Resource utilization method of waste ternary lithium battery positive electrode material

Abstract

The invention belongs to the technical field of waste battery resource utilization, and particularly relates to a waste ternary lithium battery positive electrode material resource utilization method, which comprises: crushing and screening a waste ternary lithium battery positive electrode material, adding pyrite, and carrying out heating calcination reaction in an air environment to obtain a solid A; pulping the solid A and water for reaction, and filtering after reaction to obtain a solid B and a solution B; adding a copper sulfate solution into the solid B and performing ultrasonic treatment to obtain a solution C; adding sodium hydroxide into the solution C to adjust the pH of the reaction system, and continuously performing ultrasonic treatment to obtain a solution D; performing hydrothermal reaction on the solution D, and centrifuging to obtain a solid C; adding the solid C into a solution containing antibiotics, and degrading the antibiotics through dark adsorption and illumination reaction; and after the filtrate B is enriched and purified, nickel, cobalt, manganese and lithium elements can be precipitated, separated and extracted, so that resource utilization of the waste ternary lithium battery positive electrode material is realized.

Description

Technical Field

[0001] The invention relates to the technical field of resource utilization of waste batteries, and in particular to a method for resource utilization of positive electrode materials of waste ternary lithium batteries. Background Art

[0002] With the rapid development of new energy vehicles and other industries, the use of ternary lithium batteries has increased dramatically, and a large number of waste ternary lithium batteries have been generated. On the one hand, the positive electrode materials of ternary lithium batteries contain valuable metals such as lithium, nickel, cobalt, and manganese. The reserves of these metal resources in nature are limited. If waste batteries are not effectively treated, these precious resources will be wasted. On the other hand, if waste ternary lithium batteries are not properly handled, the heavy metals and chemicals they contain may cause serious pollution to the environment, such as soil pollution and water pollution. Traditional methods for treating waste batteries often have problems such as low recovery rate, complex process, high cost or secondary pollution. For example, although some pyrometallurgical processes can extract some metals, they have high energy consumption and may produce harmful gases. In hydrometallurgy, some methods have strict requirements on equipment, and the leaching agent may have environmental risks. At present, there is an urgent need for an efficient, environmentally friendly and economical method for resource utilization of waste ternary lithium battery positive electrode materials to solve the problems of resource waste and environmental pollution, meet the requirements of sustainable development, increase the recycling rate of valuable metals in waste batteries, and at the same time reduce the impact of the treatment process on the environment, so as to realize the transformation of waste ternary lithium battery positive electrode materials from waste to resources. Summary of the invention

[0003] In order to solve the problems existing in the prior art, the main purpose of the present invention is to propose a method for resource utilization of waste ternary lithium battery positive electrode materials.

[0004] To solve the above technical problems, according to one aspect of the present invention, the present invention provides the following technical solutions: A method for recycling waste ternary lithium battery positive electrode materials, comprising the following steps: S1. After the waste ternary lithium battery positive electrode material is crushed and sieved, pyrite is added, and solid A is obtained after heating and calcination reaction in an air environment; S2, solid A is slurried with water for reaction, and after the reaction, solid B and filtrate B are obtained by filtration; S3, solid B is added with copper sulfate solution and then ultrasonicated to obtain solution C; S4, adding sodium hydroxide to solution C to adjust the pH of the reaction system and then continuing ultrasonication to obtain solution D; S5, solution D is subjected to hydrothermal reaction and then centrifuged to obtain solid C; S6. Solid C is added to a solution containing antibiotics, and the antibiotics are degraded through dark adsorption and light reaction. The filtrate B is enriched and impurities are removed, and then precipitated, separated and recovered.

[0005] As a preferred embodiment of the method for resource utilization of waste ternary lithium battery positive electrode materials described in the present invention, wherein: in the step S1, the particle size of the waste ternary lithium battery positive electrode material powder after crushing and sieving is ≤50 mesh; the molar ratio of lithium element in the waste ternary lithium battery positive electrode material after crushing and sieving to iron element in pyrite is 1:(1.10-1.80).

[0006] As a preferred embodiment of the method for resource utilization of waste ternary lithium battery positive electrode materials described in the present invention, wherein: in the step S1, a heating and calcining reaction is carried out in a tubular furnace, the heating and calcining reaction temperature is 400-700°C, the reaction time is 2.0-5.0h, and the air flow rate is 1-2L / min.

[0007] As a preferred embodiment of the method for resource utilization of waste ternary lithium battery positive electrode materials described in the present invention, wherein: in the step S2, the solid B is mainly iron oxide and carbon, the filtrate B is a solution containing nickel, cobalt, manganese and lithium, and the leaching rates of nickel, cobalt, manganese and lithium elements are all ≥97%. After enrichment and impurity removal, the nickel, cobalt, manganese and lithium elements can be precipitated and separated to extract.

[0008] As a preferred embodiment of the method for resource utilization of waste ternary lithium battery positive electrode materials described in the present invention, wherein: in the step S3, the solid-liquid ratio of solid B to copper sulfate solution is (0.5-2) g / 50 mL; the concentration of copper sulfate solution is 0.01-0.1 mol / L, and the ultrasonic time is 0.5 h.

[0009] As a preferred embodiment of the method for resource utilization of waste ternary lithium battery positive electrode materials described in the present invention, wherein: in the step S4, sodium hydroxide is added in the form of a solution, the concentration of the sodium hydroxide solution is 0.05-1 mol / L, and the ultrasonic time is 1 hour; the pH value of the reaction system is adjusted to 7-8.

[0010] As a preferred embodiment of the method for resource utilization of waste ternary lithium battery positive electrode materials described in the present invention, wherein: in the step S5, the hydrothermal reaction temperature is 100-150°C, and the reaction time is 3.0-6.0h.

[0011] As a preferred embodiment of the method for resource utilization of waste ternary lithium battery positive electrode materials described in the present invention, wherein: in the step S5, the solid C is an iron-copper complex, which is used as a catalyst for degrading antibiotics in water to achieve resource utilization.

[0012] As a preferred embodiment of the method for resource utilization of waste ternary lithium battery positive electrode materials described in the present invention, wherein: in the step S6, the antibiotics are a series of electron-rich antibiotics.

[0013] As a preferred embodiment of the method for resource utilization of waste ternary lithium battery positive electrode materials described in the present invention, wherein: in the step S6, the degradation rate of the antibiotic is 30-80%.

[0014] The beneficial effects of the present invention are as follows: The invention provides a method for resource utilization of waste ternary lithium battery positive electrode materials. After the waste ternary lithium battery positive electrode materials are crushed and screened, the crushed and screened pyrite is added, and solid A is obtained after heating and calcining reaction in an air environment; solid A is slurried with water for reaction, and solid B and solution B are obtained after filtering after reaction; solid B is added with copper sulfate solution and ultrasonically obtained solution C is obtained; sodium hydroxide is added to the solution C to adjust the pH value of the reaction system, and then ultrasonically obtained solution D is obtained; solution D is subjected to hydrothermal reaction and centrifuged to obtain solid C; solid C is added with a solution containing antibiotics, and the antibiotics are degraded through dark adsorption and light reaction; filtrate B can be precipitated and separated to extract nickel, cobalt, manganese and lithium elements after enrichment and impurity removal, so as to realize resource utilization of waste ternary lithium battery positive electrode materials. DETAILED DESCRIPTION

[0015] The following will be described clearly and completely in conjunction with the technical solutions in the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0016] According to one aspect of the present invention, the present invention provides the following technical solution: A method for recycling waste ternary lithium battery positive electrode materials, comprising the following steps: S1, the waste ternary lithium battery positive electrode material is crushed and sieved, and then the crushed and sieved pyrite is added, and the solid A is obtained after heating and calcining in an air environment; when heated and calcined in air, the main substance FeS2 in the pyrite, the waste ternary lithium battery positive electrode material and the oxygen in the air react to generate iron oxide and sulfur dioxide, and Fe (II) and S in FeS2 - Not only can it be used as a reducing agent, sulfur can also combine with nickel, cobalt, manganese and lithium, which is beneficial to the leaching of nickel, cobalt, manganese and lithium in the second step. In addition, the Fe element in FeS2 can also be used as a raw material for iron-based catalysts to achieve full utilization of resources; Ni (III), Co (III), Mn (III), Mn (IV) in the positive electrode materials of waste ternary lithium batteries and oxygen in the air act as oxidants, and sulfur combines with oxygen to generate sulfur trioxide. The chemical reaction equation that may occur during this period is as follows: 6LiMO2+ 2FeS2+6O2= 3Li2O + Fe2O3+ 6MO + 4SO3(M=Ni, Co, Mn) (1) 4FeS2+ 11O2= 2Fe2O3+ 8SO2(2) 2SO2+O2= 2SO3 (3) S2, solid A is slurried with water for reaction, and after the reaction, solid B and filtrate B are obtained by filtration; S3, solid B is added with copper sulfate solution and then ultrasonicated to obtain solution C; S4, adding sodium hydroxide to solution C to adjust the pH of the reaction system to 7-8 and then continue ultrasonication to obtain solution D; S5, solution D is subjected to hydrothermal reaction and then centrifuged to obtain solid C; S6. Solid C is added to a solution containing antibiotics, and the antibiotics are degraded through dark adsorption and light reaction.

[0017] Preferably, in the step S1, the particle size of the waste ternary lithium battery positive electrode material powder and the pyrite powder after crushing and sieving is ≤50 mesh; the particle size of the waste ternary lithium battery positive electrode material powder after crushing and sieving is ≤50 mesh; the molar ratio of lithium element in the waste ternary lithium battery positive electrode material to iron element in pyrite after crushing and sieving is 1:(1.10-1.80); heating and calcining reaction are carried out in a tubular furnace, the heating and calcining reaction temperature is 400-700°C, the reaction time is 2.0-5.0h, and the air flow rate is 1-2L / min.

[0018] Preferably, in step S2, the solid B is mainly iron oxide and carbon, and the filtrate B contains four elements of nickel, cobalt, manganese and lithium, and the leaching rate can reach more than 97%. After enrichment and impurity removal, it can be precipitated, separated and recovered, and can be used for resource utilization as raw materials for lithium-ion batteries, catalysts, ceramics and glass.

[0019] Preferably, in step S3, the solid-to-liquid ratio of solid B to copper sulfate solution is (0.5-2) g / 50 mL; the concentration of copper sulfate solution is 0.01-0.1 mol / L, and the ultrasonic time is 0.5 h.

[0020] Preferably, in step S4, sodium hydroxide is added in the form of a solution, the concentration of the sodium hydroxide solution is 0.05-1 mol / L, and the ultrasonic time is 1 h.

[0021] Preferably, in step S5, the hydrothermal reaction temperature is 100-150° C., and the reaction time is 3.0-6.0 h; the obtained solid C is an iron-copper complex, which is used as a catalyst for degrading antibiotics in water to achieve resource utilization.

[0022] Preferably, in step S6, the amount of solid C added to the antibiotic solution can be adjusted according to the antibiotic concentration. The greater the antibiotic concentration, the greater the amount of solid C added, and the degradation rate of the antibiotic can reach 30-80%.

[0023] The technical solution of the present invention is further described below in conjunction with specific embodiments.

[0024] Example 1 A method for recycling waste ternary lithium battery positive electrode materials, comprising the following steps: S1. 1 g of waste ternary positive electrode material powder with a particle size of ≤50 mesh and 2.2 g of pyrite powder with a particle size of ≤50 mesh (the molar ratio of lithium element in waste ternary lithium battery positive electrode material to iron element in pyrite is 1:1.15) are mixed evenly, put into a porcelain boat and placed in the middle of a tube furnace, air is introduced at a flow rate of 1 L / min, and heated and calcined at 600° C. for 2 h to obtain 2.87 g of calcined powder; S2, the calcined powder was slurried with 50 mL of water for reaction, and after filtration, a solution containing lithium, nickel, cobalt, manganese and a mixture containing iron were obtained. The contents of lithium, nickel, cobalt and manganese in the solution were detected by ICP. The leaching rates of lithium, nickel, cobalt and manganese were calculated to be 99.64%, 97.88%, 98.10% and 98.19%, respectively; S3, weighing 2 g of the iron-containing mixture of step S2, adding 50 mL of 0.01 mol / L copper sulfate solution and ultrasonicating for 0.5 h, then adding sodium hydroxide to adjust the pH of the reaction system to 7.8 and continue ultrasonicating for 1 h, and then putting the ultrasonicated liquid into a reactor for hydrothermal reaction, the reaction time is 3 h, the reaction temperature is 100 ° C, and centrifugation after the reaction to obtain an iron-copper complex.

[0025] S4. Weigh 200 mg of the iron-copper complex obtained in step S3, add it to 100 mL of a 25 mg / L tetracycline hydrochloride aqueous solution, adsorb it in the dark for 20 min, then irradiate it with simulated sunlight to degrade the antibiotic, and test the absorbance of the reaction solution. It is calculated that the degradation rate of tetracycline hydrochloride reaches 80%.

[0026] Example 2 A method for recycling waste ternary lithium battery positive electrode materials, comprising the following steps: S1. 1 g of waste ternary positive electrode material powder with a particle size of ≤50 mesh and 2.2 g of pyrite powder with a particle size of ≤50 mesh (the molar ratio of lithium element in waste ternary lithium battery positive electrode material to iron element in pyrite is 1:1.15) are mixed evenly, put into a porcelain boat and placed in the middle of a tubular furnace, air is introduced at a flow rate of 2 L / min, and calcined at 500° C. for 2 h to obtain 2.74 g of calcined powder; S2, the calcined powder was slurried with 50mL water to react, and the solution containing lithium, nickel, cobalt, manganese and the mixture containing iron were tested by ICP. The concentrations of lithium, nickel, cobalt and manganese in the solution were calculated, and the leaching rates of lithium, nickel, cobalt and manganese were 98.15%, 97.11%, 97.81% and 97.22% respectively; S3, weighing 0.75 g of the iron-containing mixture of step S2, adding 50 mL of 0.02 mol / L copper sulfate solution and ultrasonicating for 0.5 h, then adding sodium hydroxide to adjust the pH of the reaction system to 7.3 and continue ultrasonicating for 1 h, and then putting the liquid into a reactor for hydrothermal reaction, the reaction time is 5 h, the reaction temperature is 130 ° C, and after the reaction, centrifuging to obtain an iron-copper complex; S4. Weigh 20 mg of the iron-copper complex prepared in step S2, add the mixture to 100 mL of a 25 mg / L tetracycline hydrochloride aqueous solution, adsorb the mixture in the dark for 20 min, and then degrade the antibiotic under simulated sunlight. The absorbance of the reaction solution is tested, and the degradation rate of tetracycline hydrochloride is calculated to be 67%.

[0027] Example 3 A method for recycling waste ternary lithium battery positive electrode materials, comprising the following steps: S1. 1 g of waste ternary positive electrode material powder with a particle size of ≤50 mesh and 3 g of pyrite powder with a particle size of ≤50 mesh (the molar ratio of lithium element in waste ternary lithium battery positive electrode material to iron element in pyrite is 1:1.73) are mixed evenly, put into a porcelain boat and placed in the middle of a tubular furnace, air is introduced at a flow rate of 1 L / min, and calcined at 700° C. for 1 h to obtain 3.68 g of calcined powder; S2, the calcined powder was slurried with 50mL water to react, and the solution containing lithium, nickel, cobalt, manganese and the mixture containing iron were tested by ICP. The concentrations of lithium, nickel, cobalt and manganese in the solution were calculated. The leaching rates of lithium, nickel, cobalt and manganese were 99.61%, 98.40%, 97.87% and 97.52% respectively. S3, weighing 1.5 g of the iron-containing mixture of step S2, adding 50 mL of 0.01 mol / L copper sulfate solution and ultrasonicating for 0.5 h, then adding sodium hydroxide to adjust the pH of the reaction system to 7.5 and continue ultrasonicating for 1 h, and then putting the liquid into a reactor for hydrothermal reaction, the reaction time is 5 h, the reaction temperature is 130 ° C, and after the reaction, centrifuging to obtain an iron-copper complex; S4. Weigh 200 mg of the iron-copper complex prepared in step S2, add it to 100 mL of a 25 mg / L tetracycline hydrochloride aqueous solution, adsorb it in the dark for 20 min, and then degrade the antibiotic under simulated sunlight. The absorbance of the reaction solution is tested, and it is calculated that the degradation rate of tetracycline hydrochloride reaches 80%.

[0028] Comparative Example 1 The difference from Example 1 is that step S1 is calcined under a nitrogen environment.

[0029] The leaching rates of nickel, cobalt, manganese and lithium in this comparative example are 0.16%, 0%, 0.17% and 97.51%, respectively.

[0030] Comparative Example 2 The difference from Example 1 is that in step S1, 3.3 g of pyrite powder with a particle size of ≤50 mesh is added (the molar ratio of lithium element in the waste ternary lithium battery positive electrode material to iron element in the pyrite is 1:1.85).

[0031] The leaching rates of nickel, cobalt, manganese and lithium in this comparative example are 93.66%, 96.13%, 96.98% and 99.24%, respectively.

[0032] Comparative Example 3 The difference from Example 1 is that the concentration of the copper sulfate solution in step S3 is 0.002 mol / L.

[0033] The degradation rate of tetracycline hydrochloride in this comparative example is 24%.

[0034] Comparative Example 4 The difference from Example 1 is that sodium hydroxide is added in step S3 to adjust the pH of the reaction system to 5.

[0035] The degradation rate of tetracycline hydrochloride in this comparative example is 21%.

[0036] It can be seen from the above embodiments and comparative examples that the present invention crushes and screens the waste ternary lithium battery positive electrode material, adds the crushed and screened pyrite, and heats and calcines the reaction in an air environment to obtain solid A; solid A is slurried with water for reaction, and filtered after the reaction to obtain solid B and filtrate B; solid B is added with copper sulfate solution and ultrasonically obtains solution C; solution C is added with sodium hydroxide to adjust the pH of the reaction system and then ultrasonically obtains solution D; solution D is subjected to hydrothermal reaction and centrifuged to obtain solid C; solid C is added with a solution containing antibiotics, and after dark adsorption and light reaction, the degradation rate of antibiotics can reach 30-80%, and filtrate B can be precipitated and separated to extract nickel, cobalt, manganese, and lithium after enrichment and impurity removal, and the leaching rate of the four elements can reach more than 97%. The solid C obtained by the method is used as a catalyst for degrading antibiotics in water bodies, and the filtrate B is used to extract nickel, cobalt, manganese, and lithium after enrichment, so as to realize the resource utilization of waste ternary lithium battery positive electrode materials.

[0037] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A method for resource utilization of waste ternary lithium battery positive electrode materials, characterized in that: The steps include: S1. After the waste ternary lithium battery positive electrode material is crushed and sieved, pyrite is added, and solid A is obtained after heating and calcination reaction in an air environment; S2, solid A is slurried with water for reaction, and after the reaction, solid B and filtrate B are obtained by filtration; S3, solid B is added with copper sulfate solution and then ultrasonicated to obtain solution C; S4, adding sodium hydroxide to solution C to adjust the pH of the reaction system and then continuing ultrasonication to obtain solution D; S5, solution D is subjected to hydrothermal reaction and then centrifuged to obtain solid C; S6. Solid C is added to a solution containing antibiotics, and the antibiotics are degraded through dark adsorption and light reaction. The filtrate B is enriched and impurities are removed, and then precipitated, separated and recovered.

2. The method for resource utilization of waste ternary lithium battery positive electrode materials according to claim 1, characterized in that: In the step S1, the particle size of the powder of the waste ternary lithium battery positive electrode material after crushing and sieving is ≤50 mesh; the molar ratio of the lithium element in the waste ternary lithium battery positive electrode material after crushing and sieving to the iron element in the pyrite is 1:(1.10-1.80).

3. The method for resource utilization of waste ternary lithium battery positive electrode materials according to claim 1, characterized in that: In the step S1, a heating calcination reaction is carried out in a tubular furnace, the heating calcination reaction temperature is 400-700° C., the reaction time is 2.0-5.0 h, and the air flow rate is 1-2 L / min.

4. The method for recycling waste ternary lithium battery positive electrode materials according to claim 1, characterized in that: In step S2, the solid B includes iron oxide and carbon, and the filtrate B is a solution containing nickel, cobalt, manganese and lithium. The leaching rates of nickel, cobalt, manganese and lithium are all ≥97%. After enrichment and impurity removal, nickel, cobalt, manganese and lithium can be precipitated and separated to extract the elements.

5. The method for recycling waste ternary lithium battery positive electrode materials according to claim 1, characterized in that: In the step S3, the solid-to-liquid ratio of solid B to copper sulfate solution is (0.5-2) g / 50 mL; the concentration of copper sulfate solution is 0.01-0.1 mol / L, and the ultrasonic time is 0.5 h.

6. The method for resource utilization of waste ternary lithium battery positive electrode materials according to claim 1, characterized in that: In the step S4, sodium hydroxide is added in the form of a solution, the concentration of the sodium hydroxide solution is 0.05-1 mol / L, and the ultrasonic time is 1 hour; the pH value of the reaction system is adjusted to 7-8.

7. The method for recycling waste ternary lithium battery positive electrode materials according to claim 1, characterized in that: In step S5, the hydrothermal reaction temperature is 100-150° C., and the reaction time is 3.0-6.0 h.

8. The method for resource utilization of waste ternary lithium battery positive electrode materials according to claim 1, characterized in that: In step S5, the solid C is an iron-copper complex, which is used as a catalyst for degrading antibiotics in water to achieve resource utilization.

9. The method for resource utilization of waste ternary lithium battery positive electrode materials according to claim 1, characterized in that: In the step S6, the antibiotics are a series of electron-rich antibiotics.

10. The method for recycling waste ternary lithium battery positive electrode materials according to claim 1, characterized in that: In step S6, the degradation rate of antibiotics is 30-80%.