This solution is adjusted to pH 13.5 with the addition of alkali to precipitate calcium and magnesium. The resulting mixed system is then filtered to obtain calcium-magnesium hydroxide slag and a magnesium-removed liquid. The magnesium-removed liquid is used as an alkali for saponification.

[0138] Then, the process proceeds sequentially through the third clarification stage 1, the third back-extraction stage 5, the third anti-iron stage 3, and the fourth clarification stage 2. The third back-extraction uses a sulfuric acid solution with a concentration of 2.5 mol / L, yielding a cobalt-manganese sulfate solution.

[0139] There is no specific order between steps (4) and (5).

[0140] The content of each element in the second liquid phase in this embodiment is shown in Table 1.

[0141] Table 1

[0142] element nickel cobalt manganese lithium calcium magnesium fluorine Zinc copper content 45g / L 22g / L 20g / L 9g / L 30mg / L 100mg / L 200mg / L 35mg / L 70mg / L

[0143] The content of each element in the first raffinate in this embodiment is shown in Table 2.

[0144] Table 2

[0145]

[0146] The composition of the nickel-copper-zinc first back-extraction solution in this embodiment is shown in Table 3.

[0147] Table 3

[0148] element nickel cobalt manganese lithium calcium magnesium Zinc copper content 112g / L 17.5g / L 0.02g / L 1.3 mg / L 0.4 mg / L 0.2 mg / L 82mg / L 150mg / L

[0149] The composition of the nickel sulfate solution in this embodiment is shown in Table 4.

[0150] Table 4

[0151] element nickel cobalt manganese lithium calcium magnesium Zinc copper content 111g / L 17.4g / L 0.02g / L 1.25 mg / L 0.3 mg / L 0.2 mg / L 1mg / L 0.1 mg / L

[0152] The composition of the zinc sulfate solution in this embodiment is shown in Table 5.

[0153] Table 5

[0154] element Zinc nickel cobalt iron content 185g / L 0.2 mg / L 4.9 mg / L 1.5 mg / L

[0155] The composition of the cobalt manganese sulfate solution in this embodiment is shown in Table 6.

[0156] Table 6

[0157] element cobalt manganese lithium iron magnesium calcium content 53g / L 65g / L 1mg / L 1.2 mg / L 1.4 mg / L 1.7 mg / L

[0158] The composition of the calcium magnesium chloride solution in this embodiment is shown in Table 7.

[0159] Table 7

[0160] element cobalt manganese calcium magnesium lithium content 100mg / L 10mg / L 15.5g / L 36.5g / L 1.5g / L

[0161] The composition of nickel, cobalt, manganese and lithium in the first leaching residue in this embodiment is shown in Table 8.

[0162] Table 8

[0163] element nickel cobalt manganese lithium mass percentage 0.17％ 0.12％ 0.13％ 0.02％

[0164] The composition of nickel, cobalt, manganese and lithium in the iron-aluminum slag in this embodiment is shown in Table 9.

[0165] Table 9

[0166] element nickel cobalt manganese lithium mass percentage 0.19％ 0.15％ 0.11％ 0.02％

[0167] Example 2

[0168] This embodiment provides a method for recovering valuable elements by leaching through a battery powder aging reaction, the method comprising the following steps:

[0169] (1) Weigh out 1 kg of battery powder, 57 g of sulfur powder and 1000 g of concentrated sulfuric acid (mass percentage concentration > 93%).

[0170] Battery powder, sulfur powder and concentrated sulfuric acid are stirred and mixed evenly, and heated to 110°C for 10 hours to mature the material.

[0171] Water was added to the matured material to adjust the liquid-solid ratio to 3 ml: 1 g. The mixture was stirred and leached at room temperature (25°C) for 1 hour. After filtration, a leachate (nickel cobalt manganese lithium sulfate leachate) and a first leaching residue (mainly carbon residue) were obtained. The first leaching residue was then slurried and washed to obtain carbon residue and washing water. The washing water was returned to the leachate.

[0172] (2) The mixed leachate and the calcined battery powder (calcination temperature 450℃, time 5h, the amount of calcined battery powder added is 1.1 times the theoretical consumption required to convert the residual acid into salt) are subjected to a first conditioning treatment for 1h and then filtered to obtain the first liquid phase. The first liquid phase, i.e. the filter liquid, is added with manganese carbonate and hydrogen peroxide to adjust the pH and remove iron and aluminum to remove impurities. The pH is controlled between 5.0 and 6.0 and the reaction time is 1h. The reaction material is filtered to obtain the second liquid phase and filter residue. The filter residue is washed by slurry. The endpoint pH of the slurry washing is 4.0. Then iron and aluminum slag and washing water are obtained. The washing water is recycled to the leachate in step (1).

[0173] (3) The second liquid phase uses the first extraction system to extract nickel, zinc, copper and cobalt. The mass percentage of TFCA in the first extraction system is 25 wt%, the mass percentage of diisobutyl ketone is 5 wt%, and the remainder is sulfonated kerosene. The volume ratio (i.e., volume flow rate ratio) of the first extraction system and the second liquid phase is 6:1. The first extraction system is treated with 35 wt% liquid alkali for primary saponification, with a saponification rate of 50%, and undergoes 8 stages of first extraction. Then, the first washing is performed. The volume ratio of the first extraction system to the washing acid in the first washing is 60:1. The washing acid is 0.8 mol / L sulfuric acid, and the first washing stage is 6 stages. Then, the first back-extraction is performed. The back-extraction acid in the first back-extraction is 5 mol / L sulfuric acid, and the first back-extraction stage is 7 stages. Then, the first iron removal stage and the first clarification stage are performed. The first extraction yields the first raffinate, and the first back-extraction yields the first back-extraction solution containing nickel, copper and zinc.

[0174] (4) The first back-extraction solution containing nickel, copper and zinc is subjected to copper removal by resin. The resin is a copper removal resin (specifically model LSC-495). After passing through the resin, the copper content of the first back-extraction solution containing nickel, copper and zinc is reduced to below 1 mg / L. It is then analyzed by 2 mol / L sulfuric acid to obtain a copper-containing eluent. The copper-containing eluent is then subjected to copper removal by displacement with manganese powder. The amount of manganese powder added is 0.9 times the molar copper content in the copper-containing eluent to obtain sponge copper. The copper removal waste liquid after copper removal by displacement with manganese powder is mixed into the second liquid phase for manganese recovery.

[0175] The liquid phase after copper removal from the resin is called the copper-removed liquid. This copper-removed liquid enters an extraction system for zinc removal. A second extraction system is used for zinc removal, in which P507 comprises 10 wt% and the remainder is sulfonated kerosene. The second extraction system is not saponified before the second extraction. The second extraction has 7 stages, and the volume ratio of the second extraction system to the copper-removed liquid is 1.2:1. A second washing is then performed, in which the volume ratio of the second extraction system to the washing acid is 20:1, and the washing acid is 0.5 mol / L sulfuric acid. The second washing has 6 stages. A second back-extraction is then performed, using 4 mol / L sulfuric acid as the back-extraction acid. The second back-extraction has 7 stages. A second clarification is then performed. After the second extraction, a nickel sulfate solution is obtained; after the second back-extraction, a zinc sulfate solution is obtained. The zinc sulfate solution is then electrolyzed to obtain electrolytic zinc.

[0176] (5) The first raffinate is used to extract calcium, magnesium, cobalt, and manganese using a third extraction system. The third extraction system contains 20 wt% C272, 3 wt% TBP (tributyl phosphate), and the remainder is sulfonated kerosene. The saponification rate of the third extraction system is 40%, the volume ratio of the third extraction system to the first raffinate is 6:1, and the third extraction has 6 stages. A lithium-containing sodium solution (the third raffinate) is obtained from the third extraction. This lithium-containing sodium solution is then used to prepare lithium carbonate via MVR evaporation and carbonization.

[0177] Then, a third wash is performed, using a 0.3 mol / L hydrochloric acid solution as the washing acid. The volume ratio of the third extraction system to the washing acid in the third wash is 40:1. The third wash produces a cobalt-manganese-containing calcium-magnesium chloride solution. This solution is then treated with a cobalt-removing resin, and the resin is further analyzed to obtain a cobalt sulfate solution. The cobalt-removal treatment also produces a calcium-magnesium solution. This solution is adjusted to pH 13.2 with the addition of alkali to precipitate calcium and magnesium. The resulting mixed system is then filtered to obtain calcium-magnesium hydroxide slag and a magnesium-removed liquid. The magnesium-removed liquid is used as an alkali for saponification.

[0178] Then, the process proceeds sequentially through the third clarification stage 1, the third back-extraction stage 4, the third anti-iron stage 2, and the fourth clarification stage 3. The third back-extraction uses a sulfuric acid solution with a concentration of 2 mol / L, yielding a cobalt-manganese sulfate solution.

[0179] There is no specific order between steps (4) and (5).

[0180] Example 3

[0181] This embodiment provides a method for recovering valuable elements by leaching through a battery powder aging reaction, the method comprising the following steps:

[0182] (1) Weigh out 1 kg of battery powder, 57 g of sulfur powder and 1200 g of concentrated sulfuric acid (mass percentage concentration > 93%) respectively.

[0183] Battery powder, sulfur powder and concentrated sulfuric acid are stirred and mixed evenly, and heated to 90°C for 20 hours to mature the material.

[0184] Water was added to the matured material to adjust the liquid-solid ratio to 5 ml: 1 g. The mixture was stirred and leached at room temperature (25°C) for 1 hour. After filtration, a leachate (nickel cobalt manganese lithium sulfate leachate) and a first leaching residue (mainly carbon residue) were obtained. The first leaching residue was then slurried and washed to obtain carbon residue and washing water. The washing water was returned to the leachate.

[0185] (2) The mixed leachate and the calcined battery powder (calcination temperature 500℃, time 1h, the amount of calcined battery powder added is 1.2 times the theoretical consumption required to convert the residual acid into salt) are subjected to the first conditioning treatment for 1h and then filtered to obtain the first liquid phase. The first liquid phase, i.e. the filter liquid, is added with manganese carbonate and hydrogen peroxide to adjust the pH and remove iron and aluminum to remove impurities. The pH is controlled between 5.5 and 6.5 and the reaction time is 1.5h. The reaction material is filtered to obtain the second liquid phase and filter residue. The filter residue is washed by slurry. The endpoint pH of the slurry washing is 2.3. Then iron and aluminum slag and washing water are obtained. The washing water is recycled to the leachate in step (1).

[0186] (3) The second liquid phase uses the first extraction system to extract nickel, zinc, copper and cobalt. The mass percentage of TFCA in the first extraction system is 22 wt%, the mass percentage of diisobutyl ketone is 8 wt%, and the remainder is sulfonated kerosene. The volume ratio (i.e., volume flow rate ratio) of the first extraction system and the second liquid phase is 4:1. The first extraction system uses 32 wt% liquid alkali for primary saponification treatment, with a saponification rate of 45%, and performs 8 stages of first extraction. Then, the first washing is performed. The volume ratio of the first extraction system to the washing acid in the first washing is 30:1. The washing acid is 0.6 mol / L sulfuric acid, and the number of stages of the first washing is 6. Then, the first back-extraction is performed. The back-extraction acid in the first back-extraction is 4 mol / L sulfuric acid, and the number of stages of the first back-extraction is 7. Then, the first anti-iron stage 2 and the first clarification stage 3 are performed. Among them, the first extraction yields the first raffinate, and the first back-extraction yields the first back-extraction solution containing nickel, copper and zinc.

[0187] (4) The first back-extraction solution containing nickel, copper and zinc is subjected to copper removal by resin. The resin is a copper removal resin (specifically model LSC-495). After passing through the resin, the copper content of the first back-extraction solution containing nickel, copper and zinc is reduced to below 1 mg / L. It is then analyzed by 1 mol / L sulfuric acid to obtain a copper-containing eluent. The copper-containing eluent is then subjected to copper removal by displacement with manganese powder. The amount of manganese powder added is 1 times the molar content of copper in the copper-containing eluent to obtain sponge copper. The copper removal waste liquid after copper removal by displacement with manganese powder is mixed into the second liquid phase for manganese recovery.

[0188] The liquid phase after copper removal from the resin is called the copper-removed liquid. This copper-removed liquid enters an extraction system for zinc removal. A second extraction system is used for zinc removal, in which P507 comprises 3 wt% of zinc and the remainder is sulfonated kerosene. The second extraction system is not saponified before the second extraction. The second extraction has 6 stages, and the volume ratio of the second extraction system to the copper-removed liquid is 0.8:1. A second washing is then performed, in which the volume ratio of the second extraction system to the washing acid is 60:1, and the washing acid is 0.4 mol / L sulfuric acid. The second washing has 4 stages. A second back-extraction is then performed, using 3 mol / L sulfuric acid as the back-extraction acid. The second back-extraction has 6 stages. A third stage of second clarification is then performed. After the second extraction, a nickel sulfate solution is obtained; after the second back-extraction, a zinc sulfate solution is obtained. The zinc sulfate solution is then electrolyzed to obtain electrolytic zinc.

[0189] (5) The first raffinate is used to extract calcium, magnesium, cobalt, and manganese using a third extraction system. The third extraction system contains 21 wt% C272, 4 wt% TBP (tributyl phosphate), and the remainder is sulfonated kerosene. The saponification rate of the third extraction system is 45%, the volume ratio of the third extraction system to the first raffinate is 4:1, and the third extraction process has 8 stages. A lithium-containing sodium solution (the third raffinate) is obtained from the third extraction. This lithium-containing sodium solution is then used to prepare lithium carbonate via MVR evaporation and carbonization.

[0190] Then, a third wash is performed, using a 0.6 mol / L hydrochloric acid solution as the washing acid. The volume ratio of the third extraction system to the washing acid in the third wash is 60:1. The third wash produces a cobalt-manganese-containing calcium magnesium chloride solution. This solution undergoes cobalt removal treatment with a cobalt removal resin, followed by resin analysis to obtain a cobalt sulfate eluent. The cobalt removal treatment also produces a calcium magnesium solution. This calcium magnesium solution is adjusted to pH 14 with the addition of alkali to precipitate calcium and magnesium. The resulting mixed system is then filtered to obtain calcium magnesium hydroxide slag and a magnesium-removed liquid. The magnesium-removed liquid is used as alkali for saponification.

[0191] Then, the process proceeds sequentially through the third clarification stage 1, the third back-extraction stage 6, the third anti-iron stage 3, and the fourth clarification stage 2. The third back-extraction uses a sulfuric acid solution with a concentration of 3 mol / L, yielding a cobalt-manganese sulfate solution.

[0192] There is no specific order between steps (4) and (5).

[0193] Example 4

[0194] This embodiment provides a method for recovering valuable elements by leaching through a battery powder aging reaction, the method comprising the following steps:

[0195] (1) Weigh out 1 kg of battery powder, 60 g of sulfur powder and 1100 g of concentrated sulfuric acid (mass percentage concentration > 94%) respectively.

[0196] Battery powder, sulfur powder and concentrated sulfuric acid are stirred and mixed evenly, and heated to 140°C for 5 hours to mature the material.

[0197] Water was added to the matured material to adjust the liquid-solid ratio to 2 ml: 1 g. The mixture was stirred and leached at 10 °C for 3 h. After filtration, a leachate (nickel cobalt manganese lithium sulfate leachate) and a first leaching residue (mainly carbon residue) were obtained. The first leaching residue was then slurried and washed to obtain carbon residue and washing water. The washing water was returned to the leachate.

[0198] (2) The mixed leachate and the calcined battery powder (calcination temperature 400℃, time 6h, the amount of calcined battery powder added is 1.15 times the theoretical consumption required to convert the residual acid into salt) are subjected to the first conditioning treatment for 2h and then filtered to obtain the first liquid phase. The first liquid phase, i.e. the filter liquid, is added with manganese carbonate and hydrogen peroxide to adjust the pH and remove iron and aluminum to remove impurities. The pH is controlled between 5.5 and 6.0, and the reaction time is 1.2h. The reaction material is filtered to obtain the second liquid phase and filter residue. The filter residue is washed by slurry. The endpoint pH of the slurry washing is 3.5. Then iron and aluminum slag and washing water are obtained. The washing water is recycled to the leachate in step (1).

[0199] (3) The second liquid phase uses the first extraction system to extract nickel, zinc, copper and cobalt. The mass percentage of TFCA in the first extraction system is 21 wt%, the mass percentage of diisobutyl ketone is 7.5 wt%, and the remainder is sulfonated kerosene. The volume ratio (i.e. volume flow rate ratio) of the first extraction system and the second liquid phase is 3.5:1. The first extraction system uses 25 wt% liquid alkali for primary saponification treatment, with a saponification rate of 40%, and performs 8 stages of first extraction. Then, the first washing is performed. The volume ratio of the first extraction system to the washing acid in the first washing is 50:1. The washing acid is 0.7 mol / L sulfuric acid, and the number of stages of the first washing is 6. Then, the first back-extraction is performed. The back-extraction acid in the first back-extraction is 5 mol / L sulfuric acid, and the number of stages of the first back-extraction is 7. Then, the first anti-iron treatment is performed in 2 stages and the first clarification is performed in 3 stages. The first extraction yields the first raffinate, and the first back-extraction yields the first back-extraction solution containing nickel, copper and zinc.

[0200] (4) The first back-extraction solution containing nickel, copper and zinc is subjected to copper removal by resin. The resin is a copper removal resin (specifically model LSC-495). After passing through the resin, the copper content of the first back-extraction solution containing nickel, copper and zinc is reduced to below 1 mg / L. It is then analyzed by 1.5 mol / L sulfuric acid to obtain a copper-containing eluent. The copper-containing eluent is then subjected to copper removal by displacement with manganese powder. The amount of manganese powder added is 0.92 times the molar copper content in the copper-containing eluent to obtain sponge copper. The copper removal waste liquid after copper removal by displacement with manganese powder is mixed into the second liquid phase for manganese recovery.

[0201] The liquid phase after copper removal from the resin is called the copper-removed liquid. This copper-removed liquid enters an extraction system for zinc removal. A second extraction system is used for zinc removal, in which P507 comprises 5 wt% of zinc and the remainder is sulfonated kerosene. The second extraction system is not saponified before the second extraction. The second extraction has six stages, and the volume ratio of the second extraction system to the copper-removed liquid is 1.0:1. A second washing is then performed, in which the volume ratio of the second extraction system to the washing acid is 40:1, and the washing acid is 0.3 mol / L sulfuric acid. The second washing has six stages. A second back-extraction is then performed, using 3 mol / L sulfuric acid as the back-extraction acid. The second back-extraction has three stages. A second clarification is then performed. After the second extraction, a nickel sulfate solution is obtained; after the second back-extraction, a zinc sulfate solution is obtained. The zinc sulfate solution is then electrolyzed to obtain electrolytic zinc.

[0202] (5) The first raffinate is used to extract calcium, magnesium, cobalt, and manganese using a third extraction system. The third extraction system contains 20 wt% C272, 2 wt% TBP (tributyl phosphate), and the remainder is sulfonated kerosene. The saponification rate of the third extraction system is 40%, the volume ratio of the third extraction system to the first raffinate is 5.5:1, and the third extraction has 6 stages. A lithium-containing sodium solution (the third raffinate) is obtained from the third extraction. This lithium-containing sodium solution is then used to prepare lithium carbonate via MVR evaporation and carbonization.

[0203] Then, a third wash is performed, using a 0.3 mol / L hydrochloric acid solution as the washing acid. The volume ratio of the third extraction system to the washing acid in the third wash is 44:1. The third wash produces a cobalt-manganese-containing calcium magnesium chloride solution. This solution is then treated with a cobalt removal resin, and the resin is further analyzed to obtain a cobalt sulfate solution. The cobalt removal treatment also produces a calcium magnesium solution. The calcium magnesium solution is adjusted to pH 13.5 with the addition of alkali to precipitate calcium and magnesium. The resulting mixed system is then filtered to obtain calcium magnesium hydroxide slag and a magnesium-removed liquid. The magnesium-removed liquid is used as an alkali for saponification.

[0204] Then, the process proceeds sequentially through the third clarification stage 1, the third back-extraction stage 4, the third anti-iron stage 2, and the fourth clarification stage 3. The third back-extraction uses a sulfuric acid solution with a concentration of 2 mol / L, yielding a cobalt-manganese sulfate solution.

[0205] There is no specific order between steps (4) and (5).

[0206] Example 5

[0207] This embodiment provides a method for recovering valuable elements by leaching through a battery powder aging reaction, the method comprising the following steps:

[0208] (1) Weigh out 1 kg of battery powder, 32 g of sulfur powder and 1000 g of concentrated sulfuric acid (mass concentration > 93%) respectively.

[0209] Battery powder, sulfur powder and concentrated sulfuric acid are stirred and mixed evenly, and heated to 100°C for 15 hours to mature the material.

[0210] Water was added to the matured material to adjust the liquid-solid ratio to 3.5 ml: 1 g. The mixture was stirred and leached at 30 °C for 2.5 h. After filtration, a leachate (nickel cobalt manganese lithium sulfate leachate) and a first leaching residue (mainly carbon residue) were obtained. The first leaching residue was then slurried and washed to obtain carbon residue and washing water. The washing water was returned to the leachate.

[0211] (2) The mixed leachate and the calcined battery powder (calcination temperature 420℃, time 1.5h, the amount of calcined battery powder added is 1.2 times the theoretical consumption required to convert the residual acid into salt) are subjected to the first conditioning treatment for 2h and then filtered to obtain the first liquid phase. The first liquid phase, i.e. the filter liquid, is added with manganese carbonate and hydrogen peroxide to adjust the pH and remove iron and aluminum to remove impurities. The pH is controlled between 5.0 and 6.0 and the reaction time is 1.5h. The reaction material is filtered to obtain the second liquid phase and filter residue. The filter residue is washed by slurry. The endpoint pH of the slurry washing is 3.2. Then iron and aluminum slag and washing water are obtained. The washing water is recycled to the leachate in step (1).

[0212] (3) The second liquid phase uses the first extraction system to extract nickel, zinc, copper and cobalt. The mass percentage of TFCA in the first extraction system is 21 wt%, the mass percentage of diisobutyl ketone is 10 wt%, and the remainder is sulfonated kerosene. The volume ratio (i.e., volume flow rate ratio) of the first extraction system and the second liquid phase is 5:1. The first extraction system is treated with 30 wt% liquid alkali for primary saponification, with a saponification rate of 45%, and undergoes 8 stages of first extraction. Then, the first washing is performed. The volume ratio of the first extraction system to the washing acid in the first washing is 30:1. The washing acid is 0.7 mol / L sulfuric acid, and the first washing stage is 6 stages. Then, the first back-extraction is performed. The back-extraction acid in the first back-extraction is 3.5 mol / L sulfuric acid, and the first back-extraction stage is 7 stages. Then, the first iron removal stage and the first clarification stage are performed. The first extraction yields the first raffinate, and the first back-extraction yields the first back-extraction solution containing nickel, copper and zinc.

[0213] (4) The first back-extraction solution containing nickel, copper and zinc is subjected to copper removal by resin. The resin is a copper removal resin (specifically model LSC-495). After passing through the resin, the copper content of the first back-extraction solution containing nickel, copper and zinc is reduced to below 1 mg / L. It is then analyzed by 1.2 mol / L sulfuric acid to obtain a copper-containing eluent. The copper-containing eluent is then subjected to copper removal by displacement with manganese powder. The amount of manganese powder added is 1 times the molar content of copper in the copper-containing eluent to obtain sponge copper. The copper removal waste liquid after copper removal by displacement with manganese powder is mixed into the second liquid phase for manganese recovery.

[0214] The liquid phase after copper removal from the resin is called the copper-removed liquid. This copper-removed liquid enters an extraction system for zinc removal. A second extraction system is used for zinc removal, in which P507 comprises 5 wt% by mass, and the remainder is sulfonated kerosene. The second extraction system is not saponified before the second extraction. The second extraction has 7 stages, and the volume ratio of the second extraction system to the copper-removed liquid is 0.9:1. A second washing is then performed, in which the volume ratio of the second extraction system to the washing acid is 60:1, and the washing acid is 0.3 mol / L sulfuric acid. The second washing has 5 stages. A second back-extraction is then performed, using 3 mol / L sulfuric acid as the back-extraction acid. The second back-extraction has 6 stages. Finally, a third-stage second clarification is performed. After the second extraction, a nickel sulfate solution is obtained; after the second back-extraction, a zinc sulfate solution is obtained. The zinc sulfate solution is then electrolyzed to obtain electrolytic zinc.

[0215] (5) The first raffinate is used to extract calcium, magnesium, cobalt, and manganese using a third extraction system. The third extraction system contains 24 wt% C272, 1 wt% TBP (tributyl phosphate), and the remainder is sulfonated kerosene. The saponification rate of the third extraction system is 45%, the volume ratio of the third extraction system to the first raffinate is 5:1, and the third extraction has 8 stages. A lithium-containing sodium solution (the third raffinate) is obtained from the third extraction. This lithium-containing sodium solution is then used to prepare lithium carbonate via MVR evaporation and carbonation.

[0216] Then, a third wash is performed, using a 0.6 mol / L hydrochloric acid solution as the washing acid. The volume ratio of the third extraction system to the washing acid in the third wash is 40:1. The third wash produces a cobalt-manganese-containing calcium-magnesium chloride solution. This solution undergoes cobalt removal treatment with a cobalt removal resin, followed by resin analysis to obtain a cobalt sulfate eluent. The cobalt removal treatment also produces a calcium-magnesium solution. This calcium-magnesium solution is adjusted to pH 13.5 with the addition of alkali to precipitate calcium and magnesium. The resulting mixed system is then filtered to obtain calcium-magnesium hydroxide slag and a magnesium-removed liquid. The magnesium-removed liquid is used as alkali for saponification.

[0217] Then, the process proceeds sequentially through the third clarification stage 1, the third back-extraction stage 6, the third anti-iron stage 2, and the fourth clarification stage 2. The third back-extraction uses a sulfuric acid solution with a concentration of 2.2 mol / L, yielding a cobalt-manganese sulfate solution.

[0218] There is no specific order between steps (4) and (5).

[0219] The leaching rate data for Examples 1 to 5 are shown in Table 10.

[0220] Table 10

[0221]

[0222] Example 6

[0223] This embodiment provides a method for recovering valuable elements by leaching and curing battery powder. Except for the fact that the mass percentage of TFCA in the first extraction system is 15 wt%, the method is the same as that in Example 1, and will not be repeated here.

[0224] The composition of the nickel-copper-zinc first back-extraction solution in this embodiment is shown in Table 11.

[0225] Table 11

[0226] element nickel cobalt manganese lithium calcium magnesium Zinc copper content 112g / L 17.5g / L 0.08g / L 3.3 mg / L 1.2 mg / L 0.6 mg / L 82mg / L 150mg / L

[0227] The results in the table above show that a low TFCA content will affect the impurity content, resulting in a low extractant load and a high level of impurities in the first back-extraction solution containing nickel, copper, and zinc.

[0228] Example 7

[0229] This embodiment provides a method for recovering valuable elements by leaching and curing battery powder. Except for the fact that the mass percentage of TFCA in the first extraction system is 28 wt%, the method is the same as that in Example 1, and will not be repeated here.

[0230] The composition of the nickel-copper-zinc first back-extraction solution in this embodiment is shown in Table 12.

[0231] Table 12

[0232] element nickel cobalt manganese lithium calcium magnesium Zinc copper content 111.9g / L 17.4g / L 0.02g / L 1.3 mg / L 0.4 mg / L 0.2 mg / L 82mg / L 150mg / L

[0233] The results in the table above show that the TFCA content is high, the extractant loading is high, and the organic impurities are comparable to those in Example 1. However, the high extractant content will result in a lower extractant utilization rate and higher initial investment costs.

[0234] Example 8

[0235] This embodiment provides a method for recovering valuable elements by leaching and curing battery powder. The method is the same as in Example 1 except that P507 is replaced with P204 in the second extraction system, and will not be described again here.

[0236] The composition of the zinc sulfate solution in this embodiment is shown in Table 13.

[0237] Table 13

[0238] element Zinc nickel cobalt iron content 185g / L 20.9 mg / L 0.75g / L 1.5 mg / L

[0239] Replacing P507 with P204 will affect the purity of the zinc sulfate solution, leading to an increase in the content of metals such as cobalt and nickel, and will be detrimental to the downstream zinc sulfate electrolysis.

[0240] Comparative Example 1

[0241] This comparative example provides a method for recovering valuable elements by leaching and curing battery powder. Except for not performing the curing reaction, the method is the same as that in Example 1, and will not be repeated here.

[0242] This comparative example does not undergo a ripening reaction, making subsequent processes difficult and hindering the effective recovery of each element.

[0243] Comparative Example 2

[0244] This comparative example provides a method for recovering valuable elements by leaching battery powder during aging. The method is the same as in Example 1 except that sulfur powder is not added during the aging reaction and only concentrated sulfuric acid is used. It will not be described again here.

[0245] In this comparative example, only concentrated sulfuric acid was added, making the reduction reaction difficult to proceed.

[0246] Comparative Example 3

[0247] This comparative example provides a method for recovering valuable elements by leaching battery powder during aging. Except for the absence of concentrated sulfuric acid in the aging reaction and the use of only sulfur powder, the method is the same as that in Example 1 and will not be repeated here.

[0248] In this comparative example, only sulfur powder was added, making the reduction reaction difficult to proceed.

[0249] Comparative Example 4

[0250] This comparative example provides a method for recovering valuable elements by leaching and curing battery powder. The method is the same as that in Example 1 except that no impurity removal treatment (i.e., removal of iron and aluminum) is performed, and will not be described again here.

[0251] Without impurity removal in this comparative example, the subsequent first extraction process is difficult to carry out, making it difficult to separate the elements.

[0252] The present invention has been illustrated with the above embodiments to illustrate its detailed features, but the present invention is not limited to the above detailed features, that is, it does not mean that the present invention must rely on the above detailed features to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions for the selected technical features, additions of auxiliary technical features, and selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A method for recovering valuable elements by leaching and curing battery powder, characterized in that, The method includes: (1) Mix sulfur powder, concentrated sulfuric acid and battery powder, and carry out a aging reaction to obtain aging material; the aging material is leached to obtain leachate; the leaching solvent is water; (2) The leachate in step (1) undergoes a first conditioning treatment and solid-liquid separation to obtain a first liquid phase; the first liquid phase is then purified and separated to obtain a second liquid phase. (3) The second liquid phase is subjected to a first extraction to obtain a first raffinate, and the extract obtained from the first extraction is subjected to a first back-extraction to obtain a first back-extraction solution containing nickel, copper, and zinc; the first extraction system in the first extraction includes tung oil-based carboxylic acid, a co-extractant, and an organic solvent; the co-extractant includes any one or a combination of at least two of pyridine ester, β-diketone, diisobutyl ketone, 4,5-dimethylimidazole, or 1,2-dialkylimidazole; the mass percentage of tung oil-based carboxylic acid in the first extraction system is 20wt%~25wt%; the mass percentage of the co-extractant in the first extraction system is 5wt%~10wt%; (4) The first back-extraction solution containing nickel, copper and zinc is subjected to copper removal and zinc removal by a second extraction in sequence. The second raffinate obtained is a nickel sulfate solution. The second extract obtained by the second extraction to remove zinc is subjected to a second back-extraction to obtain a zinc sulfate solution. (5) The first raffinate is subjected to a third extraction to obtain a third raffinate solution containing sodium lithium. The third extract obtained from the third extraction is subjected to a third back-extraction to obtain a cobalt manganese sulfate solution. There is no specific order between steps (4) and (5).

2. The method according to claim 1, characterized in that, The battery powder mentioned in step (1) is a ternary lithium-ion battery cathode powder.

3. The method according to claim 1, characterized in that, The total mass percentage of nickel, cobalt, and manganese in the battery powder is 30wt%~35wt%.

4. The method according to claim 1, characterized in that, The sulfur powder is industrial sulfur powder with a purity greater than 99 wt%.

5. The method according to claim 1, characterized in that, The concentrated sulfuric acid has a mass fraction of ≥93wt%.

6. The method according to claim 1, characterized in that, The temperature of the ripening reaction in step (1) is 90~140℃.

7. The method according to claim 1, characterized in that, The ripening reaction takes 5 to 20 hours.

8. The method according to claim 1, characterized in that, The mass ratio of battery powder to sulfur powder is 15~32:

1.

9. The method according to claim 1, characterized in that, The mass ratio of concentrated sulfuric acid to battery powder is 0.9~1.4:

1.

10. The method according to claim 1 or 2, characterized in that, The leaching time is 1 to 3 hours.

11. The method according to claim 1 or 2, characterized in that, The leaching temperature is 10~30℃.

12. The method according to claim 1 or 2, characterized in that, The metal element composition of the leachate includes: Ni: 40-60 g / L, Co: 20-30 g / L, Mn: 15-25 g / L, and Li: 10-16 g / L.

13. The method according to claim 1 or 2, characterized in that, The liquid-to-solid ratio of the leaching is 2-5 ml: 1 g.

14. The method according to claim 1 or 2, characterized in that, Carbon residue is separated during the leaching process.

15. The method according to claim 1, characterized in that, The first conditioning process in step (2) includes: mixing the leachate and the calcined battery powder to neutralize the residual acid.

16. The method according to claim 15, characterized in that, The calcined battery powder is obtained by calcining pretreatment of battery powder.

17. The method according to claim 16, characterized in that, The temperature of the calcination pretreatment is 400~500℃.

18. The method according to claim 16, characterized in that, The roasting pretreatment time is 1-6 hours.

19. The method according to claim 15, characterized in that, In the first conditioning process, the amount of battery powder added after calcination is 1.1 to 1.2 times the theoretical amount required to convert the residual acid into salt.

20. The method according to claim 1 or 2, characterized in that, The first adjustment process takes 1 to 2 hours.

21. The method according to claim 1 or 2, characterized in that, In step (2), the solid-liquid separation after the first adjustment treatment is pressure filtration.

22. The method according to claim 1, characterized in that, The impurity removal described in step (2) includes mixing an oxidant, an alkali, and a first liquid phase to remove iron and aluminum.

23. The method according to claim 22, characterized in that, The oxidizing agent includes hydrogen peroxide.

24. The method according to claim 22, characterized in that, The alkali includes manganese carbonate.

25. The method according to claim 22, characterized in that, The pH value during the impurity removal process is 5~6.

5.

26. The method according to claim 22, characterized in that, The solid phase obtained after impurity removal and solid-liquid separation is then subjected to pulping and washing.

27. The method according to claim 26, characterized in that, The endpoint pH of the pulping wash is 2-4.

28. The method according to claim 1 or 2, characterized in that, The organic solvent in the first extraction system is sulfonated kerosene.

29. The method according to claim 1 or 2, characterized in that, The saponification rate of the first extraction system is 40%~50%.

30. The method according to claim 1 or 2, characterized in that, The volume ratio of the first extraction system to the second liquid phase is 3~6:

1.

31. The method according to claim 1 or 2, characterized in that, The first back-extraction uses a sulfuric acid solution.

32. The method according to claim 31, characterized in that, The concentration of the sulfuric acid solution in the first back-extraction is 2~5 mol / L.

33. The method according to claim 1 or 2, characterized in that, Between the first extraction and the first back-extraction, a first washing is also included.

34. The method according to claim 33, characterized in that, The washing acid used in the first wash includes a sulfuric acid solution.

35. The method according to claim 34, characterized in that, In the first washing process, the volume ratio of the first extraction system to the washing acid is 20~60:

1.

36. The method according to claim 35, characterized in that, The concentration of the washing acid in the first wash is 0.5~0.8 mol / L.

37. The method according to claim 1, characterized in that, The copper removal process in step (4) includes copper removal with resin.

38. The method according to claim 37, characterized in that, The copper removal process includes: removing copper from the first back-extraction solution with copper-removing resin to obtain a copper-removed solution; and using a desorbing acid to desorb the copper-removed resin to obtain a copper-containing desorbed solution.

39. The method according to claim 38, characterized in that, The acid used in the analysis is sulfuric acid; The concentration of the acid used for analysis is 1~2 mol / L.

40. The method according to claim 38, characterized in that, The copper-containing solution was subjected to manganese powder replacement to remove copper, thus preparing sponge copper.

41. The method according to claim 40, characterized in that, The amount of manganese powder added in the copper removal process is 0.9 to 1 times the molar content of copper in the copper-containing solution.

42. The method according to claim 40, characterized in that, The copper removal process using manganese powder involves mixing manganese powder and a copper-containing analytical solution to remove copper, resulting in sponge copper and copper removal waste liquid.

43. The method according to claim 1, characterized in that, The copper-removed liquid described in step (4) is subjected to a second extraction in a second extraction system to remove zinc.

44. The method according to claim 43, characterized in that, The second extraction system includes organophosphate compounds and solvent oil.

45. The method according to claim 44, characterized in that, The organophosphate compounds in the second extraction system include any one or a combination of at least two of P204, P507, or C272.

46. ​​The method according to claim 44, characterized in that, The mass percentage of organophosphate compounds in the second extraction system is 2wt%~10wt%.

47. The method according to claim 43, characterized in that, The second extraction system does not undergo saponification.

48. The method according to claim 44, characterized in that, The solvent oil is sulfonated kerosene.

49. The method according to claim 43, characterized in that, The volume ratio of the second extraction system to the copper-removed liquid is 0.8~1.2:

1.

50. The method according to claim 1 or 2, characterized in that, The second back-extraction uses a sulfuric acid solution.

51. The method according to claim 50, characterized in that, The concentration of the sulfuric acid solution used in the second back-extraction is 3-5 mol / L.

52. The method according to claim 1 or 2, characterized in that, A second washing process is also included between the second extraction and the second back-extraction.

53. The method according to claim 52, characterized in that, The washing acid used in the second washing process includes a sulfuric acid solution.

54. The method according to claim 53, characterized in that, In the second washing process, the volume ratio of the second extraction system to the washing acid is 20~60:

1.

55. The method according to claim 53, characterized in that, The concentration of the washing acid in the second wash is 0.3~0.5 mol / L.

56. The method according to claim 1, characterized in that, The third extraction system described in step (5) includes organophosphate compounds and solvent oil.

57. The method according to claim 56, characterized in that, The organophosphate compounds in the third extraction system include any one or a combination of at least two of P507, C272, P204, P227, or TBP.

58. The method according to claim 57, characterized in that, The mass percentage of organophosphate compounds in the third extraction system is 20wt%~25wt%.

59. The method according to claim 56, characterized in that, The saponification rate of the third extraction system is 40%~45%.

60. The method according to claim 56, characterized in that, The solvent oil in the third extraction system is sulfonated kerosene.

61. The method according to claim 56, characterized in that, The volume ratio of the third extraction system to the first raffinate is 4~6:

1.

62. The method according to claim 1 or 2, characterized in that, The third back-extraction uses a sulfuric acid solution.

63. The method according to claim 62, characterized in that, The concentration of the sulfuric acid solution used in the third back-extraction is 2-3 mol / L.

64. The method according to claim 1 or 2, characterized in that, A third washing is also included between the third extraction and the third back-extraction.

65. The method according to claim 64, characterized in that, The washing acid used in the third wash includes a hydrochloric acid solution.

66. The method according to claim 65, characterized in that, The volume ratio of the third extraction system to the washing acid in the third washing process is 40~60:

1.

67. The method according to claim 65, characterized in that, The concentration of the washing acid in the third wash is 0.3~0.6 mol / L.

68. The method according to claim 1 or 2, characterized in that, Lithium carbonate is prepared from the lithium-containing sodium solution via MVR evaporation and carbonization process.

69. The method according to claim 64, characterized in that, The third wash produces a cobalt-manganese-calcium-magnesium chloride solution.

70. The method according to claim 69, characterized in that, The cobalt-containing manganese calcium magnesium chloride solution is subjected to cobalt removal treatment with cobalt removal resin and then the cobalt removal resin is analyzed to obtain a cobalt sulfate solution.

71. The method according to claim 70, characterized in that, The cobalt removal process also produces a calcium- and magnesium-containing solution.

72. The method according to claim 71, characterized in that, The calcium-magnesium solution is adjusted to a pH of 13 or higher by adding alkali to precipitate calcium and magnesium. The resulting mixed system is then separated into solid and liquid components to obtain calcium-magnesium hydroxide slag and magnesium-removed liquid.

73. The method according to claim 72, characterized in that, The magnesium-removed liquid is used as an alkali for saponification.

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