Method for recycling lithium ion battery waste

Abstract

The application belongs to the technical field of battery recycling, and particularly relates to a method for recycling lithium ion battery waste. The method for recycling lithium ion battery waste provided by the application comprises the processes of reduction leaching, iron powder copper removal, iron phosphate precipitation, iron and aluminum removal, calcium and magnesium removal, P204 manganese extraction, P507 nickel and cobalt extraction, and resin adsorption lithium extraction in sequence. The method can process various complex battery waste, and the elements such as nickel, cobalt, manganese, phosphorus, iron, copper and lithium in the waste can be recycled, and the economic benefit is high. The various residues and condensate produced in the process are treated, the nickel, cobalt and lithium can be deeply recycled, the economic benefit is improved, and zero emission is truly realized.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of battery recycling, and particularly relates to a method for recycling lithium ion battery waste. BACKGROUND

[0002] The batteries composed of positive electrode materials such as lithium cobaltate, lithium iron phosphate, lithium manganate and lithium nickel cobalt manganate are all lithium ion batteries, and the production processes of various battery manufacturers are not the same, resulting in extremely complex composition of the recovered waste lithium ion battery waste and different impurity contents. The existing process has the following problems: 1. only battery waste with single and simple composition can be treated, and the production line has poor compatibility; 2. adding alkali to remove iron and aluminum to form iron hydroxide and aluminum hydroxide colloid, resulting in increased loss of nickel, cobalt and lithium; 3. phosphorus and iron are removed as impurities, and cannot be effectively recycled; 4. various waste residues and waste water are produced, causing environmental pollution and loss of valuable metals, and the economy and environmental protection are poor.

[0003] Therefore, it is urgent to develop a recycling method for complex waste lithium ion battery waste which is simple to operate and easy to be applied in industry. SUMMARY

[0004] The present application is based on the discovery and understanding of the inventors on the following facts and problems:

[0005] The current lithium ion battery recycling process is divided into waste lithium iron phosphate recycling process and waste ternary recycling process. In the waste lithium iron phosphate recycling process, lithium in the waste battery waste is mainly recovered. In the waste ternary recycling process, lithium, nickel and cobalt are mainly recovered, and iron and phosphorus are removed as impurities. There is no recycling process for lithium, nickel, cobalt, iron, copper and phosphorus in complex materials after mixing of several lithium ion batteries.

[0006] The present application aims to at least solve one of the technical problems in the related art. To this end, the embodiments of the present application propose a method for recycling lithium ion battery waste, which can process various complex battery waste, and the elements such as nickel, cobalt, manganese, phosphorus, iron, copper and lithium in the waste can be recycled, the economic benefit is high, the various residues and waste water generated in the process are treated, the nickel, cobalt and lithium can be deeply recovered, and the economic benefit is improved while realizing zero emission.

[0007] The method for recycling lithium ion battery waste according to an embodiment of the present application comprises the following steps:

[0008] (1) Reductive leaching: adding water to the battery waste to adjust the slurry, adding acid and reducing agent for acid leaching, and separating the solid and liquid to obtain acid leaching residue and acid leaching liquid;

[0009] (2) Iron powder copper removal: iron powder is added to the acid leaching solution obtained in step (1), a displacement reaction is carried out, and then solid-liquid separation is performed to obtain sponge copper and a copper-removed solution;

[0010] (3) Ferric phosphate precipitation: a phosphorus source is added to the copper-removed solution obtained in step (2), hydrogen peroxide is added for oxidation, and then an alkali solution is added to adjust the pH for reaction, and then solid-liquid separation is performed to obtain a ferric phosphate precipitate and a ferric phosphate-removed solution;

[0011] (4) Iron and aluminum removal: lime is added to the ferric phosphate-removed solution obtained in step (3) to adjust the pH for reaction, and then solid-liquid separation is performed to obtain an iron and aluminum-removed solution and an iron and aluminum residue;

[0012] (5) Calcium and magnesium removal: a fluoride is added to the iron and aluminum-removed solution obtained in step (4) for reaction, and then solid-liquid separation is performed to obtain a calcium and magnesium-removed solution and a calcium and magnesium residue;

[0013] (6) P204 manganese extraction: the calcium and magnesium-removed solution obtained in step (5) is countercurrently extracted with a P204 organic solvent to obtain a manganese-rich organic solution and a manganese extraction raffinate;

[0014] (7) P507 nickel and cobalt extraction: the manganese extraction raffinate obtained in step (6) is countercurrently extracted with a P507 organic solvent to obtain an organic solvent loaded with nickel and cobalt and a raffinate;

[0015] (8) Resin adsorption lithium extraction: the raffinate obtained in step (7) enters a resin adsorption lithium extraction system for separation to obtain a lithium sulfate solution and a lithium-extracted solution.

[0016] The method for recycling lithium ion battery waste according to the embodiments of the present application has the following advantages and technical effects: 1. The method according to the embodiments of the present application can process various complex battery waste, and the elements such as nickel, cobalt, manganese, phosphorus, iron and lithium in the waste can be recycled, and the economic benefit is high; 2. The method according to the embodiments of the present application adds lime to the ferric phosphate-removed solution for reaction, which can remove trace amounts of iron, aluminum and phosphorus in the solution in the form of precipitate, and at the same time, avoid the formation of viscous iron hydroxide and aluminum hydroxide precipitate to cause the adsorption loss of valuable metals, thereby improving the recovery rate of valuable metals; 3. The method according to the embodiments of the present application adds a fluoride to the iron and aluminum-removed solution, which can convert calcium and magnesium in the solution into fluoride precipitate for removal.

[0017] In some embodiments, in step (1), the acid includes at least one of sulfuric acid, hydrochloric acid and nitric acid, and the reducing agent includes at least one of hydrogen peroxide and sodium metabisulfite; and / or, the acid leaching temperature is 60-90℃, the acid leaching time is 2-4h, and the pH is maintained in the range of 0-2.

[0018] In some embodiments, in the step (2), the amount of the iron powder added is 1-3 times the total mass of iron and copper in the acid leaching solution, the reaction temperature of the displacement reaction is 30-80℃, and the reaction time is 10-60 min.

[0019] In some embodiments, in the step (3), the amount of the phosphorus source added is adjusted to a molar ratio of iron to phosphorus of 1-1.2:1, the amount of the hydrogen peroxide added is 0.8-1.5 times the molar amount of iron, the pH is adjusted to 1.6-2.5 by adding an alkali solution, and / or the reaction is stirred at 60-90℃ for 30-200 min.

[0020] In some embodiments, in the step (3), the phosphorus source comprises at least one of phosphoric acid, ammonium dihydrogen phosphate, diammonium hydrogen phosphate, lithium dihydrogen phosphate, trisodium phosphate, and sodium dihydrogen phosphate, and / or the alkali solution comprises at least one of sodium hydroxide, ammonia, potassium hydroxide, lithium hydroxide, sodium carbonate, potassium carbonate, ammonium carbonate, sodium bicarbonate, potassium bicarbonate, and ammonium bicarbonate.

[0021] In some embodiments, in the step (4), the pH is adjusted to 4.0-5.0, and the reaction is carried out at 60-90℃ for 1-3 h.

[0022] In some embodiments, in the step (5), the amount of the fluoride added is 10-20 times the total weight of calcium and magnesium in the solution after removal of iron and aluminum, the reaction is carried out at 70-90℃ for 2-4 h, and / or the fluoride comprises at least one of sodium fluoride and ammonium fluoride.

[0023] In some embodiments, in the step (6), the O / A ratio during the P204 manganese extraction is 1-5:1, and / or the manganese-rich organic solution is back-extracted with dilute sulfuric acid to obtain a manganese sulfate solution, the O / A ratio is 1-5:1, the concentration of the dilute sulfuric acid is 100-200 g / L, and the content of manganese in the manganese sulfate solution is 100-120 g / L.

[0024] In some embodiments, in the step (7), the O / A ratio during the P507 nickel-cobalt extraction is 1-4:1, and / or the nickel-cobalt-loaded organic solution is back-extracted with dilute sulfuric acid to obtain a nickel-cobalt sulfate solution, the O / A ratio is 1-3:1, and the concentration of the dilute sulfuric acid is 100-200 g / L.

[0025] In some embodiments, the step (9) is further included, in which the solution after lithium extraction obtained in the step (8) is evaporated to obtain condensed water and impurity salts. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 is a process flow chart of Example 1. DETAILED DESCRIPTION

[0027] Embodiments of the present application are described in detail below with reference to the attached drawing figures, wherein the examples of embodiments are shown. The embodiments described below are examples intended to provide an explanation of the present application and are not intended to restrict the present application.

[0028] The method for recycling lithium ion battery waste of the embodiment of the present application comprises the following steps:

[0029] (1) Reductive leaching: After the battery waste is slurried with water, acid and reducing agent are added for acid leaching, and solid-liquid separation is performed to obtain acid leaching residue and acid leaching solution;

[0030] (2) Iron powder copper removal: Iron powder is added to the acid leaching solution obtained in step (1) to perform displacement reaction, and then solid-liquid separation is performed to obtain sponge copper and copper-removed solution;

[0031] (3) Iron phosphate precipitation: A phosphorus source is added to the copper-removed solution obtained in step (2), hydrogen peroxide is added for oxidation, and then an alkali solution is added to adjust the pH for reaction, and then solid-liquid separation is performed to obtain iron phosphate precipitate and iron phosphate precipitation solution;

[0032] (4) Iron and aluminum removal: Lime is added to the iron phosphate precipitation solution obtained in step (3) to adjust the pH for reaction, and then solid-liquid separation is performed to obtain iron and aluminum removal solution and iron and aluminum residue;

[0033] (5) Calcium and magnesium removal: Fluoride is added to the iron and aluminum removal solution obtained in step (4) for reaction, and then solid-liquid separation is performed to obtain calcium and magnesium removal solution and calcium and magnesium residue;

[0034] (6) P204 manganese extraction: The calcium and magnesium removal solution obtained in step (5) is countercurrently extracted with P204 organic solvent to obtain manganese-rich organic solution and manganese extraction raffinate;

[0035] (7) P507 nickel and cobalt extraction: The manganese extraction raffinate obtained in step (6) is countercurrently extracted with P507 organic solvent to obtain nickel and cobalt-loaded organic solvent and raffinate;

[0036] (8) Resin adsorption lithium extraction: The raffinate obtained in step (7) enters the resin adsorption lithium extraction system for separation to obtain lithium sulfate solution and lithium extraction solution.

[0037] The method for recycling lithium ion battery waste of the embodiment of the application can process various complex battery waste, and the elements such as nickel, cobalt, manganese, phosphorus, iron and lithium in the waste can be recycled and utilized, and the economic benefit is high; the lime is added to the post-phosphorus iron precipitation solution to react, so that the trace iron aluminum phosphorus in the solution is removed in the form of a precipitate, the formation of viscous iron hydroxide and aluminum hydroxide precipitates is avoided, the adsorption loss of valuable metals is avoided, the recovery rate of valuable metals is improved, and the fluoride is added to the post-iron aluminum solution to convert the calcium and magnesium in the solution into fluoride precipitates and remove them.

[0038] In some embodiments, preferably, in the step (1), the acid comprises at least one of sulfuric acid, hydrochloric acid and nitric acid, and the reducing agent comprises at least one of hydrogen peroxide and sodium metabisulfite; and / or, the temperature of the acid leaching is 60-90 DEG C, the acid leaching time is 2-4 h, and the pH is maintained in the range of 0-2. Further preferably, the solid-liquid ratio of the battery waste to water is 1-3:1; and the battery waste comprises at least one of lithium iron phosphate, lithium cobaltate, lithium manganate, lithium nickel cobalt manganate and lithium manganese iron phosphate. In the embodiment of the application, the strong acid is used for reduction leaching treatment, and the pH is maintained in the range of 2-4, so that the metal leaching rate can be improved.

[0039] In some embodiments, preferably, in the step (2), the addition amount of the iron powder is 1-3 times the sum of the mass of iron and copper in the acid leaching solution, and the reaction temperature of the displacement reaction is 30-80 DEG C, and the reaction time is 10-60 min. In the embodiment of the application, the iron powder is used to remove copper by displacement reaction, which can effectively remove copper and does not introduce new impurities into the system, and the treatment cost is low.

[0040] In some embodiments, preferably, in the step (3), the amount of the phosphorus source is added to adjust the molar ratio of iron to phosphorus to 1-1.2:1, the amount of hydrogen peroxide is 0.8-1.5 times the molar amount of iron, the pH is adjusted to 1.6-2.5 by adding an alkali solution; and / or, the reaction is stirred at 60-90°C for 30-200 min. Further preferably, in the step (3), the phosphorus source comprises at least one of phosphoric acid, ammonium dihydrogen phosphate, diammonium hydrogen phosphate, lithium dihydrogen phosphate, trisodium phosphate, sodium dihydrogen phosphate; and / or, the alkali solution comprises at least one of sodium hydroxide, ammonia, potassium hydroxide, lithium hydroxide, sodium carbonate, potassium carbonate, ammonium carbonate, sodium bicarbonate, potassium bicarbonate and ammonium bicarbonate. Still more preferably, after the addition of the ferric phosphate precipitate into a phosphoric acid solution for reaction, solid-liquid separation is performed, and the obtained solid is dried to obtain ferric phosphate dihydrate, the solid-liquid ratio of the ferric phosphate precipitate to the phosphoric acid solution is 1:2-5, the concentration of the phosphoric acid solution is 2-6 wt%, and / or, the reaction is performed at 90-95°C for 60-120 min. In the embodiments of the present application, by adding hydrogen peroxide, divalent iron is fully oxidized to trivalent iron, which rapidly reacts with the phosphorus source under suitable reaction conditions to form a ferric phosphate precipitate, and after treatment, ferric phosphate dihydrate is obtained, which can be used for the preparation of lithium iron phosphate batteries.

[0041] In some embodiments, preferably, in the step (4), the pH is adjusted to 4.0-5.0, and the reaction is performed at 60-90°C for 1-3 h. In the embodiments of the present application, under this reaction condition, the reaction can be rapidly performed, iron and aluminum can be efficiently removed, and the treatment efficiency is improved.

[0042] In some embodiments, preferably, in the step (5), the amount of the fluoride is 10-20 times the sum of the weights of calcium and magnesium in the solution after the removal of iron and aluminum, the reaction is performed at 70-90°C for 2-4 h; and / or, the fluoride comprises at least one of sodium fluoride and ammonium fluoride. In the embodiments of the present application, the amount of the fluoride is controlled within a reasonable range. If the amount of the fluoride is too small, the impurities cannot be completely removed, if the amount of the fluoride is too large, the consumption of raw materials is increased, unnecessary waste is caused, the amount of calcium-magnesium residue is increased, and the amount of nickel loss is increased. The reaction is performed at a suitable temperature, which is beneficial to the dissolution of the fluoride, accelerates the reaction rate, and shortens the treatment time.

[0043] In some embodiments, preferably, in the step (6), the O / A ratio is 1-5:1 when the P204 manganese extraction is performed; and / or, the manganese-rich organic solution is back-extracted with dilute sulfuric acid to obtain a manganese sulfate solution, the O / A ratio is 1-5:1, the concentration of the dilute sulfuric acid is 100-200 g / L, and the content of manganese in the manganese sulfate solution is 100-120 g / L. Further preferably, the saponification rate of the P204 organic solvent is 60-70%, and the concentration is 30-40%. More preferably, activated carbon is added to the manganese sulfate solution to adsorb and remove oil, and the amount of the activated carbon added is 2-5 g / L. In the embodiments of the present application, the saponification rate and the concentration of the P204 organic solvent can improve the extraction rate; after the manganese sulfate solution is adsorbed and oil is removed by the activated carbon, the oil content in the solution is <0.5 mg / L, and the solution can be directly used for the preparation of ternary precursors, thereby realizing the recycling of resources.

[0044] In some embodiments, preferably, in the step (7), the O / A ratio is 1-4:1 when the P507 nickel-cobalt extraction is performed; and / or, the nickel-cobalt-loaded organic solution is back-extracted with dilute sulfuric acid to obtain a nickel-cobalt sulfate solution, the O / A ratio is 1-3:1, and the concentration of the dilute sulfuric acid is 100-200 g / L. Further preferably, the saponification rate of the P507 organic solvent is 60-70%, and the concentration is 25-30%. More preferably, activated carbon is added to the nickel-cobalt sulfate solution to adsorb and remove oil, and the amount of the activated carbon added is 2-5 g / L. In the embodiments of the present application, the saponification rate and the concentration of the P507 organic solvent can improve the extraction rate; after the nickel-cobalt sulfate solution is adsorbed and oil is removed by the activated carbon, the oil content in the solution is <0.5 mg / L, and the solution can be directly used for the preparation of ternary precursors, thereby realizing the recycling of resources.

[0045] In some embodiments, preferably, the resin is an aluminum-based resin purchased from JUWON. Further preferably, in the step (8), the lithium-extracted solution contains sodium, fluorine, phosphorus, COD, and the like. In the embodiments of the present application, the resin is used to extract lithium, which can separate fluorine, phosphorus, sodium, and COD from lithium, has high treatment efficiency, can greatly shorten the treatment period, and the recovered lithium has high purity, which can meet the needs of battery use.

[0046] In some embodiments, preferably, the step (9) is further included, in which the lithium-extracted solution obtained in the step (8) is evaporated to obtain condensed water and impurity salt. Further preferably, in the step (9), the condensed water is returned to the reduction leaching system of the step (1), and the impurity salt, acid leaching residue, iron-aluminum residue, and calcium-magnesium residue are put into corresponding electric furnaces for smelting to obtain nickel sulfur and glassy building materials. In the embodiments of the present application, the obtained condensed water and various residues are treated and recycled, which improves economic benefits and truly realizes zero emission.

[0047] The technical solutions of the present application will be described in detail below in combination with specific embodiments and drawings.

[0048] Example 1

[0049] (1) 500g of material was weighed, the content of each component in the material was shown in Table 1, 1000g of water was added to the material to obtain a slurry, 450mL of concentrated sulfuric acid and 300mL of hydrogen peroxide were slowly added to the slurry, the temperature of the water bath was maintained at 60℃, the reaction was carried out for 3h until the pH remained unchanged at 1.0, and then the slurry was filtered to obtain 375g of acid leaching residue and 1500mL of acid leaching solution, the analysis results of the acid leaching residue were shown in Table 2;

[0050] (2) 20g of iron powder was added to the acid leaching solution, the reaction was carried out at 60℃ for 30min, and then the slurry was filtered to obtain 21g of sponge copper and 1500mL of copper-removed solution, the analysis results of the sponge copper were shown in Table 2;

[0051] (3) 31g of analytical pure phosphoric acid was added to the copper-removed solution, 50mL of hydrogen peroxide was slowly added after stirring, and then saturated sodium carbonate solution was added to adjust the pH to 1.8, the reaction was carried out at 90℃ for 100min, and then the slurry was filtered to obtain phosphorus iron precipitation solution and 162g of wet weight phosphorus iron, the analysis results of the wet weight phosphorus iron were shown in Table 3; the wet weight phosphorus iron was added to 500ml of 4% phosphoric acid solution, the reaction was carried out at 92℃ for 2h, the slurry was filtered, and the filter cake was dried in an oven at 80℃ to obtain 80g of pink dihydrate iron phosphate;

[0052] (4) 200g of lime was added to the phosphorus iron precipitation solution at 60℃, the pH was adjusted to 4.5, the reaction was carried out for 1h, and then the slurry was filtered to obtain 280g of iron and aluminum residue and 1300mL of iron and aluminum-removed solution, the analysis results of the iron and aluminum residue were shown in Table 2;

[0053] (5) 6g of sodium fluoride was added to the iron and aluminum-removed solution at 80℃, the reaction was carried out for 120min, and then the slurry was filtered to obtain 11g of calcium and magnesium residue and 1200mL of calcium and magnesium-removed solution, the analysis results of the calcium and magnesium residue were shown in Table 2;

[0054] (6) P204 organic solvent with a saponification rate of 60% (P204 concentration of 30wt%) was extracted by three-stage countercurrent extraction with O / A=4:1 to obtain negative manganese organic phase and manganese extraction residual liquid, the negative manganese organic phase was back-extracted with 100g / L sulfuric acid with O / A=5:1 to obtain 600mL of manganese sulfate solution, 3g of activated carbon was added to the manganese sulfate solution to remove oil by stirring, and then a high-purity manganese sulfate solution meeting the requirements of ternary precursor preparation was obtained, the analysis results of the manganese sulfate were shown in Table 3;

[0055] (7) The manganese raffinate is extracted with P507 organic solvent (P507 concentration 40wt%) with a saponification rate of 50% by three-stage countercurrent extraction at O / A = 4:1 to obtain a negative nickel-cobalt organic phase and 1200 mL of raffinate. The negative nickel-cobalt organic phase is stripped with 100 g / L sulfuric acid at O / A = 3:1 to obtain 600 mL of nickel-cobalt sulfate solution. 3g of activated carbon is added to the nickel-cobalt sulfate solution and stirred to remove oil to obtain a high-purity nickel-cobalt sulfate solution meeting the requirements for preparation of ternary precursors. The analysis results of the nickel-cobalt sulfate are shown in Table 3.

[0056] (8) The 1200 mL of raffinate is slowly flowed through the resin adsorption lithium extraction system, and 100 mL of sulfuric acid washing is used for backwashing to obtain 100 mL of high-purity lithium sulfate solution and 1200 mL of lithium extraction solution. The analysis results of the lithium sulfate are shown in Table 3.

[0057] (9) The lithium extraction solution is sent to evaporation, the condensed water is returned to the reduction leaching system of step (1), and the mixed salt, acid leaching residue, iron and aluminum residue, and calcium and magnesium residue are put into the corresponding electric furnace for smelting to obtain nickel sulfur and glassy building materials. The analysis results of the nickel sulfur and glassy building materials are shown in Table 3.

[0058] After calculation, the nickel yield in this embodiment is 99.8%, the cobalt yield is 98.9%, and the lithium yield is 94.35%.

[0059] Example 2

[0060] (1) 500g of material is weighed, the content of each component in the material is shown in Table 1, 500g of water is added and stirred to obtain a slurry, 31wt% hydrochloric acid and 100mL hydrogen peroxide are slowly added to the slurry, the water bath temperature is maintained at 80℃, the reaction is carried out for 2h until the pH remains at 1.5, and then filtration is carried out to obtain 15g of acid leaching residue and 1700mL of acid leaching solution;

[0061] (2) 19.5g of iron powder is added to the acid leaching solution, and the reaction is carried out at 80℃ for 30min, and then filtration is carried out to obtain 20g of sponge copper and 1700mL of copper-removed solution;

[0062] (3) 55g of ammonium dihydrogen phosphate is added to the copper-removed solution, 200mL of hydrogen peroxide is slowly added after stirring, and 2mol / L sodium hydroxide solution is added to adjust the pH to 2.0, and the reaction is carried out at 70℃ for 60min, and then filtration is carried out to obtain 410g of wet weight iron phosphate and 1800mL of iron phosphate precipitation solution. The wet weight iron phosphate is added to 1500mL of 6% phosphoric acid solution, and the reaction is carried out at 90℃ for 1h, and then filtration is carried out, and the filter cake is dried in an oven at 80℃ to obtain 205g of pink iron phosphate dihydrate;

[0063] (4) adding 500 g lime milk (containing lime 250 g) to the post-iron phosphate sediment solution at 70 °C, adjusting the pH to 5.0, stirring for 2 h, filtering to obtain 370 g iron and aluminum residues and 2000 mL post-iron and aluminum removal solution;

[0064] (5) adding 20 g ammonium fluoride to the post-iron and aluminum removal solution at 90 °C, stirring for 150 min, filtering to obtain 35 g calcium and magnesium residues and 2000 mL post-calcium and magnesium removal solution;

[0065] (6) P204 organic solvent with a saponification rate of 50% (P204 concentration 20 wt%) is extracted by three-stage countercurrent extraction with O / A = 1:1 to obtain a negative manganese organic phase and a manganese extraction residual solution, and the negative manganese organic phase is back-extracted with 200 g / L sulfuric acid with O / A = 5:1 to obtain 1000 mL manganese sulfate solution, and 2 g activated carbon is added to the manganese sulfate solution to stir and remove oil to obtain a high-purity manganese sulfate solution meeting the requirements of ternary precursor preparation;

[0066] (7) P507 organic solvent with a saponification rate of 50% (P507 concentration 40 wt%) is extracted by two-stage countercurrent extraction with O / A = 3:1 to obtain a negative nickel and cobalt organic phase and 2000 mL raffinate, and the negative cobalt organic phase is back-extracted with 100 g / L sulfuric acid with O / A = 3:1 to obtain 800 mL cobalt sulfate solution, and 2 g activated carbon is added to the cobalt sulfate solution to stir and remove oil to obtain a high-purity cobalt sulfate solution meeting the requirements of ternary precursor preparation;

[0067] (8) 2000 mL of raffinate is slowly flowed through the resin adsorption lithium extraction system, and after 100 mL of sulfuric acid washing backwash, 100 mL of high-purity lithium sulfate solution and 2000 mL of post-lithium extraction solution are obtained;

[0068] (9) The post-lithium extraction solution is sent to the miscellaneous salt evaporation, and various residues are sent to the electric furnace smelting.

[0069] After calculation, the nickel recovery rate in this embodiment is 99.5%, the cobalt recovery rate is 98.3%, and the lithium recovery rate is 94.3%.

[0070] Comparative Example 1

[0071] The treatment method of this comparative example is the same as that of Example 1, except that in step (4), sodium hydroxide solution is added to the post-iron phosphate sediment solution, the pH is adjusted to 4.5, and the iron and aluminum removal reaction is carried out.

[0072] The nickel content in the iron and aluminum residues is as high as 6.3%, the cobalt content is as high as 1.5%, and the lithium content is 0.96%, and the final calculation shows that the nickel recovery rate is 90.6%, the cobalt recovery rate is 92.5%, and the lithium recovery rate is 88.7%.

[0073] Table 1 Various complex battery waste component table (%)

[0074] Ni Co Mn Li Cu Al Fe Mg Ca Zn F P C Example 1 11.2 5.41 11.83 3.01 2.2 1.95 0.93 0.11 0.26 0.03 0.75 0.66 37.9 Example 2 / 18.4 36.22 4.82 1.3 1.87 8.54 0.23 0.02 0.01 0.55 4.53 1.5

[0075] Table 2 Analysis of each slag in Example 1 (1 ppm = 0.0001%)

[0076]

[0077]

[0078] Table 3 Analysis of each product in Example 1

[0079]

[0080] In the present application, the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" mean that a particular feature, structure, material, or characteristic being described is included in at least one embodiment or example of the present application. The illustrative appearances of the above-mentioned terms in various places in the specification are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics can be combined in any suitable manner in one or more embodiments or examples. Moreover, the terms "first", "second", "third", etc. are used herein merely as identifiers for different elements, regions, or layers, and are not intended to be taken literally, unless otherwise specified.

[0081] Although the above embodiments have been shown and described, it is to be understood that the above embodiments are exemplary, and are not to be construed as limiting the present application, and any changes, modifications, substitutions, and variations of the above embodiments made by those skilled in the art are within the scope of the present application.

Claims

1. A method for recycling lithium-ion battery waste, characterized in that, Includes the following steps: (1) Reduction leaching: Water is added to the battery waste to make a slurry, and then acid and reducing agent are added for acid leaching. Solid-liquid separation is performed to obtain acid leaching residue and acid leaching solution. The acid leaching temperature is 60~90℃, the acid leaching time is 2~4h, and the pH is maintained in the range of 0~2. (2) Iron powder to remove copper: Iron powder is added to the acid leaching solution obtained in step (1) to carry out a displacement reaction, and then solid-liquid separation is performed to obtain sponge copper and copper-removed liquid; (3) Precipitation of ferric phosphate: Add phosphorus source to the copper-removed liquid obtained in step (2), add hydrogen peroxide for oxidation, then add alkaline solution to adjust pH for reaction, and then separate solid and liquid to obtain ferric phosphate precipitate and ferric phosphate precipitate liquid; (4) Iron and aluminum removal: Lime is added to the liquid obtained after precipitating ferric phosphate in step (3) to adjust the pH and react. Then, solid-liquid separation is performed to obtain the liquid after iron and aluminum removal and iron and aluminum slag. The reaction is carried out at 60~90℃ for 1~3h. (5) Removal of calcium and magnesium: Fluoride is added to the liquid obtained after removing iron and aluminum in step (4) to carry out the reaction, and then the liquid obtained after removing calcium and magnesium and calcium and magnesium slag are separated by solid-liquid separation; the reaction is carried out at 70~90℃ for 2~4h; (6) P204 manganese extraction: The solution obtained in step (5) after calcium and magnesium removal is subjected to countercurrent extraction with P204 organic solvent to obtain a manganese-rich organic solution and manganese extraction residue; the O / A ratio is 1~5:1 when P204 manganese extraction is performed. (7) P507 full extraction of nickel and cobalt: The manganese extraction residue obtained in step (6) is subjected to countercurrent extraction with P507 organic solvent to obtain an organic solvent loaded with nickel and cobalt and the extraction residue; the O / A ratio is 1~4:1 when performing the P507 full extraction of nickel and cobalt. (8) Lithium extraction by resin adsorption: The raffinate obtained in step (7) is introduced into the lithium extraction by resin adsorption system for separation to obtain lithium sulfate solution and lithium extraction liquid.

2. The method for recycling lithium-ion battery waste according to claim 1, characterized in that, In step (1), the acid includes at least one of sulfuric acid, hydrochloric acid, and nitric acid, and the reducing agent includes at least one of hydrogen peroxide and sodium metabisulfite.

3. The method for recycling lithium-ion battery waste according to claim 1, characterized in that, In step (2), the amount of iron powder added is 1 to 3 times the sum of the mass of iron and copper in the acid leaching solution, the reaction temperature of the displacement reaction is 30 to 80°C, and the reaction time is 10 to 60 min.

4. The method for recycling lithium-ion battery waste according to claim 1, characterized in that, In step (3), the amount of phosphorus source added is based on adjusting the molar ratio of iron to phosphorus to 1~1.2:1, the amount of hydrogen peroxide added is 0.8~1.5 times the molar amount of iron, and an alkaline solution is added to adjust the pH to 1.6~2.5; and / or, the reaction is carried out by stirring at 60~90℃ for 30~200min.

5. The method for recycling lithium-ion battery waste according to claim 1 or 4, characterized in that, In step (3), the phosphorus source includes at least one of phosphoric acid, ammonium dihydrogen phosphate, diammonium hydrogen phosphate, lithium dihydrogen phosphate, trisodium phosphate, and sodium dihydrogen phosphate; and / or, the alkaline solution includes at least one of sodium hydroxide, ammonia, potassium hydroxide, lithium hydroxide, sodium carbonate, potassium carbonate, ammonium carbonate, sodium bicarbonate, potassium bicarbonate, and ammonium bicarbonate.

6. The method for recycling lithium-ion battery waste according to claim 1, characterized in that, In step (4), the pH is adjusted to 4.0~5.

0.

7. The method for recycling lithium-ion battery waste according to claim 1, characterized in that, In step (5), the amount of fluoride added is 10 to 20 times the sum of the weights of calcium and magnesium in the liquid after iron and aluminum removal; and / or, the fluoride includes at least one of sodium fluoride and ammonium fluoride.

8. The method for recycling lithium-ion battery waste according to claim 1, characterized in that, In step (6), the manganese-rich organic solution is back-extracted with dilute sulfuric acid to obtain a manganese sulfate solution with an O / A ratio of 1~5:1, a concentration of dilute sulfuric acid of 100~200g / L, and a manganese content of 100~120g / L in the manganese sulfate solution.

9. The method for recycling lithium-ion battery waste according to claim 1, characterized in that, In step (7), the nickel-cobalt loaded organic solvent is back-extracted with dilute sulfuric acid to obtain a nickel-cobalt sulfate solution with an O / A ratio of 1~3:1 and a concentration of 100~200g / L for the dilute sulfuric acid.

10. The method for recycling lithium-ion battery waste according to claim 1, characterized in that, It also includes step (9), which involves evaporating the lithium extraction liquid obtained in step (8) to obtain condensate and mixed salts.

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