Method for leaching important metals in waste lithium batteries by using organic solvent under assistance of photocatalysis technology
Through photocatalytic technology assisted with organic solvent leaching method, the high energy consumption and secondary pollution problems of metal recycling in waste lithium batteries are solved, and the efficient and low-cost metal recycling effect is achieved, which is suitable for industrial production.
Patent Information
- Application Number
- CN202510665029.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-22
- Publication Date
- 2025-08-26
AI Technical Summary
The prior art has problems of high energy consumption, high cost and secondary pollution when recycling metals in waste lithium batteries. In particular, the use of acid leaching in wet recycling methods leads to high maintenance costs and corrosive wastewater.
Photocatalytic technology assisted with organic solvent leaching method, the metal in the cathode material of waste ternary lithium battery is leached in organic solvents through TiO2 photocatalyst, and non-toxic or low-toxic reagents are used to combine oxidation and reduction to achieve efficient metal recovery.
It realizes high-efficiency, low-cost, and no secondary pollution. It has high leaching efficiency and simple operation and is suitable for industrial production.
Smart Images
Figure CN120536725A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of waste lithium battery recycling, and relates to a novel recycling process for leaching nickel, cobalt, manganese, lithium and other metals from waste ternary lithium batteries. Background Art
[0002] While valuable metals such as nickel, cobalt, and lithium are abundant in the Earth's crust, most of these minerals are located in Africa and Australia, contributing to persistently high prices for these metals. The recent rise in electric vehicles and the promotion of ternary lithium-ion batteries has further fueled these prices. Therefore, recycling metals from used metal-containing materials is a key approach to addressing the challenges of limited metal resources and easing high metal prices.
[0003] The world produces over 50 million tons of e-waste annually, with each ton yielding an average of 300g of gold, 1000g of silver, 150g of copper, and 2000g of rare metals. Lithium batteries account for over 50% of this e-waste, making them the primary recyclable resource.
[0004] As the most promising rechargeable battery, lithium-ion batteries have high energy density, excellent cycle performance, and can be charged and discharged quickly. The positive and negative electrodes of lithium-ion batteries contain a large amount of metals such as Ni, Co, and Li, which are of great economic value. If they are discarded or landfilled at will, it will not only cause serious environmental pollution, but also cause a large amount of waste of metal resources. Therefore, recycling the important metals in lithium-ion batteries is not only of great practical significance for environmental protection and resource utilization, but also has huge economic benefits.
[0005] The main methods used to recycle used lithium batteries are pyrolysis and wet recycling. Pyrolysis has high energy consumption and its tail gas emissions can cause serious air pollution. Wet recovery has high efficiency and high recovery purity, but because acid leaching is often used, it is highly corrosive, the equipment maintenance cost is high, and the acid-containing wastewater will also cause secondary pollution.
[0006] The main method used in this application to recycle waste lithium batteries is organic solvent-assisted photocatalytic leaching. The wet method has high recovery efficiency and high recovery purity. It not only has lower costs and shortens reaction time, but also achieves high-efficiency and high-purity metal recovery, thus providing a new technical route for recycling waste lithium batteries. Summary of the Invention
[0007] The present invention aims to provide a technology for the photocatalytic leaching of important metals using an organic solvent-assisted method and its application in the field of recycling waste lithium batteries. The method has readily available raw materials, low production costs, and is industrializable and has a wide range of applications.
[0008] In order to achieve the above object, the present invention adopts the following technical solutions:
[0009] The present invention provides a novel recovery process for extracting important metals from waste ternary lithium battery cathode materials using photocatalytic technology-assisted organic solvent leaching. The steps are as follows:
[0010] (1) Pre-processing of waste lithium-ion batteries;
[0011] (2) Leaching the metal from the cathode powder using an organic solvent under photocatalytic conditions;
[0012] (3) centrifugation;
[0013] (4) Filter to obtain the leachate and filter residue.
[0014] The pretreatment process of the waste ternary lithium battery in step (1) includes: deep discharge treatment with 1 mol / L sodium chloride or potassium chloride solution, drying after deep discharge, and then manually disassembling to separate the shell, diaphragm, positive electrode and negative electrode, with the positive electrode reserved. The disassembled waste lithium battery positive electrode material is crushed by direct crushing and screening method to remove Al foil, and finally heated at 200-300℃. Heat treatment was carried out under the following conditions and the pyrolysis time was 1 h to obtain black positive electrode powder.
[0015] The reaction process in step (2) includes: adding TiO2 photocatalyst under light conditions, the amount of which is 50mg to 1g, Four different mixed reagent systems, namely acetonitrile-dichloromethane, acetonitrile-ethylene glycol, formamide-dichloromethane and ethylene glycol-dichloromethane, were added for leaching, with the solid-liquid ratio set at 1 g / L to 30 g / L, the volume ratio of the organic solvent at 4:1 to 1:1, and the leaching time at 10 h to 20 h.
[0016] The centrifugation process in step (3) includes: a centrifuge speed of 8000 rpm and a centrifugation time of 5 to 20 minutes.
[0017] The filtration process in step (4) includes: a filtration device including a Buchner funnel, a filtration bottle, a vacuum pump and filter paper, filtration for 2 to 3 minutes, the filtrate is collected in a sample bottle, and the filter residue is dried at 60° C. for 10 hours to obtain a dry powder.
[0018] The beneficial effects of the present invention are:
[0019] Reagent advantages: All reagents are non-toxic or low-toxic, green and environmentally friendly, and can be recycled and reused through distillation purification after the reaction, without producing concentrated acid wastewater. The TiO2 photocatalyst can be recycled and used multiple times after recovery and still maintains stable performance, without secondary pollution, and has high leaching efficiency.
[0020] Process Advantages: The photocatalytic process combines both oxidation and reduction, leaching as much of the metal from spent lithium batteries as possible. Furthermore, the active free radicals formed by the interaction of organic reagents with photogenerated holes and superoxide radicals formed by oxygen molecules also have oxidative effects, further enhancing leaching efficiency. The entire process requires no high temperatures, mild reaction conditions, and is simple to operate. It does not require specialized large-scale equipment, resulting in low cost and minimal energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 The reaction mechanism and technical roadmap for leaching metals from spent lithium batteries using photocatalysis-assisted organic solvents.
[0022] Figure 2 The SEM image and EDS spectrum of the powder sample prepared in Example 7 of the present invention are shown.
[0023] Figure 3 The infrared spectra of acetonitrile, dichloromethane, acetonitrile-dichloromethane mixed solvent and leachate prepared in Example 7 of the present invention.
[0024] Figure 4 These are the XRD patterns of the positive electrode powder before leaching reaction and the filter residue after leaching reaction in Example 7 of the present invention, and the XRD pattern of the product powder obtained after drying the leachate.
[0025] Figure 5 This is the XPS spectrum of the metals in the positive electrode powder before reaction, the leachate after reaction, and the filter residue after drying in Example 7 of the present invention.
[0026] Figure 6 The EPR spectra in the acetonitrile-dichloromethane mixed solvent system measured under different conditions in Example 7 of the present invention are shown. Specific implementation plan
[0027] The present invention is described below in conjunction with the embodiments, but it is necessary to explain here that these examples are only for further elaboration of the present invention and are not limitations of the claims of the present invention. Those skilled in the art can refer to the contents of this article and make some non-essential improvements and adjustments. It is particularly important to point out that all similar replacements and modifications are obvious to those skilled in the art and are considered to be included in the present invention. Based on the embodiments of the present invention, all other embodiments obtained by the relevant personnel without making creative work are within the scope of protection of the present invention. In the following examples, the ratios involved are all by mass.
[0028] Example 1
[0029] The method of leaching important metals from waste ternary lithium batteries in this embodiment is as follows: Figure 1 As shown, the specific process is as follows:
[0030] Pre-process the spent ternary lithium batteries: Place the spent ternary lithium batteries in a beaker and immerse them in a 1 mol / L sodium chloride or potassium chloride solution for a deep discharge of 5 hours. After full discharge, place the batteries in an oven and dry them at 60°C for 24 hours. Then, manually disassemble them with pliers, separating the positive electrode material, negative electrode material, separator, and casing. The positive electrode material is then set aside for later use. A powder sample of the positive electrode material is obtained using a crushing and sorting device, and finally heat-treated at 200°C.
[0031] Leaching of waste ternary lithium batteries: weigh 1g of waste ternary lithium battery powder, add 50mg of TiO2 photocatalyst, then add 100mL of ethylene glycol and dichloromethane with a volume ratio of 3:1, mix after ultrasonication, apply light, and react for 10h.
[0032] The reaction solution was centrifuged and filtered at 4000 rpm for 5 min.
[0033] The centrifuged leaching solution was filtered: the solution was quickly poured out and filtered for 2 to 3 minutes to obtain the Li-containing + 、Co 2+ 、Mn 2 + 、Ni 2+ 、Fe 3+ 、Cu 2+ 、Al 3+ of the leachate.
[0034] Finally, in the leachate, Li + 、Mn 2+ 、Co 2+ 、Ni 2+ 、Fe 3+ 、Cu 2+ 、Al 3+ The leaching efficiencies were 6.29%, 13.04%, 24.27%, 3.11%, 8.14%, 0% and 0% respectively.
[0035] Example 2
[0036] The method of leaching important metals from waste ternary lithium batteries in this embodiment is as follows: Figure 1 As shown, the specific process is as follows:
[0037] Pre-process the spent ternary lithium batteries: Place the spent ternary lithium batteries in a beaker and immerse them in a 1 mol / L sodium chloride or potassium chloride solution for a deep discharge of 5 hours. After full discharge, place the batteries in an oven and dry them at 60°C for 24 hours. Then, manually disassemble them with pliers, separating the positive electrode material, negative electrode material, separator, and casing. The positive electrode material is then set aside for later use. A powder sample of the positive electrode material is obtained using a crushing and sorting device, and finally heat-treated at 200°C.
[0038] Leaching of waste ternary lithium batteries: weigh 1g of waste ternary lithium battery powder, add 100mg of TiO2 photocatalyst, then add 100mL of ethylene glycol and dichloromethane with a volume ratio of 3:1, mix after ultrasonication, apply light, and react for 10h.
[0039] The reaction solution was centrifuged and filtered at 4000 rpm for 5 min.
[0040] The centrifuged leaching solution was filtered: the solution was quickly poured out and filtered for 2 to 3 minutes to obtain the Li-containing + 、Co 2+ 、Mn 2 + 、Ni 2+ 、Fe 3+ 、Cu 2+ 、Al 3+ of the leachate.
[0041] Finally, in the leachate, Li + 、Co 2+ 、Mn 2+ 、Ni 2+ 、Fe 3+ 、Cu 2+ 、Al 3+ The leaching efficiencies were 10.19%, 14.23%, 27.11%, 3.71%, 9.45%, 0% and 0% respectively.
[0042] Example 3
[0043] The method of leaching important metals from waste ternary lithium batteries in this embodiment is as follows: Figure 1 As shown, the specific process is as follows:
[0044] Pre-process the spent ternary lithium batteries: Place the spent ternary lithium batteries in a beaker and immerse them in a 1 mol / L sodium chloride or potassium chloride solution for a deep discharge of 5 hours. After full discharge, place the batteries in an oven and dry them at 60°C for 24 hours. Then, manually disassemble them with pliers, separating the positive electrode material, negative electrode material, separator, and casing. The positive electrode material is then set aside for later use. A powder sample of the positive electrode material is obtained using a crushing and sorting device, and finally heat-treated at 200°C.
[0045] Leaching of waste ternary lithium batteries: weigh 1g of waste ternary lithium battery powder, add 50mg of TiO2 photocatalyst, then add 100mL of acetonitrile and dichloromethane with a volume ratio of 3:1, mix after ultrasonication, apply light, and react for 10h.
[0046] The reaction solution was centrifuged and filtered at 4000 rpm for 5 min.
[0047] The centrifuged leaching solution was filtered: the solution was quickly poured out and filtered for 2 to 3 minutes to obtain the Li-containing + 、Co 2+ 、Mn 2 + 、Ni 2+ 、Fe 3+ 、Cu 2+ 、Al 3+ of the leachate.
[0048] Finally, in the leachate, Li + 、Co 2+ 、Mn 2+ 、Ni 2+ 、Fe 3+ 、Cu 2+ 、Al 3+ The leaching efficiencies were 13.18%, 25.84%, 29.07%, 0.064%, 5.97%, 51.77% and 0.69% respectively.
[0049] Example 4
[0050] The method of leaching important metals from waste ternary lithium batteries in this embodiment is as follows: Figure 1 As shown, the specific process is as follows:
[0051] Pre-process the spent ternary lithium batteries: Place the spent ternary lithium batteries in a beaker and immerse them in a 1 mol / L sodium chloride or potassium chloride solution for a deep discharge of 5 hours. After full discharge, place the batteries in an oven and dry them at 60°C for 24 hours. Then, manually disassemble them with pliers, separating the positive electrode material, negative electrode material, separator, and casing. The positive electrode material is then set aside for later use. A powder sample of the positive electrode material is obtained using a crushing and sorting device, and finally heat-treated at 200°C.
[0052] Leaching of waste ternary lithium batteries: weigh 1g of waste ternary lithium battery powder, add 100mg of TiO2 photocatalyst, then add 100mL of acetonitrile and dichloromethane with a volume ratio of 3:1, mix after ultrasonication, apply light, and react for 10h.
[0053] The reaction solution was centrifuged and filtered at 4000 rpm for 5 min.
[0054] The centrifuged leaching solution was filtered: the solution was quickly poured out and filtered for 2 to 3 minutes to obtain the Li-containing + 、Co 2+ 、Mn 2 + 、Ni 2+ 、Fe 3+ 、Cu 2+ 、Al 3+ of the leachate.
[0055] Finally, in the leachate, Li + 、Co 2+ 、Mn 2+ 、Ni 2+ 、Fe 3+ 、Cu 2+ 、Al 3+ The leaching efficiencies were 17.63%, 33.20%, 36.64%, 1.33%, 9.11%, 73.21% and 0.21% respectively.
[0056] Example 5
[0057] The method of leaching important metals from waste ternary lithium batteries in this embodiment is as follows: Figure 1 As shown, the specific process is as follows:
[0058] Pre-process the spent ternary lithium batteries: Place the spent ternary lithium batteries in a beaker and immerse them in a 1 mol / L sodium chloride or potassium chloride solution for a deep discharge of 5 hours. After full discharge, place the batteries in an oven and dry them at 60°C for 24 hours. Then, manually disassemble them with pliers, separating the positive electrode material, negative electrode material, separator, and casing. The positive electrode material is then set aside for later use. A powder sample of the positive electrode material is obtained using a crushing and sorting device, and finally heat-treated at 200°C.
[0059] Leaching of waste ternary lithium batteries: weigh 1g of waste ternary lithium battery powder, add 200mg of TiO2 photocatalyst, then add 100mL of acetonitrile and dichloromethane with a volume ratio of 3:1, mix after ultrasonication, apply light, and react for 10h.
[0060] The reaction solution was centrifuged and filtered at 4000 rpm for 5 min.
[0061] The centrifuged leaching solution was filtered: the solution was quickly poured out and filtered for 2 to 3 minutes to obtain the Li-containing + 、Co 2+ 、Mn 2 + 、Ni 2+ 、Fe 3+ 、Cu 2+ 、Al 3+ of the leachate.
[0062] Finally, in the leachate, Li + 、Co 2+ 、Mn 2+ 、Ni 2+ 、Fe 3+ 、Cu 2+ 、Al 3+ The leaching efficiencies were 20.11%, 34.95%, 37.64%, 4.46%, 12.11%, 77.43% and 0.67% respectively.
[0063] Example 6
[0064] The method of leaching important metals from waste ternary lithium batteries in this embodiment is as follows: Figure 1 As shown, the specific process is as follows:
[0065] Pre-process the spent ternary lithium batteries: Place the spent ternary lithium batteries in a beaker and immerse them in a 1 mol / L sodium chloride or potassium chloride solution for a deep discharge of 5 hours. After full discharge, place the batteries in an oven and dry them at 60°C for 24 hours. Then, manually disassemble them with pliers, separating the positive electrode material, negative electrode material, separator, and casing. The positive electrode material is then set aside for later use. A powder sample of the positive electrode material is obtained using a crushing and sorting device, and finally heat-treated at 200°C.
[0066] Leaching of waste ternary lithium batteries: weigh 1g of waste ternary lithium battery powder, add 500mg of TiO2 photocatalyst, then add 100mL of acetonitrile and dichloromethane with a volume ratio of 3:1, mix after ultrasonication, apply light, and react for 10h.
[0067] The reaction solution was centrifuged and filtered at 4000 rpm for 5 min.
[0068] The centrifuged leaching solution was filtered: the solution was quickly poured out and filtered for 2 to 3 minutes to obtain the Li-containing + 、Co 2+ 、Mn 2 + 、Ni 2+ 、Fe 3+ 、Cu 2+ 、Al 3+ + leachate.
[0069] Finally, in the leachate, Li + 、Co 2+ 、Mn 2+ 、Ni 2+ 、Fe 3+ 、Cu 2+ 、Al 3+ The leaching efficiencies were 17.94%, 37.94%, 38.49%, 3%, 11.33%, 38.93% and 0.22% respectively.
[0070] Example 7
[0071] The method of leaching important metals from waste ternary lithium batteries in this embodiment is as follows: Figure 1 As shown, the specific process is as follows:
[0072] Pre-process the spent ternary lithium batteries: Place the spent ternary lithium batteries in a beaker and immerse them in a 1 mol / L sodium chloride or potassium chloride solution for a deep discharge of 5 hours. After full discharge, place the batteries in an oven and dry them at 60°C for 24 hours. Then, manually disassemble them with pliers, separating the positive electrode material, negative electrode material, separator, and casing. The positive electrode material is then set aside for later use. A powder sample of the positive electrode material is obtained using a crushing and sorting device, and finally heat-treated at 200°C.
[0073] Leaching of waste ternary lithium batteries: weigh 1g of waste ternary lithium battery powder, add 100mg of TiO2 photocatalyst, then add 100mL of acetonitrile and dichloromethane with a volume ratio of 3:1, mix after ultrasonication, apply light, and react for 15h.
[0074] The reaction solution was centrifuged and filtered at 4000 rpm for 5 min.
[0075] The centrifuged leaching solution was filtered: the solution was quickly poured out and filtered for 2 to 3 minutes to obtain the Li-containing + 、Co 2+ 、Mn 2 + 、Ni 2+ 、Fe 3+ 、Cu 2+ 、Al 3+ of the leachate.
[0076] Finally, in the leachate, Li + 、Co 2+ 、Mn 2+ 、Ni 2+ 、Fe 3+ 、Cu 2+ 、Al 3+ The leaching efficiencies were 72.43%, 92.52%, 97.63%, 4.5%, 15.16%, 98.72% and 0.67% respectively.
[0077] Example 8
[0078] The method of leaching important metals from waste ternary lithium batteries in this embodiment is as follows: Figure 1 As shown, the specific process is as follows:
[0079] Pre-process the spent ternary lithium batteries: Place the spent ternary lithium batteries in a beaker and immerse them in a 1 mol / L sodium chloride or potassium chloride solution for a deep discharge of 5 hours. After full discharge, place the batteries in an oven and dry them at 60°C for 24 hours. Then, manually disassemble them with pliers, separating the positive electrode material, negative electrode material, separator, and casing. The positive electrode material is then set aside for later use. A powder sample of the positive electrode material is obtained using a crushing and sorting device, and finally heat-treated at 200°C.
[0080] Leaching of waste ternary lithium batteries: weigh 1g of waste ternary lithium battery powder, add 100mg of TiO2 photocatalyst, then add 100mL of acetonitrile and dichloromethane with a volume ratio of 3:1, mix after ultrasonication, apply light, and react for 20h.
[0081] The reaction solution was centrifuged and filtered at 4000 rpm for 5 min.
[0082] The centrifuged leaching solution was filtered: the solution was quickly poured out and filtered for 2 to 3 minutes to obtain the Li-containing + 、Co 2+ 、Mn 2 + 、Ni 2+ 、Fe 3+ 、Cu 2+ 、Al 3+ of the leachate.
[0083] Finally, in the leachate, Li + 、Co 2+ 、Mn 2+ 、Ni 2+ 、Fe 3+ 、Cu 2+ 、Al 3+ The leaching efficiencies were 18.96%, 34.5%, 41.92%, 2.17%, 17.23%, 63.55% and 0.36% respectively.
[0084] Example 9
[0085] The method of leaching important metals from waste ternary lithium batteries in this embodiment is as follows: Figure 1 As shown, the specific process is as follows:
[0086] Pre-process the spent ternary lithium batteries: Place the spent ternary lithium batteries in a beaker and immerse them in a 1 mol / L sodium chloride or potassium chloride solution for a deep discharge of 5 hours. After full discharge, place the batteries in an oven and dry them at 60°C for 24 hours. Then, manually disassemble them with pliers, separating the positive electrode material, negative electrode material, separator, and casing. The positive electrode material is then set aside for later use. A powder sample of the positive electrode material is obtained using a crushing and sorting device, and finally heat-treated at 200°C.
[0087] Leaching of waste ternary lithium batteries: weigh 1g of waste ternary lithium battery powder, add 50mg of TiO2 photocatalyst, then add 100mL of ethylene glycol and acetonitrile with a volume ratio of 3:1, mix after ultrasonication, apply light, and react for 10h.
[0088] The reaction solution was centrifuged and filtered at 4000 rpm for 5 min.
[0089] The centrifuged leaching solution was filtered: the solution was quickly poured out and filtered for 2 to 3 minutes to obtain the Li-containing + 、Co 2+ 、Mn 2 + 、Ni 2+ 、Fe 3+ 、Cu 2+ 、Al 3+ of the leachate.
[0090] Finally, in the leachate, Li + 、Co 2+ 、Mn 2+ 、Ni 2+ 、Fe 3+ 、Cu 2+ 、Al 3+ The leaching efficiencies were 16.7%, 0.48%, 0%, 0.085%, 0%, 0%, and 0%, respectively.
[0091] Example 10
[0092] The method of leaching important metals from waste ternary lithium batteries in this embodiment is as follows: Figure 1 As shown, the specific process is as follows:
[0093] Pre-process the spent ternary lithium batteries: Place the spent ternary lithium batteries in a beaker and immerse them in a 1 mol / L sodium chloride or potassium chloride solution for a deep discharge of 5 hours. After full discharge, place the batteries in an oven and dry them at 60°C for 24 hours. Then, manually disassemble them with pliers, separating the positive electrode material, negative electrode material, separator, and casing. The positive electrode material is then set aside for later use. A powder sample of the positive electrode material is obtained using a crushing and sorting device, and finally heat-treated at 200°C.
[0094] Leaching of waste ternary lithium batteries: weigh 1g of waste ternary lithium battery powder, add 50mg of TiO2 photocatalyst, then add 100mL of ethylene glycol and acetonitrile with a volume ratio of 1:3, mix after ultrasonication, apply light, and react for 10h.
[0095] The reaction solution was centrifuged and filtered at 4000 rpm for 5 min.
[0096] The centrifuged leaching solution was filtered: the solution was quickly poured out and filtered for 2 to 3 minutes to obtain the Li-containing + 、Co 2+ 、Mn 2 + 、Ni 2+ 、Fe 3+ 、Cu 2+ 、Al 3+ of the leachate.
[0097] Finally, in the leachate, Li + 、Co 2+ 、Mn 2+ 、Ni 2+ 、Fe 3+ 、Cu 2+ 、Al 3+ The leaching efficiencies were 18.4%, 0.18%, 0%, 0%, 0%, 0%, and 0%, respectively.
[0098] Example 11
[0099] The method of leaching important metals from waste ternary lithium batteries in this embodiment is as follows: Figure 1 As shown, the specific process is as follows:
[0100] Pre-process the spent ternary lithium batteries: Place the spent ternary lithium batteries in a beaker and immerse them in a 1 mol / L sodium chloride or potassium chloride solution for a deep discharge of 5 hours. After full discharge, place the batteries in an oven and dry them at 60°C for 24 hours. Then, manually disassemble them with pliers, separating the positive electrode material, negative electrode material, separator, and casing. The positive electrode material is then set aside for later use. A powder sample of the positive electrode material is obtained using a crushing and sorting device, and finally heat-treated at 200°C.
[0101] Leaching of waste ternary lithium batteries: weigh 1g of waste ternary lithium battery powder, add 50mg of TiO2 photocatalyst, then add 100mL of formamide and dichloromethane with a volume ratio of 3:1, mix after ultrasonication, apply light, and react for 10h.
[0102] The reaction solution was centrifuged and filtered at 4000 rpm for 5 min.
[0103] The centrifuged leaching solution was filtered: the solution was quickly poured out and filtered for 2 to 3 minutes to obtain the Li-containing + 、Co 2+ 、Mn 2 + 、Ni 2+ 、Fe 3+ 、Cu 2+ 、Al 3+ of the leachate.
[0104] Finally, in the leachate, Li + 、Co 2+ 、Mn 2+ 、Ni 2+ 、Fe 3+ 、Cu 2+ 、Al 3+ The leaching efficiencies were 46.11%, 68.31%, 67.25%, 34.22%, 39.32%, 84.44% and 5.18% respectively.
[0105] Example 12
[0106] The method of leaching important metals from waste ternary lithium batteries in this embodiment is as follows: Figure 1 As shown, the specific process is as follows:
[0107] Pre-process the spent ternary lithium batteries: Place the spent ternary lithium batteries in a beaker and immerse them in a 1 mol / L sodium chloride or potassium chloride solution for a deep discharge of 5 hours. After full discharge, place the batteries in an oven and dry them at 60°C for 24 hours. Then, manually disassemble them with pliers, separating the positive electrode material, negative electrode material, separator, and casing. The positive electrode material is then set aside for later use. A powder sample of the positive electrode material is obtained using a crushing and sorting device, and finally heat-treated at 200°C.
[0108] Leaching of waste ternary lithium batteries: weigh 1g of waste ternary lithium battery powder, add 100mg of TiO2 photocatalyst, then add 100mL of formamide and dichloromethane with a volume ratio of 3:1, mix after ultrasonication, apply light, and react for 10h.
[0109] The reaction solution was centrifuged and filtered at 4000 rpm for 5 min.
[0110] The centrifuged leaching solution was filtered: the solution was quickly poured out and filtered for 2 to 3 minutes to obtain the Li-containing + 、Co 2+ 、Mn 2 + 、Ni 2+ 、Fe 3+ 、Cu 2+ 、Al 3+ of the leachate.
[0111] Finally, in the leachate, Li + 、Co 2+ 、Mn 2+ 、Ni 2+ 、Fe 3+ 、Cu 2+ 、Al 3+ The leaching efficiencies were 45.11%, 71.31%, 74.25%, 39.08%, 43.32%, 89.01% and 6.73% respectively.
[0112] It will be easily understood by those skilled in the art that the above description is merely an illustrative example of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.
Claims
1. A novel recycling process for leaching important metals from spent ternary lithium battery cathode materials using photocatalytic technology, characterized in that: The following steps are involved: Pre-treat waste lithium-ion batteries; leach metals from cathode powder using organic solvents under photocatalytic conditions; centrifugal; Filter to obtain the leachate and filter residue.
2. The method for leaching important metals from waste ternary lithium batteries according to claim 1, characterized in that: The step (1) mainly includes deep discharge, manual disassembly, crushing and sorting, and heat treatment; the discharge process is carried out in a beaker; the crushing device is a ball mill; the sorting device is used to re-select the solid product to separate and recover the aluminum foil and copper foil from the solid product, and obtain a solid residue after the aluminum foil and the copper foil are separated; the heat treatment is carried out in a tubular furnace, and nitrogen is passed through the tubular furnace to produce solid products and volatile gases; the photocatalytic device includes a light-emitting device, a reaction device and an agitator; the pickling device is mainly used to wash out Mn in the solid; the filtration device includes a Buchner funnel, a filtration bottle, a gas conduit and a vacuum pump to separate the solid and liquid phases to obtain a Li-rich solution.
3. The method for leaching important metals from waste ternary lithium batteries according to claim 1, characterized in that: Step (1) specifically comprises the following steps: deep discharge treatment with a 1 mol / L NaCl or KCl solution, air drying after deep discharge, and then manual disassembly to separate the outer shell, diaphragm, positive electrode and negative electrode, with the positive electrode reserved. The disassembled waste lithium battery positive electrode material is crushed and the Al foil is removed by direct crushing and screening, and finally heat treated at 200-300°C for 1 hour to obtain a black positive electrode powder. The powder comprises any one or a combination of the following: carbon, cobalt oxide, manganese oxide, nickel oxide, lithium manganate, lithium nickel oxide, lithium cobalt oxide, and nickel cobalt lithium manganate.
4. The method for leaching important metals from waste ternary lithium batteries according to claim 1, characterized in that: In step (2), the photocatalyst is TiO2 with a content of 50 mg to 1 g, the organic solvents are acetonitrile-dichloromethane, acetonitrile-ethylene glycol, formamide-dichloromethane and ethylene glycol-dichloromethane, the solid-liquid ratio is 1 g / L to 30 g / L, and the volume ratio of the organic solvents is 4:1 to 1:
1.
5. The method for leaching important metals from waste ternary lithium batteries according to claim 1, characterized in that: In step (3), the centrifuge speed is 8000 rpm and the centrifugation time is 5 to 20 minutes.
6. The method for leaching important metals from waste ternary lithium batteries according to claim 1, characterized in that: In step (4), the filtration device includes a Buchner funnel, a filtration bottle, a vacuum pump and filter paper, and the filtrate is contained in a sample bottle.