Method for full-chain integrated recycling of spent ternary battery powder

Abstract

Disclosed in the present disclosure is a method for full-chain integrated recycling of spent ternary battery powder. Iron-aluminum slag and spent ternary battery powder undergo joint roasting, and then the roasted slag undergoes water leaching for lithium extraction. In one aspect, lithium element is converted by using natroalunite and natrojarosite in the roasted slag, and in the other aspect, a trace amount of nickel, cobalt and manganese residuals in the roasted slag can be recycled together with nickel, cobalt and manganese in the spent ternary battery powder. In embodiments, pyrometallurgy and hydrometallurgy are jointly used, which is conductive to improving the metal recovery rate, reducing the auxiliary reagent consumption cost, simplifying the technological process, and improving the production efficiency.

Description

Full-chain integrated method for recycling waste ternary battery powder Technical Field

[0001] The present disclosure relates to the technical field of waste ternary battery recycling and processing, and in particular to a full-chain integrated method for recycling waste ternary battery powder. Background Art

[0002] With the rapid development of my country's new energy vehicle industry in recent years, demand for power batteries has skyrocketed. Ternary power batteries, with their advantages such as high energy density, high voltage, and excellent cycle performance, are widely used in the new energy vehicle industry, resulting in a large amount of waste ternary batteries. Waste ternary batteries contain significant amounts of valuable metals such as nickel, cobalt, manganese, and lithium, at levels far higher than those found in ore. If not recycled, they would not only result in a significant waste of resources but also pollute the environment. Therefore, the valuable metal resources contained in waste ternary batteries are extremely valuable for recycling.

[0003] Currently, the main industrial method for recycling lithium batteries is a wet leaching process, where used lithium batteries are acid-leached. After acid leaching, they undergo impurity removal and extraction steps to recover nickel, cobalt, manganese, and lithium. However, ferroaluminum slag, the primary product of the impurity removal step in wet battery recycling, contains large amounts of iron and aluminum compounds, as well as residual amounts of nickel, cobalt, manganese, and lithium. Currently, ferroaluminum slag is primarily treated as hazardous solid waste, resulting in wasteful resources and unnecessary production costs. Therefore, developing a new method for the comprehensive recovery of metal elements from ferroaluminum slag is of great significance.

[0004] Summary of the Invention

[0005] The purpose of the present disclosure is to provide a full-chain integrated method for recycling waste ternary battery powder, which can give priority to recycling lithium in waste ternary battery powder, which is conducive to the separate utilization of lithium and nickel, cobalt and manganese.

[0006] The present disclosure is achieved as follows:

[0007] In a first aspect, the present disclosure provides a method for recycling waste ternary battery powder, comprising:

[0008] calcining, calcining the first mixed material containing waste ternary battery powder and iron-aluminum slag in an oxygen-free state to obtain a first calcined material;

[0009] Lithium is extracted by water, and the first roasted material is mixed with water to perform a first leaching and solid-liquid separation to obtain a first water-leached residue and a lithium-rich solution.

[0010] In some embodiments, the mass ratio of waste ternary battery powder and iron-aluminum slag in the first mixture is (5-20):1.

[0011] In some embodiments, the calcination temperature of the oxygen-free calcination step is 300° C. to 550° C., and the calcination time is 1 hour to 3 hours.

[0012] In some embodiments, the main components of the ferroaluminum slag include 9.0 wt% to 9.5 wt% of datrol aluminum sulfate and 27 wt% to 28 wt% of datrol aluminum sulfate.

[0013] In some embodiments, the mass ratio of waste ternary battery powder and iron-aluminum slag in the first mixture is (8-10):1.

[0014] In some embodiments, the first mixture contains 18 wt% to 20 wt% Ni, 3.5 wt% to 4.0 wt% Co, 9.5 wt% to 10.0 wt% Mn, 4.0 wt% to 4.5 wt% Li, 0.6% to 0.8% Al, and 2.5% to 2.7 wt% Fe.

[0015] In some embodiments, the first roasted material is mixed with water at a liquid-to-solid ratio of 3 mL / g to 9 mL / g for the first leaching.

[0016] In some embodiments, the temperature of the water leaching lithium step is 30° C. to 90° C., and the time is 0.5 h to 3 h.

[0017] In some embodiments, the lithium-rich solution has a Ni concentration of less than 0.0015 g / L, a Co concentration of less than 0.0015 g / L, a Mn concentration of less than 0.01 g / L, a Li concentration of greater than 7.5 g / L, an Al concentration of less than 0.0025 g / L, and a Fe concentration of less than 0.004 g / L.

[0018] In some embodiments, further comprising:

[0019] Mixing the first water-leached residue with ferrous sulfate and performing acid reduction roasting to obtain a second roasted material;

[0020] The second roasted material is mixed with water to carry out a second leaching and solid-liquid separation to obtain graphite slag and nickel-cobalt-manganese leaching solution.

[0021] In some embodiments, the ratio of the total molar amount of nickel, cobalt and manganese in the first water-leached residue to the molar amount of ferrous sulfate is (0.5-2.5):1.

[0022] In some embodiments, the acid reduction roasting is performed at a temperature of 300° C. to 900° C., and for a time of 1 hour to 3 hours.

[0023] In some embodiments, the second calcined material is mixed with water at a liquid-to-solid ratio of 2 mL / g to 6 mL / g.

[0024] In some embodiments, the second leaching is carried out at a temperature of 30° C. to 90° C. for a time of 0.5 h to 3 h.

[0025] In some embodiments, the pH of the nickel-cobalt-manganese leaching solution is adjusted to 4.0-6.0 to precipitate iron and aluminum, and then solid-liquid separation is performed to obtain a decontaminated nickel-cobalt-manganese leaching solution and iron-aluminum slag.

[0026] In some embodiments, the temperature of the iron and aluminum precipitation step is 90°C to 95°C.

[0027] In some embodiments, the Ni concentration in the impurity-removed nickel-cobalt-manganese leaching solution is greater than 19.5 g / L, the Co concentration is greater than 3.2 g / L, the Mn concentration is greater than 9.1 g / L, the Li concentration is less than 0.14 g / L, the Al concentration is less than 0.002 g / L, and the Fe concentration is less than 0.0025 g / L.

[0028] The present disclosure has the following beneficial effects:

[0029] The ferroaluminum slag disclosed herein is derived from the primary product of the impurity removal process during wet-process battery recycling. The ferroaluminum slag is co-roasted with spent ternary battery powder. This allows the conversion of lithium using the sodium aluminum sulfate and sodium ferroaluminum sulfate contained in the ferroaluminum slag. Furthermore, trace amounts of nickel, cobalt, and manganese remaining in the ferroaluminum slag can be recycled along with the nickel, cobalt, and manganese in the spent ternary battery powder. This embodiment utilizes a combination of pyrometallurgical and hydrometallurgical processes, which is beneficial for improving lithium recovery, reducing the cost of auxiliary materials and reagents, simplifying the process, and improving production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present disclosure and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0031] FIG1 is a flow chart of the present disclosure;

[0032] FIG2 is a flow chart of embodiment 1 of the present disclosure. DETAILED DESCRIPTION

[0033] To make the purpose, technical solutions, and advantages of the embodiments of the present disclosure more clear, the technical solutions in the embodiments of the present disclosure are described clearly and completely below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer were followed. Reagents or instruments used where the manufacturer is not specified are conventional products that can be purchased commercially.

[0034] One embodiment of the present disclosure provides a method for recycling waste ternary battery powder, as shown in FIG1 , comprising:

[0035] calcining, calcining the first mixed material containing waste ternary battery powder and iron-aluminum slag in an oxygen-free state to obtain a first calcined material;

[0036] Lithium is extracted by water, and the first roasted material is mixed with water to perform a first leaching and solid-liquid separation to obtain a first water-leached residue and a lithium-rich solution.

[0037] The spent ternary battery powder in this embodiment is typically obtained by fully discharging spent lithium batteries in a saturated sodium chloride solution, drying them in an oven, and then disassembling them. It contains ternary materials, graphite, some electrode plates, and residual electrolyte. The iron-aluminum slag in this embodiment is derived from the main products of the impurity removal process during wet battery recycling. It contains naoite aluminum sulfate and naoite iron sulfate, which react with ternary materials.

[0038] This embodiment mainly recovers the lithium element in the waste ternary battery powder. Specifically, during the oxygen-free roasting process, the lithium element in the waste ternary battery powder undergoes the following reaction and is converted into water-soluble lithium sulfate, while other valuable metal elements such as nickel, cobalt, and manganese still exist in the form of high-valent oxides, allowing the lithium element to be preferentially dissolved from the first roasting material.

[0039] 2LiNi x Co y Mn 1-x-y O2+Na2Fe6(SO4)4(OH) 12 →Li2SO4+Fe2(SO4)3+4Fe(OH)3+2NaNi x Co y Mn 1-x -y O2

[0040] 2LiNi x Co y Mn 1-x-y O2+Na2Al6(SO4)4(OH) 12 →Li2SO4+Al2(SO4)3+4Al(OH)3+2NaNi x Co y Mn 1-x -y O2

[0041] The ferroaluminum slag disclosed herein is derived from the primary product of the impurity removal process during wet-process battery recycling. The ferroaluminum slag is co-roasted with spent ternary battery powder. This allows the conversion of lithium using the sodium aluminum sulfate and sodium ferroaluminum sulfate present in the ferroaluminum slag. Furthermore, trace amounts of nickel, cobalt, and manganese remaining in the ferroaluminum slag can be recycled along with the nickel, cobalt, and manganese present in the spent ternary battery powder. This embodiment utilizes a combination of pyrometallurgical and hydrometallurgical processes, which improves lithium recovery, reduces the cost of auxiliary materials and reagents, simplifies the process flow, and enhances production efficiency.

[0042] In some embodiments, the mass ratio of waste ternary battery powder and iron-aluminum slag in the first mixture is (5-20):1, specifically 5:1, 10:1, 15:1, 20:1 or any value between (5-20):1.

[0043] In this embodiment, the waste ternary battery powder and the iron-aluminum slag do not react strictly according to the stoichiometric ratio. Since the iron-aluminum slag contains other components in addition to natrona aluminum sulfate and natrona ferrosulfate, these other components may also play a certain role in the conversion of lithium into soluble lithium salts.

[0044] In some embodiments, the calcination temperature of the oxygen-free calcination step is 300°C to 550°C, specifically 300°C, 350°C, 400°C, 450°C, 500°C, 550°C or any value between 300°C and 550°C, and the calcination time is 1h to 3h, specifically 1h, 1.5h, 2h, 2.5h, 3h or any value between 1h and 3h.

[0045] The first mixed material is roasted at 300°C to 550°C. The sodium aluminum sulfate and sodium iron sulfate in the first mixed material will decompose into sodium sulfate, iron sulfate and aluminum sulfate. The waste ternary material mainly reacts with sodium sulfate to form lithium sulfate. The sulfate ions in the iron sulfate and aluminum sulfate have difficulty combining with the lithium in the ternary material, and only a small part can be used for the conversion of lithium elements. Specifically, when the temperature of the oxygen-free roasting step is low, the ternary material and the iron-aluminum slag are difficult to fully react, resulting in a low lithium leaching rate in the subsequent water leaching step of lithium extraction. However, when the temperature of the oxygen-free roasting step is higher, the nickel in the ternary material will be converted into nickel element. The nickel element is not easily converted into a soluble salt in the subsequent treatment. Therefore, the temperature of the oxygen-free roasting should not be too high.

[0046] In some embodiments, the main components of the ferroaluminum slag include 9.0 wt% to 9.5 wt% of datrol aluminum sulfate and 27 wt% to 28 wt% of datrol aluminum sulfate.

[0047] In some embodiments, the mass ratio of waste ternary battery powder and iron-aluminum slag in the first mixture is (8-10):1, and the lithium leaching rate is higher within this range.

[0048] In some embodiments, the first mixture contains 18 wt% to 20 wt% Ni, 3.5 wt% to 4.0 wt% Co, 9.5 wt% to 10.0 wt% Mn, 4.0 wt% to 4.5 wt% Li, 0.6% to 0.8% Al, and 2.5% to 2.7 wt% Fe.

[0049] In some embodiments, the first roasted material is mixed with water at a liquid-to-solid ratio of 3 mL / g to 9 mL / g for the first leaching. Specifically, the liquid-to-solid ratio can be 3 mL / g, 4 mL / g, 5 mL / g, 6 mL / g, 7 mL / g, 8 mL / g, 9 mL / g or any value between 3 mL / g and 9 mL / g.

[0050] Generally speaking, the larger the liquid-to-solid ratio, the faster and more fully the soluble components in the solid can be dissolved. However, if the liquid-to-solid ratio is too large, the subsequent separation and recovery of the soluble components will be more difficult. Therefore, the liquid-to-solid ratio in the first leaching step needs to be controlled within a reasonable range.

[0051] In some embodiments, the temperature of the water leaching step for lithium extraction is 30° C. to 90° C., specifically 30° C., 40° C., 50° C., 60° C., 70° C., 80° C., 90° C., or any value between 30° C. and 90° C., and the time is 0.5 h to 3 h, specifically 0.5 h, 1 h, 1.5 h, 2 h, 2.5 h, 3 h, or any value between 0.5 h and 3 h. Within this range, it is beneficial to increase the leaching efficiency and leaching rate of water-soluble lithium salts.

[0052] In some embodiments, the lithium-rich solution has a Ni concentration of less than 0.0015 g / L, a Co concentration of less than 0.0015 g / L, a Mn concentration of less than 0.01 g / L, a Li concentration of greater than 7.5 g / L, an Al concentration of less than 0.0025 g / L, and a Fe concentration of less than 0.004 g / L, and the contents of impurities such as nickel, cobalt, manganese, iron, and aluminum are relatively low.

[0053] In some embodiments, further comprising:

[0054] Mixing the first water-leached residue with ferrous sulfate and performing acid reduction roasting to obtain a second roasted material;

[0055] The second roasted material is mixed with water to carry out a second leaching and solid-liquid separation to obtain graphite slag and nickel-cobalt-manganese leaching solution.

[0056] Ferrous sulfate with a certain reducing property is used to carry out acid reduction roasting with the first water leaching residue, which involves the following reaction, reducing nickel, cobalt and manganese into water-soluble divalent sulfates, which facilitates the subsequent water leaching and separation of nickel, cobalt and manganese elements in the roasting material.

[0057] 2NaNi xCo y Mn 1-x-y O2+3FeSO4=2xNiSO4+2yCoSO4+2(1-xy)MnSO4+Fe3O4+Na2SO4

[0058] The main component of the graphite slag after separation of nickel, cobalt and manganese is graphite, and it also contains some aluminum and iron.

[0059] In some embodiments, the ratio of the total molar amount of nickel, cobalt and manganese in the first water-leached residue to the molar amount of ferrous sulfate is (0.5-2.5):1, specifically 0.5:1, 1:1, 1.5:1, 2:1, 2.5:1 or any value between (0.5-2.5):1.

[0060] Excessive ferrous sulfate will lead to its inability to fully react, waste raw materials, and be unfavorable for the recycling of subsequent components. Too little ferrous sulfate will prevent the complete conversion of nickel, cobalt and manganese, which will reduce the leaching rate of nickel, cobalt and manganese.

[0061] In some embodiments, the calcination temperature of the acidification reduction calcination is 300°C to 900°C, specifically 300°C, 400°C, 500°C, 600°C, 700°C, 800°C, 900°C or any value between 300°C and 900°C, and the calcination time is 1h to 3h, specifically 1h, 1.5h, 2h, 2.5h, 3h or any value between 1h and 3h.

[0062] Specifically, when the temperature of the acid reduction roasting is low, the nickel, cobalt and manganese in the first water leaching residue are difficult to fully react with ferrous sulfate, resulting in a low nickel, cobalt and manganese leaching rate in the subsequent water leaching step; however, when the temperature of the acid reduction roasting is higher, it will also lead to problems of excessive energy consumption and higher equipment requirements.

[0063] Generally, both the oxygen-free calcination and the acid reduction calcination in the present disclosure require an oxygen-free environment, and argon, nitrogen, etc. may be introduced during the specific operation.

[0064] In some embodiments, the second calcined material is mixed with water at a liquid-to-solid ratio of 2 mL / g to 6 mL / g. Specifically, the liquid-to-solid ratio can be 2 mL / g, 3 mL / g, 4 mL / g, 5 mL / g, 6 mL / g, or any value between 2 mL / g and 6 mL / g.

[0065] Generally speaking, the larger the liquid-to-solid ratio, the faster and more fully the soluble components in the solid can be dissolved. However, if the liquid-to-solid ratio is too large, the subsequent separation and recovery of the soluble components will be more difficult. Therefore, the liquid-to-solid ratio in the second leaching step needs to be controlled within a reasonable range.

[0066] In some embodiments, the second leaching temperature is 30°C to 90°C, specifically 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, or any value between 30°C and 90°C, and the time is 0.5h to 3h, specifically 0.5h, 1h, 1.5h, 2h, 2.5h, 3h, or any value between 0.5h and 3h. Within this range, it is beneficial to increase the leaching efficiency and leaching rate of water-soluble nickel salts, cobalt salts, and manganese salts.

[0067] In some embodiments, the pH of the nickel-cobalt-manganese leaching solution is adjusted to 4.0-6.0 to precipitate iron and aluminum, followed by solid-liquid separation to obtain a decontaminated nickel-cobalt-manganese leaching solution and iron-aluminum slag. Specifically, the pH can be 4.0, 4.5, 5.0, 5.5, 6.0, or any value between 4.0 and 6.0. Within this range, sodium sulfate in the solution reacts with iron and aluminum by heating, forming complexes of naoite and naoite precipitates, thereby separating the iron and aluminum from the nickel-cobalt-manganese leaching solution.

[0068] In some embodiments, the temperature of the iron and aluminum precipitation step is 90°C to 95°C, and specifically the pH can be 90°C, 91°C, 92°C, 93°C, 94°C, 95°C or any value between 90°C and 95°C. Heating is beneficial to the efficiency of iron and aluminum complexation to synthesize natto iron sulfate and natto aluminum sulfate.

[0069] In some embodiments, the Ni concentration in the impurity-removed nickel-cobalt-manganese leaching solution is greater than 19.5 g / L, the Co concentration is greater than 3.2 g / L, the Mn concentration is greater than 9.1 g / L, the Li concentration is less than 0.14 g / L, the Al concentration is less than 0.002 g / L, and the Fe concentration is less than 0.0025 g / L, and the concentrations of lithium, aluminum, and iron are all relatively low.

[0070] The features and properties of the present disclosure are further described in detail below in conjunction with the examples, wherein the element contents in the mixture 1 and the graphite slag are all expressed in mass fractions.

[0071] Example 1:

[0072] This embodiment provides a method for recycling waste ternary battery powder, as shown in FIG2 , which specifically includes the following steps:

[0073] (1) Combined roasting. Waste ternary battery powder and iron-aluminum slag are mixed in a mass ratio of 10:1 to obtain mixed material 1. Nitrogen is introduced into the mixed material 1 and roasted at 450°C in an oxygen-free environment for 2 hours to obtain roasted material 2.

[0074] (2) Lithium extraction by water leaching: The roasted material 2 was mixed with water for the first leaching, with a liquid-to-solid ratio of 5:1 mL / g, a temperature of 50°C, and a time of 2 h. After leaching, the leached residue 3 and the lithium-rich solution 1 were obtained by filtration.

[0075] (3) Acidification and reduction roasting. Ferrous sulfate and water-leached residue 3 were mixed evenly and roasted. The ratio of the amount of ferrous sulfate added to the amount of Ni+Co+Mn metal in the water-leached residue 3 was 1.2:1. The mixture was roasted at 480°C under nitrogen for 2 hours. The roasted material 4 was obtained.

[0076] (4) Water Leaching of Nickel, Cobalt and Manganese: The roasted material 4 was subjected to a second water leaching, with a liquid-to-solid ratio of 5:1 mL / g, a temperature of 60°C, and a time of 2 h. The nickel, cobalt and manganese leaching solution 2 and graphite slag 5 were separated by filtration.

[0077] (5) Impurity removal. The nickel-cobalt-manganese leaching solution 2 is maintained at 95°C, and sodium hydroxide is added to adjust the solution pH to 5.5 to remove iron and aluminum impurities. After filtration and separation, pure nickel-cobalt-manganese solution 3 and iron-aluminum slag 6 are obtained. The iron-aluminum slag 6 can be used as a mixing ingredient for waste ternary battery powder.

[0078] Passed ICP element test,

[0079] Mixture 1: Ni content 19.0183%, Co content 3.7245%, Mn content 9.9731%, Li content 4.1802%, Al content 0.6354%, Fe content 2.5519%;

[0080] Lithium-rich solution 1: Ni concentration 0.0001 g / L, Co concentration 0.0007 g / L, Mn concentration 0.0010 g / L, Li concentration 8.8532 g / L, Al concentration 0.0008 g / L, Fe concentration 0.0006 g / L;

[0081] Graphite slag 4: Ni content 0.1775%, Co content 0.0734%, Mn content 0.2611%, Li content 0.0001%, Al content 1.1746%, Fe content 4.9235%;

[0082] In the pure nickel-cobalt-manganese solution 3, the Ni concentration is 20.4625 g / L, the Co concentration is 3.9571 g / L, the Mn concentration is 9.4461 g / L, the Li concentration is 0.1152 g / L, the Al concentration is 0.0006 g / L, and the Fe concentration is 0.0008 g / L;

[0083] Through the above process, Ni leaching rate of 99.64%, Co leaching rate of 99.23%, Mn leaching rate of 98.75%, and Li leaching rate of 99.84% can be obtained.

[0084] Example 2:

[0085] This embodiment provides a method for recycling waste ternary battery powder, which specifically includes the following steps:

[0086] (1) Combined roasting. Waste ternary battery powder and iron-aluminum slag are mixed in a mass ratio of 8:1 to obtain mixed material 1. Nitrogen is introduced into the mixed material 1 and roasted at 450°C in an oxygen-free environment for 2 hours to obtain roasted material 2.

[0087] (2) Lithium extraction by water leaching: The roasted material 2 was mixed with water for the first leaching, with a liquid-to-solid ratio of 5:1 mL / g, a temperature of 50°C, and a time of 2 h. After leaching, the leached residue 3 and the lithium-rich solution 1 were obtained by filtration.

[0088] (3) Acidification and reduction roasting. Ferrous sulfate and water-leached residue 3 were mixed evenly and roasted. The ratio of the amount of ferrous sulfate added to the amount of Ni+Co+Mn metal in the water-leached residue 3 was 1.2:1. The mixture was roasted at 480°C under nitrogen for 2 hours. The roasted material 4 was obtained.

[0089] (4) Water Leaching of Nickel, Cobalt and Manganese: The roasted material 4 was subjected to a second water leaching, with a liquid-to-solid ratio of 5:1 mL / g, a temperature of 60°C, and a time of 2 h. The nickel, cobalt and manganese leaching solution 2 and graphite slag 5 were separated by filtration.

[0090] (5) Impurity removal. The nickel-cobalt-manganese leaching solution 2 is maintained at 95°C, and sodium hydroxide is added to adjust the solution pH to 5.5 to remove iron and aluminum impurities. After filtration and separation, pure nickel-cobalt-manganese solution 3 and iron-aluminum slag 6 are obtained. The iron-aluminum slag 6 can be used as a mixing ingredient for waste ternary battery powder.

[0091] Passed ICP element test,

[0092] Mixture 1: Ni content 18.9116%, Co content 3.6638%, Mn content 9.759%, Li content 4.0962%, Al content 0.7192%, Fe content 2.6868%;

[0093] Lithium-rich solution 1: Ni concentration 0.0012 g / L, Co concentration 0.0011 g / L, Mn concentration 0.0092 g / L, Li concentration 7.6461 g / L, Al concentration 0.0021 g / L, Fe concentration 0.0038 g / L;

[0094] Graphite slag 4: Ni content 0.1784%, Co content 0.11385%, Mn content 0.3162%, Li content 0.0001%, Al content 1.2049%, Fe content 4.9906%;

[0095] In the pure nickel-cobalt-manganese solution 3, the Ni concentration is 20.2257 g / L, the Co concentration is 3.5549 g / L, the Mn concentration is 9.1454 g / L, the Li concentration is 0.1372 g / L, the Al concentration is 0.0017 g / L, and the Fe concentration is 0.0022 g / L;

[0096] Through the above process, Ni leaching rate of 99.54%, Co leaching rate of 99.17%, Mn leaching rate of 98.34%, and Li leaching rate of 99.72% can be obtained.

[0097] Example 3:

[0098] This embodiment provides a method for recycling waste ternary battery powder, which specifically includes the following steps:

[0099] (1) Combined roasting. Waste ternary battery powder and iron-aluminum slag are mixed in a mass ratio of 10:1 to obtain mixed material 1. Nitrogen is introduced into the mixed material 1 and roasted at 450°C in an oxygen-free environment for 2 hours to obtain roasted material 2.

[0100] (2) Lithium extraction by water leaching: The roasted material 2 was mixed with water for the first leaching, with a liquid-to-solid ratio of 5:1 mL / g, a temperature of 50°C, and a time of 2 h. After leaching, the leached residue 3 and the lithium-rich solution 1 were obtained by filtration.

[0101] (3) Acidification and reduction roasting. Mix ferrous sulfate and water-leached residue 3 evenly and roast them. The ratio of the amount of ferrous sulfate added to the amount of Ni+Co+Mn metal in the water-leached residue 3 is 1:1. Roast at 480°C under nitrogen for 2 hours to obtain roasted material 4.

[0102] (4) Water Leaching of Nickel, Cobalt and Manganese: The roasted material 4 was subjected to a second water leaching, with a liquid-to-solid ratio of 5:1 mL / g, a temperature of 60°C, and a time of 2 h. The nickel, cobalt and manganese leaching solution 2 and graphite slag 5 were separated by filtration.

[0103] (5) Impurity removal. The nickel-cobalt-manganese leaching solution 2 is maintained at 95°C, and sodium hydroxide is added to adjust the solution pH to 5.5 to remove iron and aluminum impurities. After filtration and separation, pure nickel-cobalt-manganese solution 3 and iron-aluminum slag 6 are obtained. The iron-aluminum slag 6 can be used as a mixing ingredient for waste ternary battery powder.

[0104] Passed ICP element test,

[0105] Mixture 1: Ni content 19.0516%, Co content 3.7712%, Mn content 9.9184%, Li content 4.1615%, Al content 0.6354%, Fe content 2.5519%;

[0106] Lithium-rich solution 1: Ni concentration 0.0009 g / L, Co concentration 0.00012 g / L, Mn concentration 0.0018 g / L, Li concentration 8.8064 g / L, Al concentration 0.0007 g / L, Fe concentration 0.0009 g / L;

[0107] Graphite slag 4: Ni content 0.2045%, Co content 0.11582%, Mn content 0.2938%, Li content 0.0001%, Al content 1.2259%, Fe content 5.0725%;

[0108] In the pure nickel-cobalt-manganese solution 3, the Ni concentration is 19.7422 g / L, the Co concentration is 3.2162 g / L, the Mn concentration is 9.3602 g / L, the Li concentration is 0.1280 g / L, the Al concentration is 0.0013 g / L, and the Fe concentration is 0.0021 g / L;

[0109] Through the above process, a Ni leaching rate of 98.38%, a Co leaching rate of 97.75%, a Mn leaching rate of 95.74%, and a Li leaching rate of 99.72% can be obtained.

[0110] Example 4

[0111] This embodiment provides a method for recycling waste ternary battery powder, which differs from Example 1 only in that in step (1), the waste ternary battery powder and iron-aluminum slag are mixed in a mass ratio of 5:1.

[0112] Passed ICP element test,

[0113] Mixture 1: Ni content 17.8384%, Co content 3.0516%, Mn content 9.1942%, Li content 3.9688%, Al content 0.80422%, Fe content 2.7615%;

[0114] Lithium-rich solution 1: Ni concentration 0.0009 g / L, Co concentration 0.0015 g / L, Mn concentration 0.0137 g / L, Li concentration 7.1064 g / L, Al concentration 0.0018 g / L, Fe concentration 0.0026 g / L;

[0115] Graphite slag 4: Ni content 0.1955%, Co content 0.1542%, Mn content 0.3716%, Li content 0.0018%, Al content 1.3648%, Fe content 5.1026%;

[0116] In the pure nickel-cobalt-manganese solution 3, the Ni concentration is 19.725 g / L, the Co concentration is 3.1011 g / L, the Mn concentration is 8.6428 g / L, the Li concentration is 0.15532 g / L, the Al concentration is 0.0023 g / L, and the Fe concentration is 0.0055 g / L;

[0117] Through the above process, Ni leaching rate of 99.01%, Co leaching rate of 98.75%, Mn leaching rate of 96.26%, and Li leaching rate of 99.25% can be obtained.

[0118] Example 5

[0119] This embodiment provides a method for recycling waste ternary battery powder, which differs from embodiment 1 only in that the mixed material 1 in step (1) is roasted at a temperature of 580° C. in the absence of oxygen for 2 hours.

[0120] Passed ICP element test,

[0121] Mixture 1: Ni content 19.1105%, Co content 3.6854%, Mn content 9.9154%, Li content 4.1601%, Al content 0.6545%, Fe content 2.5621%;

[0122] Lithium-rich solution 1: Ni concentration 0.0004 g / L, Co concentration 0.0010 g / L, Mn concentration 0.0017 g / L, Li concentration 8.2646 g / L, Al concentration 0.0010 g / L, Fe concentration 0.0009 g / L;

[0123] Graphite slag 4: Ni content 1.0775%, Co content 0.8268%, Mn content 0.6799%, Li content 0.0007%, Al content 1.0128%, Fe content 4.635%;

[0124] In the pure nickel-cobalt-manganese solution 3, the Ni concentration is 18.465 g / L, the Co concentration is 3.185 g / L, the Mn concentration is 8.9521 g / L, the Li concentration is 0.1364 g / L, the Al concentration is 0.0017 g / L, and the Fe concentration is 0.0026 g / L;

[0125] Through the above process, Ni leaching rate of 97.35%, Co leaching rate of 97.62%, Mn leaching rate of 96.45%, and Li leaching rate of 99.02% can be obtained.

[0126] Example 6

[0127] This embodiment provides a method for recycling waste ternary battery powder, which differs from Example 1 only in that the ratio of the amount of ferrous sulfate added in step (3) to the amount of Ni+Co+Mn metal substance in the water-leached residue 3 is 2.5:1.

[0128] Passed ICP element test,

[0129] Mixture 1: Ni content 19.0245%, Co content 3.687%, Mn content 9.9163%, Li content 4.2095%, Al content 0.6565%, Fe content 2.5162%;

[0130] Lithium-rich solution 1: Ni concentration 0.0005 g / L, Co concentration 0.0009 g / L, Mn concentration 0.0014 g / L, Li concentration 8.7761 g / L, Al concentration 0.0011 g / L, Fe concentration 0.0009 g / L;

[0131] Graphite slag 4: Ni content 0.1742%, Co content 0.0683%, Mn content 0.2461%, Li content 0.0001%, Al content 1.1562%, Fe content 5.1342%;

[0132] In the pure nickel-cobalt-manganese solution 3, the Ni concentration is 20.0125 g / L, the Co concentration is 3.8265 g / L, the Mn concentration is 9.4535 g / L, the Li concentration is 0.1225 g / L, the Al concentration is 0.0010 g / L, and the Fe concentration is 0.0037 g / L;

[0133] Through the above process, a Ni leaching rate of 99.35%, a Co leaching rate of 99.08%, a Mn leaching rate of 98.16%, and a Li leaching rate of 99.64% can be obtained.

[0134] Example 7

[0135] This embodiment provides a method for recycling waste ternary battery powder, which differs from Example 1 only in that the roasting temperature in step (3) is 700°C.

[0136] Passed ICP element test,

[0137] Mixture 1: Ni content 19.0095%, Co content 3.6752%, Mn content 9.9561%, Li content 4.1625%, Al content 0.6185%, Fe content 2.4876%;

[0138] Lithium-rich solution 1: Ni concentration 0.0001 g / L, Co concentration 0.0008 g / L, Mn concentration 0.0009 g / L, Li concentration 8.6334 g / L, Al concentration 0.0019 g / L, Fe concentration 0.0008 g / L;

[0139] Graphite slag 4: Ni content 2.6485%, Co content 1.354%, Mn content 1.0751%, Li content 0.0015%, Al content 1.5265%, Fe content 5.1602%;

[0140] In the pure nickel-cobalt-manganese solution 3, the Ni concentration is 18.0445 g / L, the Co concentration is 3.0161 g / L, the Mn concentration is 8.3615 g / L, the Li concentration is 0.1062 g / L, the Al concentration is 0.0008 g / L, and the Fe concentration is 0.0006 g / L;

[0141] Through the above process, a Ni leaching rate of 97.15%, a Co leaching rate of 96.77%, a Mn leaching rate of 95.65%, and a Li leaching rate of 99.26% can be obtained.

[0142] Comparative Example 1:

[0143] This comparative example provides a method for recycling waste ternary battery powder, which specifically includes the following steps:

[0144] (1) Combined roasting. Mix waste ternary battery powder and iron-aluminum slag in a mass ratio of 25:1, introduce nitrogen and roast the mixture 1. Roast at 450℃ in the absence of oxygen for 2h to obtain roasted material 2.

[0145] (2) Lithium extraction by water leaching: The roasted material 2 was mixed with water for the first leaching, with a liquid-to-solid ratio of 5:1 mL / g, a temperature of 50°C, and a time of 2 h. After leaching and filtration, the leached residue 3 and the lithium-rich solution 1 were obtained.

[0146] (3) Acidification and reduction roasting. Ferrous sulfate and water-leached residue 3 were mixed evenly and roasted. The ratio of the amount of ferrous sulfate added to the amount of Ni+Co+Mn metal in the water-leached residue 3 was 0.3:1. The mixture was roasted at 480°C under nitrogen for 2 hours. The roasted material 4 was obtained.

[0147] (4) Water Leaching of Nickel, Cobalt and Manganese: The roasted material 4 was subjected to a second water leaching, with a liquid-to-solid ratio of 5:1 mL / g, a temperature of 60°C, and a time of 2 h. The nickel, cobalt and manganese leaching solution 2 and graphite slag 5 were separated by filtration.

[0148] (5) Impurity removal. The nickel-cobalt-manganese leaching solution 2 is maintained at 95°C, and sodium hydroxide is added to adjust the solution pH to 5.5 to remove iron and aluminum impurities. After filtration and separation, pure nickel-cobalt-manganese solution 3 and iron-aluminum slag 6 are obtained. The iron-aluminum slag 6 can be used as a mixing ingredient for waste ternary battery powder.

[0149] Passed ICP element test,

[0150] Mixture 1: Ni content 19.8221%, Co content 3.9153%, Mn content 10.0649%, Li content 4.2625%, Al content 0.3142%, Fe content 1.5455%;

[0151] Lithium-rich solution 1: Ni concentration 0.0014 g / L, Co concentration 0.0008 g / L, Mn concentration 0.0011 g / L, Li concentration 3.6532 g / L, Al concentration 0.0017 g / L, Fe concentration 0.0015 g / L;

[0152] Graphite slag 4: Ni content 13.8258%, Co content 2.8731%, Mn content 8.0764%, Li content 2.8472%, Al content 0.592%, Fe content 3.0553%;

[0153] In the pure nickel-cobalt-manganese solution 3, the Ni concentration is 10.6552 g / L, the Co concentration is 2.0219 g / L, the Mn concentration is 4.5390 g / L, the Li concentration is 0.0138 g / L, the Al concentration is 0.0001 g / L, and the Fe concentration is 0.0031 g / L;

[0154] Through the above process, a Ni leaching rate of 52.32%, a Co leaching rate of 50.48%, a Mn leaching rate of 44.69%, and a Li leaching rate of 51.28% can be obtained.

[0155] Comparative Example 2:

[0156] This comparative example provides a method for recycling waste ternary battery powder, which specifically includes the following steps:

[0157] (1) Combined roasting: Mix the waste ternary battery powder with 1.2 times the theoretical amount of ammonium sulfate, introduce nitrogen and roast the mixture 1. Roast at 450℃ in the absence of oxygen for 2h to obtain roasted material 2.

[0158] (2) Lithium extraction by water leaching: The roasted material 2 was mixed with water for the first leaching, with a liquid-to-solid ratio of 5:1 mL / g, a temperature of 50°C, and a time of 2 h. After leaching and filtration, the leached residue 3 and the lithium-rich solution 1 were obtained.

[0159] (3) Acidification and reduction roasting. Ferrous sulfate and water-leached residue 3 were mixed evenly and roasted. The ratio of the amount of ferrous sulfate added to the amount of Ni+Co+Mn metal in the water-leached residue 3 was 0.3:1. The mixture was roasted at 480°C under nitrogen for 2 hours. The roasted material 4 was obtained.

[0160] (4) Water Leaching of Nickel, Cobalt and Manganese: The roasted material 4 was subjected to a second water leaching, with a liquid-to-solid ratio of 5:1 mL / g, a temperature of 60°C, and a time of 2 h. The nickel, cobalt and manganese leaching solution 2 and graphite slag 5 were separated by filtration.

[0161] (5) Impurity removal. The nickel-cobalt-manganese leaching solution 2 is maintained at 95°C, and sodium hydroxide is added to adjust the solution pH to 5.5 to remove iron and aluminum impurities. After filtration and separation, pure nickel-cobalt-manganese solution 3 and iron-aluminum slag 6 are obtained. The iron-aluminum slag 6 can be used as a mixing ingredient for waste ternary battery powder.

[0162] Passed ICP element test,

[0163] Mixture 1: Ni content 20.2254%, Co content 3.8526%, Mn content 10.1748%, Li content 4.2891%, Al content 0.2986%, Fe content 0.5867%;

[0164] Lithium-rich solution 1: Ni concentration 0.0024 g / L, Co concentration 0.0019 g / L, Mn concentration 0.0036 g / L, Li concentration 7.0236 g / L, Al concentration 0.0062 g / L, Fe concentration 0.0001 g / L;

[0165] Graphite slag 4: Ni content 0.5457%, Co content 0.1229%, Mn content 0.7641%, Li content 0.022%, Al content 1.0028%, Fe content 1.2163%;

[0166] In the pure nickel-cobalt-manganese solution 3, the Ni concentration is 19.0382 g / L, the Co concentration is 3.1513 g / L, the Mn concentration is 7.2841 g / L, the Li concentration is 0.6253 g / L, the Al concentration is 0.0011 g / L, and the Fe concentration is 0.0009 g / L;

[0167] Through the above process, a Ni leaching rate of 91.42%, a Co leaching rate of 90.18%, a Mn leaching rate of 87.63%, and a Li leaching rate of 94.59% can be obtained.

[0168] Comparative Example 3

[0169] This comparative example provides a method for recycling waste ternary battery powder, which differs from Example 1 only in that in step (1), the waste ternary battery powder is mixed with 1.2 times the theoretical amount of natronasite and then calcined by introducing nitrogen.

[0170] Passed ICP element test,

[0171] Mixture 1: Ni content 19.5423%, Co content 3.9165%, Mn content 10.025%, Li content 4.2513%, Al content 0.6117%, Fe content 2.368%;

[0172] Lithium-rich solution 1: Ni concentration 0.0005 g / L, Co concentration 0.0009 g / L, Mn concentration 0.0013 g / L, Li concentration 7.9235 g / L, Al concentration 0.0010 g / L, Fe concentration 0.0009 g / L;

[0173] Graphite slag 4: Ni content 0.1526%, Co content 0.0621%, Mn content 0.1735%, Li content 0.0019%, Al content 1.2064%, Fe content 4.7325%;

[0174] In the pure nickel-cobalt-manganese solution 3, the Ni concentration is 19.7472 g / L, the Co concentration is 3.5421 g / L, the Mn concentration is 9.0515 g / L, the Li concentration is 0.1765 g / L, the Al concentration is 0.0012 g / L, and the Fe concentration is 0.0008 g / L;

[0175] Through the above process, Ni leaching rate of 98.95%, Co leaching rate of 98.58%, Mn leaching rate of 97.34%, and Li leaching rate of 97.63% can be obtained. Industrial Applicability

[0176] The ferroaluminum slag disclosed herein is derived from the primary product of the impurity removal process during wet-process battery recycling. The ferroaluminum slag is co-roasted with spent ternary battery powder. This allows the conversion of lithium using the sodium aluminum sulfate and sodium ferroaluminum sulfate contained in the ferroaluminum slag. Furthermore, trace amounts of nickel, cobalt, and manganese remaining in the ferroaluminum slag can be recycled along with the nickel, cobalt, and manganese in the spent ternary battery powder. This embodiment utilizes a combination of pyrometallurgical and hydrometallurgical processes, which is beneficial for improving lithium recovery, reducing the cost of auxiliary materials and reagents, simplifying the process, and improving production efficiency.

Claims

1. A method for recycling waste ternary battery powder, characterized in that: include: Roasting, anaerobic roasting of the first mixed material containing waste ternary battery powder and iron-aluminum slag to obtain a first roasted material; Water leaching of lithium, mixing the first roasted material with water for first leaching and solid-liquid separation, to obtain first water leaching residue and lithium-rich solution.

2. The method for recycling waste ternary battery powder according to claim 1, characterized in that: The mass ratio of waste ternary battery powder and iron-aluminum slag in the first mixture is (5-20):

1.

3. The method for recycling waste ternary battery powder according to claim 1 or 2, characterized in that: The calcination temperature of the oxygen-free calcination step is 300° C. to 550° C., and the calcination time is 1 hour to 3 hours.

4. The method for recycling waste ternary battery powder according to any one of claims 1 to 3, characterized in that: The main components of the ferroaluminum slag include 9.0wt%-9.5wt% of natto aluminum sulfate and 27wt%-28wt% of natto iron sulfate.

5. The method for recycling waste ternary battery powder according to any one of claims 1 to 4, characterized in that: The mass ratio of waste ternary battery powder and iron-aluminum slag in the first mixture is (8-10):

1.

6. The method for recycling waste ternary battery powder according to any one of claims 1 to 5, characterized in that: The first mixed material contains 18wt% to 20wt% Ni, 3.5wt% to 4.0wt% Co, 9.5wt% to 10.0wt% Mn, 4.0wt% to 4.5wt% Li, 0.6 to 0.8% Al and 2.5wt% to 2.7wt% Fe.

7. The method for recycling waste ternary battery powder according to any one of claims 1 to 6, characterized in that: The first roasted material is mixed with water at a liquid-to-solid ratio of 3 mL / g to 9 mL / g for the first leaching.

8. The method for recycling waste ternary battery powder according to any one of claims 1 to 7, characterized in that: The temperature of the water leaching lithium step is 30° C. to 90° C., and the time is 0.5 h to 3 h.

9. The method for recycling waste ternary battery powder according to any one of claims 1 to 8, characterized in that: The lithium-rich solution has a Ni concentration of less than 0.0015 g / L, a Co concentration of less than 0.0015 g / L, a Mn concentration of less than 0.01 g / L, a Li concentration of greater than 7.5 g / L, an Al concentration of less than 0.0025 g / L, and a Fe concentration of less than 0.004 g / L.

10. The method for recycling waste ternary battery powder according to any one of claims 1 to 9, characterized in that: Also includes: The first water-leached residue is mixed with ferrous sulfate and subjected to acid reduction roasting to obtain a second roasted material; The second roasted material is mixed with water for a second leaching and solid-liquid separation to obtain graphite slag and nickel-cobalt-manganese leaching solution.

11. The method for recycling waste ternary battery powder according to claim 10, characterized in that: The ratio of the total molar amount of nickel, cobalt and manganese in the first water-leached residue to the molar amount of ferrous sulfate is (0.5-2.5):

1.

12. The method for recycling waste ternary battery powder according to claim 10 or 11, characterized in that: The calcination temperature of the acid reduction calcination is 300° C. to 900° C., and the calcination time is 1 hour to 3 hours.

13. The method for recycling waste ternary battery powder according to any one of claims 10 to 12, characterized in that: The second calcined material is mixed with water at a liquid-to-solid ratio of 2 mL / g to 6 mL / g.

14. The method for recycling waste ternary battery powder according to any one of claims 10 to 13, characterized in that: The temperature of the second leaching is 30° C. to 90° C., and the time is 0.5 h to 3 h.

15. The method for recycling waste ternary battery powder according to any one of claims 10 to 14, characterized in that: The pH of the nickel-cobalt-manganese leaching solution is adjusted to 4.0-6.0 to precipitate iron and aluminum, and then solid-liquid separation is performed to obtain a nickel-cobalt-manganese leaching solution with impurities removed and iron-aluminum slag.

16. The method for recycling waste ternary battery powder according to claim 15, characterized in that: The temperature of the iron and aluminum precipitation step is 90°C to 95°C.

17. The method for recycling waste ternary battery powder according to claim 15 or 16, characterized in that: The nickel-cobalt-manganese leaching solution has a Ni concentration greater than 19.5 g / L, a Co concentration greater than 3.2 g / L, a Mn concentration greater than 9.1 g / L, a Li concentration less than 0.14 g / L, an Al concentration less than 0.002 g / L, and a Fe concentration less than 0.0025 g / L.

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