JP2015120873A - Low swellable composition and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a low swellable composition consisting of a hydrophilic polymer composition containing an amine-based polymer, which is stable in a wet state by filling to a column.SOLUTION: There is provided a low swellable composition having swelling property after a crosslinking treatment in a range of 80 to 200 wt.%, by crosslinking a polymer in a composition containing 10 to 40 mass% of (A) an amine-based polymer having an amino group or a quaternary ammonium group in a repeating unit and 60 to 90 mass% of (B) a hydrophilic polymer composition having no amino group nor quaternary ammonium group in a repeating unit by a crosslinking agent.

Description

  The present invention relates to a low swelling composition. More specifically, the present invention relates to a low-swelling composition comprising a hydrophilic polymer composition containing an amine-based polymer that can be used in a wet state after being packed in a column.

  In recent years, an adsorbent in which hydrophilic polymer particles having functional groups are packed in a column is used in a method for separating and recovering a metal from a metal-containing material or a method for separating and purifying biological components such as immunoglobulin from plasma. The method is drawing attention.

  For example, Patent Document 1 includes a polymer blend including an amine polymer and a hydrophilic polymer, and the amine polymer includes at least one selected from the group consisting of primary to tertiary amines in a repeating unit. A liquid mass transfer material, which is a polymer having a liquid, is disclosed, and it is described that the liquid mass transfer material is excellent in adsorption and elution of metal ions.

  Similarly, Patent Document 2 is a metal comprising a molded article composed of polyvinyl alcohol and an amine polymer, wherein the polyvinyl alcohol is 70% by weight or more and the boiling loss is 30% by weight or less. An ion recovery material is disclosed, and it is described that the metal recovery material is excellent in metal ion adsorption and elution and durability.

  Patent Document 3 discloses an affinity functional group in which a water-soluble polymer having no cross-linked structure is immobilized by covalent bonding as an adsorbent for immunoglobulin or bovine serum albumin and covalently bonded to the water-soluble polymer site. A packing material for packing a column is disclosed.

International Publication No. 2007/018138 Pamphlet JP 2010-138430 A JP 2008-232764 A

  When recovering metal ions adsorbed on and eluted from the metal ion adsorbent, the metal ion adsorbent is brought into contact with the solution containing the metal ions to adsorb the metal ions onto the metal ion adsorbent, and then the eluent and Contact is made to elute metal ions from the metal ion adsorbent. Since the above adsorption / elution operation may be performed at room temperature or at a high temperature, suppression of swelling of the adsorbent at a high temperature around 75 ° C. is important in handling. For example, when the in-liquid mass transfer material described in Patent Document 1 is used as a metal ion adsorbent, there is a problem that when used at a high temperature, the adsorbent swells significantly, and the adsorption performance deteriorates when used repeatedly. . In addition, it was difficult to use the column.

  However, Patent Document 2 also has not studied the swelling characteristics of the metal ion recovery material, and there is room for improvement in the swelling characteristics.

  In Patent Document 3, since the inside of the pores of a porous particle made of a synthetic polymer has a structure filled with a water-soluble polymer, there is a limit to the amount of adsorptive functional groups introduced, and contact with the liquid to be treated However, there is a problem that the adsorbent is further improved.

  Therefore, the first object of the present invention is to provide a low-swelling composition composed of a hydrophilic polymer containing a functional group, which is suitable for being repeatedly used in a wet state as an adsorbent by filling a column. Is an offer.

  The second object of the present invention is to provide a method for producing the low swelling composition.

  Furthermore, the third object of the present invention is to provide a metal ion adsorbent having excellent metal ion adsorptivity and elution properties and improved swelling characteristics, using the low swelling composition obtained above. That is.

  The fourth object of the present invention is to provide a metal recovery method using the metal ion adsorbent.

  As a result of intensive studies on a material containing an amine polymer, a hydrophilic polymer, and a crosslinking agent in order to solve the above problems, the present inventors have reached the present invention.

The first constitution of the present invention is 10 to 40% by mass of an amine polymer (A) having an amino group or a quaternary ammonium group in the repeating unit, and hydrophilic having no amino group or quaternary ammonium group in the repeating unit. Polymer (B) 60-90 mass% [The sum total of a polymer (A) and a polymer (B) is 100 mass%. And a polymer having a swelling property (weight after mass immersion in water at 75 ° C. for 10 minutes / dry weight × 100) of 80 to 200 mass after crosslinking with a crosslinking agent (C). % Low swellable composition.
In the present invention, the composition means a mixture containing at least the polymer (A) and the polymer (B) and, if necessary, other polymers, crosslinking agents, fine particles, or various additives. .

  In the low swelling composition of the present invention, the hydrophilic polymer (B) is preferably an ethylene-vinyl alcohol copolymer.

In the low swellable composition of the present invention, the amine polymer (A) is preferably polyethyleneimine or polyallylamine, and the hydrophilic polymer (B) is preferably an ethylene-vinyl alcohol copolymer.

  In the low swellable composition of the present invention, the crosslinking agent (C) is a compound containing at least two functional groups selected from the group consisting of an epoxy group, an isocyanate group and a vinyl group. Preferably there is.

  The low swellable composition of the present invention contains 0.10 to 10% by mass of fine particles (D) with respect to 100% by mass of the resin component of the hydrophilic polymer (B) and the amine polymer (A), The average particle diameter of the fine particles (D) is preferably 0.012 to 20 μm.

  In the low swelling composition of the present invention, the fine particles (D) are at least one kind of fine particles selected from the group consisting of silicon oxide, titanium oxide, calcium carbonate, magnesium silicate, aluminum silicate, polystyrene, and crosslinked acrylic. It is preferable.

  The low-swelling composition of the present invention is preferably in the form of particles and the particle diameter is in the range of 0.1 to 2.0 mm. Moreover, it is preferable that the low swellable composition of this invention is fibrous form, and the fiber diameter exists in the range of 10-1000 micrometers.

  In the second configuration of the present invention, the amine polymer (A), the hydrophilic polymer (B), and the cross-linking agent (C) are kneaded using a biaxial kneader to form a predetermined shape, A method for producing the low-swelling composition as described above, wherein a crosslinking treatment is performed simultaneously with and / or after molding.

  The third configuration of the present invention is a metal ion adsorbent containing the low swelling composition.

  A fourth configuration of the present invention is a method for recovering a metal from a solution containing metal ions, wherein the metal ions in the solution are adsorbed on the metal ion adsorbent, and the adsorbed metal ions Is recovered from the metal ion adsorbent with an eluent.

  In the above recovery method, the metal to be recovered is preferably a platinum group metal.

  In the above recovery method, the metal ion-containing solution is a solution containing hydrogen chloride, and the eluent contains at least one selected from the group consisting of sodium hydroxide, ammonia, and thiourea. Is preferred.

  Since the low swelling composition according to the first configuration of the present invention includes an amine polymer having an amino group or a quaternary ammonium group and a hydrophilic polymer having no such group, a metal or biopolymer In addition to its excellent adsorptivity, etc., it has low swellability due to the introduction of cross-linking bonds, excellent column packing properties, and can be used stably in a wet state. Useful as an adsorbent.

  According to the method for producing a low swellable composition according to the second configuration of the present invention, since a biaxial kneader is used, an amine polymer (A) and a hydrophilic polymer (B) are optionally added. It is possible to obtain a resin composition in which the fine particles (D) to be uniformly mixed are obtained, and the resulting composition is pulverized to efficiently obtain particles of a low-swelling composition of a predetermined size Can do. The cross-linking treatment with a cross-linking agent can be performed after being formed into particles, or the cross-linking treatment can be performed during the molding by adding a cross-linking agent during kneading.

  The metal adsorbent according to the third configuration of the present invention is excellent in the adsorption and elution properties of metal ions, and further has a lower swelling rate than the conventional one under heating. Therefore, even if the metal ion adsorbent of the present invention is repeatedly used, excellent adsorptivity and elution are maintained. Since the swellability of the metal ion adsorbent of the present invention is suppressed, the column packed with the metal ion adsorbent of the present invention is less likely to deteriorate and has a long column life. According to the metal ion recovery method of the present invention using the metal ion adsorbent, metals (particularly platinum group metals) can be recovered as metal ions with high efficiency and low cost by a simple operation. Also suitable.

  According to the metal recovery method according to the fourth configuration of the present invention, the metal ion adsorbent according to the third configuration of the present invention is excellent in metal (especially platinum group metal) adsorptivity. Metal can be recovered as metal ions efficiently and at low cost. Furthermore, since the swelling property of the low-swelling composition according to the first configuration of the present invention is suppressed, the column filled with the metal ion adsorbent according to the fourth configuration of the present invention is unlikely to deteriorate, Suitable for repeated use because the column life is extended.

(Low swelling composition)
The low swelling composition of the present invention has 10 to 40% by mass of an amine-based polymer (A) having an amino group or a quaternary ammonium group in the repeating unit and no amino group or quaternary ammonium group in the repeating unit. The polymer in the composition containing 60 to 90% by mass of the hydrophilic polymer (B) is crosslinked with a crosslinking agent (C), and the swelling property after the crosslinking treatment (mass after immersion in water at 75 ° C. for 10 minutes / The dry mass × 100) is in the range of 80 to 200% by mass.

(Amine polymer)
The low swelling composition of the present invention contains an amine polymer (A) as a resin component, and the amine polymer (A) adsorbs an adsorbed substance such as a metal ion at an amino group and a quaternary ammonium group. The amino group of the amine polymer (A) may be any of primary amino group, secondary amino group, and tertiary amino group, and is preferably primary amino group or secondary amino group. The repeating unit having an amino group may be one type or two or more types. Accordingly, the amine-based polymer (A) may be a polymer in which two or more kinds of repeating units having an amino group or a quaternary ammonium group are random, block, alternating, or graft copolymerized. Moreover, within the range which does not inhibit the effect of this invention, you may have a repeating unit which does not have an amino group or a quaternary ammonium group.

  The amine-based polymer (A) includes polyvinylamine, polyvinylalkylamine, polyalkyleneimine, quaternary ammonium-containing polymer, polyaniline, polynucleotide, polyallylamine, polyalkyleneamine, polydiallyl quaternary ammonium and a group thereof. At least one selected from the above is preferably used, and a copolymer obtained by copolymerizing two or more repeating units of these polymers can also be preferably used. More preferably, at least one selected from the group consisting of polyvinylamine, polyallylamine, polyalkyleneamine, polydiallyl quaternary ammonium, and salts thereof is used.

  From the viewpoint of the density of the adsorption points to the adsorbed substance and the ease of polymer synthesis, the amine polymer (A) may have 10 to 35 amino groups and quaternary ammonium groups per number average molecular weight of 1,000. preferable. The number average molecular weight of the amine-based polymer (A) can be determined by, for example, dissolving it in a solvent in which the amine-based polymer can be dissolved and using gel permeation chromatography (GPC).

  The weight average molecular weight of the amine polymer (A) is preferably 5,000 to 100,000, more preferably 10,000 to 70,000 in order to prevent elution from the low swelling composition. In addition, the weight average molecular weight of an amine polymer (A) can be calculated | required, for example using GPC.

(Hydrophilic polymer)
The low swellable composition of the present invention contains a hydrophilic polymer (B) as a resin component, and the hydrophilic polymer (B) imparts moldability and durability to the low swellable composition. The hydrophilic polymer (B) used in the present invention refers to a polymer having a hydrophilic group such as a hydroxyl group, an ether group, a carboxyl group, or an amide group in a repeating unit. Examples of the hydrophilic polymer (B) include polyvinyl alcohol, ethylene-vinyl alcohol copolymer, polyvinyl butyral, polyvinyl acetal, polyvinyl alkyl alcohol, polyalkylene glycol, polyvinyl alkyl ether, polyacrylic acid, polymethacrylic acid, polyalkylene oxide, At least one selected from the group consisting of polyacrylamide, polyamide, and polyamino acid is preferably used. These polymers may have other comonomer units (eg, monomer units having unsaturated carboxylic acid units such as maleic acid, itaconic acid, acrylic acid, silanol groups, aldehyde groups, or sulfonic acid groups). The content of the comonomer unit is preferably 10 mol% or less, more preferably 5% mol or less, based on all monomer units.

  As the hydrophilic polymer (B), polyvinyl alcohol, ethylene-vinyl alcohol copolymer, polyvinyl butyral, polyvinyl acetal and polyamide are preferable, and the acid resistance of the low swelling composition is improved. More preferred is coalescence. At this time, the content of ethylene units is preferably 20 to 50 mol%, more preferably 27 to 48 mol% in all monomer units. If the ethylene content is less than 20 mol%, the durability of the molded article may be deteriorated. On the other hand, when the ethylene content exceeds 50 mol%, the hydrophilicity of the low swellable composition is lowered, and when the low swellable composition is used as a metal ion adsorbent, suitable adsorbability and elution property of metal ions are obtained. May be worse. Moreover, when the hydrophilic polymer (B) is an ethylene-vinyl alcohol copolymer, it is preferable to use polyethyleneimine as the amine-based polymer (A) from the viewpoint of the adsorptivity of an adsorbed substance such as a metal ion. On the other hand, when the hydrophilic polymer (B) is an ethylene-vinyl alcohol copolymer, it is preferable to use polyallylamine as the amine-based polymer (A) from the viewpoint of elution of metal ions and the like.

  The weight average molecular weight of the hydrophilic polymer (B) is not particularly limited, but is, for example, 10,000 to 500,000, preferably 20,000 to 400,000. In addition, the weight average molecular weight of hydrophilic polymer (B) can be calculated | required, for example using GPC. In the case of less than 10,000, there is a concern of the elution of the hydrophilic polymer (B) from the low swelling composition. If it exceeds 500,000, the moldability may deteriorate.

(Composition ratio of amine polymer and hydrophilic polymer)
The content of the amine polymer (A) in the resin component [total amount of (A) and (B)] of the low swellable composition of the present invention is 10 to 40% by mass. When the content of the amine-based polymer (A) is less than 10% by mass, for example, when a low-swelling composition is used for the metal adsorbent, the number of metal ion adsorption points becomes too small, and the metal recovery efficiency is high. Deteriorate. On the other hand, when it is more than 40% by mass, the moldability is poor. For example, when molding into resin pellets, the strands are easily stuck together, and the miscibility with the hydrophilic polymer (B) is deteriorated, resulting in high durability. I cannot get sex. The content of the amine polymer (A) is preferably 20 to 35% by mass.

  Content of the hydrophilic polymer (B) in the resin component of the low swelling composition of this invention is 60-90 mass%. When the content of the hydrophilic polymer (B) is less than 60% by mass, the mixing property with the amine polymer (A) and the moldability are deteriorated, and the durability of the molded product is lowered or swelled. The characteristics may deteriorate. On the other hand, if the content of the hydrophilic polymer (B) is more than 90% by mass, the characteristics of the amine-based polymer constituting the low swellable composition are hardly exhibited. The content of the hydrophilic polymer (B) is preferably 65 to 80% by mass.

  In addition, the low swelling composition of this invention may contain polymers other than an amine polymer (A) and a hydrophilic polymer (B) as a resin component within the range which does not inhibit the effect of this invention.

(Crosslinking agent)
The low-swelling composition of the present invention is packed in a column by crosslinking a polymer in a composition containing an amine polymer (A) and a hydrophilic polymer (B) as a resin component with a crosslinking agent (C). It has the property of being stable in a wet state. The crosslinking agent (C) used in the present invention is an epoxy group, an isocyanate group, a vinyl group, a carboxyl group, a halogen group, an acid anhydride group, an acid halide from the viewpoint of the chemical stability of the resulting low swelling composition. And compounds containing at least two functional groups selected from a group, N-chloroformyl group, chloroformate group, imide ether group, amidinyl group, aldehyde group and the like. More preferably, at least one selected from the group consisting of an epoxy group, an isocyanate group, and a vinyl group is used. More preferably, it is a compound having an epoxy group, and is a polyvalent epoxy compound having 2 to 5 functional groups. In addition, the above-described crosslinking with a crosslinking agent containing an aldehyde group tends to be deacetalized by heating in an aqueous solution containing an acid, and is not preferable in terms of acid resistance depending on the application.
By the crosslinking treatment with the crosslinking agent (C), a hydrophilic group in the hydrophilic polymer (B) and / or a functional group such as an amino group in the amine-based polymer (A) reacts with the crosslinking agent to make hydrophilic. Between polymer (B) and hydrophilic polymer (B), between amine-based polymer (A) and amine-based polymer (A), and / or between amine-based polymer (A) and hydrophilic polymer (B). Crosslinks are introduced in between.

  Specific examples of the crosslinking agent (C) are listed below. Examples of the above-mentioned crosslinking agent (C) having a vinyl group include divinyl sulfone, “NK ester” (1G, 2G, 3G, 4G, 9G, 14G, 23G, BPE-80N, BPE— manufactured by Shin-Nakamura Chemical Co., Ltd. 100, BPE-200, BPE-500, BPE-900, BPE-1300, DCP, DOD-N, HD-N, NOD-N, NPG, 1206PE, 701, PG, TMPT) and the like. It is done.

  Examples of the crosslinking agent (C) having an epoxy group include “Denacol” manufactured by Nagase ChemteX Corporation (EX-611, EX-612, EX-614, EX-614B, EX-622, EX-512, EX-521, EX-411, EX-421, EX-313, EX-314, EX-321, EX-201, EX-211, EX-212, EX-252, EX-810, EX-811, EX- 850, EX-851, EX-821, EX-830, EX-832, EX-841, EX-861, EX-911, EX-941, EX-920, EX-931, EX-721, EX-203, EX-711, EX-221, etc.), bisphenol A diglycidyl ether, bisphenol A diβ methyl glycidyl ether, bisphenol F Diglycidyl ether of glycidyl ether, tetrahydroxyphenylmethane tetraglycidyl ether, resorcinol diglycidyl ether, brominated bisphenol A diglycidyl ether, chlorinated bisphenol A diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, bisphenol A alkylene oxide adduct Glycidyl ether type such as novolak glycidyl ether, polyalkylene glycol diglycidyl ether, glycerin triglycidyl ether, pentaerythritol diglycidyl ether, epoxy urethane resin; glycidyl ether ester type such as p-oxybenzoic acid glycidyl ether ester; Acid diglycidyl ester, tetrahydrophthalic acid diglycidyl ester Glycidyl ester types such as diglycidyl ester of hexahydrophthalic acid, diglycidyl acrylate and dimer acid diglycidyl ester; glycidyl amine types such as glycidyl aniline, tetraglycidyl diaminodiphenylmethane, triglycidyl isocyanurate and triglycidyl aminophenol; Linear aliphatic epoxy resins such as epoxidized polybutadiene and epoxidized soybean oil; 3,4-epoxy-6-methylcyclohexylmethyl 3,4-epoxy-6-methylcyclohexanecarboxylate, 3,4-epoxycyclohexylmethyl 3, 4-epoxycyclohexanecarboxylate, bis (3,4-epoxy-6-methylcyclohexylmethyl) adipate, vinylcyclohexene diepoxide, dicyclopenta Examples thereof include alicyclic epoxy resins such as diene oxide, bis (2,3-epoxycyclopentyl) ether, and limonene dioxide.

  Examples of the crosslinking agent (C) having an isocyanate group include “Duranate” manufactured by Asahi Kasei Chemicals Corporation (WB40-100, WB40-80D, WE50-100, WT30-100, WT20-100, etc.); (TDI); hydrogenated TDI; trimethylolpropane-TDI adduct (eg, “DesmodurL” manufactured by Bayer); triphenylmethane triisocyanate; methylenebis (phenylisocyanate) (MDI); hydrogenated MDI; polymerized MDI; hexamethylene diisocyanate Xylylene diisocyanate; 4,4′-dicyclohexylmethane diisocyanate; isophorone diisocyanate and the like. Isocyanates dispersed in water using an emulsifier can also be used.

The crosslinking agent (C) contained in the low swellable composition of the present invention improves the swelling characteristics by reducing the water content of the low swellable composition, particularly at high temperatures.
When the swelling property (75 ° C., in water) of the low swelling composition according to the present invention (measurement method of swelling property is described later) exceeds 200% by mass, the composition is remarkably easily swelled and formed from the composition described later. The filter formed into a tablet shape, honeycomb shape, sheet shape, cylindrical shape, etc. from a molded product such as a particulate or fibrous product has cracks or a housing (column etc.) in which the filter is loaded. The filter is likely to break due to swelling of the filter. For this reason, the swelling characteristic of the low swelling composition needs to be 200% by mass or less, preferably 190% by mass or less, and more preferably 180% by mass or less.
On the other hand, when the swelling property is less than 80% by mass, the permeability of the solution containing the adsorbed substance such as metal ions into the composition becomes insufficient, and thus sufficient adsorbability required as an adsorbent is obtained. It becomes difficult to obtain. For this reason, the swelling characteristic of the low swelling composition needs to be 80% by mass or more, preferably 90% by mass or more, and more preferably 100% by mass.

(Fine particles)
The average particle diameter of the fine particles (D) is 0.012 to 20 μm. If the average particle size of the fine particles (D) is less than 0.012 μm, the effect of reducing the swelling of the low swelling composition cannot be obtained sufficiently. On the other hand, when the average particle diameter of the fine particles (D) is larger than 20 μm, the mixing property with the resin component and the moldability are deteriorated, and the swelling property of the low swelling composition is deteriorated. The average particle diameter of the fine particles (D) is preferably 0.02 to 10 μm. The average particle diameter of the fine particles (D) is calculated by, for example, using a laser diffraction / scattering particle size distribution measuring device, irradiating the particle group with laser light, and calculating from the intensity distribution pattern of the diffracted / scattered light emitted therefrom. It can be determined by determining the particle size distribution.

  As the fine particles (D), inorganic fine particles such as silicon oxide, titanium oxide, calcium carbonate, magnesium silicate, and aluminum silicate, and organic fine particles such as polystyrene and cross-linked acrylic can be suitably used. These can be used in combination. The fine particles (D) are more preferably inorganic fine particles (particularly at least one selected from the group consisting of silicon oxide, titanium oxide, calcium carbonate, magnesium silicate, and aluminum silicate) from the viewpoint of swelling characteristics. The organic fine particles do not include the fine particles of the polymers (A) and (B).

  The content of the fine particles (D) may be 0.10 to 10% by mass with respect to 100% by mass of the resin component. If the content of the fine particles (D) is too small, the effect of reducing the water content of the low swelling composition may not be sufficiently obtained. On the other hand, when there is too much content of microparticles | fine-particles (D), there exists a possibility that the mixability of a resin component and a moldability may worsen. Moreover, when a low swelling composition is used as a metal ion adsorbent, the metal recovery efficiency may be deteriorated. The content of the fine particles (D) is preferably 0.5 to 5% by mass.

(Other ingredients)
The low swellable composition of the present invention may further contain optional components other than the amine polymer (A), the hydrophilic polymer (B), and the crosslinking agent (C). Therefore, various additives such as an antioxidant, a stabilizer, a lubricant, a processing aid, an antistatic agent, a colorant, an impact resistance aid, and a foaming agent may be blended as necessary.

(Production of low swelling composition)
The low swellable composition of the present invention is prepared by mixing, for example, an amine polymer (A), a hydrophilic polymer (B), a crosslinking agent (C), and, if necessary, fine particles (D) and optional components according to a known method. Can be manufactured. As a preferable production method, a method (melt kneading method) of melt-kneading the amine polymer (A), the hydrophilic polymer (B), the fine particles (D) and an optional component using a biaxial kneader is exemplified. It is done. According to the melt kneading method, there is an advantage that it is easy to obtain a particulate material in which each component is uniformly dispersed. The crosslinking agent (C) can be made into a low-swelling composition by introducing a crosslinking bond into a particulate material. As the melt kneading method, specifically, for example, a hydrophilic polymer (B) is melt kneaded by a twin screw extruder, and a predetermined amount of amine polymer (A) and fine particles (D) are added from the side feeder. These can be mixed and carried out. Furthermore, the melt-kneaded product can be extruded to form molded bodies of various shapes, and further, can be immersed in a solution containing a crosslinking agent (C) to be subjected to crosslinking treatment. C) can be added to melt-knead the polymer and introduce cross-linking. Furthermore, the molded body can be pulverized into a particulate low-swelling composition.

  As another production method of the low swelling composition, for example, an amine polymer (A), a hydrophilic polymer (B), and, if necessary, a mixture of fine particles (D) and optional components are prepared. As the solvent, water is usually used, but an organic solvent such as dimethyl sulfoxide may be used. A solution having good properties can be obtained by adding both polymers to a solvent and raising the temperature while stirring. The mixture of the amine polymer (A), the hydrophilic polymer (B), and the fine particles (D) is extruded through a spinning nozzle by a wet or dry / wet method and solidified in a coagulation bath, or is extruded into an air bath by dry spinning. Then, it can be crystallized by wet stretching, drying, and dry heat stretching according to a conventional method, and can be made into a fibrous shaped product, and further immersed in a solution containing a crosslinking agent (C) for crosslinking treatment.

(Shape of low swelling composition)
The low-swelling composition is molded into various shapes such as particles, flakes, fibers, sheets, fabrics, and three-dimensional shapes depending on the application, and the low-swelling composition can be obtained as a simple substance. Is particulate. The particle diameter is not particularly limited, but is preferably 0.1 to 2.0 mm, and more preferably 0.3 to 1.0 mm. In addition, a particle diameter shows the value classified by sieving.

  The simple substance of the low swelling composition may be fibrous. Although there is no restriction | limiting in particular in the fiber diameter, it is preferable that it is 10-1000 micrometers, More preferably, it is 25-500 micrometers. The fiber diameter can be obtained, for example, by sampling a short fiber randomly, observing a cross section of the fiber with an electron microscope, and measuring the fiber diameter.

(Adsorbent packed column)
The low swellable composition containing the polymer (A) and the polymer (B) and having a cross-linked bond according to the present invention is in various forms such as particles, flakes, fibers, sheets, fabrics, and three-dimensional shapes. It is formed into a single piece of shape and is usually packed in a column and used as an adsorbent.
The treated water at 75 ° C. was introduced into the aggregate in which the column-shaped aggregates, such as particulates, fibers, flakes, etc., or the sheet-like or fabric-like single bodies were wound and laminated. When the low-swelling composition is swelled with a cross-linking bond introduced so as to swell and contain water in the range of 80 to 200% by weight of water per 100% by weight of the low-swelling composition, Keeps liquid permeability while maintaining a predetermined shape without being fused to each other, and the individual single members constituting the assembly are individually separated in a swollen state and can be taken out Filled with. Thus, the low swelling composition simple substance according to the present invention is packed in a column and used as an adsorbent that can be used even at a high temperature of 75 ° C.

(Metal ion adsorbent)
A metal ion adsorbent is mentioned as a suitable use of the low swelling composition concerning this invention. The metal ion adsorbent containing the low-swelling composition can maintain excellent metal ion adsorbability, elution properties, and swelling characteristics.

(Metal recovery method)
The metal ion adsorbent containing the low swellable composition of the present invention is excellent in metal ion adsorption and elution, and has low swelling characteristics and small swelling. In particular, the swelling rate in the vicinity of 75 ° C. is small. Therefore, even if the metal ion adsorbent containing the low swellable composition of the present invention is used repeatedly, excellent adsorbability and elution are maintained, and the metal ion adsorbent containing the low swellable composition of the present invention is filled. Such a column is less likely to deteriorate and has a long column life. By using the metal ion adsorbent containing the low swellable composition of the present invention, metals (particularly platinum group metals) can be recovered as metal ions from a solution containing metal ions with high efficiency and low cost by a simple operation. can do. This collection operation is also suitable for repeated execution.

  The method of recovering a metal from a solution containing metal ions according to the present invention includes adsorbing metal ions in the solution to the metal ion adsorbent containing the low-swelling composition, and adsorbing the metal ions. Eluting from the metal ion adsorbent with an eluent.

Adsorption of metal ions by the above metal ion adsorbent can be performed, for example, by the following method.
When the metal ion adsorbent is in the form of particles, the column is filled with metal ion adsorbent particles and a solution containing metal ions is passed through.
-The metal ion adsorbent particles are put into a solution containing metal ions, and the metal ions are adsorbed and then pulled up.
The metal ion adsorbent particles are processed into a filter formed into a tablet shape, a honeycomb shape, a sheet shape, or a cylindrical shape, filled in a column, and a solution containing metal ions is passed therethrough.
・ If the metal ion adsorbent is fibrous, wrap the metal ion adsorbent fiber around a cylindrical core with holes on the side, and pass the solution containing metal ions from the inside of the cylinder to the outside or vice versa. Liquid.
-A metal ion adsorbent fiber is cut into an appropriate length (for example, 0.5 to 10 mm), filled into a column, and a solution containing metal ions is passed through.
-A metal ion adsorbent fiber is cut into a desired length, put into a solution containing metal ions, pulled up after adsorbing metal ions.
-Metal ion adsorbent fibers are processed into sheets of paper, non-woven fabric, woven fabric, etc., stacked and filled into a column, and a solution containing metal ions is passed through.

  The solution for adsorbing metal ions by the metal ion adsorbent containing the low swellable composition of the present invention is preferably a solution containing hydrogen chloride. The metal ion adsorbent containing the low swellable composition of the present invention is preferably applied to the adsorption recovery of platinum group metals as described below, but platinum group metals are stable as chloro complexes in aqueous solutions containing hydrogen chloride. It is believed that it is present and is usually recovered in a 1-6N aqueous hydrogen chloride solution.

  The elution of the metal ions from the metal ion adsorbent by the eluent can be performed by putting the metal ion adsorbent adsorbing the metal ions into the eluent. Further, when the metal ion adsorbent is packed in the column, it can also be carried out by passing an eluent. The type of the eluent may be appropriately selected according to the type of metal ion, but the eluent preferably contains at least one selected from the group consisting of sodium hydroxide, ammonia and thiourea.

(Metal recovered)
Examples of metals that can be recovered include platinum group metals such as platinum, palladium, rhodium, osmium, iridium, ruthenium, gold, silver, copper, nickel, chromium, vanadium, cobalt, lead, zinc, mercury, cadmium, etc. It is done. Since the metal ion adsorbent containing the low-swelling composition according to the present invention has excellent water resistance and durability, it is particularly suitable for recovering platinum group metals that are recovered in hydrochloric acid.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated in detail, this invention is not limited to these Examples. In addition, each numerical value in an Example was computed with the following method.

(Swelling characteristics)
A 100 mg sample of the low swelling composition is put into 100 mL of 3N hydrochloric acid at 20 ° C. containing platinum group metal ions at a concentration of 100 mg / L, and stirred for 60 minutes. A sample of the low swellable composition is taken out of the solution, the attached liquid is wiped off, immersed in water, and stirred at 25 ° C., 45 ° C. and 75 ° C. for 10 minutes. Next, the low-swelling composition sample is taken out of the solution, and the sample is centrifuged and dehydrated and weighed (A), and then dried at 105 ° C. for 4 hours and weighed (B). Swelling characteristics (sometimes referred to as swelling ratio) are obtained from the following formula.
Swelling property = [(A−B) / B] × 100 (%)

(Low-swelling composition column take-out property)
After filling the column with low-swellable composition particles and passing a 3 ° C 3N hydrochloric acid solution containing platinum group metal ions from the top to the bottom of the column, water at 75 ° C is passed in the same manner. Next, after removing the low swellable composition sample from the column and centrifuging and dewatering the sample (A), sieving with a sieve having a diameter 1.5 times the particle size of the low swellable composition used. To do. The particles (B) that have passed through the sieve are weighed. The passing rate is obtained from the following equation.
Passing rate = [(A−B) / A] × 100 (%)
When the pass rate is 100%, the swelling of the particles is suppressed, and the column spillability of the low swellable composition is “◯”, and when it is 80 to 99%, the column spillability of the low swellable composition is When “Δ” is 80% or less, the low-swelling composition column take-out property is evaluated as “x”.

(Metal adsorption amount)
A 100 mg sample of a metal ion adsorbent composed of a low swellable composition is put into 100 mL of 3N hydrochloric acid at 20 ° C. containing platinum group metal ions at a concentration of 100 mg / L and stirred for 60 minutes. Thereafter, 1 mL of the solution is sampled, and the metal concentration measured with an ICP emission analyzer (IRIS-AP manufactured by Nippon Jarrell Ash) is defined as C (mg / L). The metal adsorption amount is obtained from the following equation.
Metal adsorption amount per gram of sample = 100-C (mg / g)

(Elution rate)
The sample after the adsorption amount measurement is taken out of the solution, wiped off the adhering liquid, immersed in 20 mL of a 50 g / L thiourea solution for 10 minutes to elute the metal, 1 mL of the eluent is sampled, and the ICP emission spectrometer is used. The metal concentration is measured (D mg / L). The elution rate is obtained from the following equation.
Elution rate = [(D / 50) / {(100-C) / 10}] × 100 (%)

[Example 1]
As the hydrophilic polymer (B), a polyvinyl alcohol having a polymerization degree of 1700 and a saponification degree of 98.5 mol% (manufactured by Kuraray Co., Ltd., PVA117 (trade name)), and an amine polymer (A) having a weight average molecular weight of 10,000. Polyethyleneimine (manufactured by Nippon Shokubai Co., Ltd., Epomin SP-200 (trade name)) was used. 80% by mass of polyvinyl alcohol and 20% by mass of polyethyleneimine were dissolved in water. The solution was wet-spun into a saturated sodium sulfate bath at 40 ° C. from a nozzle having a diameter of 0.08 mm and a pore number of 1000, and the formed yarn was wet-stretched twice and then dried at 130 ° C. and 5 times at 230 ° C. Was subjected to dry heat stretching. Subsequently, this fiber was subjected to a crosslinking treatment in an aqueous solution of 25 ° C. having a concentration of 5% by mass of an epoxy compound (manufactured by Nagase ChemteX Corporation, Denacol EX-314 (trade name)) [crosslinking agent (C)] A fibrous low-swelling composition was obtained (average fiber diameter: 25 μm). The swelling property in water was measured about the obtained low swelling composition. Moreover, about the metal ion adsorption material which consists of the said low swelling composition, the adsorption amount and elution rate of the platinum group were measured. The results are shown in Table 1.

[Example 2]
As a hydrophilic polymer (B), an ethylene-vinyl alcohol copolymer having an ethylene content of 44 mol% (manufactured by Kuraray Co., Ltd., Eval E-105B (trade name)), and an amine polymer (A) having a weight average molecular weight of 10,000 Polyethyleneimine (manufactured by Nippon Shokubai Co., Ltd., Epomin SP-200 (trade name)) was used. An ethylene-vinyl alcohol copolymer is melt-kneaded at 210 ° C. with a lab plast mill, a predetermined amount of polyethyleneimine is added thereto, the content of polyethyleneimine is 25% by mass, and the content of ethylene-vinyl alcohol copolymer is contained. The two polymers were mixed so that the amount was 75% by mass. After kneading for a predetermined time, the resin composition was taken out, and the obtained resin composition was pulverized by a pulverizer to obtain a particulate material having a particle diameter of 0.2 to 0.5 mm. Subsequently, the particulate matter was subjected to a crosslinking treatment in an aqueous solution of 25 ° C. having a concentration of 2% by mass of an epoxy compound (manufactured by Nagase ChemteX Corporation, Denacol EX-810 (trade name)) [crosslinking agent (C)]. . The obtained low-swelling composition was classified into particles having a particle diameter of 0.2 to 0.5 mm using a sieve, and then the swelling property in water was measured and the removal property in a column was evaluated. Further, the adsorption amount and elution rate of the platinum group were measured for the metal ion adsorbent comprising the low swelling composition. The results are shown in Table 1.

[Example 3]
As the hydrophilic polymer (B), an ethylene-vinyl alcohol copolymer having an ethylene content of 44 mol% (manufactured by Kuraray Co., Ltd., Eval E-105B (trade name)) and an amine-based polymer (A) having a weight average molecular weight of 15000 Polyallylamine (manufactured by Nittobo Co., Ltd., PAA-15C (trade name)) was used. An ethylene-vinyl alcohol copolymer is melt-kneaded at 210 ° C. with a lab plast mill, a predetermined amount of polyallylamine is added thereto, the content of polyallylamine is 25% by mass, and the content of ethylene-vinyl alcohol copolymer is contained. The two polymers were mixed so that the amount was 75% by mass. After kneading for a predetermined time, the resin composition was taken out, and the obtained resin composition was pulverized by a pulverizer to obtain a particulate material having a particle diameter of 0.2 to 0.5 mm. Subsequently, this particulate material was subjected to a crosslinking treatment in an aqueous solution of 25 ° C. having a concentration of 5% by mass of an epoxy compound (manufactured by Nagase ChemteX Corp., Denacol EX-810 (trade name)) [crosslinking agent (C)]. went. The obtained low-swelling composition was classified into particles having a particle diameter of 0.2 to 0.5 mm using a sieve, and then the swelling property in water was measured and the removal property in a column was evaluated. Further, the adsorption amount and elution rate of the platinum group were measured for the metal ion adsorbent comprising the low swelling composition. The results are shown in Table 1.

[Example 4]
As the hydrophilic polymer (B), nylon 6 (manufactured by Ube Industries, UBE nylon 5033B (trade name)), and amine-based polymer (A), polyethyleneimine (manufactured by Nippon Shokubai Co., Ltd.) having a weight average molecular weight of 10,000. Epomin SP-200 (trade name)) was used. Nylon 6 is melt kneaded at 210 ° C. with a lab plast mill, and a predetermined amount of polyethyleneimine is added thereto, so that the content of polyethyleneimine is 25 mass% and the content of nylon 6 is 75 mass%. The seed polymer was mixed. After kneading for a predetermined time, the resin composition was taken out, and the obtained resin composition was pulverized by a pulverizer to obtain a particulate material having a particle diameter of 0.2 to 0.5 mm. Subsequently, the particulate material was subjected to a crosslinking treatment in an aqueous solution at 25 ° C. having a concentration of 1% by mass of an epoxy compound (Denacol EX-314 (trade name) manufactured by Nagase ChemteX Corporation) [crosslinking agent (C)]. . The obtained low swellable composition was classified into particles having a particle diameter of 0.2 to 0.5 mm using a sieve, and then the swelling property in water was measured. Further, the adsorption amount and elution rate of the platinum group were measured for the metal ion adsorbent comprising the low swelling composition. The results are shown in Table 1.

[Example 5]
As a hydrophilic polymer (B), an ethylene-vinyl alcohol copolymer having an ethylene content of 32 mol% (manufactured by Kuraray Co., Ltd., Eval F-104A (trade name)), and an amine-based polymer (A) having a weight average molecular weight 10000 polyethyleneimine (manufactured by Nippon Shokubai Co., Ltd., Epomin SP-200 (trade name)) was used. An ethylene-vinyl alcohol copolymer is melt-kneaded at 210 ° C. with a lab plast mill, a predetermined amount of polyethyleneimine is added thereto, the content of polyethyleneimine is 25% by mass, and the content of ethylene-vinyl alcohol copolymer is contained. The two polymers were mixed so that the amount was 75% by mass. After kneading for a predetermined time, the resin composition was taken out, and the obtained resin composition was pulverized by a pulverizer to obtain a particulate material having a particle diameter of 0.2 to 0.5 mm. Subsequently, the particulate material was subjected to a crosslinking treatment in an aqueous solution of 25 ° C. having a concentration of 2% by mass of an epoxy compound (Denacol EX-810 (trade name) manufactured by Nagase ChemteX Corporation) [crosslinking agent (C)]. . The obtained low swellable composition was classified into particles having a particle diameter of 0.2 to 0.5 mm using a sieve, and then the swelling property in water was measured. Moreover, about the metal ion adsorption material which consists of the said low swelling composition, the adsorption amount and elution rate of the platinum group were measured. The results are shown in Table 1.

[Example 6]
As a hydrophilic polymer (B), an ethylene-vinyl alcohol copolymer having an ethylene content of 48 mol% (manufactured by Kuraray Co., Ltd., Eval G-156B (trade name)), and an amine polymer (A) having a weight average molecular weight 10000 polyethyleneimine (manufactured by Nippon Shokubai Co., Ltd., Epomin SP-200 (trade name)) was used. An ethylene-vinyl alcohol copolymer is melt-kneaded at 210 ° C. with a lab plast mill, a predetermined amount of polyethyleneimine is added thereto, the content of polyethyleneimine is 25% by mass, and the content of ethylene-vinyl alcohol copolymer is contained. The two polymers were mixed so that the amount was 75% by mass. After kneading for a predetermined time, the resin composition was taken out, and the obtained resin composition was pulverized by a pulverizer to obtain a particulate material having a particle diameter of 0.2 to 0.5 mm. Subsequently, the particulate material was subjected to a crosslinking treatment in an aqueous solution of 25 ° C. having a concentration of 2% by mass of an epoxy compound (Denacol EX-810 (trade name) manufactured by Nagase ChemteX Corporation) [crosslinking agent (C)]. . The obtained low swellable composition was classified into particles having a particle diameter of 0.2 to 0.5 mm using a sieve, and then the swelling property in water was measured. Moreover, about the metal ion adsorption material which consists of the said low swelling composition, the adsorption amount and elution rate of the platinum group were measured. The results are shown in Table 1.

[Example 7]
As a hydrophilic polymer (B), an ethylene-vinyl alcohol copolymer having an ethylene content of 44 mol% (manufactured by Kuraray Co., Ltd., Eval E-105B (trade name)), and an amine polymer (A) having a weight average molecular weight 10000 polyethyleneimine (manufactured by Nippon Shokubai Co., Ltd., Epomin SP-200 (trade name)) was used. An ethylene-vinyl alcohol copolymer is melt-kneaded at 210 ° C. with a lab plast mill, a predetermined amount of polyethyleneimine is added thereto, the content of polyethyleneimine is 10% by mass, and the content of ethylene-vinyl alcohol copolymer is contained. The two polymers were mixed so that the amount was 90% by mass. After kneading for a predetermined time, the resin composition was taken out, and the obtained resin composition was pulverized by a pulverizer to obtain a particulate material having a particle diameter of 0.2 to 0.5 mm. Subsequently, the particulate material was subjected to a crosslinking treatment in an aqueous solution having a concentration of 25 ° C. and an epoxy compound (Denacol EX-512 (trade name) manufactured by Nagase ChemteX Corporation) [crosslinking agent (C)] of 5 mass%. . The obtained low-swelling composition was classified into particles having a particle diameter of 0.2 to 0.5 mm using a sieve, and then the swelling property in water was measured and the removal property in a column was evaluated. Further, the adsorption amount and elution rate of the platinum group were measured for the metal ion adsorbent comprising the low swelling composition. The results are shown in Table 1.

[Example 8]
As a hydrophilic polymer (B), an ethylene-vinyl alcohol copolymer having an ethylene content of 44 mol% (manufactured by Kuraray Co., Ltd., Eval E-105B (trade name)), and an amine polymer (A) having a weight average molecular weight 10000 polyethyleneimine (manufactured by Nippon Shokubai Co., Ltd., Epomin SP-200 (trade name) was used. The ethylene-vinyl alcohol copolymer was melt-kneaded at 210 ° C. with a lab plast mill, and polyethyleneimine was placed there. After quantitative addition, two types of polymers were mixed so that the content of polyethyleneimine was 40% by mass and the content of ethylene-vinyl alcohol copolymer was 60% by mass. The product is taken out, and the resulting resin composition is pulverized by a pulverizer to obtain a particulate product having a particle size of 0.2 to 0.5 mm. Subsequently, the particulate material was subjected to a crosslinking treatment in an aqueous solution of 25 ° C. having a concentration of 5% by mass with an epoxy compound (Denacol EX-810 (trade name) manufactured by Nagase ChemteX Corp.). The obtained low swellable composition was classified into particles having a particle diameter of 0.2 to 0.5 mm using a sieve, and then the swelling property in water was measured. The metal ion adsorbent comprising the composition was measured for the platinum group adsorption amount and elution rate, and the results are shown in Table 1.

[Example 9]
As the hydrophilic polymer (B), an ethylene-vinyl alcohol copolymer having an ethylene content of 44 mol% (manufactured by Kuraray Co., Ltd., Eval E-105B (trade name)) and an amine-based polymer (A) having a weight average molecular weight of 10,000 Polyethyleneimine (manufactured by Nippon Shokubai Co., Ltd., Epomin SP-200 (trade name)) and polyallylamine having a weight average molecular weight of 15000 (manufactured by Nittobo Co., Ltd., PAA-15C (trade name)) were used. An ethylene-vinyl alcohol copolymer is melt-kneaded at 210 ° C. with a lab plast mill, and a predetermined amount of polyethyleneimine and polyallylamine is added thereto, so that the total content of polyethyleneimine and polyallylamine is 30% by mass (polyethyleneimine). And 3 types of polymers were mixed so that the content ratio of polyethyleneimine to the total of polyallylamine was 50%) and the content of ethylene-vinyl alcohol copolymer was 70% by mass. After kneading for a predetermined time, the resin composition was taken out, and the obtained resin composition was pulverized by a pulverizer to obtain a particulate material having a particle diameter of 0.2 to 0.5 mm. Subsequently, the particulate product was subjected to a crosslinking treatment in an aqueous solution of 25% by weight of an epoxy compound (Denacol EX-810 (trade name) manufactured by Nagase ChemteX Corp.) [crosslinking agent (C)]. The obtained low swellable composition was classified into particles having a particle diameter of 0.2 to 0.5 mm using a sieve, and then the swelling property in water was measured. Further, the adsorption amount and elution rate of the platinum group were measured for the metal ion adsorbent comprising the low swelling composition. The results are shown in Table 1.

[Example 10]
As the hydrophilic polymer (B), an ethylene-vinyl alcohol copolymer having an ethylene content of 44 mol% (manufactured by Kuraray Co., Ltd., Eval E-105B (trade name)) and an amine-based polymer (A) having a weight average molecular weight of 10,000 Polyethyleneimine (manufactured by Nippon Shokubai Co., Ltd., Epomin SP-200 (trade name)), and quaternary ammonium-containing polymer having a weight average molecular weight of 40000 (manufactured by Nittobo Co., Ltd., diallyldimethylammonium chloride polymer PAS-H-) 5L (trade name)) was used. The ethylene-vinyl alcohol copolymer is melt-kneaded at 210 ° C. with a lab plast mill, and a predetermined amount of polyethyleneimine, quaternary ammonium-containing polymer and silicon oxide is added thereto, and the total of polyethyleneimine and quaternary ammonium-containing polymer is added. Three polymers so that the content is 25 mass% (the mass ratio of polyethyleneimine to the total of polyethyleneimine and quaternary ammonium-containing polymer is 80%), and the ethylene-vinyl alcohol copolymer content is 75 mass%. Were mixed. After kneading for a predetermined time, the resin composition was taken out, and the obtained resin composition was pulverized by a pulverizer to obtain a particulate material having a particle diameter of 0.2 to 0.5 mm. Subsequently, this particulate material was subjected to a crosslinking treatment in an aqueous solution of 25 ° C. having a concentration of 5% by mass of an epoxy compound (Denacol EX-314 (trade name) manufactured by Nagase ChemteX Corporation) [crosslinking agent (C)]. . The obtained low swellable composition was classified into particles having a particle diameter of 0.2 to 0.5 mm using a sieve, and then the swelling property in water was measured. Moreover, about the metal ion adsorption material which consists of the said low swelling composition, the adsorption amount and elution rate of the platinum group were measured. The results are shown in Table 1.

[Example 11]
As the hydrophilic polymer (B), an ethylene-vinyl alcohol copolymer having an ethylene content of 44 mol% (manufactured by Kuraray Co., Ltd., Eval E-105B (trade name)) and an amine-based polymer (A) having a weight average molecular weight of 15000 Polyallylamine (manufactured by Nittobo Co., Ltd., PAA-15C (trade name)), and a quaternary ammonium-containing polymer having a weight average molecular weight of 40000 (manufactured by Nittobo Co., Ltd., diallyldimethylammonium chloride polymer PAS-H-5L) (Trade name)) was used. An ethylene-vinyl alcohol copolymer is melt-kneaded at 210 ° C. with a lab plast mill, and a predetermined amount of polyallylamine and quaternary ammonium-containing polymer is added thereto, so that the total content of polyallylamine and quaternary ammonium-containing polymer is Three kinds of polymers were mixed so that the content of the ethylene-vinyl alcohol copolymer was 75% by mass (25% by mass (mass ratio of polyallylamine to the total of polyallylamine and quaternary ammonium-containing polymer was 80%)). . After kneading for a predetermined time, the resin composition was taken out, and the obtained resin composition was pulverized by a pulverizer to obtain a particulate material having a particle diameter of 0.2 to 0.5 mm. Subsequently, this particulate material was subjected to a crosslinking treatment in an aqueous solution of 25 ° C. having a concentration of 5% by mass of an epoxy compound (Denacol EX-314 (trade name) manufactured by Nagase ChemteX Corporation) [crosslinking agent (C)]. . The obtained low swellable composition was classified into particles having a particle diameter of 0.2 to 0.5 mm using a sieve, and then the swelling property in water was measured. Moreover, about the metal ion adsorption material which consists of the said low swelling composition, the adsorption amount and elution rate of the platinum group were measured. The results are shown in Table 1.

[Example 12]
As a hydrophilic polymer (B), an ethylene-vinyl alcohol copolymer having an ethylene content of 44 mol% (manufactured by Kuraray Co., Ltd., Eval E-105B (trade name)), and an amine polymer (A) having a weight average molecular weight 10000 polyethyleneimine (manufactured by Nippon Shokubai Co., Ltd., Epomin SP-200 (trade name)) was used. An ethylene-vinyl alcohol copolymer is melt-kneaded at 210 ° C. with a lab plast mill, a predetermined amount of polyethyleneimine is added thereto, the content of polyethyleneimine is 25% by mass, and the content of ethylene-vinyl alcohol copolymer is contained. The two polymers were mixed so that the amount was 75% by mass. After kneading for a predetermined time, the resin composition was taken out, and the obtained resin composition was pulverized by a pulverizer to obtain a particulate material having a particle diameter of 0.2 to 0.5 mm. Subsequently, the particulate material was subjected to a crosslinking treatment with an aqueous solution of 25 ° C. having a concentration of 5% by mass of an epoxy compound (Denacol EX-314 (trade name) manufactured by Nagase ChemteX Corporation) [crosslinking agent (C)]. The obtained low swellable composition was classified into particles having a particle diameter of 0.2 to 0.5 mm using a sieve, and then the swelling property in water was measured. Further, the adsorption amount and elution rate of the platinum group were measured for the metal ion adsorbent comprising the low swelling composition. The results are shown in Table 1.

[Example 13]
As the hydrophilic polymer (B), an ethylene-vinyl alcohol copolymer having an ethylene content of 44 mol% (manufactured by Kuraray Co., Ltd., Eval E-105B (trade name)), and a polyethyleneimine having a weight average molecular weight of 10,000 (stock) Nippon Shokubai Epomin SP-200 (trade name)) was used. An ethylene-vinyl alcohol copolymer is melt-kneaded at 210 ° C. with a lab plast mill, a predetermined amount of polyethyleneimine is added thereto, the content of polyethyleneimine is 25% by mass, and the content of ethylene-vinyl alcohol copolymer is contained. The two polymers were mixed so that the amount was 75% by mass. After kneading for a predetermined time, the resin composition was taken out, and the obtained resin composition was pulverized by a pulverizer to obtain a particulate material having a particle diameter of 0.2 to 0.5 mm. Subsequently, the particulate material was subjected to a crosslinking treatment with an epoxy compound (Denacol EX-512 (trade name) manufactured by Nagase Chemtex Co., Ltd.) [crosslinking agent (C)] in an aqueous solution at 25 ° C. having a concentration of 5% by mass. The obtained low swellable composition was classified into particles having a particle diameter of 0.2 to 0.5 mm using a sieve, and then the swelling property in water was measured. Moreover, the adsorption amount and elution rate of the platinum group were measured about the metal ion adsorption material which consists of the said low swelling composition. The results are shown in Table 1.

[Example 14]
As a hydrophilic polymer (B), an ethylene-vinyl alcohol copolymer having an ethylene content of 44 mol% (manufactured by Kuraray Co., Ltd., Eval E-105B (trade name)), and an amine polymer (A) having a weight average molecular weight 10000 polyethyleneimine (manufactured by Nippon Shokubai Co., Ltd., Epomin SP-200 (trade name)) was used. An ethylene-vinyl alcohol copolymer is melt-kneaded at 210 ° C. with a lab plast mill, a predetermined amount of polyethyleneimine is added thereto, the content of polyethyleneimine is 25% by mass, and the content of ethylene-vinyl alcohol copolymer is contained. The two polymers were mixed so that the amount was 75% by mass. After kneading for a predetermined time, the resin composition was taken out, and the obtained resin composition was pulverized by a pulverizer to obtain a particulate material having a particle diameter of 0.2 to 0.5 mm. Subsequently, the particulate product was subjected to crosslinking treatment in an aqueous solution at 25 ° C. with a concentration of 6% by mass of a polyfunctional isocyanate compound (Duranate WB40-100 (trade name) manufactured by Asahi Kasei Chemicals Corporation). went. The obtained low swellable composition was classified into particles having a particle diameter of 0.2 to 0.5 mm using a sieve, and then the swelling property in water was measured. Further, the adsorption amount and elution rate of the platinum group were measured for the metal ion adsorbent comprising the low swelling composition. The results are shown in Table 1.

[Example 15]
As a hydrophilic polymer (B), an ethylene-vinyl alcohol copolymer having an ethylene content of 44 mol% (manufactured by Kuraray Co., Ltd., Eval E-105B (trade name)), and an amine polymer (A) having a weight average molecular weight 10000 polyethyleneimine (manufactured by Nippon Shokubai Co., Ltd., Epomin SP-200 (trade name)) was used. An ethylene-vinyl alcohol copolymer is melt-kneaded at 210 ° C. with a lab plast mill, a predetermined amount of polyethyleneimine is added thereto, the content of polyethyleneimine is 25% by mass, and the content of ethylene-vinyl alcohol copolymer is contained. The two polymers were mixed so that the amount was 75% by mass. After kneading for a predetermined time, the resin composition was taken out, and the obtained resin composition was pulverized by a pulverizer to obtain a particulate material having a particle diameter of 0.2 to 0.5 mm. Subsequently, the particulate material was subjected to a crosslinking treatment in an aqueous solution at 25 ° C. having a concentration of 5% by mass with a vinyl group compound (NK ester A-400 (trade name) manufactured by Shin-Nakamura Chemical Co., Ltd.). went. The obtained low-swelling composition was classified into particles having a particle diameter of 0.2 to 0.5 mm using a sieve, and then the evaluation of the swelling property in water and the evaluation of the column taking-out property were performed. Further, the adsorption amount and elution rate of the platinum group were evaluated for the metal ion adsorbent comprising the low-swelling composition. The results are shown in Table 1.

[Example 16]
As the hydrophilic polymer (B), an ethylene-vinyl alcohol copolymer having an ethylene content of 44 mol% (manufactured by Kuraray Co., Ltd., Eval E-105B (trade name)) and an amine-based polymer (A) having a weight average molecular weight of 10,000 Polyethyleneimine (manufactured by Nippon Shokubai Co., Ltd., Epomin SP-200 (trade name)) and fine particles (D), silicon oxide having an average particle size of 0.03 μm (manufactured by Nippon Aerosil Co., Ltd., Aerosil 50 (trade name) )) Was used. An ethylene-vinyl alcohol copolymer is melt-kneaded at 210 ° C. with a lab plast mill, to which a predetermined amount of polyethyleneimine and silicon oxide are added, and the content of polyethyleneimine is 25% by mass. Two types of polymers and fine particles were mixed so that the coal content was 74 mass% and the silicon oxide content was 1 mass%. After kneading for a predetermined time, the resin composition was taken out, and the obtained resin composition was pulverized by a pulverizer to obtain a particulate material having a particle diameter of 0.2 to 0.5 mm. Subsequently, the particulate material was subjected to a crosslinking treatment with an epoxy compound (Denacol EX-810 (trade name) manufactured by Nagase Chemtex Co., Ltd.) [crosslinking agent (C)] in an aqueous solution at 25 ° C. with a concentration of 2% by mass. The obtained low-swelling composition was classified into particles having a particle diameter of 0.2 to 0.5 mm using a sieve, and then the swelling property in water was measured and the removal property in a column was evaluated. Further, the adsorption amount and elution rate of the platinum group were measured for the metal ion adsorbent composed of the low swelling composition. The results are shown in Table 1.

[Example 17]
As the hydrophilic polymer (B), an ethylene-vinyl alcohol copolymer having an ethylene content of 44 mol% (manufactured by Kuraray Co., Ltd., Eval E-105B (trade name)) and an amine-based polymer (A) having a weight average molecular weight of 15000 Polyallylamine (manufactured by Nittobo Co., Ltd., PAA-15C (trade name)) and fine particles (D), silicon oxide having an average particle size of 0.03 μm (manufactured by Nippon Aerosil Co., Ltd., Aerosil 50 (trade name)) ) Was used. An ethylene-vinyl alcohol copolymer is melt-kneaded at 210 ° C. with a lab plast mill, and a predetermined amount of polyallylamine and silicon oxide are added thereto, so that the content of polyallylamine is 25% by mass, ethylene-vinyl alcohol copolymer weight Two types of polymers and fine particles were mixed so that the coal content was 74 mass% and the silicon oxide content was 1 mass%. After kneading for a predetermined time, the resin composition was taken out, and the obtained resin composition was pulverized by a pulverizer to obtain a particulate material having a particle diameter of 0.2 to 0.5 mm. Subsequently, the particulate material was subjected to a crosslinking treatment in an aqueous solution of 25 ° C. having a concentration of 2% by mass of an epoxy compound (Denacol EX-810 (trade name) manufactured by Nagase ChemteX Corporation) [crosslinking agent (C)]. . The obtained low swellable composition was classified into particles having a particle diameter of 0.2 to 0.5 mm using a sieve, and then the swelling property in water was measured. Further, the adsorption amount and elution rate of the platinum group were measured for the metal ion adsorbent comprising the low swelling composition. The results are shown in Table 1.

[Example 18]
As the hydrophilic polymer (B), an ethylene-vinyl alcohol copolymer having an ethylene content of 44 mol% (manufactured by Kuraray Co., Ltd., Eval E-105B (trade name)) and an amine-based polymer (A) having a weight average molecular weight of 10,000 Polyethylene imine (manufactured by Nippon Shokubai Co., Ltd., Epomin SP-200 (trade name)) and fine particles (D), calcium carbonate having an average particle size of 1.0 μm (Sankyo Flour Milling Co., Ltd., Escalon # 2300 (commercial product) Name)). The ethylene-vinyl alcohol copolymer is melt-kneaded at 210 ° C. with a lab plast mill, and a predetermined amount of polyethyleneimine and calcium carbonate is added thereto, so that the content of polyethyleneimine is 25% by mass, and the ethylene-vinyl alcohol copolymer is added. Two polymers and fine particles were mixed so that the content of the polymer was 74% by mass and the content of calcium carbonate was 1% by mass. After kneading for a predetermined time, the resin composition was taken out, and the obtained resin composition was pulverized by a pulverizer to obtain a particulate material having a particle diameter of 0.2 to 0.5 mm. Subsequently, the particulate material was subjected to a crosslinking treatment in an aqueous solution of 25% by weight of 2% by mass of an epoxy compound (Denacol EX-810 (trade name) manufactured by Nagase ChemteX Corporation) [crosslinking agent (C)]. The obtained low swellable composition was classified into particles having a particle diameter of 0.2 to 0.5 mm using a sieve, and then the swelling property in water was measured. Further, the adsorption amount and elution rate of the platinum group were measured for the metal ion adsorbent comprising the low swelling composition. The results are shown in Table 1.

[Example 19]
As the hydrophilic polymer (B), an ethylene-vinyl alcohol copolymer having an ethylene content of 44 mol% (manufactured by Kuraray Co., Ltd., Eval E-105B (trade name)) and an amine-based polymer (A) having a weight average molecular weight of 10,000 Polyethyleneimine (manufactured by Nippon Shokubai Co., Ltd., Epomin SP-200 (trade name)) and fine particles (D), silicon oxide having an average particle diameter of 14.0 μm (manufactured by Tosoh Silica Co., Ltd., NIPGEL, BY- 001 (trade name)) was used. An ethylene-vinyl alcohol copolymer is melt-kneaded at 210 ° C. with a lab plast mill, and a predetermined amount of polyethyleneimine and silicon oxide are added thereto. The content of polyethyleneimine is 20% by mass, and ethylene-vinyl alcohol copolymer is added. Two kinds of polymers and fine particles were mixed so that the coal content was 75% by mass and the silicon oxide content was 5% by mass. After kneading for a predetermined time, the resin composition was taken out, and the obtained resin composition was pulverized by a pulverizer to obtain a particulate material having a particle diameter of 0.2 to 0.5 mm. Subsequently, the particulate material was subjected to a crosslinking treatment in an aqueous solution of 25% by weight of 2% by mass of an epoxy compound (Denacol EX-810 (trade name) manufactured by Nagase ChemteX Corporation) [crosslinking agent (C)]. The obtained low swellable composition was classified into particles having a particle diameter of 0.2 to 0.5 mm using a sieve, and then the swelling property in water was measured. Moreover, for the metal ion adsorbent comprising the low-swelling composition,
The adsorption amount and elution rate of the platinum group were measured. The results are shown in Table 1.

[Example 20]
As the hydrophilic polymer (B), an ethylene-vinyl alcohol copolymer having an ethylene content of 44 mol% (manufactured by Kuraray Co., Ltd., Eval E-105B (trade name)) and an amine-based polymer (A) having a weight average molecular weight of 10,000 Polyethyleneimine (manufactured by Nippon Shokubai Co., Ltd., Epomin SP-200 (trade name)) and fine particles (D), silicon oxide having an average particle diameter of 0.02 μm (manufactured by Nippon Aerosil Co., Ltd., Aerosil 90G (trade name) )) Was used. An ethylene-vinyl alcohol copolymer is melt-kneaded at 210 ° C. with a lab plast mill, and a predetermined amount of polyethyleneimine and silicon oxide are added thereto. The content of polyethyleneimine is 20% by mass, and ethylene-vinyl alcohol copolymer is added. Two kinds of polymers and fine particles were mixed so that the coal content was 70% by mass and the silicon oxide content was 10% by mass. After kneading for a predetermined time, the resin composition was taken out, and the obtained resin composition was pulverized by a pulverizer to obtain a particulate material having a particle diameter of 0.2 to 0.5 mm. Subsequently, the particulate material was subjected to a crosslinking treatment with an epoxy compound (Denacol EX-810 (trade name) manufactured by Nagase Chemtex Co., Ltd.) [crosslinking agent (C)] in an aqueous solution at 25 ° C. with a concentration of 2% by mass. The obtained low swellable composition was classified into particles having a particle diameter of 0.2 to 0.5 mm using a sieve, and then the swelling property in water was measured. Further, the adsorption amount and elution rate of the platinum group were measured for the metal ion adsorbent comprising the low swelling composition. The results are shown in Table 1.

[Comparative Example 1]
As the hydrophilic polymer (B), polyvinyl alcohol having a polymerization degree of 1700 and a saponification degree of 99 mol% (manufactured by Kuraray Co., Ltd., PVA117 (trade name)), and an amine polymer (A) having a weight average molecular weight of 15000 Allylamine (manufactured by Nittobo Co., Ltd., PAA-15C (trade name)) was used. Polyvinyl alcohol 95% by mass and polyallylamine 5% by mass were dissolved in water. The solution was wet-spun into a saturated sodium sulfate bath at 40 ° C. from a nozzle having a diameter of 0.08 mm and a pore number of 1000, and the formed yarn was wet-stretched twice and then dried at 130 ° C. and 5 times at 230 ° C. Was subjected to dry heat stretching. Subsequently, this fiber was subjected to a crosslinking treatment in an aqueous solution of 1% by mass of glutaraldehyde as a crosslinking agent (C) and 2% by mass of maleic acid at 40 ° C. to obtain a fibrous composition (average) Fiber diameter: 25 μm). The obtained composition was subjected to measurement of swelling properties in water. Further, the platinum group adsorption amount and elution rate of the metal ion adsorbent comprising the composition were measured. The results are shown in Table 1.

[Comparative Example 2]
As the hydrophilic polymer (B), polyvinyl alcohol having a polymerization degree of 1700 and a saponification degree of 99 mol% (manufactured by Kuraray Co., Ltd., PVA117 (trade name)), and an amine polymer (A) having a weight average molecular weight of 15000 Allylamine (manufactured by Nittobo Co., Ltd., PAA-15C (trade name)) was used. Polyvinyl alcohol 50% by mass and polyallylamine 50% by mass were dissolved in water. Although the solution was wet-spun into a saturated sodium sulfate bath at 40 ° C. from a nozzle having a diameter of 0.08 mm and a pore number of 1000, yarn formation was not possible and a fibrous composition could not be obtained.

[Comparative Example 3]
As the hydrophilic polymer (B), polyvinyl alcohol having a polymerization degree of 1700 and a saponification degree of 99 mol% (manufactured by Kuraray Co., Ltd., PVA117 (trade name)), and an amine polymer (A) having a weight average molecular weight of 15000 Allylamine (manufactured by Nittobo Co., Ltd., PAA-15C (trade name)) was used. 80% by mass of polyvinyl alcohol and 20% by mass of polyallylamine were dissolved in water. The solution was wet-spun into a saturated sodium sulfate bath at 40 ° C. from a nozzle having a diameter of 0.08 mm and a pore number of 1000, and the formed yarn was wet-stretched twice and then dried at 130 ° C. and 5 times at 230 ° C. Was subjected to dry heat stretching. Subsequently, this fiber was subjected to a crosslinking treatment in an aqueous solution of 40 ° C. having a concentration of 1% by mass of glutaraldehyde and 2% by mass of maleic acid as a crosslinking agent (C) to obtain a fibrous composition (average fiber diameter : 25 μm). The obtained composition was subjected to measurement of swelling characteristics in water, and evaluation of column take-out properties. Further, the platinum group adsorption amount and elution rate of the metal ion adsorbent comprising the composition were measured. The results are shown in Table 1.

[Comparative Example 4]
As a hydrophilic polymer (B), an ethylene-vinyl alcohol copolymer having an ethylene content of 44 mol% (manufactured by Kuraray Co., Ltd., Eval E-105B (trade name)), and an amine polymer (A) having a weight average molecular weight 10000 polyethyleneimine (manufactured by Nippon Shokubai Co., Ltd., Epomin SP-200 (trade name)) was used. An ethylene-vinyl alcohol copolymer is melt-kneaded at 210 ° C. with a lab plast mill, a predetermined amount of polyethyleneimine is added thereto, the content of polyethyleneimine is 5% by mass, and the content of ethylene-vinyl alcohol copolymer is contained. The two polymers were mixed so that the amount was 95% by mass. After kneading for a predetermined time, the resin composition was taken out, and the obtained resin composition was pulverized by a pulverizer to obtain a particulate material having a particle diameter of 0.2 to 0.5 mm. Subsequently, the particulate material was subjected to a crosslinking treatment with an epoxy compound (Denacol EX-810 (trade name) manufactured by Nagase Chemtex Co., Ltd.) [crosslinking agent (C)] in an aqueous solution at 25 ° C. with a concentration of 2% by mass. The obtained composition was classified into particles having a particle diameter of 0.2 to 0.5 mm using a sieve, and then the swelling property in water was measured. Moreover, about the metal ion adsorption material which consists of the said composition, the adsorption amount and elution rate of platinum group were measured. The results are shown in Table 1.

[Comparative Example 5]
As a hydrophilic polymer (B), an ethylene-vinyl alcohol copolymer having an ethylene content of 44 mol% (manufactured by Kuraray Co., Ltd., Eval E-105B (trade name)), and an amine polymer (A) having a weight average molecular weight 10000 polyethyleneimine (manufactured by Nippon Shokubai Co., Ltd., Epomin SP-200 (trade name)) was used. An ethylene-vinyl alcohol copolymer is melt-kneaded at 210 ° C. with a lab plast mill, a predetermined amount of polyethyleneimine is added thereto, the content of polyethyleneimine is 50 mass%, and the content of ethylene-vinyl alcohol copolymer is contained. The two polymers were mixed so that the amount was 50% by mass. After kneading for a predetermined time, removal was attempted, but the resin composition did not solidify, and the resin composition and the metal ion adsorbent composed of the resin composition could not be obtained.

[Comparative Example 6]
Instead of the hydrophilic polymer (B), polyethyleneimine (manufactured by Nippon Shokubai Co., Ltd.) having a weight average molecular weight of 10,000 as polyethylene (manufactured by Nippon Polyethylene Co., Ltd., Novatec HY420 (trade name)) and amine polymer (A) Epomin SP-200 (trade name)) was used. Polyethylene is melt-kneaded at 210 ° C. with a lab plast mill, and a predetermined amount of polyethyleneimine is added thereto, so that two types of polyethyleneimine content are 25 mass% and polyethylene content is 75 mass%. The polymer was mixed. Although kneading for a predetermined time, the resin composition was not uniformly mixed, and a metal ion adsorbent comprising the resin composition and the resin composition could not be obtained.

[Comparative Example 7]
As a hydrophilic polymer (B), an ethylene-vinyl alcohol copolymer having an ethylene content of 44 mol% (manufactured by Kuraray Co., Ltd., Eval E-105B (trade name)), and an amine polymer (A) having a weight average molecular weight 10000 polyethyleneimine (manufactured by Nippon Shokubai Co., Ltd., Epomin SP-200 (trade name)) was used. An ethylene-vinyl alcohol copolymer is melt-kneaded at 210 ° C. with a lab plast mill, a predetermined amount of polyethyleneimine is added thereto, the content of polyethyleneimine is 25% by mass, and the content of ethylene-vinyl alcohol copolymer is contained. The two polymers were mixed so that the amount was 75% by mass. After kneading for a predetermined time, the resin composition was taken out, and the obtained resin composition was pulverized by a pulverizer to obtain a particulate material having a particle diameter of 0.2 to 0.5 mm. The obtained particulate matter was classified into particles having a particle diameter of 0.2 to 0.5 mm using a sieve, and then the swelling property in water was measured and the removal property in a column was evaluated. Further, the adsorption amount and elution rate of the platinum group were measured for the particulate matter. The results are shown in Table 1.

[Comparative Example 8]
As a hydrophilic polymer (B), an ethylene-vinyl alcohol copolymer having an ethylene content of 44 mol% (manufactured by Kuraray Co., Ltd., Eval E-105B (trade name)), and an amine polymer (A) having a weight average molecular weight 15,000 polyallylamine (manufactured by Nittobo Co., Ltd., PAA-15C (trade name)) was used. An ethylene-vinyl alcohol copolymer is melt-kneaded at 210 ° C. with a lab plast mill, a predetermined amount of polyallylamine is added thereto, the content of polyallylamine is 25% by mass, and the content of ethylene-vinyl alcohol copolymer is contained. The two polymers were mixed so that the amount was 75% by mass. After kneading for a predetermined time, the resin composition was taken out, and the obtained resin composition was pulverized by a pulverizer to obtain a particulate material having a particle diameter of 0.2 to 0.5 mm. Subsequently, this particulate material was subjected to a crosslinking treatment in an aqueous solution of 25 ° C. having a concentration of 0.5% by mass of an epoxy compound (Denacol EX-810 (trade name) manufactured by Nagase ChemteX Corporation) [Crosslinking agent (C)]. went. The obtained resin composition was classified into particles having a particle diameter of 0.2 to 0.5 mm using a sieve, and then the swelling property in water was measured and the removal property in a column was evaluated. Moreover, about the metal ion adsorption material which consists of the said resin composition, the adsorption amount and elution rate of the platinum group were measured. The results are shown in Table 1.

[Comparative Example 9]
As a hydrophilic polymer (B), an ethylene-vinyl alcohol copolymer having an ethylene content of 44 mol% (manufactured by Kuraray Co., Ltd., Eval E-105B (trade name)), and an amine polymer (A) having a weight average molecular weight 15,000 polyallylamine (manufactured by Nittobo Co., Ltd., PAA-15C (trade name)) was used. An ethylene-vinyl alcohol copolymer is melt-kneaded at 210 ° C. with a lab plast mill, a predetermined amount of polyallylamine is added thereto, the content of polyallylamine is 25% by mass, and the content of ethylene-vinyl alcohol copolymer is contained. The two polymers were mixed so that the amount was 75% by mass. After kneading for a predetermined time, the resin composition was taken out, and the obtained resin composition was pulverized by a pulverizer to obtain a particulate material having a particle diameter of 0.2 to 0.5 mm. Subsequently, the particulate material was subjected to a crosslinking treatment in an aqueous solution of 25 ° C. having a concentration of 25% by mass of an epoxy compound (Denacol EX-810 (trade name) manufactured by Nagase ChemteX Corporation) [crosslinking agent (C)]. . The obtained composition was classified into particles having a particle diameter of 0.2 to 0.5 mm using a sieve, and then the swelling property in water was measured. Moreover, about the metal ion adsorption material which consists of the said composition, the adsorption amount and elution rate of platinum group were measured. The results are shown in Table 1.

（注）比較例６：親水性ポリマの代わりにポリエチレンが用いられている。

(Note) Comparative Example 6: Polyethylene is used in place of the hydrophilic polymer.

  As is apparent from Table 1, the amine polymer (A) having an amino group or quaternary ammonium group in the repeating unit (10) to 40% by mass, and hydrophilicity having no amino group or quaternary ammonium group in the repeating unit. The composition containing 60 to 90% by mass of the polymer (B) is crosslinked with the crosslinking agent (C), so that the swelling property after the crosslinking treatment is 80 to 200% by mass and the composition It is possible to obtain a metal ion adsorbent made of a material, and this metal ion adsorbent is excellent in adsorptivity and elution, and excellent in swelling characteristics.

  The low swellable composition according to the present invention is excellent in swelling properties and has an appropriate swellability, so that it can be packed in a column and used for a long time under wet conditions. In addition, the metal ion adsorbent comprising the low swellable composition of the present invention is excellent in adsorptivity and elution, and also has excellent swelling properties, so that it is possible to recover the metal under heating. Since metals such as platinum group metals can be efficiently recovered, there is industrial applicability.

  While preferred embodiments of the invention have been described above, it will be appreciated by those skilled in the art that various modifications, additions and substitutions can be made without departing from the scope and spirit of the invention as disclosed in the claims. It will be possible.

Claims (13)

  10 to 40% by mass of an amine-based polymer (A) having an amino group or quaternary ammonium group in the repeating unit, and 60 to 90% by mass of a hydrophilic polymer (B) having no amino group or quaternary ammonium group in the repeating unit. % [The total of the polymer (A) and the polymer (B) is 100% by mass. And a polymer having a swelling property (weight after mass immersion in water at 75 ° C. for 10 minutes / dry weight × 100) of 80 to 200 mass after crosslinking with a crosslinking agent (C). % Low swelling composition characterized by being in the range of%.   The low-swelling composition according to claim 1, wherein the hydrophilic polymer (B) is an ethylene-vinyl alcohol copolymer.   The low-swelling composition according to claim 1 or 2, wherein the amine-based polymer (A) is polyethyleneimine or polyallylamine, and the hydrophilic polymer (B) is an ethylene-vinyl alcohol copolymer.   4. The compound according to claim 1, wherein the cross-linking agent (C) is a compound including at least two functional groups selected from the group consisting of an epoxy group, an isocyanate group, and a vinyl group. The low swellable composition according to item.   0.10 to 10% by mass of fine particles (D) with respect to a total of 100% by mass of the polymer (A) and the polymer (B), and the average particle size of the fine particles (D) is 0.012 The low-swellable composition according to any one of claims 1 to 4, which is -20 µm.   6. The fine particles (D) according to claim 5, wherein the fine particles (D) are at least one kind of the fine particles (D) selected from the group consisting of silicon oxide, titanium oxide, calcium carbonate, magnesium silicate, aluminum silicate, polystyrene, and crosslinked acrylic. Low swellable composition.   The low swellable composition according to any one of claims 1 to 6, wherein the metal ion adsorbent is a particle having a particle diameter of 0.1 to 2.0 mm or a fiber having a fiber diameter of 10 to 1000 µm. .   After the amine-based polymer (A), the hydrophilic polymer (B), and the cross-linking agent (C) are kneaded using a biaxial kneader and molded into a predetermined shape, and / or after molding. The manufacturing method of the low swelling composition of any one of Claims 1-7 which performs a crosslinking process.   The method for producing a low swelling composition according to claim 8, further comprising adding fine particles (D) and kneading with the kneader.   The metal ion adsorption material containing the low swelling composition of any one of Claims 1-7.   A method for recovering a metal from a solution containing metal ions, comprising adsorbing the metal ions in the solution to the metal ion adsorbent according to claim 10, and the adsorbed metal ions by an eluent. A metal recovery method comprising elution from a metal ion adsorbent.   The metal recovery method according to claim 11, wherein the metal to be recovered is a platinum group metal.   The solution containing the metal ion is a solution containing hydrogen chloride, and the eluent contains at least one selected from the group consisting of sodium hydroxide, ammonia, and thiourea. Metal recovery method.