阅读说明：本技术 一种废旧三元锂电池正极材料回收循环利用工艺 (Recycling process of waste ternary lithium battery positive electrode material ) 是由 周明炯 刘博宇 庞宝成 于 2020-06-01 设计创作，主要内容包括：本发明提供了一种废旧三元锂电池正极材料回收循环利用工艺。本发明使用的正极片处理液,在材料成分上毒性极小,分离过程中能够有效的溶解粘结剂,使活性物质脱离出来,效率极高,溶解液易降解,对环境十分友好。另外,后续回收过程中,目前使用较多的是用有机萃取剂对有价金属进行萃取回收,使用的萃取剂对环境的污染严重,同时其萃取过程也十分复杂,本发明用的共沉淀法,避免了萃取剂的使用,直接合成前驱体也简化了回收的步骤,做到了节能环保。(The invention provides a recycling process of a waste ternary lithium battery anode material. The anode plate treating fluid used in the invention has extremely low toxicity on material components, can effectively dissolve the binder in the separation process, enables active substances to be separated out, has extremely high efficiency, is easy to degrade, and is very environment-friendly. In addition, in the subsequent recovery process, at present, organic extractant is used for extracting and recovering valuable metals, the used extractant has serious pollution to the environment, and the extraction process is very complex.)

1. A recycling process for a waste ternary lithium battery positive electrode material is characterized by comprising the following steps:

A) placing a positive plate of a waste ternary lithium battery in a treatment solution, heating and stirring, and then filtering to obtain a filtered product, wherein the treatment solution comprises a solvent and a solute, the solvent is selected from one or more of ethylene glycol, glycerol and butanediol, and the solute is selected from one or more of xylitol, glucose, urea and choline chloride;

B) screening and acid leaching the filtered product in sequence to obtain acid leaching solution;

C) adjusting the ion concentration of the pickle liquor, adding a complexing agent and a precipitator to adjust the pH value, carrying out coprecipitation reaction to separate a precursor, and then recovering the metal lithium.

2. The process as claimed in claim 1, wherein the positive plate of the waste ternary lithium battery is obtained by the following method:

soaking the waste ternary lithium battery in saturated salt water for discharging treatment;

cleaning and drying the discharged waste ternary lithium battery with clear water;

cutting and crushing the dried battery into battery slices;

and separating the positive plate, the negative plate, the shell and the diaphragm of the battery by a flotation method.

3. The process according to claim 1, wherein the battery slices have a size of 1-2 cm.

4. The process according to claim 1, wherein the molar ratio of the solute to the solvent in the treatment solution is (1.5-2.5): 1, and the solid-liquid mass-volume ratio of the positive electrode sheet to the treatment solution is 1 g: (20-25) ml.

5. The process according to claim 1, wherein the heating and stirring temperature is 150-200 ℃ and the time is 3-5 h.

6. The process according to claim 1, wherein the mass-to-volume ratio of the positive electrode active material obtained after screening to the acid solution used for acid leaching is 1 g: (5-20) ml; the acid liquor used for acid leaching is a mixed solution of inorganic acid and a reducing agent, and the inorganic acid is H₂SO₄、HCl、HNO₃The reducing agent is H₂O₂、Na₂SO₃、Na₂S₂O₃The concentration of the inorganic acid in the acid solution is 2-4 mol/L, 1-2 mL of liquid reducing agent is added into each gram of active substance, or 0.2-0.5 g of solid reducing agent is added into each gram of positive electrode active substance,

the acid leaching temperature is 60-80 ℃, and the time is 4-5 h.

7. The process of claim 1, wherein the ion concentration of the acid leaching solution is adjusted by using nickel salt, cobalt salt and manganese salt to adjust the ion concentration of nickel, cobalt and manganese in the acid leaching solution to 0.5-2 mol/L of nickel ion, 0.2-1 mol/L of cobalt ion and 0.2-1 mol/L of manganese ion.

8. The process of claim 1, wherein the complexing agent is NH₃·H₂O, NaF and ammonium salt, wherein the precipitant is one or more of sodium hydroxide, potassium hydroxide, sodium bicarbonate, sodium carbonate and potassium carbonate, and the pH of the pickle liquor is adjusted to 11-12.

9. The process according to claim 1, wherein in the step C), the reaction temperature is 50-60 ℃, the stirring speed during the reaction is 500-700 r/min, and the reaction time is 5-10 h.

10. The process of claim 1, wherein the method for recovering lithium metal is:

and adding water-soluble carbonate into the reaction solution after the reaction, so that lithium ions are precipitated as lithium carbonate.

Technical Field

The invention belongs to the technical field of new energy batteries, and particularly relates to a process for recycling a waste ternary lithium battery positive electrode material.

Background

Lithium ion batteries have many advantages of small size, light weight, high specific energy, long service life, etc., and are widely used in many fields such as electric vehicles, mobile phones, notebook computers, cameras, etc. After the lithium batteries are popularized and used, a large amount of waste lithium batteries are generated. In addition, valuable metals contained in the waste lithium batteries can be recycled, so that the problem of resource shortage of metals such as nickel, cobalt, manganese and the like can be effectively solved, the metals are recycled, the waste is changed into valuable materials, and the environmental pollution is greatly reduced while the metals are well recycled. At present, in the recovery of lithium batteries, hydrometallurgy is mainly used, valuable metals exist in a solution in an ion form through acid leaching and dissolution, and then the valuable metals are gradually extracted by using an extracting agent, so that the cost consumption of the process is high, and the use of the extracting agent can affect the environment.

Disclosure of Invention

In view of the above, the technical problem to be solved by the invention is to provide a process for recycling a waste ternary lithium battery positive electrode material, wherein the process provided by the invention is energy-saving and environment-friendly, and can effectively separate an active substance from a current collector and circularly regenerate the active substance.

The invention provides a process for recycling a waste ternary lithium battery positive electrode material, which comprises the following steps:

A) placing a positive plate of a waste ternary lithium battery in a treatment solution, heating and stirring, and then filtering to obtain a filtered product, wherein the treatment solution comprises a solvent and a solute, the solvent is selected from one or more of ethylene glycol, glycerol and butanediol, and the solute is selected from one or more of xylitol, glucose, urea and choline chloride;

B) screening and acid leaching the filtered product in sequence to obtain acid leaching solution;

C) adjusting the ion concentration of the pickle liquor, adding a complexing agent and a precipitator to adjust the pH value, carrying out coprecipitation reaction to separate a precursor, and then recovering the metal lithium.

Preferably, the positive plate of the waste ternary lithium battery is obtained by the following method:

soaking the waste ternary lithium battery in saturated salt water for discharging treatment;

cleaning and drying the discharged waste ternary lithium battery with clear water;

cutting and crushing the dried battery into battery slices;

and separating the positive plate, the negative plate, the shell and the diaphragm of the battery by a flotation method.

Preferably, the size of the battery slice is 1-2 cm.

Preferably, the molar ratio of the solute to the solvent in the treatment solution is (1.5-2.5): 1, and the solid-liquid mass-volume ratio of the positive electrode sheet to the treatment solution is 1 g: (20-25) ml.

Preferably, the heating and stirring temperature is 150-200 ℃, and the time is 3-5 h.

Preferably, the mass-to-volume ratio of the positive electrode active material obtained after screening to the acid solution used for acid leaching is 1 g: (5-20) ml; the acid liquor used for acid leaching is a mixed solution of inorganic acid and a reducing agent, and the inorganic acid is H₂SO₄、HCl、HNO₃The reducing agent is H₂O₂、Na₂SO₃、Na₂S₂O₃The concentration of the inorganic acid in the acid solution is 2-4 mol/L, 1-2 mL of liquid reducing agent is added into each gram of active substance, or 0.2-0.5 g of solid reducing agent is added into each gram of positive active substance, the acid leaching temperature is 60-80 ℃, and the time is 4-5 hours.

Preferably, the ion concentration of the acid leaching solution is adjusted by adopting nickel salt, cobalt salt and manganese salt to adjust the ion concentration of nickel, cobalt and manganese in the acid leaching solution until the concentration of nickel ions is 0.5-2 mol/L, the concentration of cobalt ions is 0.2-1 mol/L and the concentration of manganese ions is 0.2-1 mol/L.

Preferably, the complexing agent is NH₃·H₂O, NaF and ammonium salt, wherein the precipitant is one or more of sodium hydroxide, potassium hydroxide, sodium bicarbonate, sodium carbonate and potassium carbonate, and the pH of the pickle liquor is adjusted to 11-12.

Preferably, in the step C), the reaction temperature is 50-60 ℃, the stirring speed during the reaction is 500-700 r/min, and the reaction time is 5-10 h.

Preferably, the method for recovering the metallic lithium comprises the following steps:

and adding water-soluble carbonate into the reaction solution after the reaction, so that lithium ions are precipitated as lithium carbonate.

Compared with the prior art, the invention provides a process for recycling a waste ternary lithium battery anode material, which comprises the following steps: A) placing a positive plate of a waste ternary lithium battery in a treatment solution, heating and stirring, and then filtering to obtain a filtered product, wherein the treatment solution comprises a solvent and a solute, the solvent is selected from one or more of ethylene glycol, glycerol and butanediol, and the solute is selected from one or more of xylitol, glucose, urea and choline chloride; B) screening and acid leaching the filtered product in sequence to obtain acid leaching solution; C) and after the pH value and the ion concentration of the pickle liquor are adjusted, adding a complexing agent and a precipitator for reaction, and recovering the lithium metal. The anode plate treating fluid used in the invention has extremely low toxicity on material components, can effectively dissolve the binder in the separation process, enables active substances to be separated out, has extremely high efficiency, is easy to degrade, and is very environment-friendly. In addition, in the subsequent recovery process, at present, organic extractant is used for extracting and recovering valuable metals, the used extractant has serious pollution to the environment, and the extraction process is very complex.

Drawings

FIG. 1 is a process flow chart of the recycling process of the anode material of the waste ternary lithium battery provided by the invention.

Detailed Description

The invention provides a process for recycling a waste ternary lithium battery positive electrode material, which comprises the following steps:

A) placing the positive plate of the waste ternary lithium battery in a treatment solution, heating and stirring, and then filtering to obtain a filtered product; the processing liquid comprises a solvent and a solute, wherein the solvent is selected from one or more of ethylene glycol, glycerol and butanediol, and the solute is selected from one or more of xylitol, glucose, urea and choline chloride;

B) screening and acid leaching the filtered product in sequence to obtain acid leaching solution;

C) and after the pH value and the ion concentration of the pickle liquor are adjusted, adding a complexing agent and a precipitator for reaction, and recovering the lithium metal.

The invention firstly separates the positive plate from the waste ternary lithium battery, and the specific method comprises the following steps:

soaking the waste ternary lithium battery in saturated salt water for discharging treatment;

cleaning and drying the discharged waste ternary lithium battery with clear water;

cutting and crushing the dried battery into battery slices, wherein the size of each battery slice is 1-2 cm;

the positive plate, the negative plate, the shell and the diaphragm of the battery are separated by a flotation method, and the specific method of the flotation method is not particularly limited, and can be a method known by a person skilled in the art.

And after obtaining the positive plate, placing the positive plate in a treatment solution for heating and stirring treatment.

The processing liquid comprises a solvent and a solute, wherein the solvent is selected from one or more of ethylene glycol, glycerol and butanediol, and the solute is selected from one or more of xylitol, glucose, urea and choline chloride. In some embodiments of the invention, the treatment fluid is a mixture of choline chloride and butylene glycol. The molar ratio of the solute to the solvent in the treatment liquid is (1.5-2.5): 1.

In the invention, the solid-liquid mass volume ratio of the positive plate to the treatment solution is 1 g: (20-25) ml.

In the invention, the solid-liquid mass-volume ratio is as follows: and ml is taken as a unit.

The heating and stirring temperature is 150-200 ℃, preferably 160-190 ℃, and the time is 3-5 h, preferably 3.5-4.5 h.

And after the heating and stirring treatment is finished, filtering, screening filter residues, and separating a larger aluminum foil from the positive active material.

And performing acid leaching on the positive electrode active substance to obtain acid leaching solution.

Wherein the mass-to-volume ratio of the anode active material obtained after screening to the acid solution used for acid leaching is 1 g: (5-20) ml; preferably 1 g: 10 ml; the acid liquor used for acid leaching is a mixed solution of inorganic acid and a reducing agent, and the inorganic acid is H₂SO₄、HCl、HNO₃The reducing agent is H₂O₂、Na₂SO₃、Na₂S₂O₃The concentration of the inorganic acid in the acid solution is 2-4 mol/L, preferably 2.5-3.5 mol/L, 1-2 mL of liquid reducing agent is added into each gram of positive electrode active substance, or 0.2-0.5 g of solid reducing agent is added into each gram of positive electrode active substance,

the acid leaching temperature is 60-80 ℃, preferably 65-75 ℃, and the time is 4-5 h.

After the acid leaching solution is obtained, adjusting the ion concentration of the acid leaching solution, namely adjusting the ion concentration of nickel, cobalt and manganese in the acid leaching solution by adopting nickel salt, cobalt salt and manganese salt until the nickel ion concentration is 0.5-2 mol/L, preferably 1mol/L, the cobalt ion concentration is 0.2-1 mol/L, preferably 0.6mol/L, and the manganese ion concentration is 0.2-1 mol/L, preferably 0.4 mol/L.

And then, adding a complexing agent and a precipitator to adjust the pH value for coprecipitation reaction. Wherein the complexing agent is NH₃·H₂O, NaF and ammonium salt, wherein the precipitant is one or more of sodium hydroxide, potassium hydroxide, sodium bicarbonate, sodium carbonate and potassium carbonate, and the pH of the solution is adjusted to 11-12.

And (3) carrying out coprecipitation reaction to generate a precursor, and washing and drying the precursor. Recovering metallic lithium from reaction liquid obtained after coprecipitation reaction, and the specific method comprises the following steps:

a water-soluble carbonate, preferably sodium carbonate or potassium carbonate, is added to the reaction solution after the reaction, so that lithium ions are precipitated as lithium carbonate.

Referring to fig. 1, fig. 1 is a flow chart of a process for recycling the anode material of the waste ternary lithium battery provided by the invention.

In the separation of active substances, high-temperature ignition and NMP and DMF solvent dissolution are commonly used at present, the former has high energy consumption and high risk, and the latter has high solvent toxicity. In the subsequent recovery process, at present, organic extractant is used for extracting and recovering valuable metals, the used extractant has serious pollution to the environment, and the extraction process is very complicated.

For further understanding of the present invention, the following describes a recycling process of the waste ternary lithium battery positive electrode material provided by the present invention with reference to the following examples, and the scope of the present invention is not limited by the following examples.