Complex ionic compounds, methods for making same, and their use in the recovery of metal ions - Patents.com

Abstract

To provide a complex ionic compound for recovery of metal ions, capable of simplifying the recovery process of metal ions and reducing the recovery cost of metal ions, its preparation method, and its use in the recovery of metal ions.SOLUTION: A complex ionic compound comprises a carrier including C:Na-Ni / Al2O3 composite powder, a crosslinking agent including halogen-containing siloxane of low molecular weight, and an adsorbent including 1-butyl-3-methylimidazolium hexafluorophosphate or the like, wherein the crosslinking agent is grafted onto the carrier, and the adsorbent is grafted onto the crosslinking agent.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to complex ionic compounds, methods for their preparation, and their use in the recovery of metal ions. [Background technology]

[0002] Lithium-ion batteries have long been a common power source in our daily lives thanks to their high energy density and ease of manufacture. Currently, the cathode materials for lithium-ion batteries include metal-containing materials such as lithium-cobalt, lithium-nickel, lithium-nickel-cobalt, and lithium-nickel-cobalt-manganese. The metals employed in the cathode materials (e.g., manganese, cobalt, nickel, and lithium) are derived from depleting natural resources, and the metals contained in discarded batteries may pose a risk to the environment. How to recover the metals contained in discarded batteries is one of the key challenges in environmental and sustainable development. Summary of the Invention [Problem to be solved by the invention]

[0003] The present invention provides complex ion compounds that facilitate the recovery of metal ions.

[0004] The present invention provides a method for producing complex ion compounds to enhance the recovery of metal ions.

[0005] The present invention provides the use of complex ion compounds for the recovery of metal ions, which can simplify the recovery process of metal ions and reduce the cost of recovering metal ions. [Means for solving the problem]

[0006] The composite ionic compound of the present invention comprises a carrier, a cross-linking agent grafted to the carrier, and an adsorbent grafted to the cross-linking agent.

[0007] The support of an embodiment of the present invention comprises a C:Na-Ni / Al2O3 composite powder.

[0008] In one embodiment of the present invention, the crosslinker comprises a low molecular weight halogen-containing siloxane.

[0009] In one embodiment of the present invention, the adsorbent comprises at least two of 1-butyl-3-methylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazolium tetrafluoroborate, 1-ethyl-3-methylimidazolium hexafluorophosphate, 1-butyl-3-methylimidazolium acetate, choline chloride, and glycerol.

[0010] The method for preparing the composite ionic compound of the present invention includes the steps of grafting a cross-linking agent onto a support, and grafting an adsorbent onto the cross-linking agent to form the composite ionic compound.

[0011] In one embodiment of the present invention, the method for preparing a composite ionic compound further includes forming a carrier, which includes: placing Na-Ni / Al2O3 powder in a reactor; supplying carbon dioxide and hydrogen into the reactor; and adjusting the temperature in the reactor to 400-800°C to reduce the carbon dioxide to carbon, which is then adsorbed onto Ni atoms in the Na-Ni / Al2O3 powder to form a C:Na-Ni / Al2O3 composite powder.

[0012] In one embodiment of the present invention, the crosslinking agent comprises a low carbon number chlorine-containing siloxane represented by the following formula (1): [ka] In the formula, each R is independently alkyl having 1 to 6 carbon atoms.

[0013] According to one embodiment of the present invention, the adsorbent is grafted to the chlorine (Cl) terminus of the crosslinker.

[0014] In one embodiment of the present invention, the adsorbent comprises at least two of butyl-3-methylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazolium tetrafluoroborate, 1-ethyl-3-methylimidazolium hexafluorophosphate, 1-butyl-3-methylimidazolium acetate, choline chloride, and glycerol.

[0015] The use of the composite ion compound in the recovery of metal ions of the present invention includes adding the above-mentioned composite ion compound to a recovery liquid containing metal ions so that the composite ion compound can adsorb the metal ions; separating the composite ion compound having adsorbed the metal ions; extracting the composite ion compound having adsorbed the metal ions with a solvent to separate the metal ions from the composite ion compound and extract the metal ions into the solvent; and purifying the metal ions in the solvent.

[0016] In one embodiment of the present invention, the recovery solution is a lithium ion battery recovery solution.

[0017] In one embodiment of the present invention, the metal ions include manganese (Mn) ions, cobalt (Co) ions, nickel (Ni) ions, lithium (Li) ions, or a combination thereof.

[0018] In one embodiment of the present invention, "separating the complex ionic compounds having adsorbed metal ions" is performed using a magnetic material that attracts the complex ionic compounds.

[0019] In one embodiment of the present invention, the solvent comprises ethyl acetate or methanol. [Effects of the Invention]

[0020] The adsorbent in the composite ion compound of the present invention adsorbs metal ions, so it can be used for separating and extracting metal ions to further promote the recovery of metal ions. Furthermore, the composite ion compound of the present invention is magnetic, making it easy to extract. Therefore, the metal ion recovery method of the present invention can greatly simplify the recovery process and reduce the cost of recovering metal ions.

[0021] To make the foregoing more easily understandable, several embodiments are described in detail below with reference to the drawings. [Brief explanation of the drawings]

[0022] The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the invention and, together with the description, serve to explain the principles of the invention. [Figure 1] 1 is a schematic flow chart illustrating a method for producing a composite ionic compound according to one embodiment of the present invention. [Figure 2] The decomposition potentials of two different metal ions, metal ion A and metal ion B, are shown. [Figure 3] FIG. 1 is a schematic diagram showing a potential control circuit used in electrolytic separation. DETAILED DESCRIPTION OF THE INVENTION

[0023] The embodiments of the present invention will be described in detail below, but these embodiments are merely examples and do not limit the scope of the present invention.

[0024] In this specification, the ranges indicated as "from a certain value to another value" are general expressions to avoid listing all the values ​​in this specification. Therefore, the description of a specific numerical range covers any numerical value within that range and a smaller numerical range defined by any numerical value within that range, and is equivalent to specifying that numerical value and the smaller numerical range.

[0025] FIG. 1 is a schematic flow chart illustrating a method for producing a composite ionic compound according to one embodiment of the present invention.

[0026] Please refer to FIG. 1. In the present invention, the method for producing a composite ionic compound includes the following steps, but the present invention is not limited thereto. First, in step S1, a carrier is formed. Next, in step S2, a crosslinking agent is grafted onto the carrier. In step S3, an adsorbent is grafted onto the crosslinking agent, so that the adsorbent and the carrier are bonded via the crosslinking agent to form a composite ionic compound. The steps are described in detail as follows:

[0027] In the present invention, the order of grafting the crosslinker and the adsorbent is not particularly limited. In some embodiments, the adsorbent may be grafted to the crosslinker before the crosslinker bound to the adsorbent is grafted to the support via the crosslinker terminal.

[0028] In some embodiments, the support can be a C:Na-Ni / Al2O3 composite powder. In some embodiments, the C:Na-Ni / Al2O3 composite powder can be produced by fixed bed reactor reduction. For example, forming the C:Na-Ni / Al2O3 composite powder can include placing Na-Ni / Al2O3 powder in a reactor (e.g., a fixed bed reactor) and supplying carbon dioxide and hydrogen to the reactor. The temperature in the reactor can be between 400°C and 800°C, e.g., 500°C, 600°C, or 700°C, to reduce the carbon dioxide to carbon (C) and adsorb the carbon onto the Na-Ni / Al2O3 powder. In some embodiments, the volume ratio of carbon dioxide to hydrogen is between 3:1 and 1:3. In some embodiments, the volume ratio of carbon dioxide to hydrogen is 1:1. In some embodiments, the time period for supplying carbon dioxide to the reactor is between 2 hours and 36 hours. In some embodiments, carbon is grafted to Ni (nickel) atoms in the Na—Ni / Al 2 O 3 powder to form a C:Na—Ni / Al 2 O 3 composite powder.

[0029] In some embodiments, forming the C:Na-Ni / Al2O3 composite powder further includes performing a sintering process to rearrange the lattice of the C:Na-Ni / Al2O3 composite powder. In some embodiments, the sintering temperature is 500°C to 800°C, for example, 550°C, 650°C, or 750°C. In some embodiments, the sintering time is 1 to 2 hours, although the present invention is not limited thereto.

[0030] The crosslinker may be formed from a low molecular weight siloxane. In some embodiments, the crosslinker may be formed from a low molecular weight halogen-containing siloxane. In some embodiments, the crosslinker may include a low carbon number chlorine-containing siloxane. For example, the crosslinker may have a structure represented by formula (1): [ka] In the formula, each R may independently be alkyl having 1 to 6 carbon atoms.

[0031] The cross-linking agent may be grafted onto the outer surface of the support by adsorption or bonding. In some embodiments, after the cross-linking agent is bonded to the C:Na—Ni / Al2O3 support, the structure represented by formula (2) is formed. [ka]

[0032] The adsorbent may be derived from a deep eutectic solvent (DES). Deep eutectic solvents are generally considered a type of ionic liquid and refer to ionic compounds in the liquid state. In some embodiments, the adsorbent is an ionic compound having a positive charge. Examples of cationic moieties that provide the positive charge include imidazole ion, pyridine ion, quaternary phosphonium ion, quaternary ammonium ion, guanidinium ion, sulfonium ion, choline ion, and morpholinium ion.

[0033] In some embodiments, the adsorbent may be, for example, hexafluorophosphate (PF6 - ), tetrafluoroborate ion (BF4 - ), tetrachloroferrate ion (FeCl4 - ) or acetate ion (OAc - In some embodiments, the adsorbent may further comprise anions with higher metal adsorption capacity, such as choline chloride and glycerol. This adsorbent can form stable chelate structures with some metal ions, providing high selectivity and ideal adsorption capacity for the detection and separation of metal ions.

[0034] In some embodiments, the adsorbent comprises 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF]), 1-ethyl-3-methylimidazolium tetrafluoroborate ([EMIM][BF]), 1-ethyl-3-methylimidazolium hexafluorophosphate ([EMIM][PF]), 1-butyl-3-methylimidazolium acetate ([BMIM][OAc]), choline chloride, glycerol, or a combination thereof. In some embodiments, the adsorbent comprises at least two of 1-butyl-3-methylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazolium tetrafluoroborate, 1-ethyl-3-methylimidazolium hexafluorophosphate, 1-butyl-3-methylimidazolium acetate, choline chloride, and glycerol.

[0035] The adsorbent may be grafted to the outer surface of the support by adsorption or bonding. In some embodiments, the adsorbent is grafted to the support by grafting the adsorbent to a cross-linking agent, with one end of the cross-linking agent connected to the support and the other end connected to the adsorbent. In some embodiments, the adsorbent is grafted to the C:Na-Ni / Al2O3 support through the chlorine end of the cross-linking agent, thus forming a complex ionic compound, as represented by the following formula (3): [ka]

[0036] For example, a chlorine-containing siloxane (crosslinker) represented by formula (1) may be reduced in an acidic environment (pH = 4-5) to have hydroxyl groups. The reduced chlorine-containing siloxane then reacts with a C:Na-Ni / Al2O3 composite powder (support) to graft the chlorine-containing siloxane to the C:Na-Ni / Al2O3 composite powder via the hydroxyl groups. Next, a deep eutectic solvent containing 1-butyl-3-methylimidazolium hexafluorophosphate and 1-ethyl-3-methylimidazolium tetrafluoroborate (adsorbent) is added in an acidic environment (pH = 4-5). 1-butyl-3-methylimidazolium hexafluorophosphate and 1-ethyl-3-methylimidazolium tetrafluoroborate react with the chlorine groups of the chlorine-containing siloxane. Therefore, 1-butyl-3-methylimidazolium hexafluorophosphate and 1-ethyl-3-methylimidazolium tetrafluoroborate are grafted to chlorine-containing siloxane, respectively.Therefore, 1-butyl-3-methylimidazolium hexafluorophosphate and 1-ethyl-3-methylimidazolium tetrafluoroborate can be grafted to carrier via crosslinker, respectively.Therefore, the composite ion compound of the present invention is prepared. Alternatively, 1-butyl-3-methylimidazolium hexafluorophosphate and 1-ethyl-3-methylimidazolium tetrafluoroborate may also each be grafted to the C:Na—Ni / Al2O3 composite powder via a chlorine-containing siloxane by reacting the 1-butyl-3-methylimidazolium hexafluorophosphate and 1-ethyl-3-methylimidazolium tetrafluoroborate with a chlorine-containing siloxane to form an intermediate before reacting the intermediate with the C:Na—Ni / Al2O3 composite powder.

[0037] In some embodiments, the composite ionic compound includes a support, a cross-linking agent grafted to the support, and two types of adsorbents, each grafted to the cross-linking agent. In some embodiments, two or more types of adsorbents are grafted to the support under different reaction conditions, and the different adsorbents may undergo different reactions, such as adsorption or depolymerization reactions. In some embodiments, the weight ratio of adsorbent to support in the composite ionic compound is 1.8 or more and 3 or less.

[0038] The composite ionic compound of the present invention can be used to recover metal ions, for example, recover metal ions from lithium-ion battery recovery solution. In some embodiments, the method for recovering metal ions may include the following steps: First, add the composite ionic compound to the lithium-ion battery recovery solution so that the composite ionic compound can adsorb metal ions, such as manganese ions, cobalt ions, nickel ions, lithium ions, or a combination thereof, in the lithium-ion battery recovery solution. Second, because the composite ionic compound has magnetic properties, the composite ionic compound with adsorbed metal ions can be attracted to a magnetic material (e.g., a magnet), thereby attaching the composite ionic compound with adsorbed metal ions to the magnetic material. Finally, the composite ionic compound with adsorbed metal ions may be separated by filtration. This significantly simplifies the separation process of the composite ionic compound.

[0039] In some embodiments, the metal ions adsorbed on the complex ion compound can be further washed away using a solvent, allowing the metal ion-removed complex ion compound to be reused. In some embodiments, each type of washed metal ion can be separated and purified by electrochemical techniques. For example, the metal ions adsorbed on the complex ion compound can be extracted by solvent extraction. In some embodiments, a volatile organic solvent (e.g., ethyl acetate and methanol) can be used to perform solvent extraction on the complex ion compound that adsorbs the metal ions to separate the metal ions from the complex ion compound and extract the metal ions into the organic solvent. The metal ions in the solvent can then be separated and purified by evaporation of the volatile solvent or other suitable methods.

[0040] In some embodiments, metal ions in an organic solvent may be separated and purified by electrolytic reduction. For example, metal ions in an organic solvent may be electrolyzed as an electrolyte. Under appropriate potential and appropriate electrolysis conditions, the metal ions are reduced to the metal, and the purified metal may be collected from the electrolysis electrodes.

[0041] In some embodiments, metal ions in an organic solvent may be separated and purified by electrochemical separation methods (potential-controlled electrolytic separation) as described below.

[0042] For example, Cu 2+ (Standard electrode potential E 0 = +0.345 volts) and Bi 3+ (E 0 If there are two or more types of metal ions in a solution and the reduction potential of one of the metal ions is close to that of the other metal ions, such as when the reduction potential of the other metal ions is close to that of the other metal ions, the two or more metal ions will be reduced and precipitated during electrolysis, making it impossible to achieve the purpose of separation.

[0043] Figure 2 shows the decomposition potentials of two different metal ions, metal ion A and metal ion B. When the cathode potential is controlled to potential b, metal ion T generates a current with a current intensity of d, and thus metal ion T is reduced. However, metal ion B generates an extremely small current intensity and is barely reduced. This allows the separation goal to be achieved while separating and measuring metal ions T and B.

[0044] In some embodiments, the reduction electrode is the cathode. Controlling the cathode potential requires constant adjustment of the applied voltage. The electrode material is a corrosion-resistant, highly reactive material. Platinum group metals are typically employed. Figure 3 is a schematic diagram showing a potential control circuit used in electrolytic separation. In Figure 3, electrode e1 is a platinum mesh cathode, electrode e2 is a platinum wire counter electrode, and electrode e3 is a reference electrode (e.g., a saturated calomel electrode). The potential of the selected electrode e1 (relative to electrode e3) can be read from potentiometer V. The electrolysis current can be read from milliammeter A. During the electrolysis process, resistor r is continuously adjusted to maintain a constant cathode potential.

[0045] In some embodiments, the multiple metal ions adsorbed by the composite ion compound may be separated by electrochemical metal-selective separation techniques. For example, in the case of a composite ion compound that adsorbs multiple metal ions, the metal ions may be dissolved using sulfuric acid or hydrochloric acid. Then, depending on the difference in redox potentials of each of the multiple metal ions, each of the multiple metals is selectively reduced in sequence by voltage control, thereby achieving the goal of metal separation. For example, the following equations show the redox potentials of nickel (Ni), manganese (Mn), cobalt (Co), and lithium (Li) for separating Ni, Mn, Co, and Li:

number

[0046] The separation of metals can be carried out by the following steps.

[0047] In some embodiments, the voltage (E 0 ) is controlled to be between -0.3V and -1.2V, and metallic Ni and Co are deposited on the electrode surface.

[0048] In some embodiments, the voltage (E 0 ) is controlled to be −1.2 V to −3 V, and metallic Mn is deposited on the electrode surface.

[0049] In some embodiments, the voltage (E 0 ) is controlled to be > -3V, and metallic Li is deposited on the electrode surface.

[0050] Therefore, different voltages (E 0 ) spacing to achieve separation of the metals.

[0051] In view of the above, the adsorbent in the composite ion compound of the present invention interacts with metal ions to form a chelate coordination, so that the adsorbent can be used for separating and extracting metal ions to further promote the recovery of metal ions. Furthermore, since the composite ion compound has magnetic properties and is easy to separate, the method for recovering metal ions of the present invention can greatly simplify the recovery process and reduce the recovery cost of metal ions. [Industrial Applicability]

[0052] The composite ion compound and the method for producing the same of the present invention can be applied to the recovery of metal ions.

[0053] It will be apparent to those skilled in the art that various modifications and variations can be made to the disclosed embodiments without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the present invention cover modifications and variations provided they come within the scope of the following claims and their equivalents. [Explanation of symbols]

[0054] S1, S2, S3: Steps

Claims

1. A carrier; a cross-linking agent adsorbed or bound to the carrier; an adsorbent adsorbed or bonded to the chlorine terminus of the crosslinker; The support is C:Na—Ni / Al ２ O ３ Composite powders include Na-Ni / Al ２ O ３ Carbon is adsorbed on the Ni atoms of the powder, The crosslinking agent contains a chlorine-containing siloxane represented by the following formula (1): 【Chemistry 1】 wherein each R is independently alkyl having 1 to 6 carbon atoms; The adsorbent is a complex ionic compound comprising at least one of 1-butyl-3-methylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazolium tetrafluoroborate, 1-ethyl-3-methylimidazolium hexafluorophosphate, or 1-butyl-3-methylimidazolium acetate.

2. 10. The complex ionic compound of claim 1, wherein the adsorbent comprises at least two of 1-butyl-3-methylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazolium tetrafluoroborate, 1-ethyl-3-methylimidazolium hexafluorophosphate, or 1-butyl-3-methylimidazolium acetate.

3. Adsorbing or binding the cross-linking agent to a support; adsorbing or bonding an adsorbent to the chlorine end of the cross-linking agent to form the complex ionic compound; The support is C:Na—Ni / Al ２ O ３ Composite powders include Na-Ni / Al ２ O ３ Carbon is adsorbed on the Ni atoms of the powder, The crosslinking agent contains a chlorine-containing siloxane represented by the following formula (1): 【Chemistry 2】 wherein each R is independently alkyl having 1 to 6 carbon atoms; A method for producing a complex ionic compound, wherein the adsorbent comprises at least one of 1-butyl-3-methylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazolium tetrafluoroborate, 1-ethyl-3-methylimidazolium hexafluorophosphate, and 1-butyl-3-methylimidazolium acetate.

4. further comprising forming the carrier; forming the carrier The Na—Ni / Al ２ O ３ placing the powder in a reactor; Carbon dioxide and hydrogen are supplied to the reactor, and the temperature in the reactor is set to 400°C to 800°C to reduce the carbon dioxide to carbon, which is then converted into the Na-Ni / Al ２ O ３ The C:Na-Ni / Al is adsorbed onto the Ni atoms in the powder. ２ O ３ forming a composite powder; The method for producing the composite ionic compound of claim 3, comprising:

5. 4. The method for producing a complex ionic compound according to claim 3, wherein the adsorbent comprises at least two of 1-butyl-3-methylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazolium tetrafluoroborate, 1-ethyl-3-methylimidazolium hexafluorophosphate, or 1-butyl-3-methylimidazolium acetate.

6. 1. Use of a complex ion compound in the recovery of metal ions, comprising: adding the composite ionic compound according to claim 1 to a recovery solution containing metal ions so that the composite ionic compound can adsorb the metal ions; separating the composite ionic compound that has adsorbed the metal ions; extracting the composite ionic compound having adsorbed the metal ions with a solvent to separate the metal ions from the composite ionic compound and extracting the metal ions into the solvent; purifying the metal ions in the solvent; Including, In the complex ionic compound, the adsorbent forms a stable chelate structure with the metal ion.

7. The use according to claim 6, wherein the recovery solution is a lithium ion battery recovery solution.

8. 7. The use of claim 6, wherein the metal ions comprise manganese ions, cobalt ions, nickel ions, lithium ions, or a combination thereof.

9. 7. The use according to claim 6, wherein the separation of the complex ionic compounds having adsorbed metal ions is carried out using a magnetic material that adsorbs the complex ionic compounds.

10. The use according to claim 6, wherein the solvent comprises ethyl acetate or methanol.

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