JP7378058B2 - Separation method for manganese and nickel - Google Patents

Description

The present invention is a separation process in which manganese and nickel, which are constituent metals, are separated from a material containing lithium metal oxide (a composite oxide of lithium and other metals) containing manganese and nickel by hydrothermal organic acid leaching treatment. Regarding the method.

A lithium ion battery (hereinafter also referred to as LiB) is a secondary battery that can be charged and discharged by the movement of lithium ions. LiB is small and lightweight, and has higher energy efficiency than conventional secondary batteries, so it is widely used in mobile phones, personal computers, electronic devices, etc. In recent years, LiB has been adopted by automobile manufacturers around the world as batteries for electric vehicles and hybrid vehicles, and the demand for it is expected to continue to expand (Non-Patent Document 1). LiB uses metals such as aluminum foil and copper foil, as well as rare metals for the positive electrode plate.

Currently, lithium cobalt oxide (LiCoO ₂ ), lithium nickel oxide (LiNiO ₂ ), and lithium manganate (LiMn ₂ O ₄ ) are known as types of positive electrode materials. Furthermore, a ternary positive electrode material that is a mixture of cobalt, nickel, and manganese is also known. In this way, rare metals such as cobalt, nickel, and manganese are used in LiB, and as the demand for LiB increases, the demand for rare metals also increases, and there is a strong need to secure rare metal resources. However, rare metal resources are unevenly produced in different regions and are influenced by the policies and political situations of major producing countries, easily causing supply disruptions. Furthermore, environmental pollution due to discarded used LiB (hereinafter also referred to as waste lithium battery or waste LiB) has become a problem. In addition to this increasing demand, there is an urgent need to develop recycling technology for waste LiB due to problems such as difficulty in securing resources and environmental pollution.

There are two main methods for refining metals: pyrometallurgy and hydrometallurgy. In the current LiB separation and recovery process, a hydrometallurgical method is mainly used. Hydrometallurgy is a method of refining metals in a solvent. After metal ions are leached from metal-containing waste using a solvent, they are recovered by precipitation and separation. Conventionally, in a system with H ₂ O ₂ added as a reducing agent, about 1 to 2 M of sulfuric acid (Non-patent Document 2), nitric acid (Non-Patent Document 3), or citric acid (Non-patent Document 4) was operated at 70 to 90°C. , acid leaching methods for recovering metal ions have been studied at the practical and research level. As an acid leaching reaction for a ternary system, a leaching reaction of LiNi _1/3 Co _1/3 Mn _1/3 O ₂ was carried out by adding H ₂ O ₂ to 1M sulfuric acid at a reaction temperature of 40°C. (Non-patent document 5). In the leaching reaction disclosed in Non-Patent Document 5, the leaching rate of all metal ions increased as the reaction time increased, and leaching was completed in 60 minutes. Of these, the leaching rate of lithium (Li) is the highest, and this is because among the M-O bonds (M: lithium (Li), cobalt (Co), nickel (Ni), or manganese (Mn)), the Li-O bond is This is due to the fact that it is easily dissociated under acidic conditions.

Weiguang et al., A critical review and analysis on the recycling of spent lithium-ion batteries, ACS Sustainable Chem Eng, 6, 1504 (2018) M. K. Jha et al., Recovery of lithium and cobalt from waste lithium ion batteries of mobile phone, Waste Management, 33, 1890, (2013) C. K. Lee et al., Preparation of LiCoO2 from spent lithium-ion batteries. Journal of Power Sources, Jornal of Power Source, 109, 17, (2002) Rabeeh G et al., Conservation & Recycling, 136, 418 (2018) Li He et al., Recovery of Lithium, Nickel, Cobalt, and Manganese from Spent Lithium-ion Batteries Using l-Tartaric Acid as a Leachant, ACS Sustainable Chem Eng, 5, 714 (2017) Li L et al., Recovery of metals from spent lithium-ion batteries with organic acids as leaching reagents and environmental assessment, Journal of Power Sources, 233, 180 (2013)

However, when sulfuric acid or nitric acid is used as in the past, toxic gases such as SOx and NOx are generated, which places a large burden on the environment, and H ₂ O ₂ added as a reducing agent is also explosive and carcinogenic. There are safety issues, such as having a There is also a report (Non-Patent Document 6) that the recovery rate of metal ions decreases in a system without the addition of H ₂ O ₂ , and there is a need for improvement in the acid leaching method.

On the other hand, in the past, LiB positive electrode materials containing lithium, cobalt, nickel, manganese, etc. were acid leached using a method such as sulfuric acid + hydrogen peroxide, and the leached water-soluble ions of lithium, cobalt, nickel, and manganese were extracted with PC88A (monocarbon). A method of isolation by liquid-liquid extraction with a solvent such as -2-ethylhexyl-(2-ethylhexyl)phosphate) has also been used. However, PC88A had problems such as being expensive and requiring a long time for the separation process.

Therefore, the present invention was made in view of the above problems, and is a method for separating manganese and nickel from a material containing lithium metal oxide containing manganese and nickel in a safer and lower cost manner than before. The purpose of the present invention is to provide a method for separating manganese and nickel.

The present invention provides a separation method for separating manganese and nickel from a material containing a lithium metal oxide containing manganese and nickel, the method comprising: using an aqueous solution of a complex-forming organic acid; The leaching step includes: (a) setting the temperature of the aqueous solution to 65° C. or higher and 85° C. or lower, and leaching the manganese from the material into the aqueous solution; and (b) ) A step of increasing the temperature of the aqueous solution to more than 85° C. and not more than 110° C., and leaching the nickel into the aqueous solution from the solid obtained by liquid phase separation of the aqueous solution after the step (a). and a method for separating nickel.

According to the present invention, since sulfuric acid and nitric acid, which may generate toxic gases, and expensive PC88A are not used, manganese and nickel can be separated from materials more safely and at lower cost than before. Can be done.

FIG. 1A is a schematic diagram showing a conventional separation and recycling flow of constituent metals of LiB, and FIG. 1B is a schematic diagram showing a separation and recycling flow of constituent metals of LiB using the present invention. _{Cobalt , nickel} and 1 is a graph showing the leaching rate (wt %) of manganese, where the leaching rate (wt %) shows the weight % of the leached metal with respect to the weight of each metal contained in the material. _{Cobalt , nickel} and 1 is a graph showing the leaching rate (wt %) of manganese, where the leaching rate (wt %) shows the weight % of the leached metal with respect to the weight of each metal contained in the material. Leaching of lithium, cobalt and nickel when acid leaching a commercially available material containing 0.1 g each of LiCoO ₂ and LiNiO ₂ with 5 g of 0.4 mol/L citric acid aqueous solution at 90°C. Figure 2 is a graph showing the leaching rate (wt %), which shows the weight % of metal leached relative to the weight of each metal contained in the material. Leaching of lithium, cobalt, and nickel when a commercially available material containing 0.1 g of each of LiCoO ₂ and LiNiO ₂ was acid leached at 100°C using 5 g of a 0.4 mol/L citric acid aqueous solution. 1 is a graph showing the leaching rate (wt %), which shows the weight % of the weight of metal leached relative to the weight of each metal contained in the material. Commercially available LiCoO ₂ -1 (manufactured by STREM CHEMICAL Co., Ltd. Lot. A4080019), commercially available LiCoO ₂ -2 (manufactured by STREM CHEMICAL Co., Ltd. Lot. 27596800), and crushed products of calcined waste LiB materials, and cobalt leaching rate (wt%) ) is a graph showing the relationship between FIG. 7A is a graph showing the particle size distribution of commercially available LiCoO ₂ -1, FIG. 7B is a graph showing the particle size distribution of commercially available LiCoO ₂ -2, and FIG. 7C is a graph showing the particle size distribution of commercially available LiCoO 2 -2. It is a graph showing the particle size distribution of the pulverized material.

<Outline of the present invention>
The present inventors prepared a lithium metal oxide containing, for example, cobalt, nickel, and/or manganese, which is often used as a positive electrode material, in order to establish a recycling process for waste LiB, and Hydrothermal organic acid leaching treatment was performed using an aqueous solution of a complex-forming organic acid. Here, hydrothermal organic acid leaching treatment is a type of hydrometallurgy process in which leaching is carried out in liquid water using an organic acid as a leaching agent and keeping the reaction temperature above the boiling point of water in order to avoid using an additional reducing agent. It is one.

As a result, it was found that the leaching rate of cobalt, nickel, and manganese from lithium metal oxide differs depending on the temperature. By changing the temperature of the complex-forming organic acid aqueous solution in stages during hydrothermal organic acid leaching treatment, cobalt, nickel, and manganese can be separated from metal oxides in a high yield. I found out that it can be recovered. The present invention is based on this knowledge.

<Embodiment>
The method for separating nickel and manganese according to the embodiment of the present invention is used, for example, to separate and recover predetermined metals in the recycling process of waste LiB. Generally, LiB uses lithium oxides such as LiCoO ₂ , LiNiO ₂ , LiMnO ₂ , and ternary positive electrode materials as positive electrode materials. Therefore, there is a high possibility that the waste LiB contains cobalt, nickel, and manganese, and it is highly necessary to separate and recover them for recycling. In this embodiment, a method for separating nickel and manganese will be explained using an example in which the method is used for recycling waste LiB containing cobalt, nickel, and manganese.

In the recycling process of separating and recovering lithium, cobalt, nickel, and manganese from waste LiB, especially the cathode material of waste LiB, as shown in Figure 1B, waste LiB is first discharged (e.g., placed in an acidic aqueous solution in a battery) without being calcined. discharge). As shown in FIG. 1A, in the conventional recycling process of waste LiB, waste LiB is incinerated (calcining process) and discharged, but unlike the conventional process, the present embodiment is characterized in that no calcination process is performed. . This is because the calcination treatment increases the particle size of the lithium metal oxide in the waste LiB, and even if it is subsequently crushed, the particle size may vary, which may slow down the leaching rate of the metal.

Next, after decomposing the waste LiB, the decomposed waste LiB is dispersed in alkaline water or an organic solution and separated by specific gravity to form an upper layer made of organic matter, a dispersed layer in which lithium metal oxide is dispersed, and a metal as a precipitated layer. Separate from foil. In this embodiment, lithium, cobalt, nickel, and manganese are separated and recovered from the lithium metal oxide in the gravity-separated dispersion layer by hydrothermal organic acid leaching treatment. In the hydrothermal organic acid leaching treatment, metal ions to be separated and recovered from the lithium metal oxide are leached into an aqueous solution of a complex-forming organic acid (hereinafter referred to as an organic acid aqueous solution) to be described later, and the metal is separated and recovered. At this time, since the temperature at which metal ions are leached into the organic acid aqueous solution differs depending on the type of metal, a predetermined metal can be separated and recovered.

Specifically, an organic acid aqueous solution is prepared, and the lithium metal oxide taken out from the dispersion layer is added to the organic acid aqueous solution and mixed. Next, the organic acid aqueous solution containing the lithium metal oxide is heated to a predetermined temperature to leach out the metal ions. The organic acid aqueous solution from which the metal ions have been leached is subjected to liquid phase separation, and the leached metal ions are recovered from the liquid phase (organic acid aqueous solution). Then, the solid obtained by liquid phase separation is poured into an organic acid aqueous solution, and the above operation is repeated. At this time, other metals can be similarly separated and recovered by increasing the leaching temperature of the metal ions each time the above operation is repeated.

In the case of cobalt, nickel, and manganese, the leaching temperature of metal ions into the organic acid aqueous solution increases in the order of manganese, nickel, and cobalt. Therefore, in this embodiment, manganese, nickel, and cobalt are separated and recovered in this order. Specifically, first, the temperature of a citric acid aqueous solution as an organic acid aqueous solution mixed with the lithium metal oxide obtained as described above is set to 65°C or more and 85°C or less, and manganese is extracted from the lithium metal oxide with citric acid. It is leached into an aqueous solution (step (a)).

Lithium and manganese are leached into the liquid phase (citric acid aqueous solution) by the hydrothermal organic acid leaching treatment. Lithium and manganese can be recovered by treating them as solutions in a conventional manner and finally precipitating them as their respective insoluble salts, such as carbonates, by changing the precipitation conditions. Note that if it is clear that the lithium metal oxide contains only manganese and nickel, manganese and nickel can be separated by only this step.

Next, the solid obtained by liquid phase separation is mixed with a citric acid aqueous solution, the temperature of the citric acid aqueous solution is set to more than 85°C and 110°C or less, and the organic acid aqueous solution after step (a) is obtained by liquid phase separation. Nickel is leached from the solid into an aqueous citric acid solution (step (b)).

Lithium and nickel are leached into the liquid phase (in the citric acid aqueous solution) by the hydrothermal organic acid leaching treatment. Lithium and nickel can be recovered by treating them as solutions in a conventional manner and finally precipitating them as insoluble salts or complexes by changing the precipitation conditions. On the other hand, cobalt is separated from the solid obtained by liquid phase separation. By separating manganese and nickel in this way, cobalt can also be separated at the same time.

The cobalt-containing solid is appropriately treated to recover the cobalt. Cobalt may be recovered from the solids by a hydrothermal organic acid leaching process. Below, a case will be described in which cobalt is recovered by hydrothermal organic acid leaching treatment. In this case, the solid obtained by liquid phase separation is mixed with an aqueous citric acid solution, the temperature of the aqueous citric acid solution is made to exceed 110 ° C., and the solid obtained by liquid phase separation of the organic acid aqueous solution after step (b), Cobalt is leached into an aqueous citric acid solution (step (c)).

The hydrothermal organic acid leaching process leaches lithium and cobalt into the liquid phase. Lithium and cobalt can be recovered by treating them directly as solutions in a conventional manner and finally precipitating them as their respective insoluble salts or complexes by changing the precipitation conditions. Note that the lithium extracted into the liquid phase in each step of steps (a) to (c) can be recovered as solid Li ₂ Co ₃ , for example.

<About organic acid aqueous solution>
As the complex-forming organic acid contained in the organic acid aqueous solution used in the hydrothermal organic acid leaching treatment of the present invention, those having reducing properties and the ability to form a complex are used. Examples of such organic acids include, in addition to the above-mentioned citric acid, oxalic acid, tartaric acid, lactic acid, succinic acid, malic acid, fumaric acid, maleic acid, and malonic acid. The concentration of the organic acid aqueous solution depends on the type of organic acid used, but is in the range of 0.01 to 5 mol/L, preferably 0.1 to 1 mol/L. If the organic acid concentration is too low, leaching will not take place, and if it is too high, precipitation will occur due to the salting out effect. Further, the solid concentration (S/L) in the organic acid solution is preferably 10 to 100 g/L. Examples of the solvent include water, an aqueous alcohol solution, and especially water or a 10-90% ethanol aqueous solution.

<About hydrothermal organic acid leaching temperature>
The leaching temperatures of lithium, cobalt, nickel, and manganese, that is, the temperature conditions of the hydrothermal organic acid leaching treatment will be explained in more detail.

Hydrothermal organic acid leaching treatment of lithium can substantially leaching lithium at temperatures below 70°C. Lithium is leached even at the following leaching temperatures for manganese, nickel, and cobalt.

The hydrothermal organic acid leaching treatment of manganese is carried out at a temperature of 65°C to 85°C, preferably 70°C to 80°C, especially 70 to 75°C. If the temperature exceeds 85°C, a considerable amount of nickel and cobalt will be leached out along with manganese, making it difficult to efficiently separate manganese. If the temperature is lower than 65°C, manganese will not be sufficiently leached out.

The hydrothermal organic acid leaching treatment of nickel is carried out at temperatures above 85°C to 110°C, preferably from 90°C to 110°C. When the temperature exceeds 110°C, a considerable amount of cobalt is leached out along with nickel, making it difficult to efficiently separate nickel. If the temperature is lower than 85°C, nickel will not be sufficiently leached out.

The hydrothermal organic acid leaching treatment of cobalt is carried out at temperatures above 110°C, preferably between above 110°C and 150°C. If the temperature exceeds 150°C, metals other than cobalt may be leached out, making it difficult to efficiently separate cobalt. If the temperature is lower than 110°C, cobalt will not be sufficiently leached out.

<About the time of hydrothermal organic acid leaching treatment>
The time for hydrothermal organic acid leaching treatment varies depending on the leaching temperature. The leaching time for lithium is 3 minutes to 30 minutes, preferably 5 minutes to 15 minutes, the leaching time for manganese is 3 minutes to 30 minutes, preferably 5 minutes to 15 minutes, and the leaching time for nickel is 3 minutes to 15 minutes. 30 minutes, for example 5 minutes to 10 minutes at a temperature of 90° C. to 110° C., and the cobalt leaching time is 5 minutes to 30 minutes, preferably 5 minutes to 15 minutes. In a preferred embodiment, lithium is heated at a temperature of 60°C to 150°C for 3 minutes to 15 minutes, manganese is heated to a temperature of 70°C to 80°C for 3 minutes to 5 minutes, and nickel is heated at a temperature of 90°C to 110°C for 3 minutes to 15 minutes. Cobalt is preferably subjected to hydrothermal organic acid leaching treatment at a temperature of 120° C. to 150° C. for 10 minutes to 40 minutes.

<Action and effect>
In the above configuration, the method for separating manganese and nickel according to the embodiment of the present invention uses an organic acid aqueous solution (an aqueous solution of a complex-forming organic acid) to The leaching process includes a leaching process in which LiB (material) is subjected to a hydrothermal organic acid leaching process, and the leaching process includes (a) setting the temperature of the organic acid aqueous solution to 65°C or higher and 85°C or lower, and extracting manganese from the waste LiB into the organic acid aqueous solution; nickel is leached into the organic acid aqueous solution from the solid obtained by liquid phase separation of the organic acid aqueous solution after (a) step, (b) the temperature of the organic acid aqueous solution is set to more than 85°C and 110°C or less, and leaching out manganese and nickel from waste LiB containing lithium metal oxide containing manganese and nickel.

Therefore, in the method for separating manganese and nickel according to the embodiment of the present invention, manganese and nickel can be separated by hydrothermal organic acid leaching treatment. Therefore, manganese and nickel can be separated from waste LiB more safely and at lower cost than before.

<Verification experiment>
(Verification experiment 1)
In verification experiment 1, a material in which LiCoO ₂ , LiNiO ₂ and LiMnO ₂ were mixed was prepared, and manganese was separated from the material in which LiCoO ₂ , LiNiO ₂ and LiMnO ₂ were mixed . Specifically, a material prepared by mixing 0.03 g of each of commercially available LiCoO ₂ , LiNiO ₂ and LiMnO ₂ was mixed with 5 g of a 0.4 mol/L citric acid aqueous solution, and heated at 70°C and 80°C. Hydrothermal organic acid leaching treatment was performed for 5 minutes at . Thereafter, the citric acid aqueous solution was rapidly cooled and filtered to remove solids. The filtered citric acid aqueous solution was subjected to mass spectrometry using ICP (Inductively Coupled Plasma) emission spectrometry, and the weight of the metal leached into the citric acid aqueous solution was determined. The results at 70°C are shown in Figure 2, and the results at 80°C are shown in Figure 3. In FIGS. 2 and 3, the horizontal axis represents the type of metal, and the vertical axis represents the leaching rate (weight %), which indicates the weight % of the leached metal relative to the weight of each metal contained in the prepared material.

Looking at Figures 2 and 3, it can be seen that at both 70°C and 80°C, the amount of manganese leached is greater than that of cobalt and nickel. From this result, it was confirmed that manganese could be separated from a material in which LiCoO ₂ , LiNiO ₂ and LiMnO ₂ were mixed . It was confirmed that the leaching rate of manganese was high at both 70°C and 80°C, and that manganese was particularly easy to separate in the temperature range of 70°C to 80°C.

(Verification experiment 2)
In verification experiment 2, a material in which LiCoO ₂ and LiNiO ₂ were mixed was prepared, and nickel was separated from the material in which LiCoO ₂ and LiNiO ₂ were mixed . Specifically, a material prepared by mixing 0.1 g of each of commercially available LiCoO ₂ and LiNiO ₂ was mixed with 5 g of a 0.4 mol/L (M) citric acid aqueous solution, and heated at 90°C and 100°C. Then, hydrothermally induced acid leaching treatment was performed for 5 minutes, 10 minutes, and 30 minutes, respectively. Thereafter, in the same manner as Verification Experiment 1, the weight of the metal leached into the citric acid aqueous solution was determined. Figure 4 shows the results at 90°C, and Figure 5 shows the results at 100°C. The horizontal axis of each figure is the reaction time, and the vertical axis is the leaching rate. The definition of leaching rate is the same as in Figure 2.

Looking at FIGS. 4 and 5 , it can be seen that at both 90 °C and 100 °C, the amount of leaching of nickel was greater than that of cobalt at each reaction time. From this result, it was confirmed that nickel could be separated from a material containing LiCoO ₂ and LiNiO ₂ . This result means that when manganese and nickel are separated from waste LiB containing cobalt, nickel, and manganese, nickel can be separated from lithium metal oxide that mainly contains cobalt and nickel after removing manganese. are doing. It was also confirmed that the leaching rate of nickel was high at both 90°C and 100°C, and that nickel was particularly easy to separate in the temperature range of 90°C to 100°C.

(Verification experiment 3)
In verification experiment 3, cobalt was separated from commercially available LiCoO ₂ and pulverized waste LiB materials subjected to calcination treatment, and the relationship between the presence or absence of calcination treatment and the leaching rate of cobalt was investigated. Specifically, a 0.4 M citric acid aqueous solution mixed with 0.05 g of commercially available LiCoO ₂ -1 (manufactured by STREM CHEMICAL Co., Ltd., Lot. A4080019), and a commercially available LiCoO ₂ -2 (manufactured by STREM CHEMICAL Co., Ltd., Lot. 27596800) 0. A 0.4 M citric acid aqueous solution containing 0.05 g of citric acid and a 2.0 M citric acid aqueous solution containing 0.05 g of pulverized calcined waste LiB material were heated under the conditions shown in Figure 6 for 30 minutes under the conditions shown in Figure 6. Acid leaching treatment was performed. Thereafter, in the same manner as Verification Experiment 1, the weight of the metal leached into the citric acid aqueous solution was determined. In FIG. 6, the horizontal axis represents the type of material, and the vertical axis represents the cobalt leaching rate (wt%). The definition of leaching rate is the same as in Figure 2. Since the reaction time is the same, the leaching rate corresponds to the leaching rate. A pulverized product of the fired waste LiB material was prepared by pulverizing LiB with a hammer mill or the like.

Looking at FIG. 6, it can be seen that the leaching rate of cobalt is slowed down by the calcination treatment. In order to investigate the cause of the slowing of the leaching rate of cobalt due to firing treatment, the particle sizes of commercially available LiCoO ₂ -1, commercially available LiCoO ₂ -2, and crushed pieces of fired waste LiB material were measured using laser diffraction and scattering methods. did. FIG. 7A shows the particle size distribution of commercially available LiCoO ₂ -1, FIG. 7B shows the particle size distribution of commercially available LiCoO ₂ -2, and FIG. 7C shows the particle size distribution of the pulverized product of the fired waste LiB material.

As shown in FIG. 7C, the pulverized waste LiB material subjected to the calcination treatment has particle size peaks at 20 μm, 300 μm, and 1400 μm, and compared with the particle size distribution of commercially available LiCoO ₂ shown in FIGS. 7A and 7B, It can be seen that the size distribution is wide and that there is variation in particle size. Furthermore, from FIGS. 7A and 7B, it can be seen that commercially available LiCoO ₂ -1 has a smaller average particle diameter than commercially available LiCoO ₂ -2.

Examining FIG. 6 again based on this result, it can be seen that the smaller the average particle diameter and the smaller the variation in particle size distribution, the greater the cobalt leaching rate and the faster the leaching rate. From this, it is considered that the particle size of the waste LiB increased when it was pre-treated for calcination, and even after it was pulverized, the particle size remained uneven, and as a result, the leaching rate of cobalt was slowed down.

Claims (4)

A separation method for separating the manganese and the nickel from a material containing a lithium metal oxide containing manganese and nickel, the method comprising:
A leaching step in which the material is subjected to a hydrothermal organic acid leaching treatment using an aqueous solution of citric acid as a complex-forming organic acid,
The leaching step includes:
(a) a step of setting the temperature of the aqueous solution to 65° C. or higher and 85° C. or lower, and leaching the manganese from the material into the aqueous solution;
(b) setting the temperature of the aqueous solution to more than 85° C. and not more than 110° C., and leaching the nickel into the aqueous solution from the solid obtained by liquid phase separation of the aqueous solution after the step (a);
A method for separating manganese and nickel, including: the lithium metal oxide further contains cobalt,
The leaching step includes:
(c) a step of increasing the temperature of the aqueous solution to over 110° C. and leaching the cobalt into the aqueous solution from the solid obtained by liquid phase separation of the aqueous solution after the step (b);
2. The method for separating manganese and nickel according to claim 1. The material is waste lithium ion battery material, and before the leaching step,
comprising the step of dispersing the waste lithium ion battery material in an organic solution and separating it into an upper layer of organic matter and a deposited layer containing metal foils,
The leaching step includes performing the hydrothermal organic acid leaching treatment on the precipitated layer.
The method for separating manganese and nickel according to claim 1 or 2. The time for the step (a) is 3 minutes to 30 minutes, and the time for the step (b) is 3 minutes to 30 minutes.
The method for separating manganese and nickel according to any one of claims 1 to 3.

Images