CN104600391A - Method for preparing manganese-doped cobalt ferrite magnetostriction material by utilizing spent lithium ion batteries - Google Patents

Abstract

The invention discloses a method for preparing a manganese-doped cobalt ferrite magnetostrictive material by utilizing waste lithium ion batteries, and belongs to the technical field of waste lithium ion battery recycling and preparation of magnetostrictive materials. The key points of the technical solution of the present invention are: the method for preparing manganese-doped cobalt ferrite magnetostrictive material by using waste lithium ion batteries, and using waste lithium ion batteries to prepare Manganese-doped cobalt ferrite magnetostrictive material with high magnetostrictive performance. The invention realizes the recycling of waste lithium-ion batteries, not only saves energy but also protects the environment. The manganese-doped cobalt ferrite magnetostrictive material has high magnetostrictive performance under low field, and can be used in pressure sensors, Notable applications are in actuators, non-contact sensors, sonar exploration, and magnetic ejection devices.

Description

Method for preparing manganese-doped cobalt ferrite magnetostrictive material using waste lithium ion battery

technical field

The invention belongs to the technical field of recycling of waste lithium ion batteries and preparation of magnetostrictive materials, and in particular relates to a method for preparing manganese-doped cobalt ferrite magnetostrictive materials by using waste lithium ion batteries.

Background technique

Lithium-ion batteries have a series of excellent properties, and have the advantages of high specific energy, high power density, high working voltage and long cycle life. They have been widely used in mobile phones, notebook computers and cameras, etc. Developed with electric tools, the market share increased significantly. At present, the cathode materials of lithium ion batteries mainly include LiMO ₂ (LiCoO ₂ , LiNiO ₂ , LiNi _1/3 Co _1/3 Mn _1/3 O ₂ ) system, lithium manganese oxide (LiMn ₂ O ₄ ) system and iron lithium system ( LiFePO ₄ ) system.

Waste lithium-ion batteries are a common solid waste in daily life. With the progress of life and the rapid development of science and technology, the amount of waste is increasing year by year. Waste lithium-ion batteries contain a large amount of metals such as cobalt, lithium and iron. Not only It will cause serious pollution to the environment such as water and air, and will cause a lot of waste of resources. Therefore, it is necessary to recycle waste lithium-ion batteries. At present, many researchers have done a lot of work on the recycling of waste lithium-ion batteries. On the one hand, in the traditional resource recovery, the precious metals in waste lithium-ion batteries are mainly separated and purified, and reused as industrial raw materials; On the one hand, the waste lithium-ion batteries are crushed and leached with acid solution, and the metals in them are directly used to make some value-added products, such as metal sulfates, nitrates, etc., and recombined into lithium cobalt oxide and other composite functional materials. materials, and the method of using waste lithium-ion batteries to prepare magnetostrictive materials has not been reported.

Contents of the invention

The purpose of the present invention is to provide a method for preparing manganese-doped cobalt ferrite magnetostrictive materials by using waste lithium-ion batteries, through the method of sol-gel-hydrothermal coupling, using waste lithium-ion batteries to prepare Manganese-doped cobalt ferrite magnetostrictive material with high magnetostrictive performance.

In order to achieve the above object, the present invention adopts the following technical scheme, utilizes the waste and old lithium ion battery to prepare the method for manganese-doped cobalt ferrite magnetostrictive material, is characterized in that comprising the following steps:

(1) Select the waste lithium-ion battery with lithium cobaltate and lithium iron phosphate as the positive electrode material, and disassemble the waste lithium-ion battery to obtain the positive electrode active material and sulfuric acid/hydrogen peroxide mixed solution according to the solid-liquid ratio of 1:2-6g/mL For leaching, filter the leaching solution and adjust pH=9-10 with sodium hydroxide, completely precipitate Fe ³⁺ and Co ²⁺ in the filtrate, filter and wash the filter residue with deionized water, then dissolve and filter out incompatible substances with nitric acid ;

(2) Measure the content of Fe ³⁺ and Co ²⁺ in the filtered nitric acid solution with an atomic absorption spectrophotometer, and use Co(NO ₃ ) ₂ ·6H ₂ O and Co(NO ₃ ) ₂ ·6H ₂ O Or Fe(NO ₃ ) ₃ .9H ₂ O adjusts the molar ratio of Fe ³⁺ to Co ²⁺ and Mn ²⁺ in the solution to be 2:1, and the molar ratio of Mn ²⁺ to Co ²⁺ is X: 1-X, X=0.1-0.4, then heat in a water bath at 80°C, add citric acid to the solution, wherein the molar ratio of citric acid to the total molar mass of Fe ³⁺ , Co ²⁺ and Mn ²⁺ is 1:1 , adjust the pH of the solution to 5-7, heat the solution in a water bath at 80°C until the solution is gel-like, dry the gel at 120°C until it becomes dry, and then conduct a self-propagating treatment at 200°C for 2 hours to obtain a precursor. Put it into a reaction kettle and add deionized water, react hydrothermally at 140-200°C, filter, wash and dry the reaction product to obtain manganese-doped cobalt ferrite powder;

(3) Add polyvinyl alcohol binder with a mass concentration of 8%-10% of 3%-5% of the mass of manganese-doped cobalt ferrite powder to the manganese-doped cobalt ferrite powder, and grind to make the manganese-doped Mix cobalt ferrite powder and polyvinyl alcohol binder evenly, then granulate through 80-120 mesh sieve, add the granulated mixture into a mold with a diameter of 10mm, and press it under a pressure of 10-15MPa to form 10mm*20mm cylindrical sample body;

(4) Heat the cylindrical sample body at 100°C for 60 minutes to remove moisture, then cool it down to room temperature naturally, then raise the temperature to 600-650°C at a heating rate of 5°C/min in the muffle furnace and keep it for 360 minutes to remove the polyvinyl alcohol bond After the furnace temperature drops to room temperature, the temperature is raised to 1300-1500°C at a rate of 5°C/min in the high-temperature furnace and kept for 10-60min for calcination, and the manganese doped with smooth surface is obtained as the furnace temperature drops to room temperature. Cobalt-doped ferrite magnetostrictive material.

Further preferably, the molar concentration of sulfuric acid in the sulfuric acid/hydrogen peroxide mixed solution in step (1) is 2-4mol/L, and the mass ratio of the volume of hydrogen peroxide with a mass concentration of 30% to the positive electrode active material is 0.5-1.5:1mL/g . In step (1), filter the leaching solution and adjust the pH to 9.5 with sodium hydroxide.

The invention has the following beneficial effects: (1) Recycling of waste lithium-ion batteries not only saves energy but also protects the environment; (2) The prepared manganese-doped cobalt ferrite magnetostrictive material has a high Magnetostrictive properties have notable applications in pressure sensors, brakes, non-contact sensors, sonar exploration, and magnetic ejection devices.

Detailed ways

The above content of the present invention will be described in further detail below through the embodiments, but this should not be interpreted as the scope of the above subject of the present invention is limited to the following embodiments, all technologies realized based on the above content of the present invention all belong to the scope of the present invention.

Example 1

(1) Select the waste lithium-ion battery with lithium cobalt oxide and lithium iron phosphate as the positive electrode material, and leaching the positive electrode active material obtained by dismantling the waste lithium-ion battery with the mixed solution of sulfuric acid/hydrogen peroxide at a solid-to-liquid ratio of 1:4g/mL , after filtering the leaching solution, adjust the pH=9.5 with sodium hydroxide, completely precipitate Fe ³⁺ and Co ²⁺ in the filtrate, filter and wash the filter residue with deionized water, then dissolve it with nitric acid and filter out incompatible substances, sulfuric acid/hydrogen peroxide The molar concentration of sulfuric acid in the mixed solution is 3mol/L, and the mass ratio of the volume of hydrogen peroxide with a mass concentration of 30% to the positive electrode active material is 1:1mL/g;

(2) Measure the content of Fe ³⁺ and Co ²⁺ in the filtered nitric acid solution with an atomic absorption spectrophotometer, and use Co(NO ₃ ) ₂ ·6H ₂ O and Co(NO ₃ ) ₂ ·6H ₂ O Or Fe(NO ₃ ) ₃ .9H ₂ O adjusts the molar ratio of Fe ³⁺ to the total molar weight of Co ²⁺ and Mn ²⁺ in the solution to be 2:1, and the molar ratio of Mn ²⁺ to Co ²⁺ is 3: 7. Then heat in a water bath at 80°C, add citric acid to the solution, wherein the molar ratio of citric acid to the total molar mass of Fe ³⁺ , Co ²⁺ and Mn ²⁺ is 1:1, adjust the pH of the solution to 6, Heat it in a water bath at 80°C until the solution is gel-like, dry the gel at 120°C until it becomes dry, and then conduct a self-propagating treatment at 200°C for 2 hours to obtain a precursor. Put the precursor into the reaction kettle and add deionized water , hydrothermal reaction at 180°C, the reaction product was filtered, washed, and dried to obtain manganese-doped cobalt ferrite powder;

(3) Add 4% of the manganese-doped cobalt ferrite powder mass concentration of polyvinyl alcohol binder with a mass concentration of 9% in the manganese-doped cobalt ferrite powder, and grind the manganese-doped cobalt ferrite powder Mix evenly with polyvinyl alcohol binder, then granulate through a 100-mesh sieve, add the granulated mixture to a mold with a diameter of 10mm, and press it under a pressure of 12MPa to form a cylindrical sample body of 10mm*20mm;

(4) The cylindrical sample body was kept at 100°C for 60 minutes to remove moisture, then cooled to room temperature naturally, and then heated to 620°C at a heating rate of 5°C/min in the muffle furnace and kept for 360 minutes to remove the polyvinyl alcohol binder As the furnace temperature drops to room temperature, finally raise the temperature to 1400°C in a high-temperature furnace at a heating rate of 5°C/min and hold for 30 minutes for calcination. As the furnace temperature drops to room temperature, a manganese-doped cobalt ferrite magnet with a smooth surface is produced. stretchable material.

Example 2

(1) Select the waste lithium-ion battery with lithium cobalt oxide and lithium iron phosphate as the positive electrode material, and leaching the positive electrode active material obtained by dismantling the waste lithium-ion battery with the mixed solution of sulfuric acid/hydrogen peroxide at a solid-to-liquid ratio of 1:2g/mL , after filtering the leaching solution, adjust the pH=9 with sodium hydroxide, completely precipitate Fe ³⁺ and Co ²⁺ in the filtrate, filter and wash the filter residue with deionized water, then dissolve it with nitric acid and filter out incompatible substances, sulfuric acid/hydrogen peroxide The molar concentration of sulfuric acid in the mixed solution is 2mol/L, and the mass ratio of the volume of hydrogen peroxide with a mass concentration of 30% to the positive electrode active material is 0.5:1mL/g;

(2) Measure the content of Fe ³⁺ and Co ²⁺ in the filtered nitric acid solution with an atomic absorption spectrophotometer, and use Co(NO ₃ ) ₂ ·6H ₂ O and Co(NO ₃ ) ₂ ·6H ₂ O Or Fe(NO ₃ ) ₃ 9H ₂ O to adjust the molar ratio of Fe ³⁺ to Co ²⁺ and Mn ²⁺ in the solution to be 2:1, and the molar ratio of Mn ²⁺ to Co ²⁺ to be 1: 9. Then heat in a water bath at 80°C, add citric acid to the solution, wherein the molar ratio of citric acid to the total molar mass of Fe ³⁺ , Co ²⁺ and Mn ²⁺ is 1:1, adjust the pH of the solution to 5, Heat it in a water bath at 80°C until the solution is gel-like, dry the gel at 120°C until it becomes dry, and then conduct a self-propagating treatment at 200°C for 2 hours to obtain a precursor. Put the precursor into the reaction kettle and add deionized water , hydrothermal reaction at 140°C, the reaction product was filtered, washed, and dried to obtain manganese-doped cobalt ferrite powder;

(3) Add 3% of the manganese-doped cobalt ferrite powder mass concentration of polyvinyl alcohol binder with a mass concentration of 8% in the manganese-doped cobalt ferrite powder, and grind the manganese-doped cobalt ferrite powder Mix evenly with polyvinyl alcohol binder, then granulate through 80-mesh sieve, add the granulated mixture into a mold with a diameter of 10mm, and press it under a pressure of 10MPa to form a cylindrical sample body of 10mm*20mm;

(4) The cylindrical sample body was kept at 100°C for 60 minutes to remove moisture, then cooled to room temperature naturally, and then heated to 600°C at a heating rate of 5°C/min in the muffle furnace and kept for 360 minutes to remove the polyvinyl alcohol binder As the furnace temperature drops to room temperature, finally raise the temperature to 1300°C at a heating rate of 5°C/min in a high-temperature furnace and keep it for 10 minutes for calcination. As the furnace temperature drops to room temperature, manganese-doped cobalt ferrite magnets with smooth and flat surfaces are produced. stretchable material.

Example 3

(1) Select the waste lithium-ion battery with lithium cobalt oxide and lithium iron phosphate as the positive electrode material, and leaching the positive electrode active material obtained by dismantling the waste lithium-ion battery with the mixed solution of sulfuric acid/hydrogen peroxide at a solid-to-liquid ratio of 1:6g/mL , after filtering the leaching solution, adjust the pH=10 with sodium hydroxide, completely precipitate Fe ³⁺ and Co ²⁺ in the filtrate, filter and wash the filter residue with deionized water, then dissolve it with nitric acid and filter out incompatible substances, sulfuric acid/hydrogen peroxide The molar concentration of sulfuric acid in the mixed solution is 4mol/L, and the mass ratio of the volume of hydrogen peroxide with a mass concentration of 30% to the positive electrode active material is 1.5:1mL/g;

(2) Measure the content of Fe ³⁺ and Co ²⁺ in the filtered nitric acid solution with an atomic absorption spectrophotometer, and use Co(NO ₃ ) ₂ ·6H ₂ O and Co(NO ₃ ) ₂ ·6H ₂ O Or Fe(NO ₃ ) ₃ .9H ₂ O adjusts the molar ratio of Fe ³⁺ to the total molar weight of Co ²⁺ and Mn ²⁺ in the solution to be 2:1, and the molar ratio of Mn ²⁺ to Co ²⁺ is 2: 3. Then heat in a water bath at 80°C, add citric acid to the solution, wherein the molar ratio of citric acid to the total molar mass of Fe ³⁺ , Co ²⁺ and Mn ²⁺ is 1:1, adjust the pH of the solution to 7, Heat it in a water bath at 80°C until the solution is gel-like, dry the gel at 120°C until it becomes dry, and then conduct a self-propagating treatment at 200°C for 2 hours to obtain a precursor. Put the precursor into the reaction kettle and add deionized water , hydrothermal reaction at 200°C, the reaction product was filtered, washed, and dried to obtain manganese-doped cobalt ferrite powder;

(3) Add 5% of the manganese-doped cobalt ferrite powder mass concentration of polyvinyl alcohol binder with a mass concentration of 10% in the manganese-doped cobalt ferrite powder, and grind the manganese-doped cobalt ferrite powder Mix evenly with polyvinyl alcohol binder, then granulate through a 120-mesh sieve, add the granulated mixture to a mold with a diameter of 10mm, and press it under a pressure of 15MPa to form a cylindrical sample body of 10mm*20mm;

(4) The cylindrical sample body was kept at 100°C for 60 minutes to remove moisture, then cooled to room temperature naturally, and then heated to 650°C at a heating rate of 5°C/min in the muffle furnace and kept for 360 minutes to remove the polyvinyl alcohol binder As the furnace temperature drops to room temperature, finally raise the temperature to 1500°C at a heating rate of 5°C/min in a high-temperature furnace and keep it for 60 minutes for calcination. As the furnace temperature drops to room temperature, a manganese-doped cobalt ferrite magnet with a smooth surface is obtained. stretchable material.

The above embodiments describe the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above-mentioned embodiments, and that described in the above-mentioned embodiments and the specification only illustrates the principle of the present invention, and the present invention also has various aspects without departing from the scope of the principle of the present invention. Changes and improvements, these changes and improvements all fall within the protection scope of the present invention.

Claims (3)

1. utilize waste and old lithium ion battery to prepare the method for additive Mn Conjugate ferrite magnetostrictive material, it is characterized in that comprising the following steps:

(1) select with cobalt acid lithium and the LiFePO4 waste and old lithium ion battery that is positive electrode, waste and old lithium ion battery is split the positive electrode active materials obtained and sulfuric acid/hydrogen peroxide mixed solution leaches by solid-to-liquid ratio 1:2-6g/mL, pH=9-10 is regulated with NaOH, the Fe in complete precipitation filtrates after being filtered by leaching liquid ³⁺and Co ²⁺, filter and use washed with de-ionized water filter residue, then with nitric acid dissolve and elimination is not tolerant;

(2) Fe in the nitric acid dissolve liquid after filtering is measured with atomic absorption spectrophotometer ³⁺and Co ²⁺content, and with Co (NO ₃) ₂6H ₂o and Co (NO ₃) ₂6H ₂o or Fe (NO ₃) ₃9H ₂o regulates Fe in lysate ³⁺with Co ²⁺and Mn ²⁺the mol ratio of integral molar quantity is 2:1, Mn ²⁺with Co ²⁺mol ratio be X:1-X, X=0.1-0.4, then in 80 DEG C of heating water baths, in lysate, add citric acid, wherein citric acid and Fe ³⁺, Co ²⁺and Mn ²⁺the mol ratio of integral molar quantity is 1:1, regulate the pH=5-7 of solution, in 80 DEG C of water-baths, be heated to lysate is gel, presoma is obtained at 200 DEG C of self-propagating process 2h after gel is dried to xerogel in 120 DEG C, presoma is put into reactor and adds deionized water, in 140-200 DEG C of hydro-thermal reaction, product filtration, washing, drying obtain additive Mn cobalt ferrite powder;

(3) mass concentration dripping additive Mn cobalt ferrite powder quality 3%-5% in additive Mn cobalt ferrite powder is the polyvinyl alcohol adhesive of 8%-10%, grinding makes additive Mn cobalt ferrite powder mix with polyvinyl alcohol adhesive, then the granulation of 80-120 mesh sieve is crossed, mixture after granulation being added to diameter is in the mould of 10mm, makes the cylindrical sample base substrate of 10mm*20mm in the pressure of 10-15MPa;

(4) cylindrical sample base substrate is naturally cooled to room temperature after 100 DEG C of insulation 60min remove moisture, then in Muffle furnace, be warming up to 600-650 DEG C with the heating rate of 5 DEG C/min and be incubated after 360min removes polyvinyl alcohol adhesive and be down to room temperature with furnace temperature, finally in high temperature furnace, be warming up to 1300-1500 DEG C with the heating rate of 5 DEG C/min and be incubated 10-60min calcining, being down to the room temperature additive Mn Conjugate ferrite magnetostrictive material that namely obtained smooth surface is smooth with furnace temperature.

2. the method utilizing waste and old lithium ion battery to prepare additive Mn Conjugate ferrite magnetostrictive material according to claim 1, it is characterized in that: in step (1) sulfuric acid/hydrogen peroxide mixed solution, the molar concentration of sulfuric acid is 2-4mol/L, mass concentration is the volume of the hydrogen peroxide of 30% and the mass ratio of positive electrode active materials is 0.5-1.5:1mL/g.

3. the method utilizing waste and old lithium ion battery to prepare additive Mn Conjugate ferrite magnetostrictive material according to claim 1, is characterized in that: regulate pH=9.5 with NaOH after being filtered by leaching liquid in step (1).