Valuable metal recovery composition and valuable metal recovery method

Abstract

The present invention provides a valuable metal recovery composition comprising a magnetic material and a non-magnetic material and satisfying equation 1. [Equation 1] 0 < [Mn]B / [Mn]A < 19 (In equation 1, [Mn]A and [Mn]B represent the wt% of Mn in the non-magnetic material and the magnetic material, respectively.)

Description

Composition for recovering valuable metals and method for recovering valuable metals

[0001] The present invention relates to waste batteries, and more specifically to a composition for recovering valuable metals recovered from waste battery recycling, a method for recovering the same, reactants, crushed valuable metals, and a method for recovering valuable metals.

[0002] The present invention claims priority based on Korean Patent Application No. 10-2024-0191905 filed on December 19, 2024, the entire contents of said application incorporated herein by reference.

[0003] As global demand for electric vehicles (EVs) intensifies, the issue of disposing of waste batteries generated from these vehicles is emerging as a social concern. Lithium-ion batteries, which serve as the primary raw material for these waste batteries, contain organic solvents, explosive substances, and heavy metals such as Ni, Co, Mn, Fe, and P. However, Ni, Co, Mn, Fe, P, and Li are valuable metals with high scarcity value, making the recovery and recycling processes for lithium-ion batteries after disposal a critical area of ​​research.

[0004] Specifically, the lithium secondary battery comprises copper and aluminum used as current collectors, oxides containing Li, Ni, Co, Mn, Fe, and P constituting the cathode material, and graphite and Si used as the anode material, and includes a separator that separates the cathode material and the anode material, and an electrolyte injected into the separator. The solvent used as the solvent and salt constituting the electrolyte mainly consists of a mixture of carbonate organic materials such as ethylene carbonate and propylene carbonate.

[0005] To utilize the aforementioned waste batteries, interest is emerging in waste battery recycling processes that involve crushing the waste batteries to produce intermediate materials such as shredded waste batteries or black powder, followed by subsequent processing to recover valuable metals. Specifically, the major components of waste batteries consist of expensive valuable metal elements such as Ni, Co, Mn, Li, Fe, and P.

[0006] The above waste battery is, for example, a secondary battery that has reached the end of its lifespan after being used for a cycle of 5 to 10 years, and recycling the main components of the above waste battery is absolutely necessary from an environmental and cost perspective. The above waste battery undergoes conventional crushing, grinding, or sorting processes to produce a mixture of cathode and anode materials in the form of black powder, which is an intermediate product.

[0007] Methods for recovering valuable metals from the black powder are broadly classified into wet and dry processes. The wet process involves using acid to dissolve components within the raw material, primarily using sulfuric acid, and dissolving metal components within the raw material through a leaching process. Key process parameters include pH and temperature, and the particle size of the raw material also has a significant impact.

[0008] The process involves selectively extracting specific components from the leached valuable metals, a process called solvent extraction. The solvent extraction process utilizes an extractant capable of selectively extracting components based on pH. The selectively extracted components are then subjected to a final crystallization process to produce high-purity metal sulfates, which are subsequently sold as products. During this series of processes, wastewater and waste coal dust are generated as waste at the water discharge facility.

[0009] In addition, the above dry process involves heat treatment of the black mass at high temperatures to form valuable metals in the form of alloys rather than oxides. For example, an alloy of nickel and cobalt is formed through heat treatment at high temperatures. The alloy obtained in this way is also recycled as a raw material for batteries through a wet process, such as leaching or extraction. Key factors in this process include pH, temperature, and the type of oxidizer. In the case of alloys produced through the dry process, the alloy particle size can also act as a major factor in the efficiency of the wet process.

[0010] Generally, as the particle size of the raw material increases, the efficiency of the leaching process decreases, so it is important to obtain fine particles; however, since the size and shape of the raw material affect the screening process, it is necessary to control the optimal particle size and shape.

[0011] The objective of the present invention is to provide a valuable metal recovery composition capable of maximizing efficiency in wet leaching and screening processes.

[0012] Another objective of the present invention is to provide a method for recovering valuable metals that is simple, economical, and can maximize efficiency in wet leaching and screening processes.

[0013] A valuable metal recovery composition according to one embodiment of the present invention comprises a magnetic material; and a non-magnetic material; and satisfies Formula 1 below.

[0014] [Equation 1]

[0015] 0 < [Mn] B / [Mn] A < 19

[0016] (In Equation 1 above, [Mn] A and [Mn] B represents the wt% content of Mn in the non-magnetic material and the magnetic material, respectively.)

[0017] The above composition can satisfy Formula 2 below.

[0018] [Equation 2]

[0019] 0 < [Co] A / [Co] B ≤ 0.4

[0020] (In the above 2 [Co] A and [Co] B represents the wt% content of Co in the non-magnetic material and the magnetic material, respectively.)

[0021] The above non-magnetic material may satisfy at least one of the following formulas 3 to 5.

[0022] [Equation 3]

[0023] 0 < ([Ni] A + [Co] A ) / [Mn] A ≤ 1.5

[0024] [Equation 4]

[0025] 0 < [Ni] A / [Mn] A < 0.8

[0026] [Equation 5]

[0027] 0 < [Co] A / [Mn] A < 0.8

[0028] (In the above Equations 3 to 5, [Ni] A , [Co] A and [Mo] A Each refers to the wt% content of Ni, Co, and Mn in the above-mentioned non-magnetic material.)

[0029] The above non-magnetic material may include manganese oxide.

[0030] The above non-magnetic material may contain Mn in the form of manganese oxide.

[0031] The above manganese oxides are MnO, Mn3O4, Mn2O3, MnO2, MnO3, Mn2O7, Mn5O8, Mn7O 12 , Mn7O 13 Or it may include a combination of these.

[0032] The above composition may be in the form of flakes.

[0033] A method for recovering valuable metals according to another embodiment of the present invention comprises: a step of dry heat treating a waste battery crush to form a high-temperature reduction reaction product; and a step of magnetically separating the high-temperature reduction reaction product to obtain a magnetic material and a non-magnetic material; wherein the dry heat treatment is performed at a temperature at which at least a portion of the waste battery crush begins to be reduced.

[0034] The temperature at which the above reduction begins can be 700 to 1,250°C.

[0035] The above dry heat treatment can be carried out at a heating rate of 3°C or more per minute.

[0036] The above dry heat treatment can be carried out in a temperature range satisfying the following Equation 6.

[0037] [Equation 6]

[0038] 700 ≤ T=(1000 + 250) × exp((0.0001 × [Cu]) + (-0.007 × [Al])) ≤ 1250

[0039] (In Equation 6 above, [Al] is the content of Al (weight%) contained in the crushed waste battery, [Cu] is the content of Cu (weight%) contained in the crushed waste battery, and the unit of the heat treatment condition is °C)

[0040] The above magnetic separation can be carried out at 1,000 gauss or more.

[0041] The above may further include a step of grinding before magnetic separation.

[0042] A valuable metal recovery composition according to one embodiment of the present invention can maximize the efficiency of wet leaching and the efficiency of the screening process by including Ni and Co in high amounts and Mn in low amounts.

[0043] A method for recovering valuable metals according to another embodiment of the present invention performs a step of dry heat treatment at a temperature at which a portion of the crushed material begins to be reduced, thereby making the process simple and economical and maximizing the efficiency of wet leaching and the efficiency of the screening process.

[0044] Figures 1a and 1b are scanning electron microscope (SEM) images of the valuable metal recovery compositions of Example and Comparative Example 1.

[0045] Figures 2a and 2b are X-ray diffraction (XRD) analysis graphs of an example.

[0046] Figures 3a and 3b are X-ray diffraction (XRD) analysis graphs of Comparative Example 2.

[0047] Terms such as first, second, and third are used to describe various parts, components, regions, layers, and / or sections, but are not limited thereto. These terms are used solely to distinguish one part, component, region, layer, or section from another part, component, region, layer, or section. Accordingly, the first part, component, region, layer, or section described below may be referred to as the second part, component, region, layer, or section without departing from the scope of the present invention.

[0048] The technical terms used herein are for the reference of specific embodiments only and are not intended to limit the invention. The singular forms used herein include plural forms unless phrases clearly indicate otherwise. As used in the specification, the meaning of "comprising" specifies certain characteristics, areas, integers, steps, actions, elements, and / or components, and does not exclude the presence or addition of other characteristics, areas, integers, steps, actions, elements, and / or components.

[0049] When it is stated that one part is "above" or "on" another part, it may be directly above or on the other part, or other parts may be involved in between. In contrast, when it is stated that one part is "directly above" another part, no other parts are interposed in between.

[0050] Unless otherwise defined, all terms used herein, including technical and scientific terms, have the same meaning as generally understood by those skilled in the art to which this invention pertains. Terms defined in commonly used dictionaries are further interpreted to have meanings consistent with relevant technical literature and the present disclosure, and are not interpreted in an ideal or highly formal sense unless otherwise defined.

[0051]

[0052] Valuable metal recovery composition

[0053] A valuable metal recovery composition according to one embodiment of the present invention can maximize the efficiency of wet leaching and the efficiency of the screening process by including Ni and Co in high amounts and Mn in low amounts.

[0054] In one embodiment, the valuable metal recovery composition comprises a magnetic material; and a non-magnetic material; and may satisfy at least one of the following formulas 1 and 2.

[0055] [Equation 1]

[0056] 0 < [Mn] B / [Mn] A < 19

[0057] [Equation 2]

[0058] 0 < [Co] A / [Co] B ≤ 0.4

[0059] [Mn] in Equations 1 and 2 above A and [Co] Arepresents the wt% content of Mn and Co in the above-mentioned non-magnetic material, respectively, and [Mn] B and [Co] B represents the wt% content of Mn and Co in the magnetic material, respectively.

[0060] Equation 1 above is the ratio of Mn in the magnetic material to Mn in the non-magnetic material, and Equation 2 above is the ratio of Co in the non-magnetic material to Co in the magnetic material, which may be an indicator indicating that the magnetic material has a high Co content and a low Mn content.

[0061] Specifically, the above formula 1 may be greater than 0 and less than or equal to 18, greater than 0 and less than or equal to 16, greater than 0 and less than or equal to 14, greater than 0 and less than or equal to 12, greater than 0 and less than or equal to 10, greater than 0 and less than or equal to 8, greater than 0 and less than or equal to 6, greater than 0 and less than or equal to 4, greater than 0 and less than or equal to 3, greater than 0 and less than or equal to 3.5, greater than 0 and less than or equal to 3, greater than 0 and less than or equal to 2.5, and greater than 0 and less than or equal to 2.

[0062] By satisfying the aforementioned range of Equation 1, the magnetic material contains less Mn and the non-magnetic material contains more Mn, thereby improving the efficiency of separating or leaching valuable metals in subsequent processes. If Equation 1 exceeds the upper limit of the aforementioned range, Mn is excessively contained in the magnetic material, and thus the aforementioned advantages cannot be realized. Furthermore, theoretically, Equation 1 cannot reach zero, and since it is advantageous as the amount of Mn increases within the non-magnetic material, no particular restriction is placed on the lower limit.

[0063] Specifically, the above formula 2 may be greater than 0 and less than or equal to 0.38, greater than 0 and less than or equal to 0.36, greater than 0 and less than or equal to 0.34, greater than 0 and less than or equal to 0.32, greater than 0 and less than or equal to 0.3, greater than 0 and less than or equal to 0.29, greater than 0 and less than or equal to 0.28, greater than 0 and less than or equal to 0.27, greater than 0 and less than or equal to 0.26, greater than 0 and less than or equal to 0.25, and greater than 0 and less than or equal to 0.24.

[0064] By satisfying the aforementioned range of Equation 2, the magnetic material contains a large or small amount of Co, and the non-magnetic material contains a small amount of Co, thereby improving the efficiency of separating or leaching valuable metals in subsequent processes. If Equation 2 exceeds the upper limit of the aforementioned range, Co is excessively contained in the non-magnetic material, and thus the aforementioned advantages cannot be realized. Furthermore, theoretically, Equation 2 cannot reach zero, and since it is advantageous as the amount of Co within the magnetic material increases, no particular restriction is placed on the lower limit.

[0065] In one embodiment, the non-magnetic material may satisfy at least one of the following formulas 3 to 5.

[0066] [Equation 3]

[0067] 0 < ([Ni] A + [Co] A ) / [Mn] A ≤ 1.5

[0068] [Equation 4]

[0069] 0 < [Ni] A / [Mn] A < 0.8

[0070] [Equation 5]

[0071] 0 < [Co] A / [Mn] A < 0.8

[0072] [Ni] in Equations 3 to 5 above A , [Co] A and [Mo] A Each refers to the wt% content of Ni, Co, and Mn in the above-mentioned non-magnetic material.

[0073] The above Equations 3 to 5 are, respectively, the ratio of the content of Ni and Co to the content of Mn in the non-magnetic material, the ratio of the content of Ni, and the ratio of the content of Co, and may serve as indicators for the efficiency of recovering valuable metals.

[0074] Specifically, the above formula 3 may be greater than 0 and less than or equal to 1.4, greater than 0 and less than or equal to 1.3, greater than 0 and less than or equal to 1.2, greater than 0 and less than or equal to 1.1, greater than 0 and less than or equal to 1, greater than 0 and less than or equal to 0.9, greater than 0 and less than or equal to 0.8, greater than 0 and less than or equal to 0.7, greater than 0 and less than or equal to 0.6, greater than 0 and less than or equal to 0.5, greater than 0 and less than or equal to 0.4, greater than 0 and less than or equal to 0.3, greater than 0 and less than or equal to 0.25, greater than 0 and less than or equal to 0.2, greater than 0 and less than or equal to 0.18, and greater than 0 and less than or equal to 0.16.

[0075] By satisfying the aforementioned range of Equation 3, the non-magnetic material contains a high content of Mn, and the magnetic material contains a low content of Mn compared to Ni and Co, thereby improving the efficiency of separating or leaching valuable metals in subsequent processes. If Equation 3 deviates from the upper limit of the aforementioned range, it means that the content of Ni and Co in the non-magnetic material is excessively high, or in other words, that the content of Mn in the magnetic material is high. That is, the aforementioned advantages cannot be realized. Furthermore, theoretically, Equation 3 cannot reach zero, and since it is advantageous as the content of Ni and Co in the non-magnetic material decreases, no particular restriction is placed on the lower limit.

[0076] Specifically, at least one of the above formulas 4 and 5 may be independently greater than 0 to 0.7, greater than 0 to 0.6, greater than 0 to 0.5, greater than 0 to 0.4, greater than 0 to 0.3, greater than 0 to 0.25, greater than 0 to 0.2, greater than 0 to 0.18, greater than 0 to 0.16, greater than 0 to 0.14, greater than 0 to 0.12, and greater than 0 to 0.1.

[0077] By satisfying at least one of the above Equations 4 and 5 within the aforementioned range, the non-magnetic material contains a high content of Mn, while the magnetic material contains a low content of Mn relative to at least one of Ni and Co, thereby improving the efficiency of separating or leaching valuable metals in subsequent processes. If the above Equations 4 and 5 fall outside the upper limit of the aforementioned range, it implies that the content of Ni and Co within the non-magnetic material is excessively high, or in other words, that the content of Mn within the magnetic material is high. That is, the aforementioned advantages cannot be realized. Furthermore, theoretically, Equations 4 and 5 cannot reach zero, and since it is advantageous as the content of Ni and Co within the non-magnetic material decreases, no particular restriction is placed on the lower limit.

[0078] In one embodiment, the non-magnetic material may include manganese oxide. In other words, Mn present in the non-magnetic material may exist in the form of manganese oxide. This can serve as a configuration that improves screening or leaching efficiency when separating the magnetic material from the valuable metal recovery composition to proceed with a subsequent process.

[0079] In one embodiment, the manganese oxide is MnO, Mn3O4, Mn2O3, MnO2, MnO3, Mn2O7, Mn5O8, Mn7O 12 , Mn7O 13 Or, a combination thereof may be included. However, it is not limited thereto, and manganese oxides of other compositions may be further included according to the common sense of a person skilled in the art without compromising the purpose of the present invention.

[0080] In one embodiment, the valuable metal recovery composition may be in the form of flakes. The flake shape may be formed by performing a high-temperature reduction heat treatment process on a battery or battery crushed material obtained by crushing the battery. Specifically, the valuable metal recovery composition may include a plurality of reactants having the flake shape.

[0081] The composition having the flake shape described above may partially maintain the shape of the current collector within the battery or battery crush by performing a high-temperature reduction heat treatment process on the battery or battery crush at a temperature at which lithium begins to be reduced. By including the composition having the flake shape in the valuable metal recovery composition, separation from graphite during particle size and magnetic separation in the subsequent separation process may be more advantageous, ultimately providing excellent benefits for improving the recovery rate of valuable metals.

[0082] Specifically, if the above composition does not have a flake shape, fine metal particles are formed on the graphite surface. Consequently, it is difficult to physically separate the metal particles from the graphite surface, and since the size difference with the graphite is not significant, separation is also difficult using methods such as particle size sorting. Furthermore, when the metal particles adhere to the graphite surface, they become magnetic, which causes a problem of reducing the recovery rate of valuable metals in the subsequent magnetic separation stage.

[0083] The flake shape may refer to an irregular shape. Specifically, the irregular shape may refer to a shape including a pointed region. In one embodiment, the flake shape may be characterized in that at least one of the angles at which two outlines of the valuable metal recovery composition meet is 90° or less. For example, when a plurality of outlines are drawn on the outer surface of the valuable metal recovery composition in an SEM image of the valuable metal recovery composition, the shape may be characterized in that there are multiple regions where the angle at which two outlines meet is 90° or less among the plurality of outlines.

[0084] In one embodiment, the particle size of the composition may satisfy a range of 100 to 1000 μm. Specifically, the composition may include i) a composition having a first particle size of 100 to 150 μm, ii) a composition having a second particle size of 150 to 250 μm, iii) a composition having a third particle size of 250 to 500 μm, and iv) a composition having a fourth particle size of 500 to 1000 μm. The particle size of the composition may refer to an average particle size (D50).

[0085] In one embodiment, based on 100% of the composition, the composition having the first particle size may be 8 to 19%, the composition having the second particle size may be 12 to 25%, the composition having the third particle size may be 30 to 38%, and the composition having the fourth particle size may be the remainder. The % may be based on volume.

[0086] When the particle size of the aforementioned composition is formed as fine particles of less than 100 μm, there is a problem in that separation from graphite is not easy. However, when the particle size of the aforementioned composition is formed as large as 100 μm or more, the particle size of the metal droplet formed on the flake is much finer than that of the flake, so there is an advantage of high leaching efficiency.

[0087] Specifically, satisfying the aforementioned range for the particle size of the composition provides the advantage of facilitating leaching and screening processes in subsequent stages. If the particle size of the composition is excessively coarse, the amount of valuable magnetic metal within the flakes is relatively small, leading to a problem where the metal recovery rate decreases even if magnetism is present. If the particle size of the composition is excessively small, the structure of the crushed material collapses, forming fine particles similar to dust, resulting in inferior screening and leaching efficiency for magnetic separation.

[0088]

[0089] Method for recovering valuable metals

[0090] A method for recovering valuable metals according to another embodiment of the present invention performs a step of dry heat treatment at a temperature at which a portion of the crushed material begins to be reduced, thereby making the process simple and economical and maximizing the efficiency of wet leaching and the efficiency of the screening process.

[0091] In one embodiment, a method for recovering valuable metals comprises the steps of: dry heat treating a waste battery crush to form a high-temperature reduction reaction product; and magnetically separating the high-temperature reduction reaction product to obtain a magnetic material and a non-magnetic material; wherein the dry heat treatment may be performed at a temperature at which at least a portion of the waste battery crush begins to be reduced.

[0092] As the method for recovering valuable metals according to the present invention is performed at a temperature at which at least a portion of the battery or the battery crushed material begins to be reduced, the resulting material has a flake shape as described above, and the detailed description of the valuable metal recovery composition may refer to the aforementioned content to the extent that it is not contradictory.

[0093] In the step of preparing the battery, the battery may include end-of-life batteries, cathode materials such as scrap, jelly rolls, and slurries constituting the waste battery, defective products generated during the manufacturing process, residues within the manufacturing process, and generated debris, for example, waste materials within the manufacturing process of a lithium-ion battery. In this way, the waste battery can be prepared as the battery to recycle the battery.

[0094] In one embodiment, the step of preparing the battery may include a pretreatment step for the battery. Specifically, by including the pretreatment step, explosive substances such as the electrolyte within the battery can be removed to increase safety in subsequent processes and maximize the efficiency of recovery and separation of valuable metals.

[0095] In one embodiment, the step of pre-treating the battery may include a step of discharging the battery. The step of discharging the battery may pre-treat the battery by various methods, such as water discharge or electric discharge, as a non-limiting example.

[0096] When the step of discharging the battery is performed by electric discharge, the voltage of the battery can be reduced to control the voltage of the cell within the battery. For example, the voltage of the battery can be controlled to a voltage of 0 to 4.2 V relative to the cell within the battery.

[0097] The step of treating the battery at a low temperature below a minimum temperature according to the voltage of the battery may be a step of freezing and stabilizing the electrolyte contained within the battery. By treating the battery below a minimum temperature, it is possible to prevent a fire caused by hazardous materials, such as the electrolyte, when the battery is crushed.

[0098] In one embodiment, the low-temperature treatment step may be a step of treating the battery at 10°C or lower. Specifically, when the voltage of the battery is 1.0 V or lower, the low-temperature treatment step may be performed on the battery at a temperature of 0°C or lower. More specifically, when the voltage of the battery is 1.5 to 2.0 V, the battery may be low-temperature treated at a temperature of -15°C or lower. More specifically, when the voltage of the battery is approximately 2.5 V, the battery may be low-temperature treated at a temperature of -30°C or lower. More specifically, when the voltage of the battery is 3 to 3.5 V, the battery may be low-temperature treated at a temperature of -50°C or lower.

[0099] In this way, the battery has the advantage of being able to be safely crushed in the crushing process by performing low-temperature treatment within a specific temperature range according to the cell reference voltage of the battery.

[0100] As the step of performing low-temperature treatment on the battery within the above temperature range is performed, the voltage remaining in minutely within the battery, for example, about 2 V to 3 V, is reduced to near 0 V. Consequently, even if a short circuit occurs where the positive and negative electrodes come into direct contact, no battery reaction occurs, so the battery temperature does not increase, and thus no gas generation or combustion of the electrolyte occurs. Furthermore, since the electrolyte is in a frozen state or a state where vaporization is suppressed, the mobility of lithium ions is very low, so the current conduction characteristics due to the movement of lithium ions can be significantly reduced, and since vaporization of the electrolyte does not occur, flammable gases such as ethylene, propylene, and hydrogen can not be generated.

[0101] If the above low-temperature treatment step is performed at a temperature higher than the above temperature range, the voltage remaining inside the battery does not drop to 0 V, which may cause a battery reaction due to a short circuit, and the electrolyte is not completely frozen, making it unsuitable. In this way, the battery treatment method includes a low-temperature treatment step before crushing a battery such as a lithium secondary battery, thereby preventing the risk of fire that may occur during the battery crushing process.

[0102] The step of crushing the frozen battery may refer to a process of applying impact or pressure to the battery so that a portion of the battery detaches from the battery. In one embodiment, the step of crushing the battery may refer to a process of grinding the battery, a process of cutting the battery, a process of compressing the battery, and any combination thereof. Specifically, the crushing step may include any process that destroys the battery to obtain small-sized crushed material.

[0103] In one embodiment, the step of crushing the battery may include all processes of compressing the frozen battery or destroying the battery by applying an external force such as shear force or tensile force. The step of crushing the battery may be carried out, for example, using a crusher.

[0104] In one embodiment, the step of crushing the battery may be performed at least once. Specifically, the crushing step may be performed at least once, either continuously or discontinuously.

[0105] In one embodiment, the step of crushing the battery may be carried out under conditions of supplying an inert gas, carbon dioxide, nitrogen, water, or a combination thereof, or under vacuum conditions of 100 torr or less. For example, when the process of freezing the battery is carried out by cooling it in a temperature range of -60 to -20°C, or under the aforementioned conditions, the supply of oxygen can be suppressed to prevent the electrolyte from reacting with oxygen, thereby preventing an explosion caused by this, and the vaporization of the electrolyte can be suppressed so as not to generate flammable gases such as ethylene, propylene, or hydrogen.

[0106] In one embodiment, the step of crushing the battery may be performed such that the maximum size of the battery crushed material is 100 mm or less. Specifically, the size of the battery crushed material may be 50 mm or less. If the maximum size of the battery crushed material is 100 mm or more, the heat generated due to instability as the battery crushed material is crushed rises to a temperature range of 120°C, which is the average vaporization temperature of the electrolyte, and safety issues such as fire may occur.

[0107] In one embodiment, the battery fragment obtained through the step of crushing the battery may have a layered structure comprising a separator having a positive or negative electrode laminated on at least one surface. Specifically, the layered structure may include a configuration in which a positive or negative electrode is included on one surface or both surfaces of the separator based on the separator. More specifically, the number of layers of the layered structure may correspond to the number of separators. For example, the layered structure may include any one of a positive-separator-negative electrode, positive-separator, separator-positive electrode, separator-negative electrode, or negative-separator, and for example, a positive-separator-negative electrode-separator-positive-separator-negative electrode structure may have a three-layer layered structure. Specifically, the unit battery fragment may have a predetermined thickness in the thickness direction as at least one layer is laminated.

[0108] In one embodiment, the battery crusher may have a layered structure having a stacked structure of one or more to seven layers. Specifically, the layered structure may have a stacked structure of one or more to five layers. As the layered structure is stacked within the above range, the temperature rise of the crusher is minimized, and the heating time can be appropriately taken. If the layered structure is stacked thicker than the upper limit of the above range, the temperature rise increases excessively, and the heating time also increases, leading to a problem of causing a fire as combustion occurs.

[0109] In one embodiment, the size of the battery shredder may be 100 mm or less based on the major axis, which is the longest axis among the width, length, and height directions. Specifically, the size of the battery shredder may be 50 mm or less. By satisfying the aforementioned range for the size of the battery shredder, the possibility of fire occurring in subsequent processes can be reduced. If the size of the unit battery shredder is excessively large, there is a problem in that the temperature of the battery shredder itself rises above 100°C, increasing the likelihood of fire.

[0110] The step of high-temperature heat treatment of the battery or the battery fragments obtained by crushing the battery may be performed at a temperature at which at least a portion of the battery or the battery fragments begins to be reduced. Specifically, the heat treatment process may be performed at a temperature above which the positive electrode current collector is deformed, above which partial melting of the negative electrode current collector occurs, and below which lithium vaporizes and is lost.

[0111] In one embodiment, the temperature at which reduction begins may be 700 to 1,250°C. Specifically, the temperature may be 800 to 1,200°C, more specifically, in the range of 900 to 1,200°C.

[0112] As the above dry heat treatment step is performed within the aforementioned temperature range, a flake-shaped reactant can be easily formed in which the alloys constituting the anode active material partially melt while partially maintaining the shape of the current collector. Furthermore, since Mn remains as manganese oxide without forming an alloy with Ni or Co, the magnetic material can improve screening and leaching efficiency by containing high amounts of Ni and Co and low amounts of Mn. For a detailed explanation of this, refer to the aforementioned valuable metal recovery composition.

[0113] If the above temperature exceeds the upper limit of the aforementioned range, the lithium vaporizes and is lost, resulting in a decrease in the lithium recovery rate; furthermore, Mn forms an NCM alloy, and since Mn cannot be separated into a non-magnetic material, the aforementioned advantages cannot be realized. Additionally, if the above temperature exceeds the lower limit of the aforementioned range, there is a problem in that the structure of the current collector is not deformed or the melting of the alloy is not performed smoothly.

[0114] In one embodiment, the dry heat treatment step may be performed at a heating rate of 3°C or more per minute. Specifically, the heating rate may be 5°C or more per minute, and more specifically 8 to 20°C. By performing the dry heat treatment step within the heating rate range, there is an advantage that nucleation is easier than growth of the alloy.

[0115] If the aforementioned heating rate range exceeds the lower limit of the aforementioned range, smooth nucleation does not occur, and growth becomes relatively easy, leading to the problem of metal particles becoming coarse; the formation of such coarse alloys results in a decrease in the leaching rate in subsequent processes. If the aforementioned heating rate range exceeds the upper limit of the aforementioned range, the distortion of the current collector that holds the flake structure accelerates, forming relatively fine flakes and causing a problem of reduced separation efficiency from carbon.

[0116] In one embodiment, the dry heat treatment step may be performed under conditions where the O2 volume fraction is less than 5%. In one embodiment, the high-temperature heat treatment step may be performed in an atmosphere containing an inert gas, and the inert gas may be performed under conditions where the volume fraction is less than 1%. The inert gas may include at least one of argon and nitrogen, and may be, for example, argon gas. By performing the high-temperature heat treatment step at the aforementioned oxygen volume fraction and inert gas volume fraction, the reduction process is easily performed, allowing for the effective recovery of valuable metals containing valuable metals as a component. Furthermore, if the oxygen content deviates from the aforementioned range, an excess amount of oxygen combines with the battery crushed material components within the reduction reaction to form carbon dioxide, which is gasified along with lithium, and consequently, there is a problem in that the recovery of lithium, a valuable metal, is not easy.

[0117] In one embodiment, the dry heat treatment step can be performed in a temperature range satisfying the following Equation 6.

[0118] [Equation 6]

[0119] 700 ≤ T=(1000 + 250) × exp((0.0001 × [Cu]) + (-0.007 × [Al])) ≤ 1250

[0120] In the above Equation 6, [Al] is the content of Al (weight%) contained in the battery or battery crushed material, [Cu] is the content of Cu (weight%) contained in the crushed material, and the unit of the heat treatment condition is °C.

[0121] T in Equation 6 above may be an indicator regarding the formation of reactants having a flake shape and the partial melting of the alloy. Since changes in the physical phenomena of the structure occur at relatively higher temperatures for Cu compared to Al, the heat treatment temperature increases as the Cu content increases. Conversely, since an increase in the Al content causes a relative decrease in the Cu content, the heat treatment temperature must be lowered. Based on this, the relationship between the content of Cu and Al was derived as Equation 6. By satisfying the aforementioned range for Equation 6, a valuable metal recovery composition in which the alloy partially melts in reactants having a flake shape can be easily realized, thereby increasing the leaching and separation efficiency of valuable metals in subsequent processes.

[0122] At this time, in the above Equation 6, the content of Al may be 1 wt% to 75 wt%, specifically 73 wt% or less, and the content of Cu may be 70 wt% or less. By satisfying the aforementioned ranges for the content of Al and Cu in the battery or battery crushed material, it may be possible to realize a composition in which the alloy is partially melted in a reactant having a flake shape.

[0123] If the above Equation 6 exceeds the upper limit of the aforementioned range, there is a problem in that the formation of flakes collapses excessively and becomes fine. If the above Equation 6 exceeds the lower limit of the aforementioned range, there is a problem in that the shape of the coarse crushed material is maintained and the alloy phase is not formed.

[0124] In one embodiment, the high-temperature reduction reactant may further include a grinding step prior to the magnetic separation, wherein the grinding method may be either dry or wet grinding, such as a cup-mill, ball-mill, or attrition mill. If the grinding step is further included, the valuable metal recovery composition is finely divided into magnetic and non-magnetic powders, thereby facilitating separation into magnetic and non-magnetic materials during magnetic separation.

[0125] In one embodiment, the step of magnetic separation after grinding the high-temperature reduction reactant may be carried out at a magnetic force of 1,000 gauss or more. Specifically, the magnetic force strength may be 1,000 to 3,000 gauss or 1,500 to 2,500 gauss. When the magnetic force strength satisfies the aforementioned range, the obtained non-magnetic material satisfies Equations 1 to 3 described above, thereby increasing the separation and leaching efficiency in subsequent processes. If the value exceeds the upper limit of the aforementioned range, costs may increase due to the use of an excessively large magnetic force. Furthermore, if the value exceeds the lower limit of the aforementioned range, a problem arises in which the efficiency of separating magnetic and non-magnetic materials decreases.

[0126] In one embodiment, the magnetic separation may be performed dry. Specifically, the magnetic separation may use either a dry drum-type magnetic separator or a dry conveyor belt-type magnetic separator.

[0127] In another embodiment, the magnetic separation may be performed wet. Specifically, the magnetic separation may be performed by immersing the battery crushed material in a water bath or a batch containing a liquid material, and then performing magnetic separation using a magnet. Specifically, the wet magnetic separation may be performed under conditions where the pulp density, which indicates the concentration of solids, is 10 to 50%. Specifically, the pulp density may be performed at 20 to 40%. The wet magnetic separation has the advantage of improved separation efficiency compared to the dry magnetic separation.

[0128] In one embodiment, a step of particle size separation may be further included before or after the magnetic separation step. The particle size separation method separates particles according to their size or diameter and may include various methods, for example, using a sieve for separation.

[0129]

[0130] Preferred embodiments and comparative examples of the present invention are described below. However, the following examples are merely preferred embodiments of the present invention, and the present invention is not limited to the following examples.

[0131]

[0132] Examples

[0133] (Battery preparation step) A cell-based 3.6 V battery was prepared for an NCM622 lithium-ion battery having approximately 4.2 V when the SOC is 100%. The battery was discharged to 0.5 V or lower within 2 hours by applying a current of 5 A to the initial battery. Afterward, the battery was subjected to cryogenic treatment at 60 ℃ for 24 hours.

[0134] (Step of shredding the battery) The battery was shredded using a 2-axis 2-stage shredder to a particle size range of 5 to 80 mm. The shredded battery material had a layered structure in which the positive electrode, negative electrode, and separator were stacked in sequence, and the layered structure was stacked in at least one layer, and the size of the battery shred was 100 mm or less. The size of the battery shred refers to the length based on the major axis among the width, length, and height of the battery shred. The shredding was completed within 5 minutes for the module and within 3 minutes for the cell.

[0135] (Step of reducing the battery to a high temperature) The battery was reduced to a high temperature in a high-temperature reduction furnace at a temperature at which at least a portion of the battery, for example, battery crushed material, begins to be reduced. Specifically, the battery was heated in a high-temperature reduction furnace at a heating rate of 3°C or more per minute, and after reaching 1,100°C, dry heat treatment was maintained for 2 hours. At this time, the process was carried out in an atmosphere of less than 5% O2 and less than 1% Ar. The aforementioned heat treatment conditions were performed at a temperature above which deformation is applied to the positive current collector, within a temperature range where some of the metal, such as copper, partially melts, and within a range where lithium is not lost through vaporization.

[0136] (Step of obtaining a valuable metal recovery composition as a magnetic and non-magnetic material) The valuable metal recovery composition obtained through the step of reducing the battery at a high temperature was subjected to magnetic separation with a magnetic force of 1,000 gauss or more in a dry environment to obtain a magnetic and non-magnetic material.

[0137]

[0138] Comparative Example 1

[0139] The process was carried out in the same manner as the example, except that the heat treatment temperature in the step of reducing the battery to a high temperature was performed at a low temperature of 700℃ or lower.

[0140]

[0141] Comparative Example 2

[0142] In the step of reducing the battery to a high temperature, the process was carried out in the same manner as the example, except that the heat treatment was performed at a high temperature of 1,250°C or higher.

[0143]

[0144] Evaluation example

[0145] (1) SEM (scanning electron microscope) image analysis

[0146] Figures 1a and 1b are scanning electron microscope (SEM) images of the valuable metal recovery compositions of Example and Comparative Example 1.

[0147] Referring to FIG. 1a, it can be seen that a valuable metal recovery composition according to one embodiment of the present invention forms a composition having a plurality of flake shapes with a size of 100 to 1000 μm.

[0148] In contrast, as shown in Fig. 1b, it can be seen that a valuable metal recovery composition with a size far exceeding 1000 μm is formed. In this case, subsequent processes such as screening and leaching cannot be carried out immediately, and additional processes are required. That is, it can be seen that when the dry heat treatment temperature is 700°C or lower, a high-temperature reduction reaction product is formed that cannot exhibit the aforementioned flake shape and the resulting advantages.

[0149]

[0150] (2) XRD (x-ray diffraction) analysis

[0151] FIGS. 2a and 2b are X-ray diffraction (XRD) analysis graphs of the example, and FIGS. 3a and 3b are X-ray diffraction (XRD) analysis graphs of Comparative Example 2.

[0152] XRD analysis was performed on the above Example and Comparative Example 2 and is shown in FIGS. 2a, 2b, 3a, and 3b. FIGS. 2a and 3a are graphs of the magnetic materials of the Example and Comparative Example 2, respectively, and FIGS. 2b and 3b are graphs of the non-magnetic materials of the Example and Comparative Example, respectively.

[0153] Looking at Fig. 2a, it can be seen that the magnetic material of the example contains Mn in the form of manganese oxide of MnO, and Ni and Co in the form of a Ni-Co alloy. Through this, it can be seen that the example does not contain Mn in the form of a magnetic alloy.

[0154] Looking at Fig. 2b, it can be seen that the non-magnetic material of the example contains Mn in the form of manganese oxide of MnO, and that there is no material containing Ni and Co. This means that most of the Ni and Co in the valuable metal recovery composition of the example are contained in the magnetic material, and it can be inferred that the magnetic material contains Ni and Co in high amounts.

[0155] Looking at Fig. 3a, it can be seen that the magnetic material of Comparative Example 2 contains Mn in the form of an MnNi3 alloy, and that MnO is not present. In other words, this means that in Comparative Example 2, Mn is included in the form of an alloy that exhibits magnetic force. Also, looking at Fig. 3b, it can be seen that the non-magnetic material of Comparative Example 2 does not contain Ni, Co, or Mn. When considering all of this, if the dry heat treatment temperature is 1,250°C or higher, Mn is formed as an NCM alloy rather than an oxide of MnO, and thus Mn cannot be separated into a non-magnetic material, so the aforementioned advantages cannot be achieved.

[0156]

[0157] (3) ICP (inductively coupled plasma) analysis

[0158] Table 1 below shows the component content of the magnetic and non-magnetic materials of Example and Comparative Example 2. The component content in Table 1 below is the result of analysis using an ICP device after completely dissolving the solid sample through pretreatment.

[0159] Elemental Content (wt%) Preliminary Comparative Example Dimagnetic Nonmagnetic Magnetic Nonmagnetic Li 3.9 3.4 3.7 3.4 Al 10.8 10.7 7.9 10.7 Cu 7.4 5 4.4 10.3 3 48.4 Mn 10.7 6.3 9.5 20.5 Ni 3 2.4 0.5 3 8.4 0.4 Co 1 3.3 0.3 9.0 10.4 (Ni+Co) / Mn 4.2 70.1 34.9 81.60 Ni / Mn 3.0 30.0 84.0 30.80 Co / Mn 1.2 40.0 50.9 50.80 [Mn] B / [Mn] A 1.719[Co]A / [Co] B 0.0230.044

[0160] Looking at Table 1 above, it can be seen that the magnetic material of the example contains Mn at a level approximately 2 to 3 wt%p lower than Co, and the non-magnetic material contains Ni and Co at 1 wt% or less. In other words, it can be seen that the magnetic material according to the example of the present invention contains Ni and Co in high amounts and Mn in low amounts, which can ultimately be inferred to maximize the efficiency of the subsequent process. In contrast, the magnetic material of Comparative Example 2 has similar Mn and Co content, and it can be seen that the non-magnetic material also contains Mn at 0.5 wt% or less. In this case, it is not possible to expect an increase in the efficiency of separating valuable metals and leaching due to the aforementioned low Mn content.

[0161] When considering the results of Table 1 above together with the XRD analysis results described above, it can be seen that through the method for recovering valuable metals according to one embodiment of the present invention, most of the Mn contained in the initial battery crushed material forms manganese oxide and is separated into a non-magnetic material, thereby consequently reducing the Mn content of the magnetic material.

[0162] The present invention is not limited to the above embodiments and can be manufactured in various different forms, and those skilled in the art will understand that the invention can be implemented in other specific forms without changing the technical concept or essential features of the invention. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive.

Claims

1. Includes a magnetic material; and a non-magnetic material; and Satisfying Equation 1 below, Valuable metal recovery composition. [Equation 1] 0 < [Mn] B / [Mn] A < 19 (In Equation 1 above, [Mn] A and [Mn] B represents the wt% content of Mn in the non-magnetic material and the magnetic material, respectively.) 2. In Paragraph 1, The above composition satisfies Formula 2 below, Valuable metal recovery composition. [Equation 2] 0 < [What] A / [What] B ≤ 0.4 (In the above 2 [Co] A and [Co] B represents the wt% content of Co in the non-magnetic material and the magnetic material, respectively.) 3. In Paragraph 1, The above non-magnetic material satisfies the following Equation 3, Valuable metal recovery composition. [Equation 3] 0 < ([Ni] A + [What] A ) / [Mn] A ≤ 1.5 (In Equation 3 above, [Ni] A , [Co] A and [Mo] A Each refers to the wt% content of Ni, Co, and Mn in the above-mentioned non-magnetic material.) 4. In Paragraph 1, The above non-magnetic material satisfies the following Equation 4, Valuable metal recovery composition. [Equation 4] 0 < [Ni] A / [Mn] A < 0.8 (In Equation 4 above, [Ni] A and [Mo] A Each refers to the wt% content of Ni and Mn in the above-mentioned non-magnetic material.) 5. In Paragraph 1, The above non-magnetic material satisfies the following Equation 5, Valuable metal recovery composition. [Equation 5] 0 < [What] A / [Mn] A < 0.8 (In Equation 5 above, [Co] A and [Mo] A Each refers to the wt% content of Co and Mn in the above-mentioned non-magnetic material.) 6. In Paragraph 1, The above non-magnetic material comprises manganese oxide, Valuable metal recovery composition.

7. In Paragraph 6, The above non-magnetic material contains Mn in the form of manganese oxide, Valuable metal recovery composition.

8. In Paragraph 6 or 7, The above manganese oxides are MnO, Mn3O4, Mn2O3, MnO2, MnO3, Mn2O7, Mn5O8, Mn7O 12 , Mn7O 13 or including a combination thereof, Valuable metal recovery composition.

9. In Paragraph 1, The above composition is in the shape of a flake, Valuable metal recovery composition.

10. A step of dry heat-treating crushed waste batteries to form a high-temperature reduction reaction product; and The method includes the step of magnetically separating the above high-temperature reduction reaction product to obtain a magnetic material and a non-magnetic material; The above dry heat treatment is carried out at a temperature in which at least a portion of the waste battery crushed material begins to be reduced. Method for recovering valuable metals.

11. In Paragraph 10, The temperature at which the above reduction begins is 700 to 1,250℃, Method for recovering valuable metals.

12. In Paragraph 10, The above dry heat treatment is carried out at a heating rate of 3°C or more per minute, Method for recovering valuable metals.

13. In Paragraph 10, The above dry heat treatment is carried out in a temperature range satisfying Equation 6 below, Method for recovering valuable metals. [Equation 6] 700 ≤ T=(1000 + 250) × exp((0.0001 × [Cu]) + (-0.007 × [Al])) ≤ 1250 (In Equation 6 above, [Al] is the content of Al (weight%) contained in the crushed waste battery, [Cu] is the content of Cu (weight%) contained in the crushed waste battery, and the unit of the heat treatment condition is °C) 14. In Paragraph 10, The above magnetic separation proceeds at 1,000 gauss or more, Method for recovering valuable metals.

15. In Paragraph 10, A further step of grinding before the above magnetic separation, Method for recovering valuable metals.

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