Recycling method of waste lithium ion battery waste

Abstract

The invention provides a recycling method of a waste lithium ion battery waste material. The recycling method comprises the following steps: mixing the lithium ion battery waste material with concentrated sulfuric acid, calcining, leaching in water, pyrolyzing and centrifuging to obtain a lithium sulfate product and water leaching residues; a leaching agent containing ionic liquid and chloride is added into the water leaching residues, and leaching liquid and leaching residues are obtained; chemically removing copper, iron and aluminum, and filtering to obtain iron and aluminum removed liquid and iron and aluminum slag; carrying out counter-current extraction on the iron and aluminum removed liquid and P204 to obtain manganese-rich organic liquid and manganese extraction residual liquid; the manganese-rich organic liquid is subjected to reverse extraction with dilute sulfuric acid, a manganese sulfate solution is obtained, and a ternary precursor or manganous-manganic oxide is prepared; carrying out countercurrent extraction on the manganese extraction raffinate and the co-extraction organic solvent to obtain a nickel-cobalt-loaded organic solvent and raffinate; the nickel and cobalt loaded organic solvent is subjected to reverse extraction with dilute sulfuric acid to obtain a nickel and cobalt sulfate solution, and the nickel and cobalt sulfate solution is deoiled to prepare a ternary precursor; the recycling method of the waste lithium ion battery waste provided by the invention is simple, efficient, green and environment-friendly, and is easy for industrial application.

Description

Technical Field

[0001] The invention relates to the technical field of battery recycling, and in particular to a method for recycling waste lithium-ion battery waste. Background Art

[0002] With the continuous expansion of the new energy vehicle industry, the power battery recycling market has huge space. my country's power battery recycling has ushered in its first peak. In 2022, the cumulative battery retirement volume in my country was about 277,000 tons. By 2025, the cumulative retirement volume is expected to exceed 802,500 tons, and the CAGR5 (compound annual growth rate in the next five years) will reach 31%. With the exponential growth of power battery retirement in the future, it is expected that by 2030, the power battery retirement volume in my country will reach 2.373 million tons, and the power battery recycling market size will reach 100 billion yuan. With the increase in the amount of scrapped lithium-ion batteries, their resource nature has received more and more attention. The development of lithium battery recycling will not only avoid resource waste and environmental pollution, but also generate considerable economic benefits and investment opportunities.

[0003] At present, the main methods for recycling waste lithium-ion batteries are pyrometallurgy and hydrometallurgy. Compared with pyrometallurgy, hydrometallurgy has many advantages. Hydrometallurgy technology has the advantages of high metal recovery rate, high purity of recycled products, and high product added value, making it a research hotspot for recycling waste lithium-ion batteries. However, the traditional hydrometallurgical recycling process is long, the recycling process consumes a high amount of inorganic acid, produces toxic and harmful gases, and has a large carbon emission, which makes it difficult to meet the process requirements of efficient and green recycling.

[0004] Therefore, there is an urgent need to develop a simple, efficient, green, environmentally friendly, and industrially applicable method for recycling waste lithium-ion battery waste. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a simple, efficient, green, environmentally friendly and industrially applicable method for recycling waste lithium-ion battery waste.

[0006] In order to solve the above technical problems, the present invention provides a method for recycling waste lithium-ion battery waste, comprising the following steps:

[0007] The lithium-ion battery waste is mixed with concentrated sulfuric acid and then calcined to obtain a calcined material, the calcined material is soaked in water to obtain a water-leached residue and a lithium-rich solution, and the lithium-rich solution is pyrolyzed and centrifuged to obtain a lithium sulfate product;

[0008] The water-leached residue is leached in a leaching agent containing an ionic liquid and chloride, and the leaching solution and the leaching residue are filtered;

[0009] Add iron powder and / or manganese powder to the leaching solution to remove copper, and filter to obtain sponge copper and copper-removed solution;

[0010] Adding alkaline regulator to the copper-removed liquid to remove iron and aluminum, filtering to obtain the iron-removed liquid and iron-aluminum slag;

[0011] The liquid after iron and aluminum removal is counter-currently extracted with P204 to obtain manganese-rich organic liquid and manganese-extracted residual liquid;

[0012] The manganese-rich organic liquid is stripped with dilute sulfuric acid to obtain a manganese sulfate solution, and the manganese sulfate solution is used to prepare a ternary precursor or manganese tetraoxide;

[0013] The manganese extraction raffinate is countercurrently extracted with a co-extraction organic solvent to obtain an organic solvent loaded with nickel and cobalt and a raffinate;

[0014] The organic solvent loaded with nickel and cobalt is stripped with dilute sulfuric acid to obtain a nickel-cobalt sulfate solution, and the nickel-cobalt sulfate solution is deoiled to prepare a ternary precursor.

[0015] Furthermore, the lithium-ion battery waste is mixed with concentrated sulfuric acid and calcined by reduction calcination at 600-700° C. for 2-3 hours to obtain a calcined material;

[0016] The immersion temperature of the calcined material during water immersion is not greater than 40° C., the immersion time is 2-4 hours, and the liquid-to-solid ratio of the calcined material to water is 10-15:1;

[0017] The pyrolysis temperature of the lithium-rich solution during pyrolysis is 90-100° C., and the pyrolysis time is 4-6 hours.

[0018] Furthermore, the pH of the water-leached residue during leaching in the leaching agent is controlled to be 1.0-2.0, the leaching time is 1-2 hours, and the leaching temperature is 50-70°C.

[0019] Furthermore, the leaching agent is a mixture of ionic liquid, chloride and water in a mass ratio of 2:0.2-1:20-100.

[0020] Further, the ionic liquid is at least one of 1-butyl-3-methylimidazolium hydrogen sulfate, 1-butyl-2,3-dimethylimidazolium bromide, 1-ethyl-3-methylimidazolium hydrogen sulfate, 1-butyl-3-dimethylimidazolium bromide, 1-methylimidazolium hydrogen sulfate, 1-octyl-3-methylimidazolium hydrogen sulfate, and 1-propyl-3-dimethylimidazolium bromide;

[0021] The chloride includes one of sodium chloride, cupric chloride, ferric chloride, sodium chlorite and choline chloride.

[0022] Furthermore, when iron powder or manganese powder is added to the leaching solution to remove copper, the mass of the iron powder or manganese powder added is 1-3 times the total mass of iron and copper in the leaching solution, the reaction temperature is 60-80°C when removing copper, and the reaction time is 1-3h.

[0023] Furthermore, the pH of the solution after adding the alkaline regulator to the copper removal solution is controlled at 4-5.0, the reaction temperature is 60-90° C., the reaction time is 1-3 hours, and the alkaline regulator is lime and / or sodium hydroxide.

[0024] Further, the concentration of dilute sulfuric acid in the stripping manganese-rich organic solution is 100-200 g / L, the O / A ratio is 3-7:1, and the manganese content of the obtained manganese sulfate solution is 100-120 g / L;

[0025] The dilute sulfuric acid concentration of the organic solvent for stripping nickel and cobalt is 300-500 g / L, and the O / A ratio is 4-6:1.

[0026] Furthermore, the preparation of manganese tetraoxide from the manganese sulfate solution comprises the following steps:

[0027] Add 2-5g / L of activated carbon to the manganese sulfate solution to adsorb and remove oil until the oil content in the manganese sulfate solution is less than 0.5mg / L;

[0028] The deoiled manganese sulfate solution is neutralized with ammonia water to a pH of 9.0-12.0, and then filtered and rinsed to obtain a manganese hydroxide suspension;

[0029] The manganese hydroxide suspension is oxidized by passing air at 45°C-85°C until the manganese hydroxide is completely converted into trimanganese tetroxide, and then filtered, rinsed and dried to obtain high-purity trimanganese tetroxide.

[0030] Furthermore, the reaction temperature when the ammonia water is used to neutralize the deoiled manganese sulfate solution is 40°C-60°C, the stirring speed during the reaction is 120r / min-250r / min, and the reaction is kept warm for 0.5h-2h after the ammonia water is added;

[0031] The air flow rate of the manganese hydroxide suspension when passing air for oxidation is 5m 3 / h~15m 3 / h, the stirring speed during oxidation is 120r / min-300r / min, and the oxidation time is 15h-25h.

[0032] The present invention provides a method for recycling waste lithium-ion battery waste, which uses a leaching agent containing ionic liquid and chloride. The leaching agent is green and environmentally friendly and has good reducing and coordination capabilities. It can effectively leach valuable metals such as nickel, cobalt, manganese, copper, and lithium in waste lithium-ion battery waste. The leaching conditions are mild, the leaching time is short, and the leaching effect is good. The leaching rate of nickel, cobalt, manganese, and lithium valuable metals can reach more than 97%. Moreover, when using the leaching agent, no additional reducing agent needs to be added, which can reduce the consumption of auxiliary materials and the recycling cost. At the same time, it can also reduce the introduction of other impurities, greatly improving the quality of the subsequent preparation of ternary precursor products.

[0033] In addition, the present invention provides a method for recycling waste lithium-ion battery waste, which adopts a nickel-cobalt co-extraction method for extraction. Nickel and cobalt do not need to be extracted step by step, and a high-purity nickel-cobalt sulfate solution can be obtained by one-step extraction, which is directly used to prepare a ternary precursor, with low acid and alkali consumption, low cost, short process and high economy.

[0034] At the same time, the method for recycling waste lithium-ion battery waste provided by the present invention is suitable for recycling and processing various complex waste lithium battery wastes. It not only has high recovery efficiency of valuable metal elements such as nickel, cobalt, manganese, copper, and lithium, high processing efficiency, and is green and environmentally friendly, but also is simple to operate, requires simple equipment, has low cost, good economy, and is easy to apply on a large scale. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 A flow chart of a method for recycling waste lithium-ion battery waste provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0036] See also Figure 1 The present invention provides a method for recycling waste lithium-ion battery waste, comprising the following steps:

[0037] Step 1) mixing lithium-ion battery waste with concentrated sulfuric acid and calcining the mixture to obtain a calcined material, leaching the calcined material to obtain a water-leached residue and a lithium-rich solution, and pyrolyzing the lithium-rich solution and centrifuging to obtain a lithium sulfate product.

[0038] Among them, lithium-ion battery waste is powder obtained by disassembling and crushing one or more batteries of lithium cobalt oxide, lithium manganese oxide, and nickel cobalt manganese oxide. The powder contains various impurities such as iron, copper, zinc, aluminum, fluorine, phosphorus, calcium, and magnesium.

[0039] The lithium ion battery waste is added with concentrated sulfuric acid and mixed, and then reduced and calcined at 600-700° C. for 2-3 hours to obtain a calcined material.

[0040] The calcined material is then immersed in water, wherein the liquid-to-solid ratio of the calcined material to water is 10-15:1, the water immersion temperature is not greater than 40° C., and the water immersion time is 2-4 hours, to obtain water leaching slag and lithium-rich solution.

[0041] The lithium-rich solution is then pyrolyzed at a temperature of 90-100° C. for 4-6 hours. Finally, the pyrolyzed lithium-rich solution is centrifuged to obtain a lithium sulfate product.

[0042] Step 2) the water-leached residue is subjected to leaching treatment, wherein the water-leached residue is leached in a leaching agent containing an ionic liquid and chloride, and after the leaching is completed, a leachate and a leached residue are obtained by filtering.

[0043] Specifically, in order to facilitate the leaching of valuable metals and impurity metal elements in the water-leached slag into the leachate, a leaching agent containing ionic liquid and chloride is added to the water-leached slag, the pH of the solution is controlled at 1.0-2.0, the leaching temperature is controlled at 50-70°C, and the leaching time is controlled at 1-2h. The nickel, cobalt, manganese valuable metals and impurity elements such as copper and zinc in the water-leached slag are leached into the solution, and then filtered to obtain the leachate and leached slag.

[0044] The leaching agent is a mixture of ionic liquid, chloride and water in a mass ratio of 2:0.2-1:20-100.

[0045] Among them, ionic liquids are molten salt systems that are liquid at room temperature or near room temperature, composed of anions and cations, with a vapor pressure of almost zero, and are a type of environmentally friendly reagent. Compared with traditional reagents, ionic liquids have low volatility and are non-flammable, which makes them relatively safe and environmentally friendly. The ionic liquids used in the present invention can be purchased from Henan Lihua Pharmaceutical Co., Ltd. or Alfa Aesar Chemical Co., Ltd., and the ionic chemical name is its model.

[0046] As a specific embodiment of the present invention, the ionic liquid is at least one of 1-butyl-3-methylimidazolium hydrogen sulfate, 1-butyl-2,3-dimethylimidazolium bromide, 1-ethyl-3-methylimidazolium hydrogen sulfate, 1-butyl-3-dimethylimidazolium bromide, 1-methylimidazolium hydrogen sulfate, 1-octyl-3-methylimidazolium hydrogen sulfate, and 1-propyl-3-dimethylimidazolium bromide.

[0047] The chloride includes, but is not limited to, one of sodium chloride, cupric chloride, ferric chloride, sodium chlorite, choline chloride (CHCl), and the like.

[0048] Among them, during the leaching process of water leaching residue, the ionic liquid will produce sufficient H + , which can provide an acidic environment for leaching, and is conducive to the leaching of nickel, cobalt, manganese and lithium in the water leaching residue. The chloride ions in the chloride can be used as a good ligand to dissolve the leached metals, and can also produce a synergistic effect with the ionic liquid to further promote the leaching of nickel, cobalt, manganese and lithium in the water leaching residue.

[0049] The present invention adopts a leaching agent containing ionic liquid and chloride, which is green and environmentally friendly and has good reducing properties and coordination capabilities. It can effectively leach valuable metals such as nickel, cobalt, manganese, copper, and lithium in waste lithium-ion battery waste, and the leaching conditions are mild, the leaching time is short, and the leaching effect is good, which can make the leaching rate of nickel, cobalt, manganese, and lithium valuable metals reach more than 97%. Moreover, when using the leaching agent, no additional reducing agent needs to be added, which can reduce the consumption of auxiliary materials, reduce the recycling cost, and reduce the introduction of other impurities, which can greatly improve the quality of the subsequent preparation of ternary precursor products.

[0050] Step 3) adding iron powder and / or manganese powder to the leaching solution to remove copper, and filtering to obtain sponge copper and a solution after copper removal.

[0051] Specifically, iron powder or manganese powder in an amount of 1-3 times the weight of the sum of iron and copper is added to the leaching solution to replace copper, the reaction temperature is 30-80°C, and the reaction time is 1-3h. The following reactions occur in the process:

[0052] Fe+Cu 2+ =Fe 2+ +Cu

[0053] Mn+Cu 2+ =Mn 2+ +Cu

[0054] The reaction mixture is then filtered to obtain sponge copper and copper-removed liquid, and the sponge copper is directly sold.

[0055] Step 4) adding an alkaline regulator to the copper-removed liquid to remove iron and aluminum, and filtering to obtain the iron-removed liquid and iron-aluminum slag.

[0056] Specifically, a certain amount of alkaline regulator, such as lime or sodium hydroxide, is added to the copper-removed solution to adjust the pH of the solution to 4.0-5.0, and then react at 60-90°C for 1-3h to precipitate iron and aluminum in the solution. The following reactions occur during the process:

[0057] Fe 3+ +3OH - =Fe(OH) 3

[0058] Al 3+ +3OH - =Al(OH) 3

[0059] Then the reaction mixture is filtered to obtain the iron and aluminum-free liquid and the Fe(OH) 3 and Al(OH) 3 of iron and aluminum slag.

[0060] Step 5) The liquid after iron and aluminum removal is countercurrently extracted with P204 to obtain a manganese-rich organic liquid and a manganese-extracted residual liquid.

[0061] Specifically, the liquid after iron and aluminum removal is subjected to countercurrent extraction with P204 organic solvent, so that manganese in the liquid after iron and aluminum removal enters into the P204 organic solvent to obtain a manganese-rich organic liquid, and the obtained aqueous phase is the manganese-extracted residual liquid.

[0062] Step 6) The manganese-rich organic liquid is stripped with dilute sulfuric acid to obtain a manganese sulfate solution, and the manganese sulfate solution is used to prepare a ternary precursor or manganese tetraoxide.

[0063] The manganese-rich organic solution is stripped with dilute sulfuric acid at a concentration of 100-200 g / L, with an O / A ratio of 3-7:1, to obtain a manganese sulfate solution with a manganese content of 100-120 g / L.

[0064] Wherein, preparing manganese tetraoxide from manganese sulfate solution comprises the following steps:

[0065] Firstly, the obtained manganese sulfate solution is adsorbed and deoiled by activated carbon, the amount of activated carbon added is 2-5 g / L, and the oil content in the manganese sulfate solution after deoiling is less than 0.5 mg / L.

[0066] Then, the deoiled manganese sulfate solution is neutralized with ammonia water to a pH of 9.0-12.0, and then filtered and rinsed to obtain a manganese hydroxide suspension.

[0067] When ammonia water is used to neutralize the deoiled manganese sulfate solution, the reaction temperature is 40°C to 60°C, the stirring speed is 120r / min to 250r / min, and the reaction is continued for 0.5h to 2h after the addition of ammonia water is completed.

[0068] The obtained manganese hydroxide suspension is then oxidized by passing air at 45°C to 85°C until the manganese hydroxide is completely converted into trimanganese tetroxide, and finally filtered, rinsed and dried to obtain high-purity trimanganese tetroxide.

[0069] Among them, the air flow rate when the manganese hydroxide suspension is oxidized by air is 5m 3 / h~15m 3 / h, the stirring speed during oxidation is controlled at 120r / min~300r / min, and the oxidation time is 15h~25h.

[0070] Step 7) countercurrently extracting the manganese extraction raffinate with the co-extraction organic solvent to obtain the nickel-cobalt loaded organic solvent and the raffinate.

[0071] The present invention adopts a nickel-cobalt co-extraction method for extraction. Nickel and cobalt do not need to be extracted step by step. A high-purity nickel-cobalt sulfate solution can be obtained by one-step extraction, which is directly used to prepare a ternary precursor, with low acid and alkali consumption, low cost, short process and high economy.

[0072] The co-extraction organic solvent used was purchased from Suzhou Bocui Circulation Technology Co., Ltd.

[0073] Step 8) The organic solvent loaded with nickel and cobalt is stripped with dilute sulfuric acid to obtain a nickel-cobalt sulfate solution, and the nickel-cobalt sulfate solution is deoiled to prepare a ternary precursor.

[0074] The concentration of dilute sulfuric acid in the organic solvent used for stripping nickel and cobalt is 300-500 g / L, and the O / A ratio is 4-6:1.

[0075] The deoiling of the nickel cobalt sulfate solution is carried out by using activated carbon to adsorb and deoil the nickel cobalt sulfate solution. The amount of activated carbon added is 2-5 g / L. After deoiling, the oil content in the nickel cobalt sulfate solution is less than 0.5 mg / L.

[0076] The present invention provides a method for recycling waste lithium-ion battery waste, which is suitable for recycling and processing various complex waste lithium battery wastes. It not only has high recovery efficiency of valuable metal elements such as nickel, cobalt, manganese, copper, and lithium, high processing efficiency, and is green and environmentally friendly, but also is simple to operate, requires simple equipment, has low cost, good economy, and is easy to apply on a large scale.

[0077] The following is a detailed description of a method for recycling waste lithium-ion battery waste provided by the present invention through examples and comparative examples.

[0078] Example 1

[0079] A method for recycling waste lithium-ion power battery waste, the specific steps are as follows:

[0080] S1 Acidification and calcination for lithium extraction: Take 300g of material 1 waste battery waste, the specific content is shown in material 1 in Table 1, add 50g of 93% concentrated sulfuric acid and mix, then calcine at 650℃ for 2h to obtain 280g of calcined material, and soak the calcined material in water according to the liquid-solid ratio of 10:1, the soaking temperature is 35℃, and the soaking time is 2h. Filter to obtain 230g of water-leached residue (dry basis) and lithium-rich solution. The lithium-rich solution is pyrolyzed at 95℃ for 5h and then centrifuged to obtain 103g of lithium sulfate, with a lithium yield of 95.68%.

[0081] S2 leaching: add leaching agent to the water leaching residue, control pH=1.5, leaching time 1h, temperature 50℃, ionic liquid, chloride and water in the leaching agent are mixed in a weight ratio of 2:0.3:20, the ionic liquid is 1-butyl-3-methylimidazole hydrogen sulfate, the addition amount is 100g, the chloride is cupric chloride, the addition amount is 15g, 950ml of leaching solution and 20g of leaching residue are obtained by filtration, and the leaching rates of nickel, cobalt and manganese are 98.12%, 98.44% and 97.23% respectively.

[0082] S3 copper removal: 950ml of leaching solution was heated to 65°C, 0.3g of manganese powder was added, and the mixture was reacted for 1h and then filtered to obtain 950ml of copper-removed solution and 0.2g of sponge copper (dry basis).

[0083] S4 iron and aluminum removal: 950 ml of copper removal liquid was heated to 75°C, 140 ml of lime milk (20 wt%) was added, and the reaction was continued for 2 hours, pH value was 4.0, and 1100 ml of iron and aluminum removal liquid and 30 g of iron and aluminum slag (dry basis) were obtained by suction filtration.

[0084] S5 P204 manganese extraction: P204 organic solvent with a saponification rate of 60% (P204 concentration of 30wt%) is subjected to three-stage countercurrent extraction at an O / A ratio of 4:1 to obtain negative manganese organic and manganese extraction residual solution. The negative manganese organic and 200g / L sulfuric acid are stripped at an O / A ratio of 5:1 to obtain 550ml manganese sulfate solution. 3g activated carbon is added to the manganese sulfate solution and stirred to remove oil, thereby obtaining a high-purity manganese sulfate solution. Under the conditions of a reaction temperature of 50°C and a stirring intensity of 200r / min, ammonia water is added dropwise to the high-purity manganese sulfate solution to neutralize it so that the pH value reaches 10.5. After the addition is completed, it is kept warm for 30 minutes, filtered, and rinsed to obtain a manganese hydroxide suspension; the manganese hydroxide suspension is stirred at a temperature of 80°C, a stirring intensity of 180r / min, and an air flow rate of 10m 3 / h for 16 hours. During the reaction, the pH value of the reaction system is controlled to be 7.0-7.4 by adjusting the flow rate of the ammonia water. The manganese tetraoxide slurry obtained by the oxidation reaction is filtered, rinsed, and dried to obtain the final product, manganese tetraoxide.

[0085] S6 nickel-cobalt co-extraction: the manganese extraction residual liquid and the co-extraction organic solvent with a saponification rate of 50% (co-extraction organic solvent concentration 25wt%) are subjected to nine-stage countercurrent extraction at O / A=4:1 to obtain negative nickel-cobalt organic and 1100ml of extract residual liquid, the negative nickel-cobalt organic is stripped with 200g / L sulfuric acid at O / A=5:1 to obtain 550ml of nickel-cobalt sulfate solution, 3g of activated carbon is added to the nickel-cobalt sulfate solution, and stirred to remove oil, so as to obtain a high-purity nickel-cobalt sulfate solution that meets the requirements for the preparation of the ternary precursor; the final calculated nickel yield is 96.46%, and the cobalt yield is 96.12%.

[0086] Table 1 (Unit %)

[0087]

[0088] Example 2

[0089] The difference from Example 1 is that 300 g of material 2 battery waste is taken, and the specific content is shown in material 2 in Table 1, and 48 g of lithium sulfate is produced, with a lithium yield of 95.28%. The final calculated nickel yield is 96.11%, and the cobalt yield is 96.53%.

[0090] Example 3

[0091] The difference from Example 1 is that the ionic liquid, chloride and water in the leaching agent are mixed in a weight ratio of 2:0.5:20, the ionic liquid is 1-methylimidazole hydrogen sulfate, the addition amount is 100g, the chloride is choline chloride, the addition amount is 25g, and 950ml of leaching solution and 15g of leaching residue are obtained by suction filtration. The leaching rates of nickel, cobalt and manganese are 99.52%, 99.04% and 98.72% respectively. The final calculated nickel yield is 97.82%, and the cobalt yield is 97.95%.

[0092] Comparative Example

[0093] The difference from Example 1 is that: S2 leaching: only 100g of ionic liquid and 1L of water were added to the water leaching residue, and other conditions remained unchanged, and the leaching rates of nickel, cobalt, and manganese were 59.43%, 56.33%, and 45.36%, respectively. The final calculated nickel yield was 55.56%, and the cobalt yield was 47.22%.

[0094] By comparing the comparative example with Examples 1-3 of the present invention, it can be seen that Examples 1-3 of the present invention use a leaching agent containing ionic liquid and chloride to leach the water leaching residue, and the leaching rate of nickel, cobalt and manganese in the water leaching residue is high, thereby making the nickel and cobalt yield higher. However, in the comparative example, only a leaching agent containing ionic liquid is used to leach the water leaching residue, and the leaching rate of nickel, cobalt and manganese is low, resulting in a low nickel and cobalt yield.

[0095] Finally, it should be noted that the above specific implementation methods are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A method for recycling waste lithium-ion battery waste, characterized in that: The steps include: The lithium-ion battery waste is mixed with concentrated sulfuric acid and then calcined to obtain a calcined material, the calcined material is soaked in water to obtain a water-leached residue and a lithium-rich solution, and the lithium-rich solution is pyrolyzed and centrifuged to obtain a lithium sulfate product; The water-leached residue is leached in a leaching agent containing an ionic liquid and chloride, and the leaching solution and the leaching residue are filtered; Add iron powder and / or manganese powder to the leaching solution to remove copper, and filter to obtain sponge copper and copper-removed solution; Adding alkaline regulator to the copper-removed liquid to remove iron and aluminum, filtering to obtain the iron-removed liquid and iron-aluminum slag; The liquid after iron and aluminum removal is counter-currently extracted with P204 to obtain manganese-rich organic liquid and manganese-extracted residual liquid; The manganese-rich organic liquid is stripped with dilute sulfuric acid to obtain a manganese sulfate solution, and the manganese sulfate solution is used to prepare a ternary precursor or manganese tetraoxide; The manganese extraction raffinate is countercurrently extracted with a co-extraction organic solvent to obtain an organic solvent loaded with nickel and cobalt and a raffinate; The organic solvent loaded with nickel and cobalt is stripped with dilute sulfuric acid to obtain a nickel-cobalt sulfate solution, and the nickel-cobalt sulfate solution is deoiled to prepare a ternary precursor.

2. The method for recycling waste lithium-ion battery waste according to claim 1, characterized in that: The lithium ion battery waste is mixed with concentrated sulfuric acid and calcined by reduction calcination at 600-700° C. for 2-3 hours to obtain a calcined material; The immersion temperature of the calcined material during water immersion is not greater than 40° C., the immersion time is 2-4 hours, and the liquid-to-solid ratio of the calcined material to water is 10-15:1; The pyrolysis temperature of the lithium-rich solution during pyrolysis is 90-100° C., and the pyrolysis time is 4-6 hours.

3. The method for recycling waste lithium-ion battery waste according to claim 1, characterized in that: The pH of the water-leached residue during leaching in the leaching agent is controlled to be 1.0-2.0, the leaching time is 1-2 hours, and the leaching temperature is 50-70°C.

4. The method for recycling waste lithium-ion battery waste according to claim 3, characterized in that: The leaching agent is prepared by mixing ionic liquid, chloride and water in a mass ratio of 2:0.2-1:20-100.

5. The method for recycling waste lithium-ion battery waste according to claim 4, characterized in that: The ionic liquid is at least one of 1-butyl-3-methylimidazolium hydrogen sulfate, 1-butyl-2,3-dimethylimidazolium bromide, 1-ethyl-3-methylimidazolium hydrogen sulfate, 1-butyl-3-dimethylimidazolium bromide, 1-methylimidazolium hydrogen sulfate, 1-octyl-3-methylimidazolium hydrogen sulfate, and 1-propyl-3-dimethylimidazolium bromide; The chloride includes one of sodium chloride, cupric chloride, ferric chloride, sodium chlorite and choline chloride.

6. The method for recycling waste lithium-ion battery waste according to claim 1, characterized in that: When adding iron powder or manganese powder to the leaching solution to remove copper, the mass of the iron powder or manganese powder added is 1-3 times the total mass of iron and copper in the leaching solution. When removing copper, the reaction temperature is 60-80° C. and the reaction time is 1-3 hours.

7. The method for recycling waste lithium-ion battery waste according to claim 1, characterized in that: The pH of the solution after adding the alkaline regulator to the copper removal solution is controlled at 4.0-5.0, the reaction temperature is 60-90° C., and the reaction time is 1-3 hours. The alkaline regulator is lime and / or sodium hydroxide.

8. The method for recycling waste lithium-ion battery waste according to claim 1, characterized in that: The dilute sulfuric acid concentration of the stripping manganese-rich organic solution is 100-200 g / L, the O / A ratio is 3-7:1, and the manganese content of the obtained manganese sulfate solution is 100-120 g / L; The dilute sulfuric acid concentration of the organic solvent for stripping nickel and cobalt is 300-500 g / L, and the O / A ratio is 4-6:

1.

9. The method for recycling waste lithium-ion battery waste according to claim 1, characterized in that: The preparation of manganese tetraoxide from manganese sulfate solution comprises the following steps: Add 2-5g / L of activated carbon to the manganese sulfate solution to adsorb and remove oil until the oil content in the manganese sulfate solution is less than 0.5mg / L; The deoiled manganese sulfate solution is neutralized with ammonia water to a pH of 9.0-12.0, and then filtered and rinsed to obtain a manganese hydroxide suspension; The manganese hydroxide suspension is oxidized by passing air at 45°C-85°C until the manganese hydroxide is completely converted into trimanganese tetroxide, and then filtered, rinsed and dried to obtain high-purity trimanganese tetroxide.

10. The method for recycling waste lithium-ion battery waste according to claim 9, characterized in that: The reaction temperature when the ammonia water is used to neutralize the deoiled manganese sulfate solution is 40°C-60°C, the stirring speed during the reaction is 120r / min-250r / min, and the reaction is kept warm for 0.5h-2h after the ammonia water is added; The air flow rate of the manganese hydroxide suspension when passing air for oxidation is 5m 3 / h-15m 3 / h, stirring speed during oxidation is 120r / min-300r / min, and oxidation time is 15h-25h.

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