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JP-7855960-B2 - Metal salt extractant, composition, method for recovering metal salts, and method for producing metal salts

JP7855960B2JP 7855960 B2JP7855960 B2JP 7855960B2JP-7855960-B2

Inventors

  • 近藤 慎一
  • 高野 美優
  • 平澤 学

Assignees

  • 株式会社レゾナック

Dates

Publication Date
20260511
Application Date
20220727

Claims (7)

  1. A metal salt extractant that extracts at least one of a cuprous salt and a silver salt, and is a compound represented by the following general formula (1). (In general formula (1), R1 and R2 are each independently a hydrogen atom, an alkyl group, an aryl group, a heteroaryl group, an alkoxy group, a hydroxyl group, or a group represented by -NHR', and R' is a hydrogen atom, an alkyl group, an aryl group, a heteroaryl group, an alkoxy group, or a hydroxyl group.)
  2. The metal salt extractant according to claim 1, wherein the compound is represented by the following general formula (2). (In general formula (2), R3 and R4 are each independently a hydrogen atom, an alkyl group, an aryl group, a heteroaryl group, an alkoxy group, or a hydroxyl group.)
  3. The metal salt extractant according to claim 2, wherein in the general formula (2), R3 and R4 are each independently an n-butyl group, a tert-butyl group, or a phenyl group.
  4. A composition comprising a metal salt extractant and a non-aqueous solvent according to any one of claims 1 to 3.
  5. A method for recovering metal salts using the metal salt extractant described in any one of claims 1 to 3.
  6. A method for separating at least one of a cuprous salt and a silver salt from a metal salt-containing material and producing at least one of a cuprous salt and a silver salt, A method for producing a metal salt, comprising the steps of: preparing a mixture containing the metal salt-containing material, a metal salt extractant according to any one of claims 1 to 3, and a non-aqueous solvent; and separating the mixture into solid and liquid phases to obtain a metal salt-containing liquid.
  7. A method for separating at least one of a cuprous salt and a silver salt from a metal salt-containing material and producing at least one of a cuprous salt and a silver salt, A step of preparing a mixture comprising the metal salt-containing material, the metal salt extractant according to any one of claims 1 to 3, and a non-aqueous solvent. A method for producing a metal salt, comprising the steps of: separating the mixture into solid and liquid phases to obtain a metal salt-containing liquid; and recovering the metal salt extractant from the metal salt-containing liquid.

Description

One embodiment of the present invention relates to a metal salt extractant, a composition, a method for recovering a metal salt, and a method for producing a metal salt. The automotive industry, information and communication technology industry, and other sectors utilize large amounts of metal resources. However, concerns exist that increasing global demand for metal resources and the uneven distribution of reserves may lead to a reduction in the supply and price increases of these resources. Therefore, attempts are being made to extract and recycle metal resources from industrial waste. Recycling allows for the extraction of individual metal resources with high purity, enabling the provision of products that meet the requirements of various industrial sectors. Among metallic resources, transition metals share similar properties due to their common outermost electron configuration, making the technology for extracting a single transition metal from multiple types complex. When transition metals form metal salts rather than elemental metals, recovering the transition metal in salt form allows for the direct recycling of the recovered salt. However, the technology for sorting and recovering metal salts based on their valency is even more complex. For example, copper chloride I (CuCl), a chloride salt of monovalent copper ions, is used as a catalyst in organic chemical reactions. Recovering copper chloride I directly after the catalytic reaction can improve recycling efficiency. Silver chloride (AgCl) is also widely used as a photosensitive material in photographic development. Silver chloride can be extracted and recycled from waste liquid after development and used photographs. Furthermore, technologies to remove copper chloride I and silver chloride, which are present as impurities, are expected to improve the purity of products. There is also a need to extract and recycle copper chloride I and silver chloride from various types of industrial waste. Chemical separation is a technology used to extract metal resources from materials, and it is possible to extract metal resources with high purity using chemical reactions, electrolysis, etc. Among these methods, the method of separating metals using extractants in a solvent can precisely separate specific metals. On the other hand, one technique for recovering ions from a solvent is to capture anions in the solvent using anion receptors. The molecular structure of the anion receptor allows for selective capture of the target ion species. Non-patent documents 1 and 2 disclose anion receptors having a urea group at the 8,8'-position of a 2,2'-binaphthyl group. S. Kondo, H. Sonoda, T. Katsu, and M. Unno, Sens. Actuators B, 160, 684-690 (2011).S. Kondo, M. Nagamine, S. Karasawa, M. Ishihara, M. Unno, and Y. Yano, Tetrahedron, 67, 943-950 (2011). Figure 1 is a graph showing the results of measuring the 1H NMR of compound 2b in the presence of a metal salt in the example. The following describes one embodiment of the present invention, but the present invention is not limited by the following examples. "Metal salt extractants" A metal salt extractant according to one embodiment is a metal salt extractant that extracts at least one of a cuprous salt and a silver salt, and is characterized by being a compound represented by the following general formula (1). (In general formula (1), R1 and R2 are each independently a hydrogen atom, an alkyl group, an aryl group, a heteroaryl group, an alkoxy group, a hydroxyl group, or a group represented by -NHR', and R' is a hydrogen atom, an alkyl group, an aryl group, a heteroaryl group, an alkoxy group, or a hydroxyl group.) Hereinafter, compounds represented by general formula (1) will be collectively referred to as metal salt extractants. This metal salt extractant is capable of capturing at least one of cuprous and silver salts in a non-aqueous solvent and can be used to extract at least one of cuprous and silver salts from a non-aqueous solvent. In particular, this metal salt extractant is excellent at selectively capturing chloride ions released into a non-aqueous solvent. By capturing them together with at least one of their counterions, cuprous and silver ions, it becomes possible to extract them in the form of at least one of copper chloride (CuCl) or silver chloride (AgCl). An anion receptor having a urea group at the 8,8'-position of the 2,2'-binaphthyl group exhibits excellent anion-capturing ability due to its rigid structure resulting from the 2,2'-binaphthyl group and the presence of urea groups at both ends. This compound is represented by the following general formula (10). (In general formula (10), R is an n-butyl group, a tert-butyl group, or a phenyl group.) Unlike the compound represented by general formula (10), the compound represented by general formula (1) has a structure in which the binaphthalene skeleton is replaced with a skeleton having an aliphatic chain and a sulfur atom (S). Due to its flexible stru