Method for curing, leaching and recycling valuable elements from battery powder

Abstract

The invention provides a method for recycling valuable elements by curing and leaching battery powder, which comprises the following steps: mixing powdered sulfur, concentrated sulfuric acid and battery powder, and carrying out curing reaction to obtain a cured material; the cured material is leached, and a leaching solution is obtained; mixing the leachate with the pretreated material, carrying out first adjustment treatment, and carrying out solid-liquid separation to obtain a first liquid phase; the first liquid phase is subjected to impurity removal and solid-liquid separation, an obtained second liquid phase is subjected to step-by-step extraction and reverse extraction, and valuable elements such as nickel, cobalt, manganese, lithium and zinc in the second liquid phase are recycled. The whole extraction process flow can be shortened, consumption of auxiliary materials such as rear-end acid and liquid caustic soda is reduced, and the production cost is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of hydrometallurgy, and in particular to a method for recovering valuable elements by leaching and ripening battery powder. Background Art

[0002] The main valuable metals in ternary lithium batteries are nickel, cobalt, manganese and lithium, among which nickel, cobalt and manganese are all high-valent compounds with high content. Battery powder is a powder containing nickel, cobalt, manganese, lithium and carbon powder obtained after disassembly, crushing and screening of batteries. The mass percentage of nickel, cobalt and manganese is 30-35%, and the mass percentage of lithium is 3-4%, which has a high recovery value. At present, the processing technology of battery powder is mainly a combined wet and pyro-wet leaching process. The wet process flow: disassembly, crushing, screening, leaching, extraction and other processes to obtain battery-grade nickel, cobalt and manganese sulfate solution. This process adopts reduction leaching, and the recovery rate of nickel, cobalt and manganese is relatively high. In the extraction section, the traditional extraction process has a long process flow and consumes a large amount of production auxiliary materials.

[0003] CN113174486A discloses a method for recovering valuable metals from waste lithium-ion batteries. The method first adds concentrated sulfuric acid to the battery powder for ripening and leaching, then adds water for water leaching, adds dilute sulfuric acid to the first graphite slag for acid leaching after solid-liquid separation, then adds a reducing agent for reduction leaching, then adds alkali to precipitate impurities, and finally separates the solid and liquid to obtain a second graphite slag and a second valuable metal liquid. The scheme utilizes the carbonization effect of concentrated sulfuric acid to carbonize and decompose organic matter in the battery powder, solves the problems of organic matter coating the active substances of the battery powder and bubbling and bubbling caused by organic matter during water leaching and acid leaching; the scheme reduces the roasting link, removes the organic matter in the battery powder through the ripening process, simplifies the valuable metal recovery process of waste lithium batteries, and reduces the production cost, but the leaching process is not shortened.

[0004] CN112375910A discloses a method for recycling waste power battery powder, wherein the battery materials are mixed and roasted by a reducing agent roasting process to obtain reduced battery powder, and the roasted battery powder is leached by pure water to obtain a lithium hydroxide solution and a nickel-cobalt-manganese slag, and the lithium hydroxide solution is carbonized by passing carbon dioxide to obtain lithium carbonate. The nickel-cobalt-manganese slag is leached by sulfuric acid, and the leached handover liquid is separated by extraction to obtain a nickel sulfate solution. This method uses reduction roasting and then extracts lithium by leaching, which improves the leaching rate of lithium, but nickel-cobalt-manganese is reduced to metals and leached by sulfuric acid, which will produce hydrogen and foaming, and there is a high safety risk.

[0005] CN118147461A discloses a method for treating the positive black powder leachate of a ternary lithium-ion battery. The method removes iron and aluminum by oxidation, neutralization and hydrolysis, and then extracts and replaces copper in two stages. The process is short, the purity of the obtained nickel-cobalt-manganese solution is high, and the resource value of the positive electrode material of the waste battery is improved. In addition, the P204 extractant and the BC196 extractant after manganese soap are used, and the separation coefficient is large, the processing volume is large, the acidity of the stripping acid used in the stripping is low, the acid consumption is small, and the auxiliary material consumption is small. However, in actual production, when BC196 is fully extracted, slag will be generated in the stripping stage, affecting the product quality.

[0006] Therefore, it is necessary to develop new methods to recover nickel, cobalt, manganese and lithium from the positive electrode of ternary lithium-ion batteries. Summary of the invention

[0007] In order to solve the above technical problems, the present invention provides a method for recovering valuable elements by leaching battery powder through ripening. The present invention can shorten the process flow, reduce the roasting link, and reduce energy consumption. After the ripening treatment, only pure water needs to be used for leaching at room temperature, thereby increasing the concentration of valuable elements in the first liquid phase, reducing the amount of pure water, the generation of waste water and the use of steam, and reducing production costs. Moreover, the present invention can realize the full recovery and utilization of valuable elements such as nickel, cobalt, manganese, zinc and lithium, and has a high resource utilization rate.

[0008] To achieve this object, the present invention adopts the following technical solutions:

[0009] The present invention provides a method for recovering valuable elements by leaching battery powder through ripening, the method comprising:

[0010] (1) Sulfur powder, concentrated sulfuric acid and battery powder are mixed and subjected to a aging reaction to obtain an aging material; and the aging material is leached to obtain a leachate.

[0011] (2) The leachate in step (1) is subjected to a first adjustment treatment and solid-liquid separation to obtain a first liquid phase; the first liquid phase is subjected to impurity removal and solid-liquid separation 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 by the first extraction is subjected to a first stripping to obtain a first stripping solution containing nickel, copper and zinc.

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

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

[0015] There is no order of precedence between step (4) and step (5).

[0016] The method for recovering valuable elements by aging and leaching battery powder provided by the present invention can make comprehensive use of battery powder, shorten the leaching process, reduce the consumption of auxiliary materials, and improve the industrial production capacity of the process. First, the aging process is adopted to carbonize the organic matter in the battery powder, which will not affect the later leaching, and water leaching is adopted, which does not require heating and reduces energy consumption; then, water can be directly used for leaching, and slag washing water can be used as leaching solvent, so as to realize the recycling of process wastewater, without wastewater output, and can increase the amount of washing water and reduce the metal loss rate in carbon slag.

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

[0018] Preferably, the sum of the mass percentages 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, and other values ​​not listed within the range are also applicable.

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

[0020] Preferably, the mass fraction of the concentrated sulfuric acid is ≥93wt%, for example, it can be 93wt%, 93.7wt%, 94.4wt%, 95wt%, 95.7wt%, 96.4wt%, 97wt%, 97.7wt%, 98.4wt% or 99wt%, etc., but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0021] Preferably, the temperature of the aging reaction in step (1) is 90-140°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, and other values ​​not listed within the range are also applicable.

[0022] Preferably, the aging reaction time is 5 to 20 hours, for example, it can be 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, and other unlisted values ​​within the range are also applicable.

[0023] Preferably, the mass ratio of the battery powder to the 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.

[0024] Preferably, the mass ratio of the concentrated sulfuric acid to the 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 leaching solvent 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, and other unlisted values ​​within the range are also applicable.

[0027] Preferably, the leaching temperature is 10-30°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, and other unlisted values ​​within the range are also applicable.

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

[0029] Wherein, Ni: 40-60g / L, for example, it can be 40g / L, 43g / L, 45g / L, 47g / L, 49g / L, 52g / L, 54g / L, 56g / L, 58g / L or 60g / L, but it is not limited to the listed values, and other values ​​not listed in this range are also applicable. Co: 20-30g / L, for example, it can be 20g / L, 22g / L, 23g / L, 24g / L, 25g / L, 26g / L, 27g / L, 28g / L, 29g / L or 30g / L, but it is not limited to the listed values, and other values ​​not listed in this range are also applicable. Unlisted values ​​are also applicable, Mn: 15-25 g / L, for example, it can be 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, but it is not limited to the listed values, and other unlisted values ​​within the range are also applicable, Li: 10-16 g / L, for example, it can be 10 g / L, 11 g / L, 12 g / L, 13 g / L, 14 g / L, 15 g / L or 16 g / L, but it is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[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, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

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

[0032] Preferably, the first conditioning treatment in step (2) comprises: mixing the leaching solution and the calcined battery powder to neutralize the residual acid.

[0033] In the first conditioning process of the present invention, the calcined battery powder is added to the leaching solution to neutralize the excess residual acid and oxidize the divalent iron. After filter pressing, the slag is mixed with the aging process section for use.

[0034] Preferably, the calcined battery powder is obtained by pre-treating battery powder by calcination.

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

[0037] Preferably, the amount of battery powder added after calcination in the first adjustment treatment is 1.1 to 1.2 times the theoretical consumption 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, etc., but is not limited to the listed values, and other values ​​not listed in this range are also applicable.

[0038] The battery powder after roasting contains oxides of nickel, cobalt, copper, zinc and the like, which can react with residual acid to form substances such as nickel salt, cobalt salt, copper salt or zinc salt and the like.

[0039] Preferably, the time of the first adjustment treatment 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, and other unlisted values ​​within the range are also applicable.

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

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

[0042] In the present invention, hydrogen peroxide and manganese carbonate are added to the leachate for adjustment to remove impurities such as iron and aluminum. After filter pressing, the iron-aluminum slag is slurried and washed with low acid, so that iron and aluminum can be removed at room temperature and energy consumption can be reduced. The slurry washing water is used as pure water as the leaching water for the slaking material, which reduces the introduction of water into the system, improves the metal transfer concentration, can increase the amount of washing water, and reduce the metal loss rate in the slag.

[0043] Preferably, the oxidant comprises hydrogen peroxide.

[0044] Preferably, the base comprises manganese carbonate.

[0045] Preferably, the pH value in the impurity removal 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, but is not limited to the listed values, and other values ​​not listed in the range are also applicable.

[0046] Preferably, the solid phase obtained by solid-liquid separation after impurity removal is slurried and washed.

[0047] Preferably, the endpoint pH of the slurry washing is 2-4, for example, 2, 2.3, 2.5, 2.7, 2.9, 3.2, 3.4, 3.6, 3.8 or 4, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

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

[0049] Preferably, the co-extractant comprises any one of pyridinium ester, β-diketone, diisobutyl ketone, 4,5-dimethylimidazole or 1,2-dialkylimidazole, or a combination of at least two thereof, wherein typical but non-limiting combinations are a combination of pyridinium ester and β-diketone, a combination of diisobutyl ketone and β-diketone, a combination of pyridinium ester and diisobutyl ketone, a combination of 4,5-dimethylimidazole and β-diketone, and a combination of 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, 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, and other values ​​not listed within the range are also applicable.

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

[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 the range are also applicable.

[0054] Preferably, the mass percentage of the co-extraction agent 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%, etc., but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0055] The present invention further preferably has a mass percentage content of the synergistic extractant in the first extraction system within the above range, which can reduce impurities entrained in the nickel-copper-zinc first stripping solution when a smaller amount of extractant is 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, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0057] Preferably, the first stripping adopts a sulfuric acid solution.

[0058] Preferably, the concentration of the sulfuric acid solution in the first stripping is 2 to 5 mol / L, for example, 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, and other values ​​not listed within the range are equally applicable.

[0059] Preferably, a first washing is further included between the first extraction and the first stripping.

[0060] Preferably, the wash acid of the first wash comprises a sulfuric acid solution.

[0061] Preferably, the volume ratio of the first extraction system to the washing acid in the first washing 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, and other unlisted values ​​within the range are also applicable.

[0062] Preferably, the acid concentration of the first washing is 0.5-0.8 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, and other values ​​not listed within the range are also applicable.

[0063] Preferably, the first stripping further comprises a first stripping and a first clarification performed in sequence after the first stripping.

[0064] Wherein anti-iron refers to the stripping of the iron ions in the extraction system to better restore the original performance of the extraction system. In the extraction process, due to the presence of oil phase and water phase at the same time, emulsification is easily produced, so the extraction system after anti-iron is clarified and treated, which can effectively prevent emulsification, and the extraction performance of the extraction system is restored. Anti-iron and clarification are steps after stripping of the present invention, which belong to the common means in the art, and there is no special restriction on the specific use of feed liquid, composition and ratio with the extraction system, etc., and can be adjusted according to actual conditions.

[0065] Exemplarily, the first extraction level is 6-8, the first washing level is 4-6, the first stripping level is 4-7, the first anti-iron level is 2-3, the first clarification level is 2-3, and the saponification level is one. Liquid alkali (25wt%~35wt%) is used for saponification, and the saponification rate is controlled at 40%-50%. The mass percentage of tung oil-based carboxylic acid compounds in the first extraction system is 20wt%~25wt%, the mass percentage of the co-extractant is 5wt%~10wt%, and the rest is sulfonated kerosene. The volume ratio of the extraction system of the first extraction and the second liquid phase is (3~6):1, the volume ratio of the first extraction system and the washing acid during the first washing process is 20~60:1, the washing acid concentration is 0.5-0.8mol / L, the acid concentration during the first stripping process is 2~5mol / L, and the acid of the first washing and the first stripping is sulfuric acid.

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

[0067] Preferably, the resin copper removal comprises: removing copper from the first stripping solution with a copper removal resin to obtain a copper-removed solution, and analyzing the copper-removed resin with an analytical acid to obtain a copper-containing analytical solution.

[0068] Preferably, the analytical acid is sulfuric acid.

[0069] Preferably, the concentration of the analytical acid is 1-2 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, and other values ​​not listed within the range are also applicable.

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

[0071] The present invention preferably further uses manganese powder for displacement copper removal to obtain sponge copper, and the copper removal waste liquid obtained enters the second liquid phase to recover valuable metals, and the purity of the sponge copper reaches more than 98%.

[0072] Preferably, the amount of manganese powder added in the manganese powder replacement copper removal is 0.9 to 1 times the molar content of copper in the copper-containing analytical 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, and other unlisted values ​​within this range are equally applicable.

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

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

[0075] Preferably, the second extraction system comprises an organic phosphoric acid compound and solvent oil.

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

[0077] Compared with P204, the use of P507 for zinc removal can effectively reduce the nickel carried over by P204 during zinc extraction and reduce the amount of acid used for washing.

[0078] Preferably, the mass percentage of the organophosphoric acid 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%, etc., but is not limited to the listed values, and 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 number is 6 to 8, 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, and other unlisted values ​​within the range are also applicable.

[0083] Preferably, the second stripping uses a sulfuric acid solution.

[0084] Preferably, the concentration of the sulfuric acid solution in the second stripping is 3 to 5 mol / L, for example, 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, and other values ​​not listed within the range are also applicable.

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

[0086] Preferably, the wash acid of the second wash comprises a sulfuric acid solution.

[0087] Preferably, the volume ratio of the second extraction system to the washing acid in the second washing 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, and other unlisted values ​​within the range are also applicable.

[0088] Preferably, the acid concentration of the second washing is 0.3-0.5 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, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0089] Specifically, the second extraction process adopts saponification-free zinc extraction, the second extraction level is 6-8, the second washing level is 4-6, the second stripping level is 3-7, the second clarification level is 2-3, the volume ratio of the second extraction system to the copper removal solution is 0.8-1.2:1, the concentration of the washing acid in the second washing is 0.3-0.5 mol / L, the volume ratio of the second extraction system to the washing acid solution in the second washing is 20-60:1, the acid concentration of the second stripping is 3-5 mol / L, the acid in the second washing and the second stripping is sulfuric acid, the second raffinate is obtained after zinc removal, and the stripping solution obtained by the second stripping is a high-purity zinc sulfate solution.

[0090] In addition, the high-purity zinc sulfate solution in the present invention is prepared into an electrolytic zinc product by an electrolytic process, and a zinc ingot is obtained after a melting treatment.

[0091] Preferably, the third extraction system of the third extraction in step (5) comprises an organic phosphoric acid compound and solvent oil.

[0092] The specific process is: use the third extraction system to extract cobalt, manganese, calcium and magnesium from the first raffinate, control the pH of the raffinate at 6-7, extract cobalt, manganese, calcium and magnesium, wash the calcium and magnesium in the washing section, and treat the washing water separately.

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

[0094] Preferably, the mass percentage of the organophosphoric acid 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, and other unlisted values ​​within the 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, and other unlisted values ​​within the range are also applicable.

[0096] Preferably, the third extraction has 6 to 8 stages, for example, 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, 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, and other unlisted values ​​within the range are also applicable.

[0099] Preferably, the third stripping adopts a sulfuric acid solution.

[0100] Preferably, the concentration of the sulfuric acid solution for the third stripping is 2 to 3 mol / L, for example, 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, and other values ​​not listed within the range are also applicable.

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

[0102] Preferably, the washing acid of the third washing comprises 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, and other unlisted values ​​within the range are also applicable.

[0104] Preferably, the concentration of the washing acid in the third washing is 0.3-0.6 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, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

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

[0106] In the present invention, MVR evaporation (Mechanical Vapor Recompression) refers to mechanical vapor recompression evaporation, that is, 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 a cobalt removal treatment using a cobalt removal resin and the cobalt removal resin is analyzed to obtain a cobalt sulfate analysis solution.

[0109] The cobalt-containing manganese calcium magnesium chloride solution of the present invention is adsorbed by a cobalt removal resin to remove cobalt, and the obtained cobalt sulfate analysis solution is returned to the third extraction.

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

[0111] Preferably, the calcium-magnesium solution is adjusted to a pH value of 13 or above by adding liquid alkali to precipitate calcium and magnesium, and a mixed system is obtained to obtain calcium-magnesium hydroxide slag and a magnesium-removed liquid after solid-liquid separation. The pH value of 13 or above can be, for example, 13.0, 13.1, 13.2, 13.3, 13.5, 13.8 or 14.0, etc.

[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 stripping.

[0114] Preferably, after the third stripping, a third stripping and a fourth clarification are sequentially performed.

[0115] Specifically, the overall process of the third extraction is: third extraction 6-8 levels, third washing 6-8 levels, third clarification 1 level, third stripping 4-6 levels, third anti-iron 2-3 levels, and fourth clarification 2-3 levels. The third extraction system uses liquid alkali (25wt%~35wt%) for saponification, and the saponification rate is controlled at 40%~45%. The volume ratio of the third extraction system and the first raffinate during the third extraction process is 4~6:1, the washing acid in the third washing is hydrochloric acid, and the hydrochloric acid concentration is 0.3~0.6mol / L. The volume ratio of the third extraction system and the washing acid during the third washing process is 40~60:1, and the stripping acid of the third stripping is sulfuric acid, and the sulfuric acid concentration is 2~3mol / L. Cobalt manganese sulfate solution (third stripping solution), calcium magnesium chloride solution (third washing solution) and lithium sodium solution (raffinate obtained from the third extraction) are obtained, and the lithium sodium solution is prepared by MVR evaporation and carbonization process to prepare lithium carbonate.

[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 by aging provided by the present invention uses sulfur powder to carry out reduction aging reaction on battery powder, and nickel, cobalt, manganese and lithium can be completely leached out through aging reaction. Compared with the prior art, the process flow is shortened, the roasting link is reduced, and the energy consumption is reduced. After the aging reaction, only pure water needs to be used 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, and reduces production costs.

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

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

[0120] (4) The method for recovering valuable elements by leaching battery powder after aging provided by the present invention adopts tung oil-based carboxylic acid (TFCA, C 18 H 30 O2) + diisobutyl ketone synergistic extraction system preferentially and selectively extracts nickel from the second liquid phase. Combined with the saponification-free extraction and zinc removal process, nickel sulfate solution can be obtained at one time, 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 by aging provided by the present invention preferably uses P507 extraction to separate zinc from the first stripping solution containing nickel, copper and zinc to prepare high-purity zinc sulfate, and then electrolyzes the zinc sulfate solution to prepare an electrolytic zinc product, thereby realizing the comprehensive utilization of zinc resources.

[0122] (6) The method for recovering valuable elements by leaching battery powder by ripening provided by the present invention separates calcium and magnesium from the first raffinate, reduces the influence of calcium and magnesium on the equipment during lithium evaporation and extraction, and reduces 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 produced by the cobalt removal treatment to obtain magnesium hydroxide slag and magnesium-removed liquid, and returns the cobalt sulfate analysis liquid of the cobalt removal resin to the third extraction, and basically all valuable metals such as nickel, cobalt, manganese, and lithium are recovered.

[0123] (7) The method for recovering valuable elements by leaching and ripening battery powder provided by the present invention shortens the overall extraction process flow: preferentially extracting nickel + extracting cobalt and manganese, shortening the extraction process flow, reducing the consumption of auxiliary materials such as acid and liquid alkali at the back end, and reducing production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0124] Figure 1 A schematic diagram of the leaching process in the method for recovering valuable elements by leaching battery powder through ripening provided in Example 1 of the present invention.

[0125] Figure 2 A schematic diagram of the extraction process in the method for recovering valuable elements by leaching battery powder through ripening provided in Example 1 of the present invention. DETAILED DESCRIPTION

[0126] For the convenience of understanding the present invention, the present invention lists the following embodiments. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0127] It should be understood that the terms "first", "second", etc. are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly indicate the number of technical features indicated. Thus, a feature defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0128] Example 1

[0129] This embodiment provides a method for recovering valuable elements by leaching through the aging reaction of battery powder. Figure 1-2 , the method comprises 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 react for 10 hours to obtain a matured material.

[0131] Add water to the matured material to adjust the slurry to a liquid-solid ratio of 3 ml:1 g, stir and leach for 1 hour at room temperature (25°C), filter press to obtain a leachate (nickel cobalt manganese lithium sulfate leachate) and a first leaching residue (mainly carbon residue); the first leaching residue is slurried and washed to obtain carbon residue and residue washing water, and the residue washing water is returned to the leachate.

[0132] (2) The mixed leachate and calcined battery powder (calcination temperature 450°C, 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 filter press to obtain a first liquid phase (i.e., filter press) and battery powder residue, manganese carbonate and hydrogen peroxide are added to the obtained first liquid phase to adjust the iron and aluminum to remove impurities, the pH is controlled between 5.0 and 6.5, the reaction time is 1h, the reaction material is filtered to obtain a second liquid phase and filter press residue, the filter press residue is slurried and washed, the end point pH of the slurry washing is 2.5, and then iron and aluminum slag and slag washing water are obtained, and the slag washing water is circulated to the leachate of step (1).

[0133] (3) The second liquid phase uses the first extraction system to extract nickel, zinc, copper and cobalt, wherein the mass percentage of TFCA in the first extraction system is 20wt%, the mass percentage of diisobutyl ketone is 10wt%, and the rest 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 uses 30wt% of liquid alkali for primary saponification treatment, the saponification rate is 40%, and 8 levels of first extraction are performed; then a first washing is performed, the volume ratio of the first extraction system and the washing acid of the first washing is 20:1, the washing acid is 0.5mol / L sulfuric acid, and the number of the first washing is 6; then a first stripping is performed, the stripping acid of the first stripping is 2mol / L sulfuric acid, and the number of the first stripping is 7; then 2 levels of first iron removal and 3 levels of first clarification are performed; wherein the first extraction obtains a first raffinate, and the first stripping obtains a first stripping solution containing nickel, copper and zinc.

[0134] (4) The first stripping solution containing nickel, copper and zinc is subjected to copper removal by resin, wherein the resin is a copper removal resin (specific model is LSC-495). After the first stripping solution containing nickel, copper and zinc passes through the resin, the copper content is reduced to below 1 mg / L. The stripping solution is subjected to analysis by 1.68 mol / L sulfuric acid to obtain a copper-containing analysis solution. The copper-containing analysis solution is subjected to copper removal by displacement by manganese powder, wherein the amount of manganese powder added is 0.95 times the molar content of copper in the copper-containing analysis solution to obtain sponge copper. The copper removal waste liquid after copper removal by displacement by manganese powder is blended into the second liquid phase for recovering manganese.

[0135] The liquid phase after the copper removal by the resin is a copper removal liquid, and the copper removal liquid enters the extraction system for zinc removal, and the zinc removal is carried out by a second extraction system, the mass percentage of P507 in the second extraction system is 8wt%, and the rest is sulfonated kerosene, the second extraction system is not saponified before the second extraction, the second extraction has 8 levels, and the volume ratio of the second extraction system to the copper removal liquid is 1.0:1; then a second washing is carried out, the volume ratio of the second extraction system to the washing acid in the second washing is 30:1, the washing acid is 0.4mol / L sulfuric acid, and the second washing has 5 levels; then a second stripping is carried out, the stripping acid of the second stripping is 4mol / L sulfuric acid, and the second stripping has 5 levels; and then a 3-level second clarification is carried out; wherein, a nickel sulfate solution is obtained after the second extraction, a zinc sulfate solution is obtained after the second stripping, and electrolytic zinc is obtained after the zinc sulfate solution is electrolyzed.

[0136] (5) The first raffinate is extracted with calcium, magnesium, cobalt and manganese by a third extraction system, wherein the mass percentage of C272 in the third extraction system is 22wt%, the mass percentage of TBP (tributyl phosphate) is 3wt%, and the rest 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 number of stages of the third extraction is 7. A lithium-sodium solution (third raffinate) is obtained in the third extraction, and lithium carbonate is prepared from the lithium-sodium solution by MVR evaporation and carbonization process.

[0137] Then, a third washing is performed, and the washing acid of the third washing is a 0.4 mol / L hydrochloric acid solution; in the third washing, the volume ratio of the third extraction system to the washing acid is 50:1, and the third washing produces a cobalt-manganese calcium-magnesium chloride solution, and the cobalt-manganese calcium-magnesium chloride solution is subjected to a cobalt removal treatment by a cobalt removal resin and the cobalt removal resin is analyzed to obtain a cobalt sulfate analysis solution; the cobalt removal treatment also produces a calcium-magnesium solution; the calcium-magnesium solution is added with liquid alkali to adjust the pH to 13.5 to precipitate calcium and magnesium, and a mixed system is obtained, which is filtered and then subjected to pressure filtration 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 third clarification stage 1, the third stripping stage 5, the third stripping stage 3, and the fourth clarification stage 2 are carried out in sequence, wherein the third stripping adopts a sulfuric acid solution, the concentration of the sulfuric acid solution of the third stripping is 2.5 mol / L, and the third stripping obtains a cobalt manganese sulfate solution.

[0139] There is no order of precedence between step (4) and step (5).

[0140] The contents of the elements in the second liquid phase in this embodiment are 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 contents of various elements in the first raffinate in this embodiment are shown in Table 2.

[0144] Table 2

[0145]

[0146] The composition of the nickel-copper-zinc first stripping 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 1.3mg / L 0.4mg / L 0.2mg / 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 1.25mg / L 0.3mg / L 0.2mg / L 1mg / L 0.1mg / 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 0.2mg / L 4.9mg / L 1.5mg / L

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

[0156] Table 6

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

[0158] The composition of calcium magnesium chloride solution in the present 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 compositions of nickel, cobalt, manganese and lithium in the first leaching residue in this embodiment are 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 compositions of nickel, cobalt, manganese and lithium in the iron-aluminum slag in this embodiment are 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 aging reaction of battery powder, the method comprising the following steps:

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

[0170] The battery powder, sulfur powder and concentrated sulfuric acid were stirred and mixed evenly, and heated to 110° C. for aging reaction for 10 hours to obtain an aged material.

[0171] Add water to the matured material to adjust the slurry to a liquid-solid ratio of 3 ml:1 g, stir and leach for 1 hour at room temperature (25°C), filter, and obtain a leachate (nickel cobalt manganese lithium sulfate leachate) and a first leaching residue (mainly carbon residue); the first leaching residue is slurried and washed to obtain carbon residue and residue washing water, and the residue washing water is returned to the leachate.

[0172] (2) The mixed leachate and calcined battery powder (calcination temperature 450°C, 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 filter press to obtain a first liquid phase, the first liquid phase, i.e., the filter press, is added with manganese carbonate and hydrogen peroxide to adjust the iron and aluminum to remove impurities, the pH is controlled between 5.0 and 6.0, the reaction time is 1h, the reaction material is filtered to obtain a second liquid phase and filter press residue, the filter press residue is slurried and washed, the end point pH of the slurry washing is 4.0, and then iron and aluminum slag and slag washing water are obtained, and the slag washing water is circulated to the leachate of step (1).

[0173] (3) The second liquid phase uses the first extraction system to extract nickel, zinc, copper and cobalt, wherein the mass percentage of TFCA in the first extraction system is 25wt%, the mass percentage of diisobutyl ketone is 5wt%, and the rest 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 uses 35wt% of liquid alkali for primary saponification treatment, the saponification rate is 50%, and 8 levels of first extraction are performed; then a first washing is performed, in which the volume ratio of the first extraction system and the washing acid is 60:1, the washing acid is 0.8mol / L sulfuric acid, and the number of the first washing is 6; then a first stripping is performed, the stripping acid of the first stripping is 5mol / L sulfuric acid, and the number of the first stripping is 7; then 2 levels of first iron removal and 3 levels of first clarification are performed; wherein the first extraction obtains a first raffinate, and the first stripping obtains a first stripping solution containing nickel, copper and zinc.

[0174] (4) The first stripping solution containing nickel, copper and zinc is subjected to copper removal by resin, wherein the resin is a copper removal resin (specific model is LSC-495). After the first stripping solution containing nickel, copper and zinc passes through the resin, the copper content is reduced to below 1 mg / L. The stripping solution is subjected to analysis by 2 mol / L sulfuric acid to obtain a copper-containing analysis solution. The copper-containing analysis solution is subjected to copper removal by displacement by manganese powder, wherein the amount of manganese powder added is 0.9 times the molar content of copper in the copper-containing analysis solution to obtain sponge copper. The copper removal waste liquid after copper removal by displacement by manganese powder is blended into the second liquid phase for recovering manganese.

[0175] The liquid phase after copper removal by resin is copper removal liquid, the copper removal liquid enters the extraction system for zinc removal, the second extraction system is used for zinc removal, the mass percentage of P507 in the second extraction system is 10wt%, and the rest is sulfonated kerosene, the second extraction system is not saponified before the second extraction, the second extraction stage is 7, and the volume ratio of the second extraction system to the copper removal liquid is 1.2:1; then a second washing is performed, the volume ratio of the second extraction system to the washing acid in the second washing is 20:1, the washing acid is 0.5mol / L sulfuric acid, and the second washing stage is 6; then a second stripping is performed, the stripping acid of the second stripping is 4mol / L sulfuric acid, and the second stripping stage is 7; and then a second clarification is performed for 2 levels; wherein, a nickel sulfate solution is obtained after the second extraction, a zinc sulfate solution is obtained after the second stripping, and the zinc sulfate solution is electrolyzed to obtain electrolytic zinc.

[0176] (5) The first raffinate is extracted with calcium, magnesium, cobalt and manganese by a third extraction system, wherein the mass percentage of C272 in the third extraction system is 20wt%, the mass percentage of TBP (tributyl phosphate) is 3wt%, and the rest 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 number of stages of the third extraction is 6. A lithium-sodium solution (third raffinate) is obtained in the third extraction, and lithium carbonate is prepared from the lithium-sodium solution by MVR evaporation and carbonization process.

[0177] Then, a third washing is performed, in which the washing acid is a 0.3 mol / L hydrochloric acid solution; in the third washing, the volume ratio of the third extraction system to the washing acid is 40:1, and the third washing produces a cobalt-manganese-containing calcium-magnesium chloride solution, which is subjected to a cobalt-removing resin to remove cobalt and the cobalt-removing resin is analyzed to obtain a cobalt sulfate analysis solution; the cobalt-removing treatment also produces a calcium-magnesium solution; the calcium-magnesium solution is adjusted to a pH of 13.2 by adding liquid alkali to precipitate calcium and magnesium, and a mixed system is obtained by filter pressing 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 third clarification stage 1, the third stripping stage 4, the third stripping stage 2, and the fourth clarification stage 3 are carried out in sequence, wherein the third stripping adopts a sulfuric acid solution, the concentration of the sulfuric acid solution of the third stripping is 2 mol / L, and the third stripping obtains a cobalt manganese sulfate solution.

[0179] There is no order of precedence between step (4) and step (5).

[0180] Example 3

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

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

[0183] The battery powder, sulfur powder and concentrated sulfuric acid were stirred and mixed evenly, and heated to 90° C. for aging reaction for 20 hours to obtain an aged material.

[0184] Add water to the matured material to adjust the slurry to a liquid-solid ratio of 5 ml:1 g, stir and leach for 1 hour at room temperature (25°C), filter, and obtain a leachate (nickel cobalt manganese lithium sulfate leachate) and a first leaching residue (mainly carbon residue); the first leaching residue is slurried and washed to obtain carbon residue and residue washing water, and the residue washing water is returned to the leachate.

[0185] (2) The mixed leachate and the calcined battery powder (calcination temperature 500°C, 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 a first conditioning treatment for 1h, and filter press to obtain a first liquid phase, the first liquid phase, i.e., the filter press, is adjusted to remove iron and aluminum by adding manganese carbonate and hydrogen peroxide, the pH is controlled between 5.5 and 6.5, the reaction time is 1.5h, the reaction material is filtered to obtain a second liquid phase and filter press residue, the filter press residue is slurried and washed, the end point pH of the slurry washing is 2.3, and then iron and aluminum slag and slag washing water are obtained, and the slag washing water is circulated to the leachate of step (1).

[0186] (3) The second liquid phase uses the first extraction system to extract nickel, zinc, copper and cobalt, wherein the mass percentage of TFCA in the first extraction system is 22wt%, the mass percentage of diisobutyl ketone is 8wt%, and the rest 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 32wt% of liquid alkali for primary saponification treatment, the saponification rate is 45%, and 8 levels of first extraction are performed; then a first washing is performed, in which the volume ratio of the first extraction system and the washing acid is 30:1, the washing acid is 0.6mol / L sulfuric acid, and the number of the first washing is 6; then a first stripping is performed, the stripping acid of the first stripping is 4mol / L sulfuric acid, and the number of the first stripping is 7; then 2 levels of first iron removal and 3 levels of first clarification are performed; wherein the first extraction obtains a first raffinate, and the first stripping obtains a first stripping solution containing nickel, copper and zinc.

[0187] (4) The first stripping solution containing nickel, copper and zinc is subjected to copper removal by resin, wherein the resin is a copper removal resin (specific model is LSC-495). After the first stripping solution containing nickel, copper and zinc passes through the resin, the copper content is reduced to below 1 mg / L. 1 mol / L sulfuric acid is used for analysis to obtain a copper-containing analysis solution. Manganese powder is used for displacement copper removal by the copper-containing analysis solution. The amount of manganese powder added is 1 times the molar content of copper in the copper-containing analysis solution to obtain sponge copper. The copper removal waste liquid after copper removal by manganese powder is blended into the second liquid phase for recovering manganese.

[0188] The liquid phase after copper removal by resin is copper removal liquid, the copper removal liquid enters the extraction system for zinc removal, the second extraction system is used for zinc removal, the mass percentage of P507 in the second extraction system is 3wt%, and the rest is sulfonated kerosene, the second extraction system is not saponified before the second extraction, the second extraction stage is 6, and the volume ratio of the second extraction system to the copper removal liquid is 0.8:1; then a second washing is performed, the volume ratio of the second extraction system to the washing acid in the second washing is 60:1, the washing acid is 0.4mol / L sulfuric acid, and the second washing stage is 4; then a second stripping is performed, the stripping acid of the second stripping is 3mol / L sulfuric acid, and the second stripping stage is 6; and then a 3-stage second clarification is performed; wherein, a nickel sulfate solution is obtained after the second extraction, a zinc sulfate solution is obtained after the second stripping, and electrolytic zinc is obtained after the zinc sulfate solution is electrolyzed.

[0189] (5) The first raffinate is extracted with calcium, magnesium, cobalt and manganese using a third extraction system, wherein the mass percentage of C272 in the third extraction system is 21wt%, the mass percentage of TBP (tributyl phosphate) is 4wt%, and the rest 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 number of stages of the third extraction is 8. A lithium-sodium solution (third raffinate) is obtained in the third extraction, and lithium carbonate is prepared from the lithium-sodium solution through MVR evaporation and carbonization process.

[0190] Then, a third washing is performed, in which the washing acid is a 0.6 mol / L hydrochloric acid solution; in the third washing, the volume ratio of the third extraction system to the washing acid is 60:1, and the third washing produces a cobalt-manganese-containing calcium-magnesium chloride solution, which is subjected to a cobalt-removing resin to remove cobalt and the cobalt-removing resin is analyzed to obtain a cobalt sulfate analysis solution; the cobalt-removing treatment also produces a calcium-magnesium solution; the calcium-magnesium solution is adjusted to a pH of 14 by adding liquid alkali to precipitate calcium and magnesium, and a mixed system is obtained, which is filtered to obtain calcium-magnesium hydroxide slag and a magnesium-removed liquid; the magnesium-removed liquid is used as an alkali for saponification.

[0191] Then, the third clarification stage 1, the third stripping stage 6, the third stripping stage 3, and the fourth clarification stage 2 are carried out in sequence, wherein the third stripping adopts a sulfuric acid solution, the concentration of the sulfuric acid solution of the third stripping is 3 mol / L, and the third stripping obtains a cobalt manganese sulfate solution.

[0192] There is no order of precedence between step (4) and step (5).

[0193] Example 4

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

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

[0196] The battery powder, sulfur powder and concentrated sulfuric acid were stirred and mixed evenly, and heated to 140° C. for aging reaction for 5 hours to obtain an aged material.

[0197] Add water to the matured material to adjust the slurry to a liquid-solid ratio of 2 ml: 1 g, stir and leach for 3 hours at 10°C, filter, and obtain a leachate (nickel cobalt manganese lithium sulfate leachate) and a first leaching residue (mainly carbon residue); the first leaching residue is slurried and washed to obtain carbon residue and slag washing water, and the slag washing water is returned to the leachate.

[0198] (2) The mixed leachate and the calcined battery powder (calcination temperature 400°C, 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 a first conditioning treatment for 2h, and filter press to obtain a first liquid phase, the first liquid phase, i.e., the filter press, is adjusted to remove iron and aluminum by adding manganese carbonate and hydrogen peroxide, the pH is controlled between 5.5 and 6.0, the reaction time is 1.2h, the reaction material is filtered to obtain a second liquid phase and filter press residue, the filter press residue is slurried and washed, the end point pH of the slurry washing is 3.5, and then iron and aluminum slag and slag washing water are obtained, and the slag washing water is circulated to the leachate of step (1).

[0199] (3) The second liquid phase uses the first extraction system to extract nickel, zinc, copper and cobalt, wherein the mass percentage of TFCA in the first extraction system is 21wt%, the mass percentage of diisobutyl ketone is 7.5wt%, and the rest 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 25wt% of liquid alkali for primary saponification treatment, the saponification rate is 40%, and 8 levels of first extraction are performed; then a first washing is performed, in which the volume ratio of the first extraction system and the washing acid is 50:1, the washing acid is 0.7mol / L sulfuric acid, and the number of the first washing is 6; then a first stripping is performed, the stripping acid of the first stripping is 5mol / L sulfuric acid, and the number of the first stripping is 7; then 2 levels of first iron removal and 3 levels of first clarification are performed; wherein the first extraction obtains a first raffinate, and the first stripping obtains a first stripping solution containing nickel, copper and zinc.

[0200] (4) The first stripping solution containing nickel, copper and zinc is subjected to copper removal by resin, wherein the resin is a copper removal resin (specific model is LSC-495). After the first stripping solution containing nickel, copper and zinc passes through the resin, the copper content is reduced to below 1 mg / L. The stripping solution is subjected to analysis by 1.5 mol / L sulfuric acid to obtain a copper-containing analysis solution. The copper-containing analysis solution is subjected to copper removal by displacement by manganese powder, wherein the amount of manganese powder added is 0.92 times the molar content of copper in the copper-containing analysis solution to obtain sponge copper. The copper removal waste liquid after copper removal by displacement by manganese powder is blended into the second liquid phase for recovering manganese.

[0201] The liquid phase after copper removal by resin is copper removal liquid, the copper removal liquid enters the extraction system for zinc removal, the second extraction system is used for zinc removal, the mass percentage of P507 in the second extraction system is 5wt%, and the rest is sulfonated kerosene, the second extraction system is not saponified before the second extraction, the second extraction stage is 6, and the volume ratio of the second extraction system to the copper removal liquid is 1.0:1; then a second washing is performed, the volume ratio of the second extraction system to the washing acid in the second washing is 40:1, the washing acid is 0.3mol / L sulfuric acid, and the second washing stage is 6; then a second stripping is performed, the stripping acid of the second stripping is 3mol / L sulfuric acid, and the second stripping stage is 3; and then a second clarification is performed for 2 stages; wherein a nickel sulfate solution is obtained after the second extraction, a zinc sulfate solution is obtained after the second stripping, and electrolytic zinc is obtained after the zinc sulfate solution is electrolyzed.

[0202] (5) The first raffinate is extracted with calcium, magnesium, cobalt and manganese by a third extraction system, wherein the mass percentage of C272 in the third extraction system is 20wt%, the mass percentage of TBP (tributyl phosphate) is 2wt%, and the rest 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 number of stages of the third extraction is 6. A lithium-sodium solution (third raffinate) is obtained in the third extraction, and lithium carbonate is prepared from the lithium-sodium solution by MVR evaporation and carbonization process.

[0203] Then, a third washing is performed, and the washing acid of the third washing is a 0.3 mol / L hydrochloric acid solution; in the third washing, the volume ratio of the third extraction system to the washing acid is 44:1, and the third washing produces a cobalt-manganese-containing calcium-magnesium chloride solution, and the cobalt-removing resin is used to remove cobalt from the cobalt-containing calcium-magnesium chloride solution, and the cobalt-removing resin is analyzed to obtain a cobalt sulfate analysis solution; the cobalt removal treatment also produces a calcium-magnesium solution; the calcium-magnesium solution is added with liquid alkali to adjust the pH to 13.5 to precipitate calcium and magnesium, and a mixed system is obtained, which is 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 third clarification stage 1, the third stripping stage 4, the third stripping stage 2, and the fourth clarification stage 3 are carried out in sequence, wherein the third stripping adopts a sulfuric acid solution, the concentration of the sulfuric acid solution of the third stripping is 2 mol / L, and the third stripping obtains a cobalt manganese sulfate solution.

[0205] There is no order of precedence between step (4) and step (5).

[0206] Example 5

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

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

[0209] The battery powder, sulfur powder and concentrated sulfuric acid were stirred and mixed evenly, and heated to 100° C. for aging reaction for 15 hours to obtain an aged material.

[0210] Add water to the matured material to adjust the slurry to a liquid-solid ratio of 3.5 ml: 1 g, stir and leach for 2.5 hours at 30°C, filter, and obtain a leachate (nickel cobalt manganese lithium sulfate leachate) and a first leaching residue (mainly carbon residue); the first leaching residue is slurried and washed to obtain carbon residue and residue washing water, and the residue washing water is returned to the leachate.

[0211] (2) The mixed leachate and calcined battery powder (calcination temperature 420°C, 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 a first conditioning treatment for 2h, and filter press to obtain a first liquid phase, the first liquid phase, i.e., the filter press, is adjusted to remove iron and aluminum by adding manganese carbonate and hydrogen peroxide, the pH is controlled between 5.0 and 6.0, the reaction time is 1.5h, the reaction material is filtered to obtain a second liquid phase and filter press residue, the filter press residue is slurried and washed, the end point pH of the slurry washing is 3.2, and then iron and aluminum slag and slag washing water are obtained, and the slag washing water is circulated to the leachate of step (1).

[0212] (3) The second liquid phase uses the first extraction system to extract nickel, zinc, copper and cobalt, wherein the mass percentage of TFCA in the first extraction system is 21wt%, the mass percentage of diisobutyl ketone is 10wt%, and the rest 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 uses 30wt% of liquid alkali for primary saponification treatment, the saponification rate is 45%, and 8 levels of first extraction are performed; then a first washing is performed, in which the volume ratio of the first extraction system and the washing acid is 30:1, the washing acid is 0.7mol / L sulfuric acid, and the number of the first washing is 6; then a first stripping is performed, the stripping acid of the first stripping is 3.5mol / L sulfuric acid, and the number of the first stripping is 7; then 2 levels of first iron stripping and 3 levels of first clarification are performed; wherein the first extraction obtains a first raffinate, and the first stripping obtains a first stripping solution containing nickel, copper and zinc.

[0213] (4) The first stripping solution containing nickel, copper and zinc is subjected to copper removal by resin, wherein the resin is a copper removal resin (specific model is LSC-495). After the first stripping solution containing nickel, copper and zinc passes through the resin, the copper content is reduced to below 1 mg / L. The stripping solution is subjected to analysis by 1.2 mol / L sulfuric acid to obtain a copper-containing analysis solution. The copper-containing analysis solution is subjected to copper removal by displacement by manganese powder, wherein the amount of manganese powder added is 1 times the molar content of copper in the copper-containing analysis solution to obtain sponge copper. The copper removal waste liquid after copper removal by displacement by manganese powder is blended into the second liquid phase for recovering manganese.

[0214] The liquid phase after copper removal by resin is copper removal liquid, the copper removal liquid enters the extraction system for zinc removal, the second extraction system is used for zinc removal, the mass percentage of P507 in the second extraction system is 5wt%, and the rest is sulfonated kerosene, the second extraction system is not saponified before the second extraction, the second extraction stage is 7, and the volume ratio of the second extraction system to the copper removal liquid is 0.9:1; then a second washing is performed, the volume ratio of the second extraction system to the washing acid in the second washing is 60:1, the washing acid is 0.3mol / L sulfuric acid, and the second washing stage is 5; then a second stripping is performed, the stripping acid of the second stripping is 3mol / L sulfuric acid, and the second stripping stage is 6; and then a 3-stage second clarification is performed; wherein, a nickel sulfate solution is obtained after the second extraction, a zinc sulfate solution is obtained after the second stripping, and electrolytic zinc is obtained after the zinc sulfate solution is electrolyzed.

[0215] (5) The first raffinate is extracted with calcium, magnesium, cobalt and manganese using a third extraction system, wherein the mass percentage of C272 in the third extraction system is 24wt%, the mass percentage of TBP (tributyl phosphate) is 1wt%, and the rest 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 number of stages of the third extraction is 8. A lithium-sodium solution (third raffinate) is obtained in the third extraction, and lithium carbonate is prepared from the lithium-sodium solution through MVR evaporation and carbonization process.

[0216] Then, a third washing is performed, in which the washing acid is a 0.6 mol / L hydrochloric acid solution; in the third washing, the volume ratio of the third extraction system to the washing acid is 40:1, and the third washing produces a cobalt-manganese calcium-magnesium chloride solution, which is subjected to a cobalt-removing resin to remove cobalt and the cobalt-removing resin is analyzed to obtain a cobalt sulfate analysis solution; the cobalt-removing treatment also produces a calcium-magnesium solution; the calcium-magnesium solution is adjusted to a pH of 13.5 by adding liquid alkali to precipitate calcium and magnesium, and a mixed system is obtained by filter pressing to obtain calcium-magnesium hydroxide slag and a magnesium-removed liquid; the magnesium-removed liquid is used as an alkali for saponification.

[0217] Then, the third clarification stage 1, the third stripping stage 6, the third stripping stage 2, and the fourth clarification stage 2 are carried out in sequence, wherein the third stripping adopts a sulfuric acid solution, the concentration of the sulfuric acid solution of the third stripping is 2.2 mol / L, and the third stripping obtains a cobalt manganese sulfate solution.

[0218] There is no order of precedence between step (4) and step (5).

[0219] The leaching rate data of 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 battery powder during ripening. The method is the same as that of Embodiment 1 except that the mass percentage of TFCA in the first extraction system is 15 wt %, and will not be described in detail here.

[0224] The composition of the first stripping solution containing nickel, copper and zinc 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 3.3mg / L 1.2mg / L 0.6mg / L 82mg / L 150mg / L

[0227] From the results in the above table, it can be seen that the low mass percentage of TFCA will affect the impurity content, the extractant load is low, and the impurities entrained in the first stripping solution containing nickel, copper and zinc are high.

[0228] Example 7

[0229] This embodiment provides a method for recovering valuable elements by leaching battery powder during ripening. The method is the same as that of Embodiment 1 except that the mass percentage of TFCA in the first extraction system is 28 wt %, and will not be described in detail here.

[0230] The composition of the first stripping solution containing nickel, copper and zinc 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 1.3mg / L 0.4mg / L 0.2mg / L 82mg / L 150mg / L

[0233] From the results in the above table, it can be seen that the mass percentage of TFCA is high, the extractant loading is high, and the organic impurities entrained are comparable to those in Example 1. However, the extractant content is high, the utilization rate of the extractant is low, and the initial investment cost is high.

[0234] Example 8

[0235] This embodiment provides a method for recovering valuable elements by leaching battery powder through ripening. The method is the same as that of Embodiment 1 except that P507 is replaced by P204 in the second extraction system, and thus will not be described in detail 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 20.9mg / L 0.75g / L 1.5mg / 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 is detrimental to the back-end zinc sulfate electrolysis.

[0240] Comparative Example 1

[0241] This comparative example provides a method for recovering valuable elements by leaching battery powder through ripening. The method is the same as Example 1 except that the ripening reaction is not performed, and will not be described in detail here.

[0242] This comparative example does not carry out a aging reaction, so the subsequent process is difficult to carry out and it is difficult to achieve effective recovery of the elements.

[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 Example 1 except that no sulfur powder is added in the aging reaction and only concentrated sulfuric acid is used, and no further description is given here.

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

[0246] Comparative Example 3

[0247] This comparative example provides a method for recovering valuable elements by leaching battery powder during aging. The method is the same as Example 1 except that concentrated sulfuric acid is not added in the aging reaction and only sulfur powder is used, and will not be described in detail here.

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

[0249] Comparative Example 4

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

[0251] In this comparative example, no impurity removal treatment is performed, and the subsequent first extraction process is difficult to carry out, resulting in difficulty in separating the elements.

[0252] The present invention illustrates the detailed features of the present invention through the above embodiments, 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 improvement to the present invention, equivalent replacement of the technical features selected by the present invention, addition of auxiliary technical features, 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 battery powder during ripening, characterized in that: The method comprises: (1) mixing sulfur powder, concentrated sulfuric acid and battery powder to perform a aging reaction to obtain an aging material; and leaching the aging material to obtain a leachate; (2) The leachate of step (1) is subjected to a first conditioning treatment and solid-liquid separation to obtain a first liquid phase; the first liquid phase is subjected to impurity removal and solid-liquid separation to obtain a second liquid phase; (3) subjecting the second liquid phase to a first extraction to obtain a first raffinate, and subjecting the extract obtained by the first extraction to a first stripping solution to obtain a first stripping solution containing nickel, copper and zinc; (4) the first stripping solution containing nickel, copper and zinc is subjected to copper removal and second extraction and zinc removal in sequence to obtain a second raffinate which is a nickel sulfate solution, and the second extract obtained by the second extraction and zinc removal is subjected to a second stripping to obtain a zinc sulfate solution; (5) The first raffinate is subjected to a third extraction to obtain a third raffinate which is a lithium-sodium solution, and the third extract obtained by the third extraction is subjected to a third stripping to obtain a cobalt-manganese sulfate solution; There is no order of precedence between step (4) and step (5).

2. The method according to claim 1, characterized in that The battery powder in step (1) is a ternary lithium-ion battery positive electrode powder; Preferably, the sum of the mass percentages of nickel, cobalt and manganese in the battery powder is 30wt% to 35wt%; Preferably, the sulfur powder is industrial sulfur powder, and the purity of the sulfur powder is greater than 99wt%; Preferably, the mass fraction of the concentrated sulfuric acid is ≥93wt%.

3. The method according to claim 1 or 2, characterized in that: The temperature of the aging reaction in step (1) is 90-140°C; Preferably, the aging reaction time is 5 to 20 hours; Preferably, the mass ratio of the battery powder to the sulfur powder is 15 to 32:1; Preferably, the mass ratio of the concentrated sulfuric acid to the battery powder is 0.9-1.4:

1.

4. The method according to any one of claims 1 to 3, characterized in that: The leaching solvent in step (1) is water; Preferably, the leaching time is 1 to 3 hours; Preferably, the leaching temperature is 10 to 30°C; Preferably, the metal element composition in the leaching solution includes: Ni: 40-60 g / L, Co: 20-30 g / L, Mn: 15-25 g / L, Li: 10-16 g / L; Preferably, the liquid-to-solid ratio of the leaching is 2-5 ml:1 g; Preferably, carbon residue is separated during the leaching process.

5. The method according to any one of claims 1 to 4, characterized in that: The first conditioning treatment in step (2) includes: mixing the leaching solution and the calcined battery powder to neutralize the residual acid; Preferably, the calcined battery powder is obtained by pre-treating battery powder by calcination; Preferably, the temperature of the calcination pretreatment is 400-500°C; Preferably, the calcination pretreatment time is 1 to 6 hours; Preferably, the amount of the calcined battery powder added in the first conditioning treatment is 1.1 to 1.2 times the theoretical consumption required to convert the residual acid into salt; Preferably, the first conditioning treatment lasts for 1 to 2 hours; Preferably, the solid-liquid separation after the first conditioning treatment in step (2) is filter press.

6. The method according to any one of claims 1 to 5, characterized in that: The impurity removal in step (2) includes mixing an oxidant, a base and a first liquid phase to remove iron and aluminum; Preferably, the oxidant comprises hydrogen peroxide; Preferably, the base comprises manganese carbonate; Preferably, the pH value during the impurity removal is 5 to 6.5; Preferably, the solid phase obtained by solid-liquid separation after impurity removal is slurried and washed; Preferably, the endpoint pH of the slurry washing is 2-4.

7. The method according to any one of claims 1 to 6, characterized in that: In step (3), the first extraction system in the first extraction comprises tung oil-based carboxylic acid, a co-extraction agent and an organic solvent; Preferably, the co-extractant includes any one or a combination of at least two of pyridinium ester, β-diketone, diisobutyl ketone, 4,5-dimethylimidazole or 1,2-dialkylimidazole; Preferably, the organic solvent in the first extraction system is sulfonated kerosene; Preferably, the mass percentage of tung oil-based carboxylic acid in the first extraction system is 20wt% to 25wt%; Preferably, the saponification rate of the first extraction system is 40% to 50%; Preferably, the mass percentage of the synergist in the first extraction system is 5wt% to 10wt%; Preferably, the volume ratio of the first extraction system to the second liquid phase is 3 to 6:1; Preferably, the first stripping adopts a sulfuric acid solution; Preferably, the concentration of the sulfuric acid solution in the first stripping is 2 to 5 mol / L; Preferably, between the first extraction and the first stripping, a first washing step is further included; Preferably, the wash acid of the first wash comprises a sulfuric acid solution; Preferably, the volume ratio of the first extraction system to the washing acid in the first washing is 20 to 60:1; Preferably, the washing acid concentration of the first washing is 0.5-0.8 mol / L.

8. The method according to any one of claims 1 to 7, characterized in that: The copper removal in step (4) includes resin copper removal; Preferably, the resin copper removal comprises: removing copper from the first stripping solution with a copper removal resin to obtain a copper-removed solution, and analyzing the copper-removed resin with an analytical acid to obtain a copper-containing analytical solution; Preferably, the analytical acid is sulfuric acid; Preferably, the concentration of the analytical acid is 1 to 2 mol / L; Preferably, the copper-containing analytical solution is subjected to manganese powder replacement to remove copper to prepare sponge copper; Preferably, the amount of manganese powder added in the manganese powder replacement copper removal is 0.9 to 1 times the molar content of copper in the copper-containing analytical solution; Preferably, the manganese powder replacement copper removal comprises: mixing manganese powder and a copper-containing analytical solution to remove copper to obtain sponge copper and copper removal waste liquid.

9. The method according to any one of claims 1 to 8, characterized in that: The copper-removed liquid in step (4) is subjected to a second extraction by a second extraction system to remove zinc; Preferably, the second extraction system comprises an organic phosphoric acid compound and solvent oil; Preferably, the organophosphate compound in the second extraction system includes any one or a combination of at least two of P204, P507 or C272; Preferably, the mass percentage of the organic phosphoric acid extractant in the second extraction system is 2wt% to 10wt%; Preferably, the second extraction system is not subjected to saponification; Preferably, the solvent oil is sulfonated kerosene; Preferably, the volume ratio of the second extraction system to the copper-removed liquid is 0.8 to 1.2:1; Preferably, the second stripping adopts a sulfuric acid solution; Preferably, the concentration of the sulfuric acid solution in the second stripping is 3 to 5 mol / L; Preferably, a second washing is further included between the second extraction and the second stripping; Preferably, the wash acid of the second wash comprises a sulfuric acid solution; Preferably, the volume ratio of the second extraction system to the washing acid in the second washing is 20 to 60:1; Preferably, the washing acid concentration of the second washing is 0.3-0.5 mol / L.

10. The method according to any one of claims 1 to 9, characterized in that: The third extraction system of the third extraction in step (5) comprises an organic phosphoric acid compound and solvent oil; Preferably, the organophosphate compound in the third extraction system includes any one or a combination of at least two of P507, C272, P204, P227 or TBP; Preferably, the mass percentage of the organic phosphoric acid extractant in the third extraction system is 20wt% to 25wt%; Preferably, the saponification rate of the third extraction system is 40% to 45%; Preferably, the solvent oil in the third extraction system is sulfonated kerosene; Preferably, the volume ratio of the third extraction system to the first raffinate is 4 to 6:1; Preferably, the third stripping adopts a sulfuric acid solution; Preferably, the concentration of the sulfuric acid solution in the third stripping is 2 to 3 mol / L; Preferably, a third washing is further included between the third extraction and the third stripping; Preferably, the washing acid of the third washing comprises a hydrochloric acid solution; Preferably, the volume ratio of the third extraction system to the washing acid in the third washing is 40 to 60:1; Preferably, the concentration of the washing acid in the third washing is 0.3-0.6 mol / L; Preferably, the lithium-sodium solution is subjected to MVR evaporation and carbonization process to prepare lithium carbonate; Preferably, the third washing produces a cobalt-manganese-calcium-magnesium chloride solution; Preferably, the cobalt-containing manganese calcium magnesium chloride solution is subjected to a cobalt removal treatment with a cobalt removal resin and the cobalt removal resin is analyzed to obtain a cobalt sulfate analysis solution; Preferably, the cobalt removal treatment also produces a calcium-magnesium-containing solution; Preferably, the calcium-magnesium-containing solution is adjusted to a pH value of 13 or above by adding liquid alkali to precipitate calcium and magnesium, and the mixed system is subjected to solid-liquid separation to obtain calcium-magnesium hydroxide slag and a liquid after magnesium removal; Preferably, the magnesium-removed liquid is used as an alkali for saponification.

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