KR102561212B1 - Preparing method of complex sulphate soultion from waste electrode material of lithium ion secondary batteries - Google Patents

Abstract

The present invention includes the steps of (S10) leaching and filtering the waste electrode material of the lithium ion secondary battery with a first acidic solution; (S20) adding process sludge or process sludge and a first basic solution to the filtrate separated in step (S10) to perform primary hydrolysis to separate metallic impurities; (S30) adding a second basic solution to the filtrate separated in step (S20) to perform secondary hydrolysis to separate lithium, obtain a first cake, and separate the supernatant; (S40) adding the first cake separated in step (S30) to the filtrate in step (S20); (S50) A filter press (F/P) process is performed on the supernatant separated in step (S30) to remove nickel (Ni), cobalt (Co), and manganese (Mn) present in the supernatant. Obtaining 2 cakes; and (S60) leaching and filtering the second cake separated in step (S50) with a second acidic solution, wherein the process sludge includes the first cake. It relates to a method for preparing a complex sulfate solution from an electrode material.

Description

Method for producing composite sulfate solution from waste electrode material of lithium ion secondary battery

The present invention relates to a method for preparing a composite sulfate solution from waste electrode materials of a lithium ion secondary battery, and more specifically, to reuse a process sludge generated in the process of preparing the solution, and to obtain a basic solution and nickel (Ni), cobalt (Co) and It relates to a method for minimizing the loss rate of manganese (Mn).

A battery converts chemical energy into electrical energy through an electrochemical reaction, and recently generates electrical energy through reversible intercalation and deintercalation of lithium ions in cathode and anode materials. The amount of lithium ion secondary batteries used is increasing.

The cathode material of a lithium ion secondary battery is based on lithium (Li), which is a source of lithium ions, nickel (Ni), which increases the capacity of the secondary battery, cobalt (Co), which improves the capacity and cycle stability of the secondary battery, and secondary battery It is possible to use a multi-element metal and its oxide further containing a metal such as manganese (Mn), which improves the stability and economy of. Recently, ternary materials (NCM) of nickel, cobalt, and manganese are mainly used. A large amount of nickel and manganese reduces the lifespan of the cathode material, and cobalt is a metal included in the cathode material because the price is high and the entire amount is imported. Various attempts have been made to manufacture a secondary battery cathode material having high stability and capacity by adjusting the content and mixing ratio of elements.

On the other hand, as the emission of lithium ion secondary batteries is rapidly increasing due to explosive demand for lithium ion secondary batteries and shortened use cycles of small digital home appliances, domestic and foreign interest in the treatment and recycling of lithium ion secondary batteries is increasing. When the life of such a lithium ion secondary battery is over, if the waste material is used, not only can problems such as environmental pollution be reduced, but also the cost of raw materials during production of the lithium ion secondary battery can be reduced. In addition, since defects generated during the manufacturing process of lithium ion secondary batteries or waste electrode materials discharged after use contain valuable metals such as nickel, cobalt, and manganese, technology development to recover and recycle these useful resources This is actively underway.

Recently, a method of preparing a ternary composite sulfate solution containing nickel, cobalt, and manganese by removing metal impurities contained in the waste electrode material by leaching the waste electrode material with acid and hydrolyzing the waste electrode material has been used. The method shows process cost and cost reduction effect by simultaneously recycling nickel, cobalt, and manganese without separate separation. Subsidiary materials used in the method include an acid for acid leaching, a reducing agent for increasing the efficiency of the acid leaching, and a basic solution used in the hydrolysis process. Research is being conducted for savings. In addition, despite the above method, since valuable metals are also lost in the process of precipitation and filtration of metallic impurities through acid leaching and hydrolysis, research on ways to reduce the loss rate of valuable metals continues.

Korean Patent Registration No. 10-2228192 Korean Patent Registration No. 10-2332755

An object of the present invention is to provide a method for recycling waste electrode materials of a lithium ion secondary battery, and a method for preparing a composite sulfate solution of nickel, cobalt, and manganese from the waste electrode materials.

In addition, an object of the present invention is to provide a precursor for a lithium ion secondary battery electrode material using the complex sulfate solution and a method for manufacturing a lithium ion secondary battery including the same.

A method for preparing a composite sulfate solution from waste electrode material of a lithium ion secondary battery according to an aspect of the present invention includes the steps of (S10) leaching and filtering the waste electrode material of a lithium ion secondary battery with a first acidic solution, (S20 ) Separating metal impurities by adding process sludge or process sludge and a first basic solution to the filtrate separated in the step (S10) to perform primary hydrolysis, (S30) the separated metal impurities in the step (S20) Adding a second basic solution to the filtrate to perform secondary hydrolysis to separate lithium, obtaining a first cake, and separating the supernatant, (S40) the first cake separated in the step (S30) as described above Adding to the filtrate of step (S20), (S50) performing a filter press (F/P) process on the supernatant separated in step (S30) to remove nickel (Ni) and cobalt present in the supernatant Obtaining a second cake containing (Co) and manganese (Mn), and (S60) leaching the second cake separated in step (S50) with a second acidic solution and filtering, The process sludge is what contains the first cake.

Specifically, the first acidic solution includes hydrochloric acid, nitric acid, or sulfuric acid, and the filtrate separated in step (S10) may have a pH ranging from 0.5 to 1.0.

Specifically, the first acidic solution may further include one or more reducing agents selected from the group consisting of hydrogen peroxide, hydrogen sulfide, and sulfur dioxide.

Specifically, the metal impurity may include iron (Fe), aluminum (Al), and copper (Cu).

Specifically, the first basic solution and the second basic solution include an aqueous sodium carbonate solution, and the sodium carbonate aqueous solution may have a sodium carbonate content of 10 to 25% by weight based on the total weight of the sodium carbonate aqueous solution.

Specifically, in the step (S40), the first cake is added to the filtrate separated in the step (S10), and in the step (S20), the first basic solution is added to the filtrate to which the first cake is added. may be adding.

Specifically, in the step (S40), the first cake may be added to the filtrate separated in the step (S10) to adjust the filtrate to a pH in the range of 2.0 to 3.5.

Specifically, the step (S20) may be to adjust the filtrate to a pH in the range of 4.0 to 4.8 by adding the first basic solution to the filtrate to which the first cake is added.

Specifically, the second acidic solution includes a sulfuric acid solution, and the complex sulfate solution may be a nickel (Ni)-cobalt (Co)-manganese (Mn) complex sulfate solution.

Specifically, when preparing the complex sulfate solution, the total loss rate of nickel, cobalt, and manganese may be less than 3%.

A precursor for a lithium ion secondary battery electrode material according to another aspect of the present invention is prepared using a complex sulfate solution prepared by the method according to the aspect.

A method for manufacturing a lithium ion secondary battery according to another aspect of the present invention includes preparing a composite sulfate solution prepared by the method according to the aspect, preparing a precursor for an electrode material using the composite sulfate solution, and manufacturing a lithium ion secondary battery using the precursor for an electrode material.

According to the present invention, it is possible to prepare a composite sulfate solution containing a valuable metal for reusing and removing metallic impurities from waste electrode materials of a lithium ion secondary battery.

In addition, the method for producing a composite sulfate solution from waste electrode materials of a lithium ion secondary battery according to the present invention reduces the amount of basic solution used as a subsidiary material through the reuse of sludge generated in the process, and at the same time, nickel, a valuable metal , the loss rate of cobalt and manganese can be reduced compared to the existing ones.

1 is a flow chart showing a method for preparing complex sulfates according to the prior art.
Figure 2 is a flow chart showing a method for preparing a complex sulfate according to an embodiment of the present invention.

Hereinafter, each configuration of the present invention will be described in more detail so that those skilled in the art can easily practice it, but this is only one example, and the scope of the present invention is Not limited.

As used herein, the term "comprising" is used when listing materials, compositions, devices, and methods useful in the present invention and is not limited to the examples listed.

In the present invention, "valuable metals" are metals recovered from waste electrode materials of lithium ion secondary batteries and recycled to manufacture precursors for secondary battery electrode materials, and include nickel (Ni), cobalt (Co), and manganese (Mn), "Complex sulphate solution" means a sulphate solution of the above three metals.

1 is a flowchart illustrating a method for preparing a nickel (Ni)-cobalt (Co)-manganese (Mn) composite sulfate solution from a waste electrode material for a lithium ion secondary battery according to the prior art.

Referring to FIG. 1, a conventional method for producing a complex sulfate solution includes (S1) primary acid leaching and filtering of waste electrode material of a lithium ion secondary battery, (S2) the filtrate separated in the step (S1). (S3) secondary hydrolysis of the filtrate separated in step (S2) to separate lithium, (S4) supernatant separated in step (S3) filtering to obtain a cake, and (S5) secondary acid leaching of the cake to prepare a complex sulfate solution.

In step (S4) of the method, the supernatant of step (S3) may be subjected to a filter press (F/P) process to obtain a cake containing nickel, cobalt, and manganese contained in the supernatant. An attempt was made to additionally recover valuable metals by supplying the cake to step (S1) and repeating the process of acid leaching.

2 is a flowchart illustrating a method of preparing a composite sulfate solution from a waste electrode material of a lithium ion secondary battery according to an embodiment of the present invention. Referring to FIG. 2 , the method for preparing a composite sulfate solution from a waste electrode material of a lithium ion secondary battery according to the present embodiment may include the following steps.

(S10) Step: Leaching and filtering the waste electrode material of the lithium ion secondary battery with a first acidic solution

The waste electrode material of the lithium ion secondary battery may use both a waste cathode material and a waste anode material, and preferably may include a waste cathode material. The waste electrode material may further include metal impurities such as aluminum (Al), iron (Fe), and copper (Cu) in addition to lithium, nickel, cobalt, and manganese, which are the main materials constituting the cathode material.

Step (S10) may be a primary acid leach step of inputting the waste electrode material of the lithium ion secondary battery into a reaction tank containing a first acid solution to obtain an acid leachate, and filtering the acid leachate to separate the filtrate. The first acidic solution may include hydrochloric acid (HCl), nitric acid (HNO ₃ ), or sulfuric acid (H ₂ SO ₄ ), preferably hydrochloric acid. The filtrate may include nickel, cobalt, and manganese, and aluminum, iron, copper, and the like as metal impurities.

Leaching and filtrate using the first acidic solution may have a pH in the range of 0.5 to 1.0, and if the pH is out of the range, the recovery rate of valuable metals is significantly lowered or the leaching efficiency of the valuable metals is higher compared to the input amount of the acidic solution. may not increase further. The pH of the leaching solution and the filtrate using the first acidic solution may be preferably 0.5 to 0.8.

The first acid solution may further include a reducing agent to increase acid leaching efficiency of the waste electrode material, and the reducing agent may include hydrogen peroxide (H ₂ O ₂ ), hydrogen sulfide (H ₂ S), and sulfur dioxide (SO ₂ ). It may be one or more selected from the group consisting of, preferably hydrogen peroxide. The reducing agent reduces metal ions, and it is known that the leaching efficiency of the reduced metal ions is relatively better in terms of reaction kinetics. Even when the first acidic solution includes the reducing agent, the leaching and filtrate using the first acidic solution preferably has a pH in the range of 0.5 to 1.0. Leaching using the first acidic solution may be performed at 75 to 85° C. for 180 to 300 minutes, and the amount of acid and reducing agent included in the first acidic solution may be adjusted to satisfy a pH within the above range.

In the step (S10), the leaching efficiency can be maximized by adjusting the concentration and input rate of the reducing agent in order to remove the chemical resistance caused by the carbon and binder added in the electrode material manufacturing process. In the process of manufacturing electrode materials for lithium ion secondary batteries, complex processes such as firing, addition of carbon and other metal oxides, and thermal fusion after adding a binder are required to maintain or improve battery characteristics. The electrode material has chemical resistance, which may act as an obstacle in recovering valuable metals by acid leaching.

For example, when hydrogen peroxide is used as a reducing agent in the acid leaching process, chemical resistance of the waste electrode material can be eliminated by supplying hydrogen peroxide at a constant concentration and at a constant rate. Hydrogen peroxide can act not only as a reduction of metal ions but also as an oxidizing agent that decomposes organic compounds such as chemically resistant binders. For this reason, the recovery rate of valuable metals can be increased by adjusting the concentration of hydrogen peroxide to 10 to 35% by weight in the aqueous solution at the time of acid leaching and introducing it at 0.1 to 5 LPM (Liter Per Minute). However, a significant amount of hydrogen peroxide introduced under a high temperature (85±5° C.) to maintain the leaching reaction is decomposed into H ₂ O or OH radicals before the redox reaction. Therefore, the input of hydrogen peroxide can recover valuable metals with high efficiency only when hydrogen peroxide of a certain concentration is introduced at a constant rate throughout the acid leaching process.

Step (S20): Separating metal impurities through primary hydrolysis by adding process sludge or process sludge and a first basic solution to the filtrate separated in step (S10)

Step (S20) may be a first hydrolysis step of performing selective hydrolysis by adding process sludge or process sludge and a first basic solution to the filtrate separated in step (S10). Preferably, step (S20) may be a step of adding process sludge and the first basic solution to the filtrate separated in step (S10).

The process sludge includes a first cake to be described later, and lithium, nickel, cobalt, and manganese that have not yet been separated from the first cake separated in step (S30) to be described later are left as fine powder. can Preferably, the process sludge may be a first cake. The first basic solution may include a sodium carbonate (Na ₂ CO ₃ ) aqueous solution.

The sodium carbonate aqueous solution may have a sodium carbonate content of 10 to 25% by weight based on the total weight of the sodium carbonate aqueous solution. During the hydrolysis reaction, the reaction temperature may be 45 to 90 °C, the reaction time may be 10 to 60 minutes, and stirring may be performed at a speed of 300 to 600 rpm.

The filtrate may contain aluminum, iron, magnesium, etc. used in the construction of the electrode material of the secondary battery as metal impurities, and the metal impurities may be separated and removed by selective hydrolysis in the form of hydroxide.

In addition, the primary hydrolysis may include the following reaction.

① MeCl ₂ + Na ₂ CO ₃ → MeCO ₃ (s) + 2NaCl [Me: metal impurities such as Al and Fe]

② 2LiCl + Na ₂ CO ₃ → Li ₂ CO ₃ (l) + 2NaCl [Valuable metals such as Li, Ni, Co, and Mn do not precipitate and exist in solution.]

Step (S20) may further include a filtration process for removing precipitates after the first hydrolysis reaction, and metal impurities precipitated according to the first hydrolysis reaction may be removed through filtration.

The hydrolysis and filtrate using the first basic solution may have a pH in the range of 4.0 to 4.8, and if the pH is out of the range, the loss rate of the valuable metal and the removal rate of metal impurities may vary. The filtrate hydrolyzed and filtered using the first basic solution may preferably have a pH in the range of 4.5 to 4.8.

In this embodiment, according to the step (S40) to be described later, the first cake separated in the step (S30) may be added during the step (S20). The first cake may be one in which nickel, cobalt, and manganese are separated in the form of a precipitate cake, and may be a sludge cake that has not undergone a filtration process such as a filter press.

The first cake may act as a pH adjusting agent for the first hydrolysis reaction. By adding the first cake to the filtrate separated in step (S10), the pH may be adjusted to the range of 2.5 to 3.5, preferably to the range of 3.0 to 3.5. Subsequently, the pH of the filtrate may be adjusted to a range of 4.0 to 4.8, preferably 4.5 to 4.8, by adding the first basic solution. By adding and reusing the first cake to the filtrate after acid leaching, the input amount of the first basic solution can be reduced and the loss rate of nickel, cobalt, and manganese can be reduced.

Step (S30): Separating lithium through secondary hydrolysis by adding a second basic solution to the filtrate separated in step (S20), obtaining a first cake, and separating the supernatant

Step (S30) may be a second hydrolysis step of performing continuous hydrolysis by adding a second basic solution to the filtrate separated in step (S20). The second basic solution may include an aqueous sodium carbonate solution, and the sodium carbonate aqueous solution may have a sodium carbonate content of 10 to 25% by weight based on the total weight of the sodium carbonate aqueous solution.

For example, the secondary hydrolysis may include the following reaction.

① MeCl ₂ + Na ₂ CO ₃ → MeCO ₃ (s) + 2NaCl [Me: Valuable metals such as Ni, Co, and Mn]

② 2LiCl + Na ₂ CO ₃ → Li ₂ CO ₃ (l) + 2NaCl [Li exists as a solution without precipitating]

In addition to valuable metals such as nickel, cobalt, and manganese, calcium (Ca), magnesium (Mg), and iron (Fe) added to waste electrode materials for the purpose of improving battery characteristics or introduced in the process of separating and recovering waste electrode materials , aluminum (Al), silicon (Si), and other metal impurities may exist.

Although many of the metal impurities can be removed through the primary hydrolysis in step (S20), it is difficult to completely remove some calcium (Ca), magnesium (Mg), and silicon (Si). In addition, calcium, magnesium, and sodium contained in the sodium carbonate introduced in the second hydrolysis step must also be excluded from the complex sulfate solution below the required value (spec). To this end, while stirring the filtrate at 250 to 350 rpm in inducing the hydrolysis reaction, sodium carbonate is added to the filtrate at a temperature above room temperature, preferably 45 to 75 ° C., so that sodium carbonate is lithium, nickel, cobalt, manganese reacts quantitatively with the metal components to precipitate and separate as carbonates.

In step (S30), lithium is separated into a solution after the secondary hydrolysis reaction, and the first cake in which nickel, cobalt, and manganese are precipitated and the supernatant in which nickel, cobalt, and manganese remain as fine powder can be separated and obtained. . Although not shown, in step (S30), any one or more of pickling and washing processes may be further performed after the secondary hydrolysis reaction, and the first cake is removed after the pickling liquid or the washing liquid is removed. It may contain process sludge that settles on

The first cake may be reused for the primary hydrolysis reaction of the step (S20) according to the step (S40), and the supernatant may be subjected to a filter press process according to the step (S50) to be described later.

Step (S40): Adding the first cake separated in step (S30) to the filtrate in step (S20)

Step (S40) is to use the process sludge generated in step (S30) for the primary hydrolysis in step (S20), adding the first cake to the filtrate separated in step (S10) can be

In this case, in the (S20) step, the filtrate separated in the (S10) step and the first cake may be mixed to adjust the pH of the filtrate to the range of 2.5 to 3.5, preferably to the range of 3.0 to 3.5. can Subsequently, the pH of the filtrate may be adjusted to a range of 4.0 to 4.8, preferably, to a range of 4.5 to 4.8 by adding the first basic solution.

When the first cake and the first basic solution are added, the filtrate may induce a first hydrolysis reaction while stirring at 300 to 600 rpm at a temperature of 45 to 90 °C.

Step (S50): Obtaining a second cake containing nickel, cobalt, and manganese present in the supernatant by performing a filter press process on the supernatant separated in step (S30).

Step (S50) may be a step of recovering nickel, cobalt, and manganese remaining as fine powder in the supernatant after the secondary hydrolysis in step (S30) through additional filtration.

The supernatant may have a pH in the range of 7 to 8, and a precipitate containing nickel, cobalt, and manganese may be formed as the pH of the supernatant is adjusted to 9 to 10 by adding a heavy metal treatment agent such as aqueous sodium sulfide solution. . The precipitate may be filtered through a filter press to obtain a second cake.

Step (S60): Leaching the second cake separated in step (S50) with a second acidic solution and filtering it

Step (S60) may be a secondary acid leach step in which the second cake obtained in step (S50) is put into a reaction tank containing a second acid solution to obtain an acid leachate, and the acid leachate is filtered to separate the filtrate. there is. The second acidic solution may be a sulfuric acid (H ₂ SO ₄ ) solution.

The second acidic solution may further include a reducing agent to increase acid leaching efficiency of the waste electrode material, and the reducing agent may include hydrogen peroxide (H ₂ O ₂ ), hydrogen sulfide (H ₂ S), and sulfur dioxide (SO ₂ ). It may be one or more selected from the group consisting of, preferably hydrogen peroxide.

Leaching using the second acidic solution may be performed at 50 to 85° C. for 300 to 500 minutes, and may be repeated two or more times if necessary.

The filtrate separated by filtering the acid leachate may be a reaction product, a complex acid salt solution, or may be a nickel-cobalt-manganese complex sulfate solution.

Although not shown, after the step (S60), additional filtration or a tuning step for adjusting the concentration of the resultant complex acid salt solution may be further included.

The nickel, cobalt, and manganese composite sulfate solution prepared by the method according to the present embodiment may have a total loss rate of less than 3% of nickel, nickel, and manganese based on the input amount of waste electrode material of a lithium ion secondary battery as a raw material.

Another embodiment of the present invention relates to a precursor for a lithium ion secondary battery electrode material prepared using the composite sulfate solution prepared by the method according to the previous embodiment and a method for manufacturing a lithium ion secondary battery using the precursor.

Since the precursor for a lithium ion secondary battery electrode material can be prepared by a commonly used method using the complex sulfate solution containing nickel, cobalt, and manganese prepared by the method according to the previous embodiment, a detailed description thereof is omitted. do.

A method for manufacturing a lithium ion secondary battery includes preparing a composite sulfate solution containing nickel, cobalt, and manganese by the method according to the previous embodiment, preparing a precursor for an electrode material using the composite sulfate solution, and the electrode A step of manufacturing a lithium ion secondary battery using a recycled precursor may be included.

Hereinafter, embodiments of the present invention will be described in more detail through specific experimental examples. The following experimental examples are intended to illustrate the present invention, but the present invention is not limited by the following experimental examples.

Experimental Example 1. Process improvement according to the use of the first cake (process sludge) during the first hydrolysis

Acid leaching and primary hydrolysis were performed using the waste electrode material of the lithium ion secondary battery. After acid leaching the waste electrode material with hydrochloric acid, 500 g of a filtrate was obtained by filtering, and the pH of the filtrate was adjusted to about 1.0.

In Preparation Example 1, the first and second hydrolysis is performed by adding a 15% sodium carbonate solution to the filtrate according to an embodiment of the present invention, and the first cake, which is the process sludge, is recovered and the pH is adjusted to about 1.0. The filtrate was added again to adjust the pH of the filtrate to about 3.5. Thereafter, the pH of the final filtrate was adjusted to about 4.8 by adding 15% sodium carbonate solution, and stirred at 85° C. for 30 minutes at a rate of 500 rpm to induce a first hydrolysis reaction.

In Comparative Example 1, a 15% sodium carbonate solution was added to the filtrate adjusted to pH about 1.0 to adjust the pH of the final filtrate to about 4.8, followed by primary hydration under the same temperature, time, and stirring speed conditions as in Preparation Example 1. A degradation reaction was induced.

The conditions of Preparation Example 1 and Comparative Example 1 and the weight (unit: g) of the filtrate and dried residue according to the first hydrolysis reaction are shown in Table 1 below.

division leachate process
sludge
input 15% sodium carbonate solution input amount Primary hydrolysis filtrate Primary hydrolysis dried residue Comparative Example 1 500 - 32.0 461.8 8.62 Preparation Example 1 17.2 12.2 442.9 8.45

Referring to Table 1, Preparation Example 1, in which primary hydrolysis was performed by introducing process sludge, was found to reduce the input amount of 15% sodium carbonate solution by about 61.8% compared to Comparative Example 1.

The content of elements (unit: mg/kg) contained in the leachate, process sludge, and filtrate and residue according to the primary hydrolysis used in Preparation Example 1 and Comparative Example 1 was analyzed and shown in Table 2 below.

division leachate process
sludge Primary hydrolysis filtrate Residue of primary hydrolysis Comparative Example 1 Preparation Example 1 Preparation Example 1 Comparative Example 1 Preparation Example 1 Comparative Example 1 Preparation Example 1 Li 7,490 7,169 308 6,268 7,657 14,760 13,320 Ni 43,190 43,050 58,490 39,100 41,410 235,700 235,100 Co 9,441 9,455 17,330 8,671 9,414 41,250 40,080 Mn 8,027 8,150 14,580 7,715 8,234 17,810 18,050 Mg 47 52 4 12 16 137 141 Ca 115 126 8 6 8 338 354 Zn 0 0 0 0 0 0 0 Cu 0 0 0 0 0 18 22 Fe 0 0 0 0 0 269 281 Na 93 94 1,672 3,697 1,910 8,046 2,953 Al 768 782 0 3 0 40,460 40,860 Cr 0 0 0 0 0 19 17 Si 0 0 4 0 0 0 0

Weights (unit: g) of nickel, cobalt, and manganese as valuable metals contained in the leachate, process sludge, and residues from primary hydrolysis used in Preparation Example 1 and Comparative Example 1, and the primary hydrolysis residue As a standard, the loss rates of nickel, cobalt, and manganese (NCM loss rate, unit: %) were calculated and shown in Table 3 below.

division leachate process
sludge Residue of primary hydrolysis NCM loss rate Comparative Example 1 Preparation Example 1 Preparation Example 1 Comparative Example 1 Preparation Example 1 Comparative Example 1 Preparation Example 1 Ni 21.60 22.53 1.01 2.03 1.99 9.41 8.82 Co 4.72 5.03 0.30 0.36 0.34 7.53 6.74 Mn 4.01 4.33 0.25 0.15 0.15 3.82 3.53 Sum 30.33 31.88 1.55 2.54 2.48 8.38 7.77

Referring to Table 3, Preparation Example 1 in which primary hydrolysis was performed by adding process sludge and sodium carbonate solution had a loss rate of nickel, cobalt, and manganese of about 0.61 compared to Comparative Example 1 in which primary hydrolysis was performed by adding only sodium carbonate solution. % was found to decrease.

Experimental Example 2. Process improvement according to pH adjustment by inputting the first cake (process sludge) during the first hydrolysis

In the same manner as in Experimental Example 1, 500 g of a filtrate having a pH of about 1.0 was obtained.

As a production example, according to an embodiment of the present invention, the first and second hydrolysis is performed by adding a 15% sodium carbonate solution to the filtrate, and the first cake, which is the process sludge, is recovered and the pH is adjusted to about 1.0. The filtrate was added again. At this time, the pH of the filtrate was adjusted to 2.5 (Preparation Example 2-1), 3.0 (Preparation Example 2-2) and 3.5 (Preparation Example 3-5) by adjusting the input amount of the process sludge, 15% sodium carbonate solution After adjusting the pH of the final filtrate to about 4.8 by adding, a primary hydrolysis reaction was induced under the same temperature, time and stirring speed conditions as in Preparation Example 1.

The weights (unit: g) of the filtrate and dried residue according to the conditions of Preparation Example 2 and the first hydrolysis reaction are shown in Table 4 below.

division leachate process
sludge
input 15% sodium carbonate solution input amount Primary hydrolysis filtrate Primary hydrolysis dried residue Preparation Example 2-1
(pH 2.5) 500 6.1 13.0 472.1 5.43 Preparation Example 2-2
(pH 3.0) 8.3 8.8 455.1 5.55 Preparation Example 2-3 (pH 3.5) 10.3 5.7 468.3 5.34

The content of elements (unit: mg/kg) contained in the leachate, process sludge, and filtrate and residue according to the primary hydrolysis used in Preparation Examples 2-1 to 2-3 was analyzed and shown in Table 5 below. .

division leachate process
sludge Primary hydrolysis filtrate Residue of primary hydrolysis manufacturing example
2-1 Preparation Example 2-2 Preparation Example 2-3 manufacturing example
2-1 Preparation Example 2-2 Preparation Example 2-3 manufacturing example
2-1 Preparation Example 2-2 Preparation Example 2-3 Li 6,659 6,587 6,580 308 6,288 6,545 6,455 13,030 14,930 14,530 Ni 39,490 40,310 39,720 58,490 39,790 41,840 41,000 228,700 218,300 202,600 Co 9,726 9,893 9,709 17,330 9,853 10,360 10,190 44,170 45,850 39,440 Mn 9,009 9,176 8,985 14,580 9,295 9,753 9,546 24,350 28,160 25,940 Mg 46 44 42 4 12 12 12 205 226 228 Ca 115 100 96 8 5 5 5 516 563 566 Zn 0 0 0 0 0 0 0 0 0 0 Cu 0 0 0 0 0 0 0 13 12 13 Fe 0 0 0 0 0 0 0 306 224 259 Na 318 310 308 1,672 1,843 1,432 845 3,647 3,149 2,199 Al 235 239 243 0 0 0 0 29,310 27,180 31,090 Cr 0 0 0 0 0 0 0 37 37 38 Si 12 11 11 4 4 4 4 769 754 750

Based on the weight (unit: g) of nickel, cobalt, and manganese as valuable metals contained in the leachate used in Preparation Examples 2-1 to 2-3 and the residue from the primary hydrolysis, and the residue from the primary hydrolysis The loss rates of nickel, cobalt, and manganese (NCM loss rate, unit: %) were calculated and shown in Table 6 below.

division leachate Residue of primary hydrolysis NCM loss rate manufacturing example
2-1 manufacturing example
2-2 manufacturing example
2-3 manufacturing example
2-1 manufacturing example
2-2 manufacturing example
2-3 manufacturing example
2-1 manufacturing example
2-2 manufacturing example
2-3 Ni 20.10 20.64 20.46 1.24 1.21 1.08 6.18 5.87 5.29 Co 4.97 5.09 5.03 0.24 0.25 0.21 4.83 5.00 4.18 Mn 4.59 4.71 4.64 0.13 0.16 0.14 2.88 3.32 2.98 Sum 29.66 30.44 30.14 1.61 1.62 1.43 5.44 5.33 4.75

Referring to Tables 4 and 6, it was found that as the pH of the filtrate was increased through the input of the process sludge, the input amount of the sodium carbonate solution was reduced, and the loss rate of nickel, cobalt, and manganese was reduced.

Experimental Example 3. Process improvement according to pH adjustment of acid leachate during primary hydrolysis

As a manufacturing example, acid leaching and primary hydrolysis were performed using the waste electrode material of a lithium ion secondary battery according to an embodiment of the present invention.

At this time, the pH of the filtrate after acid leaching was adjusted to 0.5 (Preparation Example 3-1) and 1.0 (Preparation Example 3-2) by adjusting the input conditions of hydrochloric acid. Thereafter, the pH was adjusted to 3.5 by adding process sludge to the filtrate according to each preparation example, and the pH of the final filtrate was adjusted to about 4.8 by adding 15% sodium carbonate solution, followed by the same temperature and time as in Preparation Example 1 And the primary hydrolysis reaction was induced under the stirring speed condition.

The weights (unit: g) of the filtrate and the dried residue according to the conditions of Preparation Example 3 and the first hydrolysis reaction are shown in Table 7 below.

division leachate process
sludge
input 15% sodium carbonate solution input amount Primary hydrolysis filtrate Primary hydrolysis dried residue Preparation Example 3-1
(pH 0.5) 500 18.7 4.9 470.9 4.07 Preparation Example 3-2
(pH 1.0) 12.3 7.7 456.6 4.77

The content of elements (unit: mg/kg) contained in the leachate, process sludge, and filtrate and residue according to the primary hydrolysis used in Preparation Examples 3-1 and 3-2 was analyzed and shown in Table 8 below. .

division leachate process
sludge Primary hydrolysis filtrate Residue of primary hydrolysis Preparation Example 3-1 Preparation Example 3-2 Preparation Example 3-1 Preparation Example 3-2 Preparation Example 3-1 Preparation Example 3-2 Li 6,746 6,758 308 6,729 6,917 15,410 12,610 Ni 45,750 46,160 58,490 47,370 47,080 312,400 312,700 Co 8,248 8,246 17,330 9,041 8,841 41,950 43,360 Mn 8,176 8,185 14,580 8,901 8,866 29,630 25,980 Mg 2 2 4 2 2 87 99 Ca 4 4 8 2 2 194 246 Zn 0 0 0 0 0 0 0 Cu 0 0 0 0 0 36 21 Fe 0 0 0 0 0 720 502 Na 280 284 1,672 1,010 1,393 2,054 2,245 Al 356 357 0 0 0 63,860 46,780 Cr 0 0 0 0 0 150 108 Si 9 9 4 5 5 949 757

The weight (unit: g) of nickel, cobalt, and manganese as valuable metals contained in the leachate, process sludge, and residue from the first hydrolysis used in Preparation Examples 3-1 and 3-2, and the first hydrolysis The loss rates of nickel, cobalt, and manganese (NCM loss rate, unit: %) based on the residue were calculated and shown in Table 9 below.

division leachate process sludge Residue of primary hydrolysis NCM loss rate Preparation Example 3-1 Preparation Example 3-2 Preparation Example 3-1 Preparation Example 3-2 Preparation Example 3-1 Preparation Example 3-2 Preparation Example 3-1 Preparation Example 3-2 Ni 23.97 23.80 1.09 0.72 1.27 1.49 5.30 6.27 Co 4.45 4.34 0.32 0.21 0.17 0.21 3.84 4.77 Mn 4.36 4.27 0.27 0.18 0.12 0.12 2.76 2.90 Sum 32.78 32.41 1.69 1.11 1.56 1.82 4.77 5.63

Referring to Table 9, Preparation Example 3-1 in which the pH was adjusted to 0.5 after hydrochloric acid leaching and filtration showed a loss rate of about nickel, cobalt, and manganese compared to Preparation Example 3-2 in which the pH was adjusted to 1.0 during the first hydrolysis. It was found to decrease by 0.86%.

Experimental Example 4. Pilot test for production process application

Based on the lab scale results of Experimental Examples 1 to 3, a pilot scale process was performed according to an embodiment of the present invention.

In Preparation Example 4, acid leaching and primary hydrolysis were performed using the waste electrode material of the lithium ion secondary battery. At this time, the pH of the filtrate was adjusted to 0.5 after acid leaching by adjusting conditions for adding hydrochloric acid. Thereafter, the pH was adjusted to 3.5 by adding process sludge to the filtrate, and the pH of the final filtrate was adjusted to about 4.8 by adding 15% sodium carbonate solution, and then under the same temperature, time and stirring speed conditions as in Preparation Example 1. A first hydrolysis reaction was induced.

In Comparative Example 2, a primary hydrolysis reaction was induced under the same conditions of temperature, time, and stirring speed as in Preparation Example 1, without adding process sludge to the filtrate after acid leaching.

The processes according to Preparation Example 4 and Comparative Example 2 were repeated 5 times, respectively, and the input amount of the process sludge and 15% sodium carbonate solution (unit: L) and the waste electrode material raw material, process sludge, raw material and process sludge Nickel, cobalt and manganese according to the total weight of nickel, cobalt, and manganese (NCM metal amount, unit: kg) as valuable metals included in the mixture and the residue from the primary hydrolysis, and the concentration of the primary hydrolysis residue compared to the input raw material The manganese loss rate (unit: %) was calculated and shown in Table 10 below.

division process
sludge 15% sodium carbonate
solution Raw material process
sludge raw material+
process
sludge Primary
hydrolysis
residue loss rate input NCM metal amount Production Example 4 1 time 1,129 230 674.8 118.1 792.8 21.4 2.70 Episode 2 460 100 731.9 45.0 776.8 25.9 3.34 3rd time 685 100 720.6 73.5 794.1 27.0 3.40 4 times 687 100 711.4 73.1 784.5 17.9 2.28 5 times 588 90 711.4 60.3 771.7 16.9 2.20 average 710 124 710.0 74.0 784.0 21.8 2.78 Comparative Example 2 1 time - 500 720.5 - 720.5 30.0 4.16 Episode 2 - 500 750.7 - 750.7 71.2 9.49 3rd time - 480 727.9 - 727.9 40.5 5.57 4 times - 350 717.5 - 717.5 23.6 3.28 5 times - 480 734.7 - 734.7 23.9 3.25 average - 462 730.3 - 759.6 37.8 5.15

Referring to Table 10, in the process according to Preparation Example 4 in which process sludge is re-injected, it was found that the amount of 15% sodium carbonate solution input was reduced by about 73% compared to Comparative Example 2 corresponding to the conventional process.

At the same time, in Production Example 4, the loss rate, which is the amount of nickel, cobalt, and manganese contained in the primary hydrolysis residue, relative to the amount of nickel, cobalt, and manganese contained in the waste electrode material as a raw material and the process sludge re-injected, was 5 times showed an average of less than 3%. Preparation Example 4 was found to reduce the loss rate of nickel, cobalt and manganese by about 2.38% compared to Comparative Example 2.

Claims (12)

(S10) leaching and filtering the waste electrode material of the lithium ion secondary battery with a first acidic solution;
(S20) adding process sludge or process sludge and a first basic solution to the filtrate separated in step (S10) to perform primary hydrolysis to separate metallic impurities;
(S30) adding a second basic solution to the filtrate separated in step (S20) to perform secondary hydrolysis to separate lithium, obtain a first cake, and separate the supernatant;
(S40) adding the first cake separated in step (S30) to the filtrate in step (S20);
(S50) A filter press (F/P) process is performed on the supernatant separated in step (S30) to remove nickel (Ni), cobalt (Co), and manganese (Mn) present in the supernatant. Obtaining 2 cakes; and
(S60) leaching the second cake separated in step (S50) with a second acidic solution and filtering;
The method of producing a composite sulfate solution from waste electrode material of a lithium ion secondary battery, wherein the process sludge includes the first cake. According to claim 1,
The first acidic solution includes hydrochloric acid, nitric acid or sulfuric acid,
The method of preparing a complex sulfate solution from the waste electrode material of a lithium ion secondary battery in which the filtrate separated in step (S10) has a pH in the range of 0.5 to 1.0. According to claim 1,
Wherein the first acidic solution further comprises at least one reducing agent selected from the group consisting of hydrogen peroxide, hydrogen sulfide and sulfur dioxide. According to claim 1,
The metal impurities are a method for producing a composite sulfate solution from a waste electrode material of a lithium ion secondary battery containing iron (Fe), aluminum (Al) and copper (Cu). According to claim 1,
The first basic solution and the second basic solution include an aqueous solution of sodium carbonate,
The sodium carbonate aqueous solution has a sodium carbonate content of 10 to 25% by weight based on the total weight of the sodium carbonate aqueous solution, a method for producing a composite sulfate solution from waste electrode material of a lithium ion secondary battery. According to claim 5,
The step (S40) adds the first cake to the filtrate separated in the step (S10),
The step (S20) is to add the first basic solution to the filtrate to which the first cake is added, a method for preparing a composite sulfate solution from waste electrode material of a lithium ion secondary battery. According to claim 6,
In the step (S40), the first cake is added to the filtrate separated in the step (S10) to adjust the filtrate to a pH in the range of 2.0 to 3.5. A method for preparing a sulfate solution. According to claim 5,
In the step (S20), the first basic solution is added to the filtrate to which the first cake is added to adjust the filtrate to a pH in the range of 4.0 to 4.8. A method for preparing a sulfate solution. According to claim 1,
The second acidic solution includes a sulfuric acid solution,
The composite sulfate solution is a nickel (Ni) -cobalt (Co) -manganese (Mn) composite sulfate solution, a method for preparing a composite sulfate solution from waste electrode material of a lithium ion secondary battery. According to claim 9,
A method for preparing a composite sulfate solution from waste electrode materials of a lithium ion secondary battery, wherein the total loss rate of nickel, cobalt, and manganese is less than 3% when the composite sulfate solution is prepared. A precursor for a lithium ion secondary battery electrode material prepared using the complex sulfate solution prepared by the method according to any one of claims 1 to 10. Preparing a complex sulfate solution by the method according to any one of claims 1 to 10;
preparing a precursor for an electrode material using the complex sulfate solution; and
Method for manufacturing a lithium ion secondary battery comprising the step of manufacturing a lithium ion secondary battery using the precursor for the electrode material.

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