Adsorbent, method for producing adsorbent, adsorption cartridge, method for removing first transition metal, and method for producing aqueous solution from which first transition metal has been removed

Abstract

The purpose of the present invention is to provide an adsorbent for removing a first transition metal, a method for producing an adsorbent, an adsorption cartridge containing an adsorbent, a method for removing a first transition metal by using an adsorption cartridge, and a method for producing an aqueous solution from which a first transition metal has been removed by using an adsorption cartridge.　An adsorbent for removing a first transition metal from an aqueous solution containing the first transition metal, said adsorbent containing activated carbon which supports a quinolinol compound or a dihydroxynaphthalene compound therein, wherein the supported amount of the quinolinol compound or the dihydroxynaphthalene compound relative to 1g of the activated carbon is 300-1,750 μmol / g.

Description

Adsorbent, method for producing adsorbent, adsorption cartridge, method for removing first transition metals, and method for producing aqueous solution from which first transition metals have been removed

[0001] The present invention relates to an adsorbent for removing first transition metals, a method for producing the adsorbent, an adsorption cartridge, a method for removing first transition metals using the adsorption cartridge, and a method for producing an aqueous solution from which first transition metals have been removed using the adsorption cartridge.

[0002] There is a demand for removing metal impurities such as copper contained in aqueous solutions, such as absorption solutions used in devices such as absorption refrigerators and electrolytic solutions for metal plating.

[0003] For example, in absorption solutions used in devices such as absorption chillers, the lithium bromide aqueous solution contained in the absorption solution is corrosive to metals, causing metal ions such as copper to leach from components of the absorption chiller, ultimately precipitating as compounds. Such metal impurities in the absorption solution can impede the flow of refrigerant, hinder operation of the device, and eventually lead to device failure. To address this issue, it is common to replace the absorption solution containing metal impurities with a new one during overhaul of the device. Furthermore, for example, in electrolytic solutions for metal plating, the presence of metal impurities introduced during various plating processes is known to adversely affect plating adhesion. To address this issue, it has been necessary to replace part or all of the electrolytic solution for metal plating.

[0004] As methods for removing metal impurities, there have been disclosed a method in which a solution is made alkaline to coagulate metals as poorly soluble compounds (Patent Document 1), and a method in which metal impurities are adsorbed and removed using a treatment agent in which a nitrogen-containing heterocyclic compound or a nitrogen-containing organic compound is supported on activated carbon (Patent Document 2).

[0005] JP 2002-205062 A JP 2020-075246 A

[0006] However, the method disclosed in Patent Document 1 sometimes removes useful metals contained in the aqueous solution, resulting in insufficient removal efficiency. Patent Document 2 also does not describe experimental results on selectively removing only specific metal species from a metal-containing aqueous solution. Furthermore, there is a demand for adsorption cartridges that can selectively remove specific metals even while an absorption chiller or other device is in operation, but such uses for the above-mentioned treatment agent are unknown, and the demand is currently not being met.

[0007] The present invention has been achieved in view of the above-mentioned circumstances, and an object of the present invention is to provide an adsorbent for removing first transition metals, a method for producing the adsorbent, an adsorption cartridge containing the adsorbent, a method for removing first transition metals using the adsorption cartridge, and a method for producing an aqueous solution from which first transition metals have been removed using the adsorption cartridge.

[0008] That is, the present invention provides an adsorbent for removing first transition metals from an aqueous solution containing the first transition metals, the adsorbent comprising activated carbon supporting a quinolinol compound or a dihydroxynaphthalene compound, wherein the amount of the quinolinol compound or the dihydroxynaphthalene compound supported per 1 g of the activated carbon is 300 to 1750 μmol / g.

[0009] In the adsorbent, the first transition metal is preferably one or more metals selected from the group consisting of copper, cobalt, nickel, iron, and zinc.

[0010] The quinolinol compounds include 2-quinolinol, 4-quinolinol, 8-quinolinol, 2-methyl-8-hydroxyquinoline, 5-fluoro-8-hydroxyquinoline, 5-chloro-8-hydroxyquinoline, 5-bromo-8-hydroxyquinoline, 5-phenyl-8-hydroxyquinoline, 8-hydroxyquinoline-5-carboxylic acid, 8-hydroxyquinoline-5-carboxylic acid methyl ester, 8-hydroxy-5-quinolyl methyl ketone, 8-hydroxy-5-quinolyl vinyl ketone, 8-hydroxyquinoline, 8-hydroxyquinoline-5-carboxylic acid methyl ester, 8-hydroxy-5-quinolyl methyl ketone, 8-hydroxy-5-quinolyl vinyl ketone, 8-hydroxyquinoline, 8-hydroxyquinoline-5-carboxylic acid methyl ester, 8-hydroxy-5-quinolyl methyl ketone, 8-hydroxy-5-quinolyl vinyl ketone, 8-hydroxyquinoline, 8-hydroxyquinoline-5-carboxylic acid methyl ester, 8-hydroxy-5-quinolyl methyl ketone, 8-hydroxyquinoline-5-carboxylic acid methyl ester, 8-hydroxy-5-quinolyl vinyl ... It is preferred that the compound contains one or more compounds selected from the group consisting of 5-quinolylphenyl ketone, 5-trifluoromethyl-8-hydroxyquinoline, 5-methoxy-8-hydroxyquinoline, 5-phenoxy-8-hydroxyquinoline, 5-trimethylsilyl-8-hydroxyquinoline, 5-cyano-8-hydroxyquinoline, 5-nitro-8-hydroxyquinoline, 5-dimethylamino-8-hydroxyquinoline, 8-hydroxyquinoline-5-sulfonic acid, and 8-hydroxyquinolinol.

[0011] The dihydroxynaphthalene compound preferably contains one or more compounds selected from the group consisting of 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, and 2,7-dihydroxynaphthalene.

[0012] The aqueous solution containing the first transition metal is preferably an absorption solution used in an absorption refrigerator, an absorption water cooler / heater, or an absorption air conditioner, or an electrolytic solution for metal plating.

[0013] The present invention also provides a method for producing an adsorbent for removing first transition metals from an aqueous solution containing the first transition metals, the method comprising a contacting step of contacting a quinolinol compound or a dihydroxynaphthalene compound with activated carbon and a solvent to obtain activated carbon supporting the quinolinol compound or the dihydroxynaphthalene compound in an amount of 300 to 1750 μmol / g per 1 g of the activated carbon.

[0014] The present invention still further provides an adsorption cartridge for removing first transition metals from an aqueous solution containing the first transition metals, the adsorption cartridge being packed with an adsorbent comprising activated carbon carrying a quinolinol compound or a dihydroxynaphthalene compound.

[0015] In the adsorption cartridge, the first transition metal is preferably one or more metals selected from the group consisting of copper, cobalt, nickel, iron, and zinc.

[0016] The present invention still further provides a method for removing first transition metals, which comprises a step of passing an aqueous solution containing the first transition metal through an adsorbent packed in an adsorption cartridge to adsorb and remove the first transition metal, wherein the adsorbent comprises activated carbon supporting a quinolinol compound or a dihydroxynaphthalene compound.

[0017] The present invention still further provides a method for producing an aqueous solution from which a first transition metal has been removed, the method comprising the step of passing an aqueous solution containing the first transition metal through an adsorbent packed in an adsorption cartridge to adsorb and remove the first transition metal, wherein the adsorbent comprises activated carbon supporting a quinolinol compound or a dihydroxynaphthalene compound.

[0018] According to the present invention, it is possible to selectively remove first transition metals from an aqueous solution containing the first transition metals.

[0019] 1 is a cross-sectional view showing the pores of activated carbon, and FIG. 2 is a schematic view (longitudinal cross-sectional view) showing an outline of an adsorption cartridge according to one embodiment of the present invention.

[0020] (Adsorbent) The adsorbent of the present invention at least contains activated carbon supporting a quinolinol compound or a dihydroxynaphthalene compound. The amount of the quinolinol compound or the dihydroxynaphthalene compound supported per gram of activated carbon is 300 to 1750 μmol / g, preferably 400 to 1650 μmol / g. In this specification, activated carbon supporting a quinolinol compound or a dihydroxynaphthalene compound may be referred to as "adsorbent (X)." That is, the adsorbent of the present invention at least contains adsorbent (X). In the adsorbent of the present invention, the amount of the quinolinol compound or the dihydroxynaphthalene compound supported by adsorbent (X) per gram of activated carbon is 300 to 1750 μmol / g.

[0021] In the adsorbent (X), a quinolinol compound or a dihydroxynaphthalene compound is fixed to the activated carbon, which is the supported material. Here, "fixed" essentially means an embodiment in which the quinolinol compound or the dihydroxynaphthalene compound is considered to be present on the activated carbon due to, for example, the mutual affinity between the activated carbon and the quinolinol compound or the dihydroxynaphthalene compound. Therefore, in this specification, the terms "supported" and "fixed" include at least an embodiment in which the quinolinol compound or the dihydroxynaphthalene compound is present near the outer surface and / or pores of the activated carbon, and do not refer only to an embodiment in which the quinolinol compound or the dihydroxynaphthalene compound is directly attached to the outer surface and / or pores of the activated carbon.

[0022] The quinolinol compound or dihydroxynaphthalene compound may be present on at least a portion of the outer surface and / or pores of the activated carbon, but may not be present throughout the outer surface and pores of the activated carbon. In particular, it is preferable that the quinolinol compound or dihydroxynaphthalene compound is present throughout the outer surface and pores of the activated carbon, i.e., the quinolinol compound or dihydroxynaphthalene compound is supported on the activated carbon without any uneven distribution.

[0023] Examples of the quinolinol compound include quinolinols such as 2-quinolinol, 4-quinolinol, and 8-quinolinol; alkylquinolinols such as 2-methyl-8-hydroxyquinoline; halogenated quinolinols such as 5-fluoro-8-hydroxyquinoline, 5-chloro-8-hydroxyquinoline, and 5-bromo-8-hydroxyquinoline; arylquinolinols such as 5-phenyl-8-hydroxyquinoline; carboxy-substituted quinolinols such as 8-hydroxyquinoline-5-carboxylic acid; ester-substituted quinolinols such as 8-hydroxyquinoline-5-carboxylic acid methyl ester; 8-hydroxy-5-quinolyl methyl ketone, 8-hydroxy-5-quinolyl vinyl ketone, and 8-hydroxy-5-quinolyl phenyl ketone. Examples of suitable quinolinol compounds include alkyl-, alkenyl-, or arylcarbonyl-substituted quinolinols such as quinolinol, fluoroalkylquinolinols such as 5-trifluoromethyl-8-hydroxyquinoline, alkoxy- or aryloxyquinolinols such as 5-methoxy-8-hydroxyquinoline and 5-phenoxy-8-hydroxyquinoline, trialkylsilylquinolinols such as 5-trimethylsilyl-8-hydroxyquinoline, cyanoquinolinols such as 5-cyano-8-hydroxyquinoline, nitroquinolinols such as 5-nitro-8-hydroxyquinoline, dialkylaminoquinolinols such as 5-dimethylamino-8-hydroxyquinoline, and sulfonate-substituted quinolinols such as 8-hydroxyquinoline-5-sulfonic acid. Among these, the quinolinol compound is preferably a quinolinol or an alkylquinolinol, more preferably a quinolinol, and particularly preferably 8-quinolinol. The quinolinol compounds may be used alone or in combination of two or more.

[0024] Examples of the dihydroxynaphthalene compound include 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, and 2,7-dihydroxynaphthalene. Of these, 2,3-dihydroxynaphthalene is preferred as the dihydroxynaphthalene compound. The dihydroxynaphthalene compounds may be used alone or in combination of two or more.

[0025] The activated carbon in the adsorbent (X) is a porous body having pores (particularly micropores). The pores include micropores with a diameter of 2 nm or less, mesopores with a diameter of more than 2 nm and less than 50 nm, and macropores with a diameter of more than 50 nm, and the activated carbon may have any of these pores. In this specification, the terms micropore, mesopore, and macropore refer to those classified according to the International Union of Pure and Applied Chemistry (IUPAC). The pore diameter can be measured by mercury intrusion porosimetry for the macropores, and by gas adsorption for the mesopores and micropores. The pore diameter of the activated carbon is, for example, 0.01 nm to 500 nm, preferably 0.1 nm to 250 nm, and more preferably 0.1 nm to 50 nm.

[0026] FIG. 1 is a cross-sectional view schematically illustrating the pores of activated carbon. Activated carbon 10 has at least one of micropores 12, mesopores 14, and macropores 16. In the adsorbent of the present invention, the quinolinol compound or dihydroxynaphthalene compound may be present on the outer surface of activated carbon 10 and / or in at least a portion of the pores. When the quinolinol compound or dihydroxynaphthalene compound is present in the pores of activated carbon 10, it may be present in any one of micropores 12, mesopores 14, or macropores 16 of activated carbon 10. Preferably, the quinolinol compound or dihydroxynaphthalene compound is present in both micropores 12 and mesopores 14, both mesopores 14 and macropores 16, or both micropores 12 and macropores 16. More preferably, the quinolinol compound or dihydroxynaphthalene compound is present in all of micropores 12, mesopores 14, and macropores 16.

[0027] The shape of the activated carbon is not particularly limited, and may be, for example, powder, granules, fibers, or a columnar shape (e.g., cylindrical), etc. Since the adsorbent (X) contains the activated carbon as a base material of the adsorbent, the shape of the adsorbent (X) may also be powder, granules, fibers, or a columnar shape (e.g., cylindrical), etc.

[0028] The type of activated carbon is not particularly limited, and may be, for example, chemically activated or gas-activated activated carbon. The raw material for the activated carbon is not particularly limited, and examples thereof include charcoal, coconut shell charcoal, coal (e.g., lignite, brown coal, bituminous coal, anthracite, etc.), sawdust, wood chips, grass peat (e.g., beet, etc.), coal pitch, and petroleum pitch. When the activated carbon is in the form of a fiber, the raw material may be rayon, acrylonitrile, or phenol.

[0029] The activated carbon may be used alone or in combination with two or more types (for example, activated carbons having different pores, activated carbons having different shapes, or activated carbons of different types and made from different raw materials).

[0030] The adsorbent of the present invention may consist solely of the adsorbent (X), or may contain other adsorbents (e.g., other activated carbon, inorganic adsorbents, etc.) in addition to the adsorbent (X). Examples of such other activated carbon include unsupported activated carbon, such as the activated carbon exemplified and described as the activated carbon in the adsorbent (X). Examples of such inorganic adsorbents include silica gel, molecular sieves, hydroxyapatite, and zeolites.

[0031] The content of the adsorbent (X) relative to 100% by weight of the total amount of the adsorbent of the present invention is not particularly limited, but from the viewpoint of excellent performance in removing first transition metals, it is, for example, 50% by weight or more, preferably 70% by weight or more, more preferably 80% by weight or more, and particularly preferably 90% by weight or more. The upper limit is not particularly limited, but is, for example, 100% by weight.

[0032] The adsorbent of the present invention is an adsorbent for removing first transition metals from an aqueous solution containing the first transition metals. Furthermore, by using the adsorbent of the present invention, the first transition metals contained in the aqueous solution can be selectively removed. Without being bound by any particular theory, the reason why the adsorbent of the present invention can selectively remove the first transition metals is thought to be that the quinolinol compound or the dihydroxynaphthalene compound in the adsorbent (X) contained in the adsorbent of the present invention forms a strong complex bond with the first transition metal, resulting in the formation of a metal complex while the quinolinol compound or the dihydroxynaphthalene compound remains supported on the activated carbon surface. In this specification, "removing first transition metals" means that by passing an aqueous solution containing a first transition metal through the adsorbent of the present invention, the concentration of the first transition metal in the aqueous solution after passing through the adsorbent is lower than the concentration of the first transition metal in the aqueous solution before passing through the adsorbent.

[0033] Examples of the first transition metals include scandium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, and zinc. Among the first transition metals, iron, cobalt, nickel, copper, or zinc is preferred, with iron or copper being more preferred, due to their superior removal performance. The chemical species of the first transition metal is not particularly limited, and may be present in the aqueous solution in the form of metal ions, colloids, or complex oxides, for example. Among these, the metal ions are preferred due to their superior removal performance.

[0034] The aqueous solution may contain only one type of the first transition metal, or two or more types (for example, metals of different metal types or metals of different chemical species).

[0035] The aqueous solution containing the first transition metal may further contain a metal other than the first transition metal (hereinafter referred to as metal (B)). Examples of metal (B) include lithium, molybdenum, and tungsten. Even when the aqueous solution containing the first transition metal contains metal (B), the first transition metal can be selectively removed by using the adsorbent of the present invention.

[0036] When the aqueous solution containing the first transition metal contains the metal (B), the chemical species of the metal (B) is not particularly limited, and may be, for example, present in the aqueous solution in the form of a metal ion, a colloid, or a composite oxide.

[0037] When the aqueous solution containing the first transition metal contains the metal (B), the aqueous solution may contain only one type of the metal (B), or may contain two or more types (for example, metals of different metal species or metals of different chemical species) of the metal (B).

[0038] When the aqueous solution containing the first transition metal contains the metal (B), the combination of the first transition metal and the metal (B) is not particularly limited and can be any combination. Among them, from the viewpoint of more excellent removal performance, a combination in which the first transition metal is copper and the metal (B) is one or more metals selected from the group consisting of lithium, molybdenum, and tungsten is preferred.

[0039] The pH of the aqueous solution containing the first transition metal is not particularly limited, but is preferably in the range of 1.5 to 14, and more preferably in the range of 2 to 14.

[0040] The concentration of the first transition metal in the aqueous solution containing the first transition metal is not particularly limited, but is, for example, 0.1 to 1000 ppm, and preferably 1 to 500 ppm. The concentration of the first transition metal in the aqueous solution containing the first transition metal can be measured by a general measurement method, such as titration or ICP emission spectroscopy.

[0041] When the aqueous solution containing the first transition metal contains the metal (B), the total concentration of the metal (B) in the aqueous solution containing the first transition metal is not particularly limited, but is, for example, 0.05 to 500,000 ppm, preferably 0.1 to 500,000 ppm. In particular, when lithium is contained as the metal (B), the concentration of lithium in the aqueous solution containing the first transition metal is not particularly limited, but is, for example, 0.05 to 500,000 ppm, preferably 0.1 to 500,000 ppm, and more preferably 1 to 500,000 ppm. Furthermore, when molybdenum and / or tungsten is contained as the metal (B), the concentration of molybdenum and / or tungsten in the aqueous solution containing the first transition metal is not particularly limited, but is, for example, 0.05 to 2,000 ppm, preferably 0.1 to 1,500 ppm, and more preferably 1 to 1,000 ppm. The concentration of the metal (B) in the aqueous solution containing the first transition metal can be measured by a general measurement method, such as titration or ICP emission spectrometry.

[0042] The aqueous solution containing the first transition metal may be an absorption solution used in an absorption chiller, an absorption water cooler / heater, or an absorption air conditioner (hereinafter sometimes referred to as a chiller, etc.), or an electrolyte solution for metal plating. Here, the absorption solution used in a chiller, etc. generally refers to an absorption solution for recovering evaporated water in a circulation system in which water is used as a refrigerant for heat exchange.

[0043] The absorption solution may generally contain, as a main component, one or more compounds selected from the group consisting of lithium bromide, lithium iodide, and lithium chloride. Other components that may be contained in the absorption solution include, for example, corrosion inhibitors such as lithium molybdate, lithium tungstate, lithium nitrate, and lithium nitrite; surfactants; and alkalinity regulators. In this specification, the absorption solution contains the first transition metals as metals eluted from components of an absorption chiller or the like. By using the adsorbent of the present invention, first transition metals such as copper can be selectively removed even when the absorption solution contains metal (B) such as lithium or molybdenum.

[0044] When removing first transition metals from the absorption solution using the adsorbent of the present invention, the method is not particularly limited. For example, the absorption solution is extracted from a circulation line of a refrigerator or the like, the adsorbent of the present invention is added to the extracted absorption solution, and the resulting solution is stirred, whereby the first transition metals in the absorption solution can be adsorbed onto the adsorbent of the present invention and removed.

[0045] Examples of the metal plating electrolyte include a noble metal plating electrolyte, a copper plating electrolyte, etc. Examples of the noble metal in the noble metal plating electrolyte include gold, silver, platinum, palladium, rhodium, iridium, ruthenium, osmium, etc.

[0046] (Method for Producing Adsorbent) The method for producing an adsorbent of the present invention includes at least a contacting step of contacting a quinolinol compound or a dihydroxynaphthalene compound with activated carbon and a solvent to obtain activated carbon supporting the quinolinol compound or the dihydroxynaphthalene compound in an amount of 300 to 1,750 μmol / g (preferably 400 to 1,650 μmol / g) per 1 g of the activated carbon.

[0047] In the contacting step, a quinolinol compound or a dihydroxynaphthalene compound is contacted with a solvent and activated carbon. By contacting the quinolinol compound or the dihydroxynaphthalene compound with the activated carbon in a solvent, the quinolinol compound or the dihydroxynaphthalene compound can be supported on the activated carbon in an amount of 300 to 1,750 μmol / g (preferably 400 to 1,650 μmol / g) per 1 g of the activated carbon.

[0048] In the contacting step, the method for contacting the quinolinol compound or dihydroxynaphthalene compound with the solvent and activated carbon is not particularly limited, and a commonly used method can be used. A specific contacting method, for example, involves mixing the quinolinol compound or dihydroxynaphthalene compound with the solvent and stirring the mixture to prepare a solution of the quinolinol compound or dihydroxynaphthalene compound. The solution is then placed in a container filled with activated carbon, whereby the quinolinol compound or dihydroxynaphthalene compound can be contacted with the activated carbon, thereby obtaining activated carbon carrying the quinolinol compound or dihydroxynaphthalene compound.

[0049] The solvent is not particularly limited, but examples thereof include water; ethers such as tetrahydrofuran and dioxane; alcohols such as methanol, ethanol, isopropyl alcohol, n-propanol, and ethylene glycol; ketones such as acetone and methyl ethyl ketone; carboxylic acids such as acetic acid; carboxylic acid esters such as ethyl acetate; amides such as dimethylformamide; nitriles such as acetonitrile; halogenated hydrocarbons such as chloroform and ethylene dichloride; and sulfoxides such as dimethyl sulfoxide. Among these, the solvent is preferably water, ethers, alcohols, ketones, carboxylic acid esters, nitriles, or sulfoxides, more preferably water, tetrahydrofuran, dioxane, methanol, acetone, ethyl acetate, acetonitrile, or dimethyl sulfoxide, and even more preferably water, tetrahydrofuran, dioxane, methanol, acetone, or ethyl acetate. The solvents may be used alone or in combination of two or more.

[0050] The contact temperature in the contacting step is not particularly limited, but is, for example, 0° C. to 100° C., preferably room temperature (25° C.) to 65° C. The contact time in the contacting step is not particularly limited, but is, for example, 1 minute to 24 hours, preferably 10 minutes to 16 hours.

[0051] The method for producing an adsorbent of the present invention may further include a drying step of drying the activated carbon obtained after the contacting step.

[0052] In the drying step, the activated carbon carrying the quinolinol compound or the dihydroxynaphthalene compound obtained in the contacting step is dried, and excess solvent and the like adhering to the activated carbon obtained in the contacting step can be vaporized and removed by the drying step.

[0053] The drying method in the drying step is not particularly limited, but may be, for example, a heat treatment in which the activated carbon is heated in the range of 40°C to 200°C to evaporate the solvent, or a reduced pressure treatment in which the activated carbon is placed under reduced pressure or vacuum to evaporate the solvent. Furthermore, the heat treatment and the reduced pressure treatment may be combined as necessary.

[0054] (Adsorption Cartridge) The adsorption cartridge of the present invention is filled with an adsorbent including activated carbon supporting a quinolinol compound or a dihydroxynaphthalene compound. In this specification, the adsorbent filled in the adsorption cartridge of the present invention may be referred to as "adsorbent (Y)." That is, the adsorption cartridge of the present invention includes at least a cartridge and adsorbent (Y). The adsorbent (Y) includes at least activated carbon supporting a quinolinol compound or a dihydroxynaphthalene compound, i.e., the adsorbent (X).

[0055] In the adsorption cartridge of the present invention, the amount of the quinolinol compound or the dihydroxynaphthalene compound supported by the adsorbent (X) contained in the adsorbent (Y) per 1 g of activated carbon is not particularly limited, but from the viewpoint of excellent performance in removing first transition metals, it is preferably 300 to 1750 μmol / g, more preferably 400 to 1650 μmol / g.

[0056] The preferred embodiments of the adsorbent (Y) are the same as those of the adsorbent of the present invention described above. Furthermore, the adsorbent (Y) is preferably the adsorbent of the present invention.

[0057] In the adsorption cartridge of the present invention, the adsorbent (Y) may be filled directly into the cartridge, or the adsorbent (Y) may be pressure-molded into a molded body, and the molded body may then be filled into the cartridge. When the adsorbent (Y) is pressure-molded into a molded body, a binder may be mixed with the adsorbent (Y) for molding, or the adsorbent (Y) may be covered with a packaging material to maintain its shape.

[0058] Examples of the binder include fibers such as pulp, acrylic fiber, cellulose fiber, aramid fiber, nylon fiber, polyethylene fiber, polypropylene fiber, and polyacrylonitrile fiber. Examples of the packaging material include porous substrates such as nonwoven fabric, mesh cloth, and porous film.

[0059] The adsorption cartridge of the present invention may contain, in addition to the adsorbent (Y), known or commonly used nonwoven fabric filters, hollow fiber membranes, ion exchange resins, additives, and the like.

[0060] The material of the cartridge can be selected appropriately depending on the application and environment of use, and is not particularly limited, but examples include metals such as stainless steel; plastics; resins such as acrylic resins and polycarbonate resins; and glass.

[0061] The shape and size of the cartridge are not particularly limited, and cartridges of known or commonly used shapes and sizes can be appropriately selected depending on the application and environment of use.

[0062] In the adsorption cartridge of the present invention, the method for filling the adsorbent (Y) is not particularly limited, and the adsorbent can be filled by a known method.

[0063] One embodiment of the adsorption cartridge of the present invention will be described below with reference to FIG. 2, but the present invention is not limited to this and various modifications are possible within the scope of the gist of the invention.

[0064] FIG. 2 is a schematic diagram (longitudinal cross-sectional view) showing an outline of an adsorption cartridge according to one embodiment of the present invention, and arrows indicate the flow of water.

[0065] The adsorption cartridge 1 comprises a substantially cylindrical housing 2 having a hollow interior, a head 3 attached to one open end of the housing, and a substantially cylindrical filter element 4 housed within the housing. The outer diameter of the filter element is configured to be smaller than the inner diameter of the housing. The filter element 4 comprises a coaxial outer cylinder 42 and inner cylinder 43, and the space between the outer cylinder 42 and inner cylinder 43 is filled with an adsorbent 41 containing an adsorbent (X). The outer cylinder 42 has one or more water passage holes (not shown) through which the aqueous solution from which first transition metals have been removed by the adsorbent (X) contained in the adsorbent 41 is discharged to the outside of the filter element 4. The filter element 4 has a substantially circular cavity 44 in its center in a plan view. The cavity 44 is coaxial with and has a substantially equal diameter to the inner cylinder 43. The head 3 includes a water inlet 31, a water outlet pipe 32, a water outlet 33 connected to one end of the water outlet pipe, a support member 34 connected to the other end of the water outlet pipe, and a plate 35 connected to the support member 34. An annular protrusion 36 coaxial with the water outlet pipe 32 is formed on the water outlet 33 side of the water outlet pipe 32. The water outlet pipe 32 of the head 3 is inserted into a hollow portion 44 of the filter member 4, and one end of an inner tube 43 of the filter member 4 is detachably fitted onto the annular protrusion 36. The other end of the filter member 4 is supported by the support member 34. This secures the filter member 4 to the head 3. The head 3 is attached so as to close the open end of the housing 2. A sealant (not shown), such as an O-ring, may be provided between the housing 2 and the head 3.

[0066] To fill the adsorbent in the adsorption cartridge 1, for example, the adsorbent is filled into the space between the outer tube 42 and the inner tube 43 of the filter member 4 by a known method, and then the filter member 4 and the head 3 are fixed so that the water outlet pipe 32 is inserted into the hollow portion 44, and the fixed filter member 4 and head 3 are housed inside the hollow interior of the housing 2, and the head 3 and the housing 2 are attached.

[0067] In the adsorption cartridge 1, an aqueous solution containing first transition metals flows through the water inlet 31 into the filter element 4 attached inside the housing 2 and passes through the adsorbent 41 filled in the space between the outer tube 42 and inner tube 43 of the filter element 4. Here, the adsorbent (X) contained in the adsorbent 41 selectively removes the first transition metals from the aqueous solution containing the first transition metals. The aqueous solution that has flowed through the adsorbent 41 inside the filter element 4 flows through the water passage hole in the outer tube 42, into the space formed between the housing 2 and the outer tube 42 of the filter element 4, passes through the plate 35 and the support member 34, flows into the outlet pipe 32, and is discharged to the outside of the adsorption cartridge 1 through the water outlet 33. In this way, an aqueous solution from which first transition metals have been selectively removed can be obtained using the adsorption cartridge of the present invention.

[0068] When the adsorption cartridge of the present invention is used to remove first transition metals from an absorption solution in a refrigerator or the like, for example, a bypass can be provided in the circulation line of the absorption solution of the refrigerator or the like, the bypass can be connected to the adsorption cartridge, and the adsorption cartridge can be incorporated into the circulation line, whereby the first transition metals in the absorption solution can be adsorbed onto the adsorbent (X) in the adsorption cartridge and removed.

[0069] (Method for Removing First Transition Metals) The method for removing first transition metals of the present invention includes a step of passing an aqueous solution containing a first transition metal through an adsorbent filled in an adsorption cartridge, thereby adsorbing and removing the first transition metal onto the adsorbent. By passing the aqueous solution containing the first transition metal through the adsorption cartridge of the present invention, the first transition metal can be adsorbed onto the adsorbent (X) contained in the adsorbent (Y), thereby removing the first transition metal from the aqueous solution containing the first transition metal. This method makes it possible to produce an aqueous solution from which the first transition metal has been removed.

[0070] When an aqueous solution containing the first transition metal is passed through the adsorption cartridge (specifically, the adsorbent (Y) filled in the adsorption cartridge), the quinolinol compound in the adsorbent (X) contained in the adsorbent (Y) forms a strong complex bond with the first transition metal, and a metal complex is thought to be formed while the quinolinol compound remains supported on the activated carbon surface. As a result, the first transition metal can be selectively adsorbed onto the adsorbent (X) and removed from the aqueous solution, thereby obtaining an aqueous solution from which the first transition metal has been removed. In this specification, the term "first transition metal removed" means that the concentration of the first transition metal in the aqueous solution after passing through the adsorbent is lower than the concentration of the first transition metal in the aqueous solution before passing through the adsorbent.

[0071] The conditions for passing the aqueous solution containing the first transition metal (the aqueous solution before passing through the adsorbent) through the adsorption cartridge of the present invention are not particularly limited and can be appropriately adjusted depending on the purpose, the amount or type of the aqueous solution used, etc. Examples of the conditions include a flow rate of 0.1 to 10,000 mL / min, a space velocity SV of 0.01 to 1,000 hr, －１ The liquid passing time may be 1 minute to 48 hours, and the temperature may be 5 to 90°C.

[0072] Hereinafter, one embodiment of the present invention will be described in more detail based on examples.

[0073] In the following Production Examples and Working Examples, "supported compound" refers to the quinolinol compound or dihydroxynaphthalene compound supported by the activated carbon contained in each adsorbent, and "supported amount" refers to the amount of quinolinol compound or dihydroxynaphthalene compound supported per gram of activated carbon contained in each adsorbent.

[0074] Production Example 1: Production of Adsorbent A 3.63 g of 8-quinolinol (Tokyo Chemical Industry Co., Ltd.) and 80 g of methanol (Fujifilm Wako Pure Chemical Industries, Ltd.) were placed in a beaker and stirred for approximately 30 minutes at room temperature (approximately 25°C) and atmospheric pressure to obtain a treatment solution in which 8-quinolinol was dissolved in methanol. 50 g of thoroughly dried activated carbon (Kuraray Co., Ltd., trade name "Kuraray Coal GW40 / 20") was added thereto and allowed to stand for 10 minutes. This activated carbon was then dried for 2 hours at 40°C in a rotary evaporator (AS ONE Corporation, model [NA-2VGS]). Through the above steps, Adsorbent A (amount of quinolinol compound supported per 1 g of activated carbon: 500 μmol / g) was obtained.

[0075] Production Example 2: Production of Adsorbent B 363 g of 8-quinolinol (Tokyo Chemical Industry Co., Ltd.) and 8 kg of methanol (Fujifilm Wako Pure Chemical Industries, Ltd.) were charged into a beaker and stirred at room temperature (approximately 25°C) and atmospheric pressure for approximately 30 minutes to obtain a treated solution in which 8-quinolinol was dissolved in methanol. 5 kg of thoroughly dried activated carbon (Kuraray Co., Ltd., trade name "Kuraray Coal GW40 / 20") was added thereto and allowed to stand for 10 minutes. This activated carbon was then dried at 70°C for 8 hours in a rotary evaporator (Tokyo Rikakikai Co., Ltd., model N-21B). Through the above steps, Adsorbent B (amount of quinolinol compound supported per gram of activated carbon: 500 μmol / g) was obtained.

[0076] Production Examples 3 to 6: Production of Adsorbents C to F Adsorbents C to F were obtained in the same manner as in Production Example 1, except that the amount of quinolinol compound supported per 1 g of activated carbon was adjusted to the amount shown in Table 1.

[0077] Production Example 7: Production of Adsorbent G 4 g of 2,3-dihydroxynaphthalene (Tokyo Chemical Industry Co., Ltd.) and 80 g of methanol (Fujifilm Wako Pure Chemical Industries, Ltd.) were placed in a beaker and stirred for approximately 30 minutes at room temperature (approximately 25°C) and atmospheric pressure to obtain a treatment solution in which 2,3-dihydroxynaphthalene was dissolved in methanol. 50 g of thoroughly dried activated carbon (Kuraray Co., Ltd., trade name "Kuraray Coal GW40 / 20") was added thereto and allowed to stand for 10 minutes. The activated carbon was then dried for 2 hours at 40°C in a rotary evaporator (AS ONE Corporation, model NA-2VGS). Through the above steps, Adsorbent G (amount of dihydroxynaphthalene compound supported per 1 g of activated carbon: 500 μmol / g) was obtained.

[0078] Production Examples 8 to 11: Production of Adsorbents H to K Adsorbents H to K were obtained in the same manner as in Production Example 7, except that the amount of dihydroxynaphthalene compound supported per 1 g of activated carbon was adjusted to the amount shown in Table 1.

[0079] (Elution test of supported compounds) 1 g each of adsorbent A and adsorbents C to K was added to 10 g of ultrapure water purified using a water purification system (manufactured by Organo Corporation, product name "Purelite PRO-0100"), and the mixture was shaken at 200 rpm for 1 hour using a shaker. Thereafter, the supernatant was filtered through a 0.45 μm filter, and the absorbance at a wavelength of 280 nm was measured. A ratio beam spectrophotometer U-1800 manufactured by Hitachi, Ltd. was used to measure the absorbance. The results are shown in Table 1.

[0080] The results of the elution test of the supported compound are shown in Table 1. Note that a higher absorbance (dimensionless) value indicates a higher concentration of the quinolinol compound or dihydroxynaphthalene compound, while a lower absorbance value indicates a lower concentration of the quinolinol compound or dihydroxynaphthalene compound.

[0081]

[0082] As shown in Table 1, the absorbance values ​​for adsorbents A and C to E obtained in Production Examples 1 and 3 to 5 were all "0." This indicates that 8-quinolinol supported on the activated carbon in each adsorbent was not eluted into the aqueous solution. Similarly, the absorbance values ​​for adsorbents G to J obtained in Production Examples 7 to 10 were all "0," indicating that 2,3-dihydroxynaphthalene supported on the activated carbon in each adsorbent was not eluted into the aqueous solution. On the other hand, adsorbent F obtained in Production Example 6 had a supported amount of 8-quinolinol (supported compound) of 2000 μmol / g, and 8-quinolinol was detected in the aqueous solution as a result of absorbance measurement. Similarly, adsorbent K obtained in Production Example 11 had a supported amount of 2,3-dihydroxynaphthalene (supported compound) of 2000 μmol / g, and 2,3-dihydroxynaphthalene was detected in the aqueous solution as a result of absorbance measurement. These results show that when the amount of quinolinol compound or dihydroxynaphthalene compound supported is 2000 μmol / g, the quinolinol compound or dihydroxynaphthalene compound that cannot be supported by the activated carbon is eluted into the aqueous solution.

[0083] (Copper Adsorption Test of Adsorbents) Examples 1-3, Comparative Examples 1-2 63.5 mg of copper(II) chloride was added to 30 g of ultrapure water purified using a water purification system (manufactured by Organo Corporation, product name "Purelite PRO-0100"), and the mixture was stirred for approximately 30 minutes using a stirrer (manufactured by AS ONE Corporation, product name "Hot Stirrer REXIM RSH-1AN") at room temperature (approximately 25°C) and atmospheric pressure. 0.3 g of each of the adsorbents shown in Table 2 was added, and the mixture was shaken at 200 rpm using a shaker for 1 hour. Five mL of the supernatant was then recovered. 5 mL of the recovered supernatant was used as a sample, and 10 mL of 35% hydrochloric acid was added to the sample. The solution was then filtered, and 10 mL of the filtrate was diluted to 50 mL with ultrapure water purified using a water purification system (Organo Corporation, product name "Purelite PRO-0100"), and the copper concentration in the solution was measured by ICP optical emission spectrometry. An ICP optical emission spectrometry system (Horiba Ltd., model "ULTIMA2") was used for the measurement.

[0084] The results of the copper adsorption test are shown in Table 2. In Table 2, "activated carbon" refers to unloaded activated carbon.

[0085]

[0086] As shown in Table 2, in Examples 1 to 3 using the adsorbent of the present invention, the amount of copper adsorbed was greater than in Comparative Examples 1 and 2, demonstrating superior efficiency in removing copper contained in the solution.

[0087] (Iron Adsorption Test of Adsorbents) Examples 4-6, Comparative Examples 3-4 106.8 mg of iron(II) chloride tetrahydrate was added to 30 g of ultrapure water purified using a water purification system (Organo Corporation, product name "Purelite PRO-0100"), and the mixture was stirred for approximately 30 minutes using a stirrer (AS ONE Corporation, product name "Hot Stirrer REXIM RSH-1AN") at room temperature (approximately 25°C) and atmospheric pressure. 0.3 g of each of the adsorbents listed in Table 3 was added, and the mixture was shaken at 200 rpm for 1 hour using a shaker. Five mL of the supernatant was then recovered. 5 mL of the recovered supernatant was used as a sample, and 10 mL of 35% hydrochloric acid was added to the sample. The solution was then filtered, and 10 mL of the filtrate was diluted to 50 mL with ultrapure water purified using a water purification system (Organo Corporation, product name "Purelite PRO-0100"), and the iron concentration in the solution was measured by ICP optical emission spectrometry. An ICP optical emission spectrometer (Horiba Ltd., model "ULTIMA2") was used for the measurement.

[0088] The results of the iron adsorption test are shown in Table 3. In Table 3, "activated carbon" refers to unloaded activated carbon.

[0089]

[0090] As shown in Table 3, in Examples 4 to 6, in which the adsorbent of the present invention was used, the amount of iron adsorbed was greater than in Comparative Examples 3 and 4, demonstrating superior efficiency in removing iron contained in the solution.

[0091] (Copper Adsorption Test of Adsorption Cartridge) Example 7 108.8 mg of copper(II) chloride was added to 490 g of ultrapure water purified using a water purification system (Organo Corporation, product name "Purelite PRO-0100"), and the mixture was stirred for approximately 30 minutes using a stirrer (AS ONE Corporation, product name "Hot Stirrer REXIM RSH-1AN") at room temperature (approximately 25°C) and atmospheric pressure. 10 g of 28% aqueous ammonia was added thereto, and the mixture was stirred for an additional 30 minutes to prepare a test solution. 1.3 g of Adsorbent B prepared in Production Example 2 was filled into a 2.5 mL adsorption cartridge, and the test solution was circulated at a rate of 10 mL / min for 20 hours to conduct a copper ion adsorption test. The supernatant after the test was filtered through a 0.45 μm filter, and the absorbance at a wavelength of 600 nm was measured to determine the absorbance. The absorbance was measured using a ratio beam spectrophotometer U-1800 manufactured by Hitachi, Ltd.

[0092] Example 8 A test solution was prepared in the same manner as in Example 7. A 2.5 mL adsorption cartridge was filled with 1.3 g of adsorbent B prepared in Production Example 2, and the test solution was passed through at a rate of 0.25 mL / min for 10 hours, and the adsorption test was carried out until copper ions were detected from the outlet side. After the test, the supernatant was filtered through a 0.45 μm filter, and the absorbance was measured at a wavelength of 600 nm to determine the absorbance. A ratio beam spectrophotometer U-1800 manufactured by Hitachi, Ltd. was used to measure the absorbance.

[0093] Example 9: 50 g of copper(II) bromide was added to 30 L of ultrapure water purified using a water purification system (Organo Corporation, trade name "Purelite PRO-0100") and stirred for approximately 30 minutes at room temperature (approximately 25°C) and atmospheric pressure. A 1 L adsorption cartridge was filled with 500 g of adsorbent B prepared in Production Example 2, and the test solution was circulated at a rate of 3 L / min for 5 hours to conduct a copper ion adsorption test. The supernatant after the test was filtered through a 0.45 μm filter, and 1 mL of 28% aqueous ammonia was added to 10 mL of the test solution. The absorbance was measured at a wavelength of 600 nm to determine the absorbance. A ratio beam spectrophotometer U-1800 manufactured by Hitachi, Ltd. was used to measure the absorbance.

[0094] Comparative Example 5 A test solution was prepared in the same manner as in Example 7. A 2.5 mL adsorption cartridge was filled with 1.3 g of activated carbon (manufactured by Kuraray Co., Ltd., product name "Kuraray Coal GW40 / 20"), and the test solution was circulated at a rate of 3000 mL / min for 20 hours to conduct a copper ion adsorption test. The supernatant after the test was filtered through a 0.45 μm filter, and the absorbance was measured at a wavelength of 600 nm to determine the absorbance. A ratio beam spectrophotometer U-1800 manufactured by Hitachi, Ltd. was used to measure the absorbance.

[0095] The results of the copper adsorption tests conducted in Examples 7 to 9 and Comparative Example 5 are shown in Table 4. In Table 4, "activated carbon" refers to unloaded activated carbon. A higher liquid absorbance (dimensionless) value indicates a higher copper ion concentration. Conversely, a lower liquid absorbance value indicates a lower copper ion concentration.

[0096]

[0097] As shown in Table 4, the adsorption cartridges of the present invention (Examples 7 to 9) filled with adsorbent B showed higher adsorption capacity for copper ions than the adsorption cartridge filled with unsupported activated carbon (Comparative Example 5). Furthermore, it was found that the adsorption cartridges of the present invention exhibited excellent adsorption capacity regardless of the size of the adsorption cartridge or the flow rate of the liquid.

[0098] (Iron Adsorption Test of Adsorption Cartridge) Example 10: 157 mg of iron(II) chloride tetrahydrate was added to 300 g of ultrapure water purified using a water purification system (Organo Corporation, product name "Purelite PRO-0100"), and the mixture was stirred for approximately 30 minutes using a stirrer (AS ONE Corporation, product name "Hot Stirrer REXIM RSH-1AN") at room temperature (approximately 25°C) and atmospheric pressure to prepare a test solution. A 2.5 mL adsorption cartridge was filled with 1.5 g of the adsorbent G prepared in Production Example 7, and the test solution was circulated at a rate of 0.25 mL / min for 19 hours. The iron adsorption test was performed until iron ions were detected from the adsorption cartridge outlet. The supernatant after the test was filtered through a 0.45 μm filter, and 5 mg of ascorbic acid and 5 mg of 2,2'-bipyridyl were added to the filtrate and stirred for 5 minutes using a stirrer. Thereafter, the absorbance of the supernatant was measured at a wavelength of 520 nm using a ratio beam spectrophotometer U-1800 manufactured by Hitachi, Ltd.

[0099] The results of the iron adsorption test conducted in Example 10 are shown in Table 5. A higher liquid absorbance (dimensionless) value indicates a higher iron ion concentration, while a lower liquid absorbance value indicates a lower iron ion concentration.

[0100]

[0101] As shown in Table 5, it was demonstrated that the use of the adsorption cartridge of the present invention filled with adsorbent G made it possible to remove iron ions from an aqueous solution containing iron ions.

[0102] (Selective Removal Test of First Transition Metals) Example 11 A working liquid sample of an absorption solution containing copper and molybdenum was filtered through a filter to remove copper oxide precipitates to prepare a test solution, and the copper and molybdenum concentrations in the test solution were measured using an ICP optical emission spectrometer (manufactured by Thermo Fisher Scientific K.K., trade name "ICAP575 Mark II"). 10 mL of the test solution and 1 g of adsorbent B were placed in a beaker, and stirred for 8 hours using a stirrer (manufactured by AS ONE Corporation, trade name "Hot Stirrer REXIM RSH-1AN") under room temperature (approximately 25°C) and atmospheric pressure conditions, and then the copper and molybdenum concentrations in the test solution were measured using the ICP optical emission spectrometer.

[0103] The results of the adsorption test carried out in Example 11 are shown in Table 6. In Table 6, "before treatment" refers to the state before adsorbent B was added to the test liquid, and "after treatment" refers to the state after adsorbent B was added to the test liquid and stirred for 8 hours using a stirrer.

[0104]

[0105] As shown in Table 6, the copper concentration in the test solution before adding adsorbent B to the test solution (before treatment) was 1.6 to 2.0 ppm, whereas the copper concentration in the test solution after adding adsorbent B to the test solution and stirring it with a stirrer for 8 hours (after treatment) was less than 1 ppm, indicating that copper in the test solution could be removed by adsorbent B. In contrast, the molybdenum concentrations in the test solution before treatment and after treatment were both 29 ppm, unchanged, indicating that molybdenum in the test solution was not removed by adsorbent B. These results demonstrate that adsorbent B, the adsorbent of the present invention, can selectively remove only copper from an aqueous solution containing copper and molybdenum.

[0106] Variations of the present invention are described below. [Appendix 1] An adsorbent for removing a first transition metal from an aqueous solution containing the first transition metal, comprising activated carbon supporting a quinolinol compound or a dihydroxynaphthalene compound, wherein the amount of the quinolinol compound or the dihydroxynaphthalene compound supported per gram of the activated carbon is 300 to 1,750 μmol / g. [Appendix 2] The adsorbent according to Appendices 1 and 2, wherein the first transition metal is one or more metals selected from the group consisting of copper, cobalt, nickel, iron, and zinc. [Appendix 3] The adsorbent according to Appendices 1 and 2, wherein the first transition metal is copper or iron. [Appendix 4] The quinolinol compound is 2-quinolinol, 4-quinolinol, 8-quinolinol, 2-methyl-8-hydroxyquinoline, 5-fluoro-8-hydroxyquinoline, 5-chloro-8-hydroxyquinoline, 5-bromo-8-hydroxyquinoline, 5-phenyl-8-hydroxyquinoline, 8-hydroxyquinoline-5-carboxylic acid, 8-hydroxyquinoline-5-carboxylic acid methyl ester, 8-hydroxy-5-quinolyl methyl ketone, 8-hydroxy-5-quinolyl vinyl ketone, 8-hydroxy-5- 4. The adsorbent of any one of appendixes 1 to 3, comprising one or more compounds selected from the group consisting of quinolyl phenyl ketone, 5-trifluoromethyl-8-hydroxyquinoline, 5-methoxy-8-hydroxyquinoline, 5-phenoxy-8-hydroxyquinoline, 5-trimethylsilyl-8-hydroxyquinoline, 5-cyano-8-hydroxyquinoline, 5-nitro-8-hydroxyquinoline, 5-dimethylamino-8-hydroxyquinoline, 8-hydroxyquinoline-5-sulfonic acid, and 8-hydroxyquinolinol. [Appendix 5] The adsorbent according to any one of Appendices 1 to 4, wherein the dihydroxynaphthalene compound comprises one or more compounds selected from the group consisting of 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, and 2,7-dihydroxynaphthalene.[Appendix 6] The adsorbent according to any one of Appendices 1 to 5, wherein the amount of the quinolinol compound or the dihydroxynaphthalene compound supported per 1 g of the activated carbon is 400 to 1650 μmol / g. [Appendix 7] The adsorbent according to any one of Appendices 1 to 6, wherein the aqueous solution containing a first transition metal is an absorption solution used in an absorption refrigerator, an absorption water cooler / heater, or an absorption air conditioner, or an electrolyte solution for metal plating. [Appendix 8] The adsorbent according to any one of Appendices 1 to 7, wherein the concentration of the first transition metal in the aqueous solution containing the first transition metal is 0.1 to 1000 ppm. [Appendix 9] The adsorbent according to any one of Appendices 1 to 8, wherein the concentration of the first transition metal in the aqueous solution containing the first transition metal is 1 to 500 ppm. [Appendix 10] A method for producing an adsorbent for removing first transition metals from an aqueous solution containing the first transition metals, comprising a contacting step of contacting a quinolinol compound or a dihydroxynaphthalene compound with activated carbon and a solvent to obtain activated carbon supporting the quinolinol compound or the dihydroxynaphthalene compound in an amount of 300 to 1750 μmol / g per 1 g of the activated carbon. [Appendix 11] A method for producing the adsorbent according to Appendices 10 and 11, wherein the solvent comprises one or more selected from the group consisting of water, ethers, alcohols, ketones, carboxylic acids, carboxylic acid esters, amides, nitriles, halogenated hydrocarbons, and sulfoxides. [Appendix 12] A method for producing the adsorbent according to Appendices 10 and 11, wherein the solvent comprises one or more selected from the group consisting of water, tetrahydrofuran, dioxane, methanol, acetone, ethyl acetate, acetonitrile, and dimethyl sulfoxide. [Appendix 13] A method for producing an adsorbent according to any one of Appendices 10 to 12, wherein the solvent comprises one or more selected from the group consisting of water, tetrahydrofuran, dioxane, methanol, acetone, and ethyl acetate. [Appendix 14] A method for producing an adsorbent according to any one of Appendices 10 to 13, further comprising a drying step of drying the activated carbon obtained after the contacting step. [Appendix 15] An adsorption cartridge for removing first transition metals from an aqueous solution containing the first transition metals, the cartridge being packed with an adsorbent comprising activated carbon supporting a quinolinol compound or a dihydroxynaphthalene compound.[Appendix 16] The adsorption cartridge according to Appendices 15, wherein the first transition metal is one or more metals selected from the group consisting of copper, cobalt, nickel, iron, and zinc. [Appendix 17] The adsorption cartridge according to Appendices 15 or 16, wherein the first transition metal is copper or iron. [Appendix 18] The adsorption cartridge according to Appendices 15 or 16, wherein the quinolinol compound is 2-quinolinol, 4-quinolinol, 8-quinolinol, 2-methyl-8-hydroxyquinoline, 5-fluoro-8-hydroxyquinoline, 5-chloro-8-hydroxyquinoline, 5-bromo-8-hydroxyquinoline, 5-phenyl-8-hydroxyquinoline, 8-hydroxyquinoline-5-carboxylic acid, 8-hydroxyquinoline-5-carboxylic acid methyl ester, 8-hydroxy-5-quinolyl methyl ketone, 8-hydroxy-5-quinolyl vinyl ketone, 8-hydroxy-5-quinolinol 18. The adsorption cartridge of any one of claims 15 to 17, comprising one or more compounds selected from the group consisting of phenyl ketone, 5-trifluoromethyl-8-hydroxyquinoline, 5-methoxy-8-hydroxyquinoline, 5-phenoxy-8-hydroxyquinoline, 5-trimethylsilyl-8-hydroxyquinoline, 5-cyano-8-hydroxyquinoline, 5-nitro-8-hydroxyquinoline, 5-dimethylamino-8-hydroxyquinoline, 8-hydroxyquinoline-5-sulfonic acid, and 8-hydroxyquinolinol. [Appendix 19] The adsorption cartridge according to any one of Appendices 15 to 18, wherein the dihydroxynaphthalene compound comprises one or more compounds selected from the group consisting of 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, and 2,7-dihydroxynaphthalene. [Appendix 20] The adsorption cartridge according to any one of Appendices 15 to 19, wherein the amount of the quinolinol compound or the dihydroxynaphthalene compound supported per 1 g of the activated carbon is 300 to 1750 μmol / g.[Appendix 21] The adsorption cartridge according to any one of Appendices 15 to 20, wherein the amount of the quinolinol compound or the dihydroxynaphthalene compound supported per 1 g of the activated carbon is 400 to 1650 μmol / g. [Appendix 22] The adsorption cartridge according to any one of Appendices 15 to 21, wherein the aqueous solution containing a first transition metal is an absorption solution used in an absorption refrigerator, an absorption water cooler / heater, or an absorption air conditioner, or an electrolyte for metal plating. [Appendix 23] The adsorption cartridge according to any one of Appendices 15 to 22, wherein the concentration of the first transition metal in the aqueous solution containing the first transition metal is 0.1 to 1000 ppm. [Appendix 24] The adsorption cartridge according to any one of Appendices 15 to 23, wherein the concentration of the first transition metal in the aqueous solution containing the first transition metal is 1 to 500 ppm. [Appendix 25] A method for removing a first transition metal, comprising a step of passing an aqueous solution containing the first transition metal through an adsorbent filled in an adsorption cartridge to adsorb and remove the first transition metal, the adsorbent comprising activated carbon carrying a quinolinol compound or a dihydroxynaphthalene compound. [Appendix 26] The method for removing a first transition metal according to Appendices 25 and 26, wherein the first transition metal is one or more metals selected from the group consisting of copper, cobalt, nickel, iron, and zinc. [Appendix 27] The method for removing a first transition metal according to Appendices 25 and 26, wherein the first transition metal is copper or iron.[Appendix 28] The quinolinol compound is 2-quinolinol, 4-quinolinol, 8-quinolinol, 2-methyl-8-hydroxyquinoline, 5-fluoro-8-hydroxyquinoline, 5-chloro-8-hydroxyquinoline, 5-bromo-8-hydroxyquinoline, 5-phenyl-8-hydroxyquinoline, 8-hydroxyquinoline-5-carboxylic acid, 8-hydroxyquinoline-5-carboxylic acid methyl ester, 8-hydroxy-5-quinolyl methyl ketone, 8-hydroxy-5-quinolyl vinyl ketone, 8-hydroxy-5-quinolyl 28. The method for removing a first transition metal according to any one of Appendices 25 to 27, comprising one or more compounds selected from the group consisting of phenyl ketone, 5-trifluoromethyl-8-hydroxyquinoline, 5-methoxy-8-hydroxyquinoline, 5-phenoxy-8-hydroxyquinoline, 5-trimethylsilyl-8-hydroxyquinoline, 5-cyano-8-hydroxyquinoline, 5-nitro-8-hydroxyquinoline, 5-dimethylamino-8-hydroxyquinoline, 8-hydroxyquinoline-5-sulfonic acid, and 8-hydroxyquinolinol. [Appendix 29] The method for removing first transition metals according to any one of Appendices 25 to 28, wherein the dihydroxynaphthalene compound comprises one or more compounds selected from the group consisting of 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, and 2,7-dihydroxynaphthalene. [Appendix 30] The method for removing first transition metals according to any one of Appendices 25 to 29, wherein the amount of the quinolinol compound or the dihydroxynaphthalene compound supported per 1 g of the activated carbon is 300 to 1750 μmol / g. [Appendix 31] The method for removing first transition metals according to any one of Appendices 25 to 30, wherein the amount of the quinolinol compound or the dihydroxynaphthalene compound supported per 1 g of the activated carbon is 400 to 1650 μmol / g.[Appendix 32] The method for removing a first transition metal according to any one of Appendices 25 to 31, wherein the aqueous solution containing the first transition metal is an absorption solution used in an absorption refrigerator, an absorption water cooler / heater, or an absorption air conditioner, or an electrolyte for metal plating. [Appendix 33] The method for removing a first transition metal according to any one of Appendices 25 to 32, wherein the concentration of the first transition metal in the aqueous solution containing the first transition metal is 0.1 to 1000 ppm. [Appendix 34] The method for removing a first transition metal according to any one of Appendices 25 to 33, wherein the concentration of the first transition metal in the aqueous solution containing the first transition metal is 1 to 500 ppm. [Appendix 35] A method for producing an aqueous solution from which a first transition metal has been removed, comprising the step of passing an aqueous solution containing the first transition metal through an adsorbent filled in an adsorption cartridge to adsorb and remove the first transition metal, wherein the adsorbent comprises activated carbon supporting a quinolinol compound or a dihydroxynaphthalene compound. [Appendix 36] A method for producing an aqueous solution from which a first transition metal has been removed according to Appendix 35, wherein the first transition metal is one or more metals selected from the group consisting of copper, cobalt, nickel, iron, and zinc. [Appendix 37] A method for producing an aqueous solution from which a first transition metal has been removed according to Appendix 35 or 36, wherein the first transition metal is copper or iron.[Appendix 38] The quinolinol compound is 2-quinolinol, 4-quinolinol, 8-quinolinol, 2-methyl-8-hydroxyquinoline, 5-fluoro-8-hydroxyquinoline, 5-chloro-8-hydroxyquinoline, 5-bromo-8-hydroxyquinoline, 5-phenyl-8-hydroxyquinoline, 8-hydroxyquinoline-5-carboxylic acid, 8-hydroxyquinoline-5-carboxylic acid methyl ester, 8-hydroxy-5-quinolyl methyl ketone, 8-hydroxy-5-quinolyl vinyl ketone, 8-hydroxy-5-quinolyl phenyl ketone 38. A method for producing an aqueous solution from which a first transition metal has been removed according to any one of Appendices 35 to 37, comprising one or more compounds selected from the group consisting of 8-hydroxyquinoline, 5-trifluoromethyl-8-hydroxyquinoline, 5-methoxy-8-hydroxyquinoline, 5-phenoxy-8-hydroxyquinoline, 5-trimethylsilyl-8-hydroxyquinoline, 5-cyano-8-hydroxyquinoline, 5-nitro-8-hydroxyquinoline, 5-dimethylamino-8-hydroxyquinoline, 8-hydroxyquinoline-5-sulfonic acid, and 8-hydroxyquinolinol. [Appendix 39] The method for producing an aqueous solution from which a first transition metal has been removed according to any one of Appendices 35 to 38, wherein the dihydroxynaphthalene compound comprises one or more compounds selected from the group consisting of 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, and 2,7-dihydroxynaphthalene. [Appendix 40] The method for producing an aqueous solution from which a first transition metal has been removed according to any one of Appendices 35 to 39, wherein an amount of the quinolinol compound or the dihydroxynaphthalene compound supported per 1 g of the activated carbon is 300 to 1750 μmol / g. [Appendix 41] The method for producing an aqueous solution from which a first transition metal has been removed according to any one of Appendices 35 to 40, wherein the amount of the quinolinol compound or the dihydroxynaphthalene compound supported per 1 g of the activated carbon is 400 to 1650 μmol / g.[Appendix 42] The method for producing an aqueous solution from which a first transition metal has been removed according to any one of Appendices 35 to 41, wherein the aqueous solution containing a first transition metal is an absorption solution used in an absorption chiller, an absorption water cooler / heater, or an absorption air conditioner, or an electrolytic solution for metal plating. [Appendix 43] The method for producing an aqueous solution from which a first transition metal has been removed according to any one of Appendices 35 to 42, wherein the concentration of the first transition metal in the aqueous solution containing the first transition metal is 0.1 to 1000 ppm. [Appendix 44] The method for producing an aqueous solution from which a first transition metal has been removed according to any one of Appendices 35 to 43, wherein the concentration of the first transition metal in the aqueous solution containing the first transition metal is 1 to 500 ppm.

[0107] REFERENCE SIGNS LIST 10 Activated carbon 12 Micropores 14 Mesopores 16 Macropores 1 Adsorption cartridge 2 Housing 3 Head 31 Water inlet 32 ​​Water outlet pipe 33 Water outlet 34 Support member 35 Plate 36 Annular protrusion 4 Filter member 41 Adsorbent 42 Outer cylinder 43 Inner cylinder 44 Hollow portion

Claims

1. An adsorbent for removing first transition metals from an aqueous solution containing the first transition metals, comprising activated carbon carrying a quinolinol compound or a dihydroxynaphthalene compound, wherein the amount of the quinolinol compound or the dihydroxynaphthalene compound carried per 1 g of the activated carbon is 300 to 1750 μmol / g.

2. The adsorbent of claim 1, wherein the first transition metal is one or more metals selected from the group consisting of copper, cobalt, nickel, iron, and zinc.

3. The quinolinol compound is 2-quinolinol, 4-quinolinol, 8-quinolinol, 2-methyl-8-hydroxyquinoline, 5-fluoro-8-hydroxyquinoline, 5-chloro-8-hydroxyquinoline, 5-bromo-8-hydroxyquinoline, 5-phenyl-8-hydroxyquinoline, 8-hydroxyquinoline-5-carboxylic acid, 8-hydroxyquinoline-5-carboxylic acid methyl ester, 8-hydroxy-5-quinolyl methyl ketone, 8-hydroxy-5-quinolyl vinyl ketone, 8-hydroxy-5- 3. The adsorbent of claim 1 or 2, comprising one or more compounds selected from the group consisting of quinolyl phenyl ketone, 5-trifluoromethyl-8-hydroxyquinoline, 5-methoxy-8-hydroxyquinoline, 5-phenoxy-8-hydroxyquinoline, 5-trimethylsilyl-8-hydroxyquinoline, 5-cyano-8-hydroxyquinoline, 5-nitro-8-hydroxyquinoline, 5-dimethylamino-8-hydroxyquinoline, 8-hydroxyquinoline-5-sulfonic acid, and 8-hydroxyquinolinol.

4. The adsorbent according to claim 1 or 2, wherein the dihydroxynaphthalene compound comprises one or more compounds selected from the group consisting of 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, and 2,7-dihydroxynaphthalene.

5. The adsorbent according to claim 1 or 2, wherein the aqueous solution containing the first transition metal is an absorption solution used in an absorption refrigerator, an absorption water cooler / heater, or an absorption air conditioner, or an electrolyte for metal plating.

6. A method for producing an adsorbent for removing first transition metals from an aqueous solution containing the first transition metals, comprising a contacting step of contacting a quinolinol compound or a dihydroxynaphthalene compound with activated carbon and a solvent to obtain activated carbon carrying 300 to 1750 μmol / g of the quinolinol compound or the dihydroxynaphthalene compound per 1 g of the activated carbon.

7. An adsorption cartridge for removing first transition metals from an aqueous solution containing said first transition metals, the cartridge being packed with an adsorbent comprising activated carbon carrying a quinolinol compound or a dihydroxynaphthalene compound.

8. The sorbent cartridge of claim 7, wherein the first transition metal is one or more metals selected from the group consisting of copper, cobalt, nickel, iron, and zinc.

9. A method for removing first transition metals, comprising the step of passing an aqueous solution containing the first transition metal through an adsorbent packed in an adsorption cartridge to adsorb and remove the first transition metals, wherein the adsorbent comprises activated carbon carrying a quinolinol compound or a dihydroxynaphthalene compound.

10. A method for producing an aqueous solution from which first transition metals have been removed, comprising the step of passing an aqueous solution containing the first transition metals through an adsorbent packed in an adsorption cartridge to adsorb and remove the first transition metals, wherein the adsorbent comprises activated carbon carrying a quinolinol compound or a dihydroxynaphthalene compound.

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