A method for selectively recovering lithium, nickel, cobalt and manganese in waste lithium battery ternary positive electrode material

Abstract

The application provides a method for selectively recovering lithium, nickel, cobalt and manganese from waste lithium battery ternary positive electrode materials, and belongs to the field of lithium battery metal recovery. The method comprises at least the following steps in sequence: leaching lithium, nickel, cobalt and manganese from the waste lithium battery ternary positive electrode materials; precipitating lithium and nickel; and precipitating manganese cobalt oxalate dihydrate. The method does not use strong acid, and uses a solvent formed by chloroacetic acid and tetrabutylammonium chloride to completely dissolve the metals in the positive electrode of the waste lithium battery, and then different metals are recovered step by step. The method has a simple process, can realize the recovery and utilization of multiple metals under mild conditions, and is easy to regenerate.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of lithium battery metal recovery, in particular to a method for selectively recovering lithium, nickel, cobalt and manganese from waste lithium battery ternary positive electrode materials. BACKGROUND

[0002] The lithium, cobalt and nickel metal resources existing in waste lithium batteries are relatively scarce, and improper treatment will also harm the environment. Therefore, it is crucial to develop new technologies to recover useful metals from waste lithium batteries.

[0003] Currently, the recovery of useful metals from waste lithium batteries mainly includes fire recovery and wet recovery. Fire recovery is a method of treating lithium battery positive electrode materials by high temperature calcination to recover useful metals in the form of alloy. This method inevitably has the problems of poor recovery selectivity and high energy consumption. Wet recovery is more energy-efficient than fire recovery, and can purposefully enrich and recover metals in the positive electrode material. However, traditional wet metallurgy consumes a large amount of inorganic strong acid such as sulfuric acid and hydrochloric acid, generates a large amount of wastewater, causes equipment corrosion and resource waste. In recent years, some scholars have studied the use of organic acids such as formic acid and malic acid to replace inorganic strong acid to leach metals in the positive electrode material. This method is more environmentally friendly, but it takes a long time and the cost of leaching agent is also relatively expensive, for example, the price of malic acid is about 40 times that of concentrated sulfuric acid.

[0004] Therefore, it is urgent to develop an economical, green, efficient and energy-saving method to recover useful metals from waste lithium batteries.

[0005] In view of this, the present application is proposed. SUMMARY

[0006] The purpose of the present application is to provide a method for selectively recovering lithium, nickel, cobalt and manganese from waste lithium battery ternary positive electrode materials, which does not use strong acid, uses a solvent formed by chloroacetic acid and tetrabutylammonium chloride to completely dissolve the metals in the positive electrode of the waste lithium battery, and then recovers different metals step by step; the method has a simple process and can realize the recovery and utilization of multiple metals under mild conditions, and is easy to regenerate.

[0007] To achieve the above purpose, the technical scheme of the present application is as follows:

[0008] A method for selectively recovering lithium, nickel, cobalt and manganese from waste lithium battery ternary positive electrode materials, at least comprising the following steps in sequence: leaching lithium, nickel, cobalt and manganese from the waste lithium battery ternary positive electrode material; precipitating lithium and nickel; precipitating manganese cobalt oxalate dihydrate.

[0009] Further, the leaching of lithium, nickel, cobalt and manganese from the waste lithium battery ternary positive electrode material is to add the waste lithium battery ternary positive electrode material to the prepared solvent, add oxalic acid, heat and stir, and leach lithium, nickel, cobalt and manganese.

[0010] Preferably, the solvent is prepared by mixing chloroacetic acid and tetrabutylammonium chloride and first heating and stirring. The selection of the solvent is very crucial to the present application, which should be able to dissolve metal ions such as lithium, nickel, cobalt and manganese, and also to achieve subsequent selective separation. Chloroacetic acid belongs to a strong acid organic acid, which is conducive to the dissolution of the positive electrode material. Tetrabutylammonium chloride can provide chloride ions and has strong coordination effect, which can combine with metals such as cobalt, manganese and nickel, and is conducive to dissolution. After mixing chloroacetic acid and tetrabutylammonium chloride, salts of lithium, nickel, cobalt and manganese can be formed and the four metals can be dissolved. When oxalic acid is added to the solvent, lithium oxalate and nickel oxalate are not dissolved in the solvent, resulting in the separation of lithium and nickel first; when oxalic acid aqueous solution is added, cobalt oxalate and manganese oxalate are not dissolved in the solvent containing the solvent, so that cobalt and manganese are recovered. If a common strong acid such as sulfuric acid or nitric acid is used, the four metals can be dissolved, but selective separation cannot occur, especially lithium cannot be separated. If a solvent with too weak acidity is used, it is difficult to dissolve the four metals, and the separation effect cannot be achieved.

[0011] Further, the first heating is heating to 65-75°C; in some embodiments of the present application, the heating temperature can be any value between 65°C, 66°C, 67°C, 68°C, 69°C, 70°C, 71°C, 72°C, 73°C, 74°C and 75°C. Mixing and heating chloroacetic acid and tetrabutylammonium chloride can quickly form a solvent, and without heating, a long mixing time is required, and the performance of the solvent for leaching the metal cannot be fully utilized.

[0012] Preferably, the molar ratio of chloroacetic acid to tetrabutylammonium chloride is 2.8:1-3.2:1. In some embodiments of the present application, the molar ratio of chloroacetic acid to tetrabutylammonium chloride can be any value between 2.8:1, 2.9:1, 3:1, 3.1:1 and 3.2:1. If the amount of chloroacetic acid is small, the viscosity of the solvent is large, and the acidity will also decrease, which is not conducive to the dissolution of the positive electrode material. When more chloroacetic acid is added, the concentration of tetrabutylammonium chloride decreases, and the concentration of chloride ions decreases, which is not conducive to the complexation of chloride ions and metal ions, and further not conducive to dissolution, and the leaching rate decreases. At the same time, too much chloroacetic acid is not conducive to the subsequent precipitation of lithium oxalate.

[0013] Further, the amount of oxalic acid added is 4.5-8.9 g / L.

[0014] The oxalic acid is added to protect the solvent and act as a reducing agent, which can prevent the solvent from being oxidized by the high valence cobalt and manganese in the metal powder. If the amount of oxalic acid is too much, lithium and nickel will be precipitated, which is not conducive to the dissolution of a large amount of metal. If the amount of oxalic acid is too low, the high valence cobalt and manganese cannot be completely reduced, and the solvent cannot be fully protected. In some embodiments of the present application, the amount of oxalic acid can be any value between 4.5 g / L, 4.6 g / L, 4.7 g / L, 4.8 g / L, 4.9 g / L, 5 g / L, 5.1 g / L, 5.2 g / L, 5.3 g / L, 5.4 g / L, 5.5 g / L, 5.6 g / L, 5.7 g / L, 5.8 g / L, 5.9 g / L, 6 g / L, 6.1 g / L, 6.2 g / L, 6.3 g / L, 6.4 g / L, 6.5 g / L, 6.6 g / L, 6.7 g / L, 6.8 g / L, 6.9 g / L, 7 g / L, 7.1 g / L, 7.2 g / L, 7.3 g / L, 7.4 g / L, 7.5 g / L, 7.6 g / L, 7.7 g / L, 7.8 g / L, 7.9 g / L, 8 g / L, 8.1 g / L, 8.2 g / L, 8.3 g / L, 8.4 g / L, 8.5 g / L, 8.6 g / L, 8.7 g / L, 8.8 g / L, 8.9 g / L, etc.

[0015] Further, the solid-liquid ratio of the waste lithium battery ternary positive material to the solvent is 10-20 g / L. In some embodiments of the present application, the solid-liquid ratio can be any value between 10 g / L, 11 g / L, 12 g / L, 13 g / L, 14 g / L, 15 g / L, 16 g / L, 17 g / L, 18 g / L, 19 g / L, 20 g / L, etc.

[0016] Further, the heating temperature of the heating and stirring is 90-100°C, and the stirring time is 5-7h.

[0017] Further, the precipitation of lithium and nickel is to add oxalic acid to the leaching solution of lithium, nickel, cobalt and manganese in the waste lithium battery ternary positive material, and then selectively precipitate lithium and nickel after stirring. After filtration, a leaching solution containing cobalt and manganese and lithium oxalate and nickel oxalate dihydrate solid precipitate are obtained. Preferably, the stirring time is 30-60 min.

[0018] Further, the leaching solution is added with oxalic acid, and the amount of the oxalic acid added is 8-16 g / L. In some embodiments of the present application, the amount of the oxalic acid added can be any value between 8 g / L, 9 g / L, 10 g / L, 11 g / L, 12 g / L, 13 g / L, 14 g / L, 15 g / L, 16 g / L, etc. If the amount of the oxalic acid added is too low, the lithium and nickel in the leaching solution cannot be precipitated in large amounts. If the amount of the oxalic acid added is too high, resources will be wasted.

[0019] Further, the precipitated manganese cobalt oxalate dihydrate is obtained by adding an aqueous oxalic acid solution into the obtained leaching solution containing cobalt and manganese, and filtering to obtain a solid precipitate of manganese cobalt oxalate dihydrate and a leaching solution.

[0020] Preferably, the concentration of the aqueous oxalic acid solution is 0.1-0.2 mol / L, and the amount of the aqueous oxalic acid solution added is equal to the volume of the leaching solution containing cobalt and manganese. The aqueous oxalic acid solution with the concentration can precipitate the cobalt and manganese in the leaching solution in large amounts. In some embodiments of the present application, the concentration of the oxalic acid can be any value between 0.1 mol / L, 0.11 mol / L, 0.12 mol / L, 0.13 mol / L, 0.14 mol / L, 0.15 mol / L, 0.16 mol / L, 0.17 mol / L, 0.18 mol / L, 0.19 mol / L, 0.2 mol / L, etc.

[0021] After the water in the leaching solution is evaporated, the leaching agent can be used again to leach the lithium battery positive electrode material.

[0022] Compared with the prior art, the present application uses chloroacetic acid and tetrabutylammonium chloride as leaching solvents, optimizes the metal recovery process of the conventional waste ternary lithium battery positive electrode material, recovers the waste ternary lithium battery positive electrode material powder under mild conditions, and is easy to operate. The solvent is less polluting, easy to regenerate, can be recycled, and lithium, nickel, cobalt and manganese can be recovered by 100% during the recycling process of the solvent. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope of the present application.

[0024] Figure 1 The process flow chart of the present application;

[0025] Figure 2 The X-ray powder diffraction (XRD) pattern of the lithium oxalate and nickel oxalate dihydrate recovered in Embodiment 1 of the present application;

[0026] Figure 3 X-ray powder diffraction (XRD) pattern of the manganese cobalt oxalate dihydrate recovered in Example 1 of the present application. DETAILED DESCRIPTION

[0027] As used herein the terms "includes", "including", "has", "having", "comprises" and "comprising", or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus.

[0028] "Made by" is synonymous with "comprising". As used herein the terms "comprises", "comprising", "includes", "including", "has", "having" or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises a list of elements is not necessarily limited only to those elements but can include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus.

[0029] When expressing a range, a preferred range, or a range defined by a series of upper preferred values and lower preferred values for an equivalent, concentration, or other value or parameter, it is to be understood that all ranges formed by any pairings of an upper or preferred value with a lower or preferred value, whether or not the range is expressly disclosed, are specifically disclosed. For example, where a range "1-5" is disclosed, the described range is to be construed as including ranges "1-4", "1-3", "1-2", "1-2 and 4-5", "1-3 and 5", etc. When numerical ranges are described herein, unless the context indicates otherwise, the range is intended to include the values explicitly stated as the upper and lower limits of the range, as well as to include all integers and fractions within that range.

[0030] "and / or" is used to indicate one or both stated cases can occur, for example A and / or B includes (A and B) and (A or B).

[0031] The technical solutions of the present application will be described in detail below in conjunction with specific examples, but those skilled in the art will understand that the following examples are only used to illustrate the present application and should not be regarded as limiting the scope of the present application. If no specific conditions are specified in the examples, the conventional conditions or the conditions recommended by the manufacturer are used. If no manufacturer of the reagent or instrument is specified, it is a conventional product that can be obtained by commercial purchase. In the present application, there is no special limitation on the form of the reactor.

[0032] The mass content wt% of each element in the waste lithium battery ternary positive electrode material powder used in the examples of the present application is Ni: 20.34, Co: 17.75, Mn: 18.88, and Li: 6.08. The elemental analysis instrument used in the examples of the present application is ICP-OES (ICAP 6300, USA).

[0033] Example 1

[0034] A method for selectively recovering lithium, nickel, cobalt and manganese from waste lithium battery ternary cathode material, as shown in Figure 1 comprises the following steps:

[0035] (1) Mix 28.35 g of chloroacetic acid with 27.79 g of tetrabutylammonium chloride (molar ratio of 3:1), heat to 70°C, and stir to form a solvent.

[0036] (2) Weigh 0.8 g of waste lithium battery ternary cathode material powder, add it to 50 mL of the solvent obtained in step (1), and then add 0.356 g of oxalic acid. Heat and stir at 100°C for 7 h to obtain a leaching solution containing lithium, nickel, cobalt and manganese.

[0037] (3) Add 0.64 g of oxalic acid to the leaching solution and stir for 60 min.

[0038] (4) Filter the mixture obtained in step (3) to obtain a leaching solution and lithium oxalate and nickel oxalate dihydrate precipitates. Analyze the lithium and nickel elements in the precipitates using an ICP-OES (ICAP 6300, USA) instrument, and calculate the lithium element recovery rate to be 92% and the nickel element recovery rate to be 99%. The X-ray powder diffraction (XRD) pattern of the obtained lithium oxalate and nickel oxalate dihydrate is shown in Figure 2 . The obtained leaching solution is subjected to the next step.

[0039] (5) Add 50 mL of a 0.15 mol / L oxalic acid aqueous solution to the leaching solution obtained in step (4), and filter to obtain a cobalt manganese oxalate dihydrate precipitate and a leaching solution. Dry the precipitate to obtain a cobalt manganese oxalate dihydrate solid. Analyze the cobalt and manganese elements in the precipitate using an ICP-OES instrument, and calculate the cobalt element recovery rate to be 99% and the manganese element recovery rate to be 91%. The X-ray powder diffraction (XRD) pattern of the obtained cobalt manganese oxalate dihydrate is shown in Figure 3 .

[0040] (6) Collect the leaching solution in step (5), evaporate the water to obtain a regenerated leaching agent.

[0041] Repeat steps (2) to (6) 5 times using the regenerated leaching agent, and analyze the recovery rate of the metal elements in each recovery using an ICP-OES instrument. In the first two recoveries, the lithium, nickel, cobalt and manganese elements are all recovered at 100%. In the third recovery, the lithium element recovery rate is 98%, the nickel element recovery rate is 98%, the cobalt element recovery rate is 100%, and the manganese element recovery rate is 98%. In the fourth recovery, the lithium element recovery rate is 97%, the nickel element recovery rate is 97%, the cobalt element recovery rate is 100%, and the manganese element recovery rate is 101%. In the fifth recovery, the lithium element recovery rate is 96%, the nickel element recovery rate is 100%, the cobalt element recovery rate is 99%, and the manganese element recovery rate is 97%.

[0042] Example 2

[0043] A method for selectively recovering lithium, nickel, cobalt and manganese from waste lithium battery ternary cathode material, comprising the following steps:

[0044] (1) Mix 28.35 g of chloroacetic acid with 27.79 g of tetrabutylammonium chloride (molar ratio 3:1), heat to 70°C, and stir to form a solvent.

[0045] (2) Weigh 1 g of waste lithium battery ternary cathode material powder, add it to 50 mL of the solvent obtained in step (1), and then add 0.445 g of oxalic acid. Heat and stir at 100°C for 7 hours to leach out the lithium, nickel, cobalt and manganese.

[0046] (3) Add 0.8 g of oxalic acid to the leaching solution and stir for 60 minutes.

[0047] (4) Filter the mixture obtained in step (3) to obtain the leaching solution and lithium oxalate and nickel oxalate dihydrate precipitate. Analyze the lithium and nickel elements to calculate the lithium recovery rate of 89% and the nickel recovery rate of 97%. The obtained leaching solution is subjected to the next step.

[0048] (5) Add 50 mL of 0.2 mol / L oxalic acid aqueous solution to the leaching solution obtained in step (4), and filter to obtain manganese cobalt oxalate dihydrate precipitate and leaching solution. Dry the precipitate to obtain manganese cobalt oxalate dihydrate solid. Analyze the cobalt and manganese elements to calculate the cobalt recovery rate of 96% and the manganese recovery rate of 89%.

[0049] (6) Collect the leaching solution in step (5), evaporate the water to obtain the regenerated leaching agent.

[0050] Example 3

[0051] A method for selectively recovering lithium, nickel, cobalt and manganese from waste lithium battery ternary cathode material, comprising the following steps:

[0052] (1) Mix 28.35 g of chloroacetic acid with 27.79 g of tetrabutylammonium chloride (molar ratio 3:1), heat to 70°C, and stir to form a solvent.

[0053] (2) Weigh 0.5 g of waste lithium battery ternary cathode material powder, add it to 50 mL of the solvent obtained in step (1), and then add 0.222 g of oxalic acid. Heat and stir at 100°C for 7 hours to leach out the lithium, nickel, cobalt and manganese.

[0054] (3) Add 0.4 g of oxalic acid to the leaching solution and stir for 60 minutes.

[0055] (4) Filter the mixture obtained in step (3) to obtain the leaching solution and lithium oxalate and nickel oxalate dihydrate precipitates. Analyze the lithium and nickel elements therein, and calculate that the lithium element recovery rate is 92% and the nickel element recovery rate is 99%. The obtained leaching solution continues to the next step.

[0056] (5) Add 50 mL of 0.1 mol / L oxalic acid aqueous solution to the leaching solution obtained in step (4), and filter to obtain manganese cobalt oxalate dihydrate precipitates and a leaching solution. Dry the precipitates to obtain manganese cobalt oxalate dihydrate solids. Analyze the cobalt and manganese elements therein, and calculate that the cobalt element recovery rate is 99% and the manganese element recovery rate is 91%.

[0057] (6) Collect the leaching solution in step (5), evaporate the water, and obtain a regenerated leaching agent.

[0058] Example 4

[0059] A method for selectively recovering lithium, nickel, cobalt, and manganese from waste lithium battery ternary positive electrode material, comprising the following steps:

[0060] (1) Mix 28.35 g of chloroacetic acid with 27.79 g of tetrabutylammonium chloride (molar ratio of 3:1), heat to 70°C, and stir to form a solvent.

[0061] (2) Weigh 0.8 g of waste lithium battery ternary positive electrode material powder, add it to 50 mL of the solvent obtained in step (1), and then add 0.356 g of oxalic acid. Heat and stir at 90°C for 7 h to obtain a leaching solution containing lithium, nickel, cobalt, and manganese.

[0062] (3) Add 0.64 g of oxalic acid to the leaching solution and stir for 60 min.

[0063] (4) Filter the mixture obtained in step (3) to obtain the leaching solution and lithium oxalate and nickel oxalate dihydrate precipitates. Analyze the lithium and nickel elements therein, and calculate that the lithium element recovery rate is 88% and the nickel element recovery rate is 97%. The obtained leaching solution continues to the next step.

[0064] (5) Add 50 mL of 0.15 mol / L oxalic acid aqueous solution to the leaching solution obtained in step (4), and filter to obtain manganese cobalt oxalate dihydrate precipitates and a leaching solution. Dry the precipitates to obtain manganese cobalt oxalate dihydrate solids. Analyze the cobalt and manganese elements therein, and calculate that the cobalt element recovery rate is 93% and the manganese element recovery rate is 88%.

[0065] (6) Collect the leaching solution in step (5), evaporate the water, and obtain a regenerated leaching agent.

[0066] Example 5

[0067] A method for selectively recovering lithium, nickel, cobalt and manganese from waste lithium battery ternary cathode material, comprising the following steps:

[0068] (1) Mix 28.35 g of chloroacetic acid with 27.79 g of tetrabutylammonium chloride (molar ratio 3:1), heat to 70°C, and stir to form a solvent.

[0069] (2) Weigh 0.8 g of waste lithium battery ternary cathode material powder, add it to 50 mL of the solvent obtained in step (1), and then add 0.356 g of oxalic acid. Heat and stir at 100°C for 5 hours to leach out the lithium, nickel, cobalt and manganese.

[0070] (3) Add 0.64 g of oxalic acid to the leaching solution and stir for 60 minutes.

[0071] (4) Filter the mixture obtained in step (3) to obtain the leaching solution and lithium oxalate and nickel oxalate dihydrate precipitate. Analyze the lithium and nickel elements, and calculate that the lithium recovery rate is 90% and the nickel recovery rate is 97%. The obtained leaching solution is subjected to the next step.

[0072] (5) Add 50 mL of 0.15 mol / L oxalic acid aqueous solution to the leaching solution obtained in step (4), and after filtration, obtain manganese cobalt oxalate dihydrate precipitate and leaching solution. Dry the precipitate to obtain manganese cobalt oxalate dihydrate solid. Analyze the cobalt and manganese elements, and calculate that the cobalt recovery rate is 95% and the manganese recovery rate is 85%.

[0073] (6) Collect the leaching solution in step (5), evaporate the water to obtain regenerated leaching agent.

[0074] Example 6

[0075] A method for selectively recovering lithium, nickel, cobalt and manganese from waste lithium battery ternary cathode material, comprising the following steps:

[0076] (1) Mix 28.35 g of chloroacetic acid with 27.79 g of tetrabutylammonium chloride (molar ratio 3:1), heat to 70°C, and stir to form a solvent.

[0077] (2) Weigh 0.8 g of waste lithium battery ternary cathode material powder, add it to 50 mL of the solvent obtained in step (1), and then add 0.356 g of oxalic acid. Heat and stir at 100°C for 7 hours to leach out the lithium, nickel, cobalt and manganese.

[0078] (3) Add 0.64 g of oxalic acid to the leaching solution and stir for 30 minutes.

[0079] (4) Filter the mixture obtained in step (3) to obtain the leachate and lithium oxalate and nickel oxalate dihydrate precipitates. Analyze the lithium and nickel elements therein, and calculate that the lithium element recovery rate is 88% and the nickel element recovery rate is 98%. The obtained leachate continues to the next step.

[0080] (5) Add 50 mL of 0.15 mol / L oxalic acid aqueous solution to the leachate obtained in step (4), and filter to obtain manganese cobalt oxalate dihydrate precipitates and a leachate. Dry the precipitates to obtain manganese cobalt oxalate dihydrate solids. Analyze the cobalt and manganese elements therein, and calculate that the cobalt element recovery rate is 99% and the manganese element recovery rate is 91%.

[0081] (6) Collect the leachate in step (5), evaporate the water, and obtain a regenerated leaching agent.

[0082] Example 7

[0083] A method for selectively recovering lithium, nickel, cobalt and manganese from waste lithium battery ternary positive electrode material, comprising the following steps:

[0084] (1) Mix 26.46 g of chloroacetic acid with 27.79 g of tetrabutylammonium chloride (molar ratio of 2.8:1), heat to 65°C, and stir to form a solvent.

[0085] (2) Weigh 0.8 g of waste lithium battery ternary positive electrode material powder, add it to 50 mL of the solvent obtained in step (1), and then add 0.356 g of oxalic acid. Heat and stir at 100°C to leach for 7 h to obtain a leachate containing lithium, nickel, cobalt and manganese.

[0086] (3) Add 0.64 g of oxalic acid to the leachate and stir for 60 min.

[0087] (4) Filter the mixture obtained in step (3) to obtain the leachate and lithium oxalate and nickel oxalate dihydrate precipitates. Analyze the lithium and nickel elements therein, and calculate that the lithium element recovery rate is 91% and the nickel element recovery rate is 98%. The obtained leachate continues to the next step.

[0088] (5) Add 50 mL of 0.15 mol / L oxalic acid aqueous solution to the leachate obtained in step (4), and filter to obtain manganese cobalt oxalate dihydrate precipitates and a leachate. Dry the precipitates to obtain manganese cobalt oxalate dihydrate solids. Analyze the cobalt and manganese elements therein, and calculate that the cobalt element recovery rate is 99% and the manganese element recovery rate is 91%.

[0089] (6) Collect the leachate in step (5), evaporate the water, and obtain a regenerated leaching agent.

[0090] Example 8

[0091] A method for selectively recovering lithium, nickel, cobalt and manganese from waste lithium battery ternary cathode material, comprising the following steps:

[0092] (1) Mix 30.24 g of chloroacetic acid with 27.79 g of tetrabutylammonium chloride (molar ratio 3.2:1), heat to 75°C, and stir to form a solvent.

[0093] (2) Weigh 0.8 g of waste lithium battery ternary cathode material powder, add it to 50 mL of the solvent obtained in step (1), and then add 0.356 g of oxalic acid. Heat and stir at 100°C for 7 hours to leach out the lithium, nickel, cobalt and manganese.

[0094] (3) Add 0.64 g of oxalic acid to the leaching solution and stir for 60 minutes.

[0095] (4) Filter the mixture obtained in step (3) to obtain the leaching solution and lithium oxalate and nickel oxalate dihydrate precipitate. Analyze the lithium and nickel elements to calculate the lithium recovery rate of 90% and the nickel recovery rate of 99%. The obtained leaching solution is subjected to the next step.

[0096] (5) Add 50 mL of 0.15 mol / L oxalic acid aqueous solution to the leaching solution obtained in step (4), and after filtration, obtain manganese cobalt oxalate dihydrate precipitate and leaching solution. Dry the precipitate to obtain manganese cobalt oxalate dihydrate solid. Analyze the cobalt and manganese elements to calculate the cobalt recovery rate of 98% and the manganese recovery rate of 88%.

[0097] (6) Collect the leaching solution in step (5), evaporate the water to obtain the regenerated leaching agent.

[0098] Example 9

[0099] A method for selectively recovering lithium, nickel, cobalt and manganese from waste lithium battery ternary cathode material, comprising the following steps:

[0100] (1) Mix 28.35 g of chloroacetic acid with 27.79 g of tetrabutylammonium chloride (molar ratio 3:1), heat to 70°C, and stir to form a solvent.

[0101] (2) Weigh 0.8 g of waste lithium battery ternary cathode material powder, add it to 50 mL of the solvent obtained in step (1), and then add 0.3 g of oxalic acid. Heat and stir at 100°C for 7 hours to leach out the lithium, nickel, cobalt and manganese.

[0102] (3) Add 0.64 g of oxalic acid to the leaching solution and stir for 60 minutes.

[0103] (4) Filter the mixture obtained in step (3) to obtain the leachate and lithium oxalate and nickel oxalate dihydrate precipitates. Analyze the lithium and nickel elements therein, and calculate that the lithium element recovery rate is 92% and the nickel element recovery rate is 99%. The obtained leachate continues to the next step.

[0104] (5) Add 50 mL of 0.15 mol / L oxalic acid aqueous solution to the leachate obtained in step (4), and filter to obtain manganese cobalt oxalate dihydrate precipitates and a leachate. Dry the precipitates to obtain manganese cobalt oxalate dihydrate solids. Analyze the cobalt and manganese elements therein, and calculate that the cobalt element recovery rate is 97% and the manganese element recovery rate is 88%.

[0105] (6) Collect the leachate in step (5), evaporate the water, and obtain a regenerated leaching agent.

[0106] Example 10

[0107] A method for selectively recovering lithium, nickel, cobalt and manganese from waste lithium battery ternary positive electrode material, comprising the following steps:

[0108] (1) Mix 28.35 g of chloroacetic acid with 27.79 g of tetrabutylammonium chloride (molar ratio of 3:1), heat to 70°C, and stir to form a solvent.

[0109] (2) Weigh 0.8 g of waste lithium battery ternary positive electrode material powder, add it to 50 mL of the solvent obtained in step (1), and then add 0.4 g of oxalic acid. Heat and stir at 100°C to leach for 7 h to obtain a leachate containing lithium, nickel, cobalt and manganese.

[0110] (3) Add 0.64 g of oxalic acid to the leachate and stir for 60 min.

[0111] (4) Filter the mixture obtained in step (3) to obtain the leachate and lithium oxalate and nickel oxalate dihydrate precipitates. Analyze the lithium and nickel elements therein, and calculate that the lithium element recovery rate is 89% and the nickel element recovery rate is 93%. The obtained leachate continues to the next step.

[0112] (5) Add 50 mL of 0.15 mol / L oxalic acid aqueous solution to the leachate obtained in step (4), and filter to obtain manganese cobalt oxalate dihydrate precipitates and a leachate. Dry the precipitates to obtain manganese cobalt oxalate dihydrate solids. Analyze the cobalt and manganese elements therein, and calculate that the cobalt element recovery rate is 98% and the manganese element recovery rate is 90%.

[0113] (6) Collect the leachate in step (5), evaporate the water, and obtain a regenerated leaching agent.

[0114] Example 11

[0115] A method for selectively recovering lithium, nickel, cobalt and manganese from waste lithium battery ternary cathode material, comprising the following steps:

[0116] (1) Mix 28.35 g of chloroacetic acid with 27.79 g of tetrabutylammonium chloride (molar ratio 3:1), heat to 70°C, and stir to form a solvent.

[0117] (2) Weigh 0.8 g of waste lithium battery ternary cathode material powder, add it to 50 mL of the solvent obtained in step (1), and then add 0.356 g of oxalic acid. Heat and stir at 100°C for 7 hours to leach out the lithium, nickel, cobalt and manganese.

[0118] (3) Add 0.6 g of oxalic acid to the leaching solution and stir for 60 minutes.

[0119] (4) Filter the mixture obtained in step (3) to obtain the leaching solution and lithium oxalate and nickel oxalate dihydrate precipitate. Analyze the lithium and nickel elements to calculate the lithium recovery rate of 85% and the nickel recovery rate of 97%. The obtained leaching solution is subjected to the next step.

[0120] (5) Add 50 mL of 0.15 mol / L oxalic acid aqueous solution to the leaching solution obtained in step (4), and after filtration, obtain manganese cobalt oxalate dihydrate precipitate and leaching solution. Dry the precipitate to obtain manganese cobalt oxalate dihydrate solid. Analyze the cobalt and manganese elements to calculate the cobalt recovery rate of 99% and the manganese recovery rate of 91%.

[0121] (6) Collect the leaching solution in step (5), evaporate the water to obtain the regenerated leaching agent.

[0122] Example 12

[0123] A method for selectively recovering lithium, nickel, cobalt and manganese from waste lithium battery ternary cathode material, comprising the following steps:

[0124] (1) Mix 28.35 g of chloroacetic acid with 27.79 g of tetrabutylammonium chloride (molar ratio 3:1), heat to 70°C, and stir to form a solvent.

[0125] (2) Weigh 0.8 g of waste lithium battery ternary cathode material powder, add it to 50 mL of the solvent obtained in step (1), and then add 0.356 g of oxalic acid. Heat and stir at 100°C for 7 hours to leach out the lithium, nickel, cobalt and manganese.

[0126] (3) Add 0.7 g of oxalic acid to the leaching solution and stir for 60 minutes.

[0127] (4) Filter the mixture obtained in step (3) to obtain the leach liquor and lithium oxalate and nickel oxalate dihydrate precipitates. Analyze the lithium and nickel elements therein, and calculate that the lithium element recovery rate is 92%, the nickel element recovery rate is 99%, and the obtained leach liquor continues to the next step.

[0128] (5) Add 50 mL of a 0.15 mol / L oxalic acid aqueous solution to the leach liquor obtained in step (4), and after filtration, obtain manganese cobalt oxalate dihydrate precipitates and a leach liquor. Dry the precipitates to obtain manganese cobalt oxalate dihydrate solids. Analyze the cobalt and manganese elements therein, and calculate that the cobalt element recovery rate is 98%, the manganese element recovery rate is 90%.

[0129] (6) Collect the leach liquor in step (5), evaporate the water, and obtain a regenerated leaching agent.

[0130] Example 13

[0131] A method for selectively recovering lithium, nickel, cobalt, and manganese from waste lithium battery ternary positive electrode materials, comprising the following steps:

[0132] (1) Mix 28.35 g of chloroacetic acid with 27.79 g of tetrabutylammonium chloride (molar ratio of 3:1), heat to 70°C, and stir to form a solvent.

[0133] (2) Weigh 0.8 g of waste lithium battery ternary positive electrode material powder, add it to 50 mL of the solvent obtained in step (1), and then add 0.356 g of oxalic acid. Heat and stir at 100°C to leach for 7 h, and obtain a leach liquor containing lithium, nickel, cobalt, and manganese.

[0134] (3) Add 0.64 g of oxalic acid to the leach liquor and stir for 60 min.

[0135] (4) Filter the mixture obtained in step (3) to obtain the leach liquor and lithium oxalate and nickel oxalate dihydrate precipitates. Analyze the lithium and nickel elements therein, and calculate that the lithium element recovery rate is 92%, the nickel element recovery rate is 99%, and the obtained leach liquor continues to the next step.

[0136] (5) Add 50 mL of a 0.12 mol / L oxalic acid aqueous solution to the leach liquor obtained in step (4), and after filtration, obtain manganese cobalt oxalate dihydrate precipitates and a leach liquor. Dry the precipitates to obtain manganese cobalt oxalate dihydrate solids. Analyze the cobalt and manganese elements therein, and calculate that the cobalt element recovery rate is 95%, the manganese element recovery rate is 87%.

[0137] (6) Collect the leach liquor in step (5), evaporate the water, and obtain a regenerated leaching agent.

[0138] Comparative Example 1

[0139] The difference from Example 1 is that the molar ratio of chloroacetic acid to tetrabutylammonium chloride is 4:1, and steps (2) to (6) are not repeated after step (6). The lithium, nickel, cobalt and manganese elements obtained are analyzed, and the lithium element recovery rate is calculated to be 86%, the nickel element recovery rate is 90%, the cobalt element recovery rate is 86%, and the manganese element recovery rate is 83%. It can be seen that after the proportion of chloroacetic acid increases, the recovery rates of the four metals decrease at the same time.

[0140] Comparative Example 2

[0141] The difference from Example 1 is that the molar ratio of chloroacetic acid to tetrabutylammonium chloride is 2.5:1, and steps (2) to (6) are not repeated after step (6). During the stirring process, the resistance is large, the lithium, nickel, cobalt and manganese elements obtained are analyzed, and the lithium element recovery rate is calculated to be 90%, the nickel element recovery rate is 92%, the cobalt element recovery rate is 88%, and the manganese element recovery rate is 82%. It can be seen that after the proportion of chloroacetic acid decreases, due to the increase in viscosity and the decrease in solubility, the recovery rates of the four metals also decrease at the same time.

[0142] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and are not limited thereto; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent replacements for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

[0143] In addition, those skilled in the art can understand that although some embodiments herein include certain features rather than others included in other embodiments, the combination of features of different embodiments means that it is within the scope of the present application and forms different embodiments. For example, in the above claims, any one of the claimed embodiments can be used in any combination. The information disclosed in the BACKGROUND section is only intended to deepen the understanding of the overall background of the present application, and should not be regarded as acknowledging or implying in any form that the information constitutes prior art known to those skilled in the art.

Claims

1. A method for selectively recovering lithium, nickel, cobalt, and manganese from waste lithium-ion battery ternary cathode materials, characterized in that, The process includes, in at least the following order: leaching lithium, nickel, cobalt, and manganese from the waste lithium-ion battery ternary cathode material; precipitating lithium and nickel; and precipitating manganese cobalt oxalate dihydrate. The leaching of lithium, nickel, cobalt, and manganese from the waste lithium-ion battery ternary cathode material is carried out by adding the waste lithium-ion battery ternary cathode material to a prepared solvent, adding oxalic acid, heating and stirring to leach lithium, nickel, cobalt, and manganese; the solvent is prepared by mixing chloroacetic acid and tetrabutylammonium chloride and subjecting it to a first heating and stirring; the first heating is carried out at 65~75℃; the molar ratio of chloroacetic acid to tetrabutylammonium chloride is 2.8:1~3.2:1; the solid-liquid ratio of the waste lithium-ion battery ternary cathode material to the solvent is 10~20 g / L, and the amount of oxalic acid added is 4.5~8.9 g / L; The precipitated lithium and nickel are obtained by adding oxalic acid to the leachate after leaching lithium, nickel, cobalt and manganese from the waste lithium battery ternary cathode material, stirring and selectively precipitating lithium and nickel to obtain a leachate containing cobalt and manganese and solid precipitates of lithium oxalate and nickel oxalate dihydrate; when adding oxalic acid to the leachate, the amount of oxalic acid added is 8~16 g / L. The precipitated manganese cobalt oxalate dihydrate is obtained by adding an aqueous oxalic acid solution to the obtained cobalt and manganese-containing leachate, filtering, and then obtaining a solid precipitate of manganese cobalt oxalate dihydrate and a leachate. The concentration of the aqueous oxalic acid solution is 0.1~0.2 mol / L, and the amount of aqueous oxalic acid solution added is equal to the volume of the cobalt and manganese-containing leachate.

2. The method according to claim 1, characterized in that, The heating temperature for the heating and stirring is 90~100℃, and the stirring time is 5~7h.

3. The method according to claim 1, characterized in that, The leachate, after the water in the leachate has been evaporated, is used again to leach the waste lithium-ion ternary cathode material.

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