WO2009110499A1 - Method for water purification, equipment for water purification, and water purification set - Google Patents

Abstract

A method for water purification which comprises bringing a scavenger containing both a compound represented by general formula (I) and metal ions capable of square planar coordination or octahedral coordination into contact with water containing molecules to be scavenged and bringing a porous solid into contact with water containing molecules to be scavenged. In general formula (I), one of R², R³ and R⁴ is R^y present at a position meta or para to R^x; R^x and R^y are each independently a heterocyclic substituent described below; R¹, R², R³, R⁴ and R⁵ except R^y are each independently hydrogen, a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms, or a sulfonic acid group, with the proviso that they are not simultaneously hydrogen; and in the heterocyclic substituent, R⁶ and R⁷ are each independently hydrogen or methyl and A is a 5- or 6-membered heterocyclic group containing at least one nitrogen atom.

Description

Water purification method, water purification device, and water purification set

The present invention relates to a water purification method, a water purification device, and a water purification set.

Conventionally, various studies have been made on water purification methods for reducing the concentration of impurities in water. An example of an impurity is perchlorate.
Perchlorate is a substance that damages the thyroid gland that controls metabolic effects in adults and promotes physical development in children. In recent years, cases in which high concentrations of perchlorate ions have been detected in soil and water have been reported one after another. In addition, perchlorate ion (ClO ₄ ⁻ ) exhibits high solubility in water, and since it hardly interacts with the cation among all the anions, it is difficult to remove from the aqueous solution as a precipitate or the like. Ion.
As a technique for removing perchlorate from waste liquid contaminated with perchlorate (or perchlorate ions), perchlorate is concentrated, and KCl is added to the concentrated perchlorate solution to perchlorate. A method is known in which acid potassium (KClO ₄ ) is produced, cooled and crystallized (see, for example, Japanese Patent Publication No. 9-504472). Further, a water treatment system for removing perchlorate using a resin (for example, Japanese Patent Application Laid-Open No. 2004-346299 and “NEDO Overseas Report, No. 946, December 15, 2004” [searched on February 19, 2008] The Internet <http://www.nedo.go.jp/kankobutsu/report/946/946-07.pdf>") is also known.
On the other hand, compounds capable of forming capsules so as to take in various ions are known (see, for example, J. Am. Chem. Soc., 2003, Vol. 125, No. 28, p. 8595-8613). This compound has a structure that easily forms a capsule skeleton regardless of the type of ions or the size of ions taken into the capsule.

However, the above-mentioned method for producing potassium chlorate from perchlorate and crystallizing it has a concentration step of evaporating the solvent from the solution, so that the perchlorate ions in the solution are retained while maintaining the state of the solution. It cannot be captured. In addition, the above-described method of removing perchlorate using a resin has a problem of poor selectivity in terms of perchlorate ion trapping as well as costly regeneration of the resin.
On the other hand, even if an attempt is made to remove perchlorate ions using a compound capable of forming the capsule, perchlorate ions cannot be selectively captured from a system in which a plurality of anions are present.
Therefore, it is necessary to develop a purification method that selectively captures specific molecules such as perchlorate ions and reduces the concentration of the captured molecules in water.

The present invention has been made in view of the above, and an object of the present invention is to provide a water purification method, a water purification device, and a water purification set capable of purifying water with few trapped molecules.

Means for solving the above-mentioned problems are as follows.
<1> Contacting a compound represented by the following general formula (I) and a capture agent containing a metal ion capable of planar tetracoordination or regular octahedral coordination with water containing a molecule to be captured, and porous A method for purifying water, comprising bringing a solid material into contact with water containing a molecule to be captured having a molecular size of 1 nm or less.

 

^Wherein, R 2, ^{R 3,} and one of ^{R 4} is in the meta or para to ^{R x R y, R x} and ^{R y} are following heterocyclic independently of one another Represents a substituent,

Of R ¹ , R ² , R ³ , R ⁴ and R ⁵ , the remainder excluding R ^y is independently a hydrogen atom, a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms, or a sulfonic acid Represents a group, but is not simultaneously a hydrogen atom. Among the heterocyclic substituents, R ⁶ and R ⁷ each independently represent a hydrogen atom or a methyl group, and A contains at least one nitrogen atom. Represents a 5-membered or 6-membered heterocyclic group. ]

<2> The water purification method according to <1>, wherein the molecule to be trapped has a molecular size of 1 nm or less.
<3> The method for purifying water according to <1>, wherein the water after contact with the scavenger is brought into contact with the porous solid.
<4> The water purification method according to <1>, wherein the porous solid is at least one selected from the group consisting of activated carbon, zeolite, ion exchange resin, clay, and silica gel.
<5> The method for purifying water according to <1>, wherein, in the general formula (I), R ^y is in a para position with respect to R ^x .
<6> The water purification method according to <1>, wherein in the general formula (I), R ⁶ and R ⁷ are both hydrogen atoms.

<7> In the general formula (I), R ³ is R ^y , and R ¹ , R ² , R ⁴ and R ⁵ are each independently a substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms. The method for purifying water according to <1>, wherein A is an imidazolyl group.
<8> In the general formula (I), R ³ is R ^y , and R ¹ , R ² , R ⁴ and R ⁵ are each independently a substituted or unsubstituted hydrocarbon group having 1 to 6 carbon atoms. The method for purifying water according to <1>, wherein A is an imidazolyl group.
<9> In the general formula (I), R ³ is R ^y , and R ¹ , R ² , R ^4, and R ⁵ are each independently a substituted or unsubstituted hydrocarbon group having 1 or 2 carbon atoms. The method for purifying water according to <1>, wherein A is an imidazolyl group.
<10> The water purification method according to <1>, wherein the scavenger is a coordination compound including a compound represented by the general formula (I) and a metal ion capable of planar tetracoordination or regular octahedral coordination. is there.

<11> A water purification apparatus comprising a filtration part containing a compound represented by the following general formula (I) and a metal ion capable of planar tetracoordination or regular octahedral coordination, and a porous solid: It is.

^Wherein, R 2, ^{R 3,} and one of ^{R 4} is in the meta or para to ^{R x R y, R x} and ^{R y} are following heterocyclic independently of one another Represents a substituent,

Of R ¹ , R ² , R ³ , R ⁴ and R ⁵ , the remainder excluding R ^y is independently a hydrogen atom, a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms, or a sulfonic acid Represents a group, but is not simultaneously a hydrogen atom. Among the heterocyclic substituents, R ⁶ and R ⁷ each independently represent a hydrogen atom or a methyl group, and A contains at least one nitrogen atom. Represents a 5-membered or 6-membered heterocyclic group. ]

<12> The water purifier according to <11>, wherein the filtration unit includes a capturing unit including the capturing agent and an adsorption unit connected to the capturing unit and including the porous solid.

<13> A water purification set comprising a compound represented by the following general formula (I) and a scavenger containing a metal ion capable of planar tetracoordination or regular octahedral coordination, and a porous solid.

^Wherein, R 2, ^{R 3,} and one of ^{R 4} is in the meta or para to ^{R x R y, R x} and ^{R y} are following heterocyclic independently of one another Represents a substituent,

Of R ¹ , R ² , R ³ , R ⁴ and R ⁵ , the remainder excluding R ^y is independently a hydrogen atom, a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms, or a sulfonic acid Represents a group, but is not simultaneously a hydrogen atom. Among the heterocyclic substituents, R ⁶ and R ⁷ each independently represent a hydrogen atom or a methyl group, and A contains at least one nitrogen atom. Represents a 5-membered or 6-membered heterocyclic group. ]

According to the present invention, it is possible to provide a water purification method, a water purification device, and a water purification set that can purify water with few molecules to be trapped.

It is a conceptual diagram which shows an example of the water purification apparatus which concerns on this invention. It is a conceptual diagram which shows another example of the water purification apparatus which concerns on this invention. FIG. 4 is a diagram showing a state in which one capture capsule type molecule according to a reference example of the present invention includes one perchlorate ion (ClO ₄ ⁻ ) molecule, ignoring the atomic radius. It is the figure which represented the mode that one capture capsule type molecule concerning a reference example of the present invention encapsulates one molecule of perchlorate ion (ClO ₄ ⁻ ) in consideration of the van der Waals radius. It is a figure which shows the two-dimensional sheet type | mold structure (A-layer) of the coordination compound which concerns on the reference example of this invention. It is a figure which shows the two-dimensional sheet type structure (B layer) of the coordination compound which concerns on the reference example of this invention. It is a figure which shows the three-dimensional structure of the coordination compound which concerns on the reference example of this invention.

≪Water purification method≫
The water purification method of the present invention comprises a scavenger containing a compound represented by the following general formula (I) and a metal ion capable of planar tetracoordination or regular octahedral coordination, and water containing a molecule to be captured. And contacting the porous solid with water containing the molecule to be captured.
In the present invention, when the scavenger and water containing the molecule to be captured come into contact, as described later, one molecule to be captured is composed of four compounds represented by the general formula (I) and two metal ions. A trapped capsule molecule with an enclosed structure is formed. Further, when the porous solid comes into contact with water containing the molecule to be captured, the molecule to be captured and the capture capsule type molecule are adsorbed to the porous solid.
As described above, according to the method for purifying water of the present invention, the concentration of molecules to be captured in water can be effectively reduced, and the water can be purified to have few molecules to be captured.

The molecule to be captured is not particularly limited as long as it is a molecule that can be captured by the capturing agent. However, from the viewpoint of obtaining the above effect more effectively, the molecule to be captured is preferably a molecule having a molecular size of 1 nm or less.
In the present invention, the molecular size of 1 nm or less means that the maximum diameter of the molecule is 1 nm or less.
Here, the maximum diameter of a molecule refers to a value obtained from the average of the longest distances between the atoms at the ends constituting the molecule based on a structural model prepared in consideration of the van der Waals radius.
The “molecule” in the present invention may be any of a cation, an anion, and a neutral molecule.

Specific examples of the molecules to be captured in the present invention are shown below.
As anions, perchlorate ion (ClO ₄ ⁻ ), trifluoromethanesulfonate ion (CF ₃ SO ₃ ⁻ ), tetrafluoroborate ion (BF ₄ ⁻ ), azide ion (N ₃ ⁻ ), phosphate ion (PO ₄ ^3- ), and the like.
Examples of neutral molecules include benzene, toluene, xylene, cyclohexane, and cyclohexene.

Among the above specific examples, perchlorate ion (ClO ₄ ⁻ ), trifluoromethanesulfonate ion (CF ₃ SO ₃ ⁻ ), and tetrafluoroborate ion (BF ₄ ⁻ ) are preferable from the viewpoint of removal efficiency.

Further, the “water containing a molecule to be captured” in the present invention may contain other components as long as the molecule to be captured is contained in water.
“Water containing molecules to be trapped” includes, for example, drinking water, industrial water, waste water, and various aqueous solutions, colloidal solutions (milk, etc.), suspensions containing food, soil, and the like.

<Capturing agent>
The scavenger in the present invention contains a compound represented by the following general formula (I) and a metal ion capable of planar tetracoordinate or regular octahedral coordination.
Examples of the form of the scavenger in the present invention include a form of a coordination compound containing the compound represented by the general formula (I) and the metal ion, and a form of a mixture containing the coordination compound and other components.
As another form of the scavenger in the present invention, a compound represented by the general formula (I) that exists independently (that is, does not take the form of the coordination compound) and a metal containing the metal ion And a salt form.
Hereinafter, the compound represented by the general formula (I) will be described, and subsequently, a metal ion, a coordination compound, and a metal salt that can be planar tetracoordinated or octahedrally coordinated will be described.

~ Compounds represented by general formula (I) ~

^Wherein, R 2, ^{R 3,} and one of ^{R 4} is in the meta or para to ^{R x R y,} independently ^{R x} and ^{R y} are each heterocyclic-substituted below Represents a group,

Of R ¹ , R ² , R ³ , R ⁴ and R ⁵ , the remainder excluding R ^y is independently a hydrogen atom, a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms, or a sulfonic acid Represents a group, but not simultaneously a hydrogen atom,
Among the heterocyclic substituents, R ⁶ and R ⁷ each independently represent a hydrogen atom or a methyl group, and A represents a 5-membered or 6-membered heterocyclic group containing at least one nitrogen atom.

When the compound represented by the general formula (I) contacts a metal ion capable of planar tetracoordinate or octahedral coordination with a molecule to be captured in a liquid sample, a plurality of the compounds are collected together with the metal ion. The molecules are taken in to form capsule molecules (self-assembly reaction; see, for example, FIGS. 3 and 4 described later). Specific examples of the molecules to be captured are as described above.
In the present invention, a capsule molecule incorporating a molecule to be captured is referred to as a “captured capsule molecule”.
In addition to trapping and capturing one molecule to be captured, the capture capsule type molecule can also capture the captured molecule by coordination bond outside the capture capsule type molecule (two metal ions). Therefore, one molecule of the capture capsule type molecule can capture three molecules to be captured. Furthermore, it has been confirmed that one capture capsule type molecule captures another molecule to be captured with another capture capsule type molecule in addition to three molecules to be captured. That is, it is known that one capture capsule type molecule can capture up to four molecules to be captured.
The above forms can be confirmed by, for example, single crystal structure analysis and visible / ultraviolet spectrum.

Since the self-assembly reaction by the compound represented by the general formula (I) shows extremely high selectivity for the molecule to be captured, when the molecule to be captured is present in the liquid, it is efficiently and reliably captured. A molecule can be captured.
In addition, when the compound represented by the general formula (I) is in contact with the metal ion and an anion other than the molecule to be captured, it is not such a capture capsule type molecule but a coordination compound described later. Such a polymer structure is easily formed.

In the general formula (I), the viewpoint that R ^y is in the para position with respect to R ^x , that is, R ³ is R ^y , does not leave the trapped molecule and forms a capture space without a gap. Therefore, it is preferable.
In addition, it is preferable that R ^y and R ^x are the same heterocyclic substituent from the viewpoint of being able to limit the number of isomers of the captured capsule type molecule to be generated and easily identifying the product.
In R ^x and R ^y , R ⁶ and R ⁷ are preferably both hydrogen atoms from the viewpoint of forming a trapped capsule molecule without causing steric hindrance with other substituents of the aromatic ring.

Of R ¹ , R ² , R ³ , R ⁴ and R ⁵ , the remainder excluding R ^y is independently a hydrogen atom, a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms, or a sulfonic acid Represents a group but is not simultaneously a hydrogen atom. R ¹ and R ² may be bonded to each other to form a ring (aromatic ring or aliphatic ring). R ⁴ and R ⁵ may also be bonded to each other to form a ring (aromatic ring or aliphatic ring).
Of R ¹ , R ² , R ³ , R ⁴ and R ⁵ , the remainder excluding R ^y is preferably a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms.
As the number of carbon atoms of the hydrocarbon group represented by R ¹ , R ² , R ³ , R ⁴ and R ⁵ , the compound represented by the general formula (I) is sterically hindered from the viewpoint of ease of synthesis. 1 to 10 is preferable, 1 to 6 is more preferable, and 1 to 2 is particularly preferable from the viewpoint of forming a capsule without becoming and preventing anion from leaving the capsule.
Examples of the substituent that can be substituted on the hydrocarbon group include a halogen atom, a sulfonic acid group, a nitro group, a hydroxyl group, and an alkyl halide group. From the viewpoint of ease of synthesis, stability, and insolubility in water. Therefore, a fluorine atom or a perfluoroalkyl group is preferable.

In R ^x and R ^y , the heterocyclic group represented by A may be substituted with a substituent such as an alkyl group having 1 to 6 carbon atoms or a sulfonic acid group. The heterocyclic group may contain an oxygen atom or a sulfur atom in addition to the nitrogen atom.
Examples of the heterocyclic group represented by A include a heterocyclic group capable of coordinating with the metal ion. Such heterocyclic groups include pyrrolyl groups other than pyrrol-1-yl groups, 2H-pyrrolyl groups other than 2H-pyrrol-1-yl groups, imidazolyl groups, pyrazolyl groups, and isothiazol-1-yl groups. Isothiazolyl groups, isoxazolyl groups other than isoxazol-1-yl groups, pyrrolidinyl groups other than pyrrolidin-1-yl groups, imidazolidinyl groups, pyrazolidinyl groups, pyridyl groups other than pyridin-1-yl groups, pyrazyl groups, pyrimidinyl groups, pyridazinyl Preferred are a group, a piperidinyl group other than a piperidin-1-yl group, a piperazinyl group, a morpholinyl group other than a morpholin-4-yl group, and a group represented by the following structural formula.

Among these, from the viewpoint of ease of synthesis and coordination with metal ions, pyrrolyl groups other than pyrrol-1-yl groups, imidazolyl groups, pyridyl groups other than pyridin-1-yl groups, represented by the following structural formula More preferred are the groups

Of these, the imidazolyl group is particularly preferable.

The particularly preferred form of the compound represented by the general formula (I) is R from the viewpoint of ease of synthesis, prevention of formation of isomers, and formation of a capsule space that does not release the trapped molecule. ³ is R ^y , and R ¹ , R ² , R ⁴ and R ⁵ each independently has 1 to 10 carbon atoms (more preferably 1 to 6 carbon atoms, more preferably 1 or 2 carbon atoms). A substituted (more preferably halogen-substituted) or unsubstituted hydrocarbon group in which A is an imidazolyl group.

The compound represented by the general formula (I) includes the following general compounds from the viewpoint of ease of synthesis, prevention of isomer formation, and formation of a capsule space that does not release the trapped molecule. A compound represented by the formula (II) is also preferable.

 

In the general formula (II), R ¹ , R ² , R ⁴ , and R ⁵ are the matters described above for R ¹ , R ² , R ⁴ , and R ⁵ in the general formula (I) except that R ^y is not R ^y . Can be applied as is.
In the general formula (II), A ¹ has the same meaning as A in formula (I), and preferred ranges are also the same.

The compound of the present invention includes, for example, reacting a halogen-substituted aromatic compound with a compound corresponding to A in the general formula (I) in the presence of an alkali metal salt to replace the halogen atom with A. Can be easily synthesized. For example, 1,4-bis (imidazol-1-yl-methyl) benzene can be synthesized by heating and reacting imidazole and α, α'-dibromo-p-xylene in the presence of sodium hydride. Examples of such a synthesis method include C.-H. Zhou, R.-G. Xie, and H.-M. Zhao, Organic. Preparations and Procedures Int., 1996, 28 (3), 345 Has been.

Hereinafter, exemplary compounds (exemplary compounds (a) to (h)) of the compound represented by the general formula (I) are shown. However, the present invention is not limited to these.

Of the exemplified compounds (a) to (h), the exemplified compound (a) or the exemplified compound (b) is more preferable.

-Metal ions capable of planar tetracoordinate or octahedral coordination-
Examples of the metal ion capable of planar tetracoordinate or octahedral coordination in the present invention include Zn ²⁺ , Cu ²⁺ , Ni ²⁺ , Co ²⁺ , Fe ²⁺ , Mn ²⁺ , Ag ⁺ , Pd ²⁺ , and Pt ^2+. It is done.
Among these, Zn ²⁺ , Cu ²⁺ , Ni ²⁺ , Pd ²⁺ , and Pt ²⁺ are preferable, and Cu ²⁺ is particularly preferable from the viewpoint of the formation of trapping capsule type molecules and the formation of coordination compounds.

~ Coordination compounds ~
The coordination compound in the present invention is a compound containing the compound represented by the aforementioned general formula (I) and the aforementioned metal ion.

When the coordination compound is brought into contact with the trapped molecule in a liquid sample, the compound represented by the general formula (I) and the metal ion constituting the coordination compound capture the trapped molecule. Reconstituted into capsule-type molecules.
For this reason, like the case where the compound represented by the general formula (I) is used as a simple substance, the molecule to be captured can be captured with high selectivity.

As a specific structure of the coordination compound of the present invention, a polymer complex in which a plurality of compounds represented by the general formula (I) are coordinated with each of a plurality of metal ions contained in the coordination compound. Structure is mentioned.
Examples of the structure of the polymer complex include a two-dimensional sheet structure in which four molecules of the compound represented by the general formula (I) are coordinated with each metal ion. In the two-dimensional sheet type structure, the compound represented by each general formula (I) is arranged between two metal ions, and is coordinated to one metal ion at a nitrogen atom portion in one heterocyclic ring. And is coordinated to the other metal ion at the nitrogen atom in the other heterocyclic ring (see, for example, FIGS. 5 and 6 described later).
The coordination compound of the present invention may contain an anion other than a water molecule and the trapped molecule, and these water molecule and anion may be coordinated to the metal ion, It may not be coordinated to the metal ion.

In the coordination compound having the two-dimensional sheet structure, an example in which an anion is coordinated to a metal ion is, for example, “A layer” in FIG. 5 described later.
Moreover, in the coordination compound having the two-dimensional sheet structure, examples of water molecules coordinated to metal ions include “B layer” in FIG. 6 to be described later.

Moreover, when the structure of the coordination compound is the two-dimensional sheet type structure containing the anion, the anion in the two-dimensional sheet type structure is (1) a metal ion in another two-dimensional sheet type structure. Or (2) hydrogen bonds to water molecules coordinated to metal ions in another two-dimensional sheet type structure. In the cases of (1) and (2), the structure of the coordination compound is a three-dimensional structure in which a plurality of two-dimensional sheet-type structures are stacked (for example, see FIG. 7 described later).
As another example of the three-dimensional structure, two-dimensional sheet-type structures in which water molecules are coordinated to metal ions (for example, “B layer” in FIG. 6 described later) are anions (for example, sulfate ions). ) May also be included. In this structure, water molecules in the two-dimensional sheet type structure interact with water molecules in another two-dimensional sheet type structure via anions.

The structure of the coordination compound described above has been clarified by, for example, elemental analysis or single crystal structure analysis.

Examples of anions other than the trapped molecule that may be contained in the coordination compound of the present invention include OH ⁻ , SO ₄ ²⁻ , CO ₃ ²⁻ , NO ₃ ⁻ , CH ₃ COO ⁻ , C ₂ O ₄ ²⁻ , HCOO ⁻ , Cl ⁻ , Br ⁻ , F ⁻ , PF ₆ ⁻ , acetylacetonato (C ₅ H ₇ O ₂ ⁻ ), SiF ₆ ²⁻ , and the like.
Among these, NO ₃ ⁻ , SO ₄ ²⁻ , OH ⁻ , and CO ₃ ²⁻ are preferable, and SO ₄ ²⁻ is more preferable from the viewpoint of the formation of coordination compounds.

As a method for synthesizing the coordination compound of the present invention, the metal ion (component A) and the compound represented by the general formula (I) (component B) have a molar ratio [component A / component B] of 1. The method of making it react in the ratio used as / 2 is mentioned.

As a method of reacting the A component and the B component, a metal salt composed of the A component and an anion other than the molecule to be trapped (specific examples are as described above) is used as a solvent (for example, water, dimethyl ester). Formamide, methanol, ethanol, propanol, acetonitrile, acetone, etc.) are dissolved in solution A, and component B is dissolved in another solvent (eg, dimethylformamide, methanol, ethanol, propanol, acetonitrile, acetone, etc.). There is a method in which the solution B is dissolved and the solution A and the solution B are mixed and reacted.

Further, the component A and the component B may be dissolved and reacted in the same solvent. In this case, a single solvent such as methanol, dimethylformamide, or ethanol may be used as the solvent. In addition, a mixed solvent such as water / acetonitrile, water / dimethylformamide, water / methanol, water / ethanol, methanol / dimethylformamide, ethanol / dimethylformamide or the like may be used.

~ Metal salt ~
The scavenger in the present invention includes a compound represented by the general formula (I) that exists independently (does not take the form of a coordination compound), and a metal salt, in addition to the form containing the coordination compound. It may be in the form of a mixture.
Here, as the metal salt, the above-mentioned “metal salt composed of the component A and an anion other than the trapped molecule” can be used.

<Porous solid>
Specific examples of the porous solid in the present invention include activated carbon, zeolite, ion exchange resin (cation exchange resin or anion exchange resin), clay (clay), silica gel, glass fiber, nonwoven fabric, filter paper, and the like. Among these, activated carbon, zeolite, ion exchange resin, clay (clay), and silica gel are preferable, and activated carbon, zeolite, ion exchange resin, and clay (clay) are more preferable.

Examples of the activated carbon include crushed activated carbon, granular activated carbon, and powdered activated carbon. Among them, granular activated carbon and crushed activated carbon are preferable, and crushed activated carbon is more preferable from the viewpoint of the passing speed of the aqueous solution to be treated. preferable.

Natural zeolite and synthetic zeolite can be used as the zeolite.
For example, zeolite 3A, zeolite 4A, zeolite 5A, and zeolite 13X can be mentioned. Among them, zeolite 5A and zeolite 13X are preferable, and zeolite 13X is more preferable.

Examples of the anion exchange resin include acrylic anion exchange resins, styrene anion exchange resins, and dimethylamine anion exchange resins. Among them, styrene anion exchange resins and dimethylamine type An anion exchange resin is preferred, and a dimethylamine anion exchange resin is more preferred.

Examples of the cation exchange resin include styrene cation exchange resins, methacrylic acid cation exchange resins, and acrylic acid cation exchange resins. Among them, methacrylic acid cation exchange resins are preferable.

The pore size of the porous solid in the present invention is not particularly limited, but is preferably 0.4 nm to 1.5 nm, particularly preferably 0.6 nm to 1.0 nm, from the viewpoint of adsorptivity depending on the size of the molecule to be captured.

In the present invention, the method of bringing the capturing agent into contact with water containing the molecule to be captured may be a method of adding a capturing agent to the water containing the molecule to be captured or a method of passing water containing the molecule to be captured through the capturing agent. .
In the present invention, the method of bringing the porous solid into contact with the water containing the molecule to be trapped is the method of adding the porous solid to the water containing the molecule to be trapped. The method of letting it pass may be used.

In the present invention, the capturing agent and water containing the molecule to be captured (hereinafter, “water containing the molecule to be captured” is also simply referred to as “liquid sample”) are contacted (hereinafter also referred to as “treatment A”). Further, contacting the porous solid and water containing the molecule to be captured (hereinafter, also referred to as “treatment B”) may be performed simultaneously or separately.

In the present invention, the form in which the treatment A and the treatment B are simultaneously performed is a form in which the capture agent and the porous solid are added to a liquid sample (independently or as a mixture), Examples include a form in which a liquid sample is passed through a mixture containing a capture agent and the porous solid.

In the present invention, the form in which the process A and the process B are separately performed includes a form in which the process A is performed in the order of the process B and a form in which the process B is performed in the order of the process A.
From the viewpoint of more effectively reducing the concentration of the molecule to be captured, the form in which the process A and the process B are performed independently is the form in which the process A is performed in the order of the process B out of the two forms (that is, the capture agent). The liquid sample after contact with the porous solid is preferably brought into contact with the porous solid.
Moreover, by performing in order from the process A to the process B, not only the density | concentration of a to-be-captured molecule | numerator but the density | concentration of a metal ion can be reduced.

As a specific example of the form of processing A to process B, the liquid sample is passed through a capture agent (process A), and the liquid sample that has passed through the capture agent is further passed through a porous solid (process B). Is preferred. In the case of this form, you may combine with other filtration as needed.
As another specific example of the form performed in the order of processing A to processing B, a capturing agent is added to the liquid sample (processing A), and the unreacted capturing agent is filtered from the liquid sample to which the capturing agent is added. Examples include a form in which a porous solid is added to the liquid sample that has been removed and the capture agent has been removed (Process A).

In the present invention, the time for contacting the scavenger and water containing the molecule to be captured is not particularly limited, but is preferably 2 hours or longer, more preferably 6 hours or longer, and particularly preferably 10 hours or longer. The upper limit is not particularly limited, but is, for example, 30 hours.
In the present invention, the time for contacting the porous solid with water containing the molecule to be trapped is not particularly limited, and is preferably 2 hours or more, more preferably 6 hours or more, and more preferably 10 hours, although it depends on the kind of the porous solid. The above is particularly preferable. The upper limit is not particularly limited, but is, for example, 30 hours.

In the treatment A, from the viewpoint of increasing the contact frequency between the compound represented by the general formula (I), the metal ion, and the molecule to be captured and improving the reactivity of the capture capsule type molecule formation reaction, the liquid sample is heated. May be. The heating temperature varies depending on the type of metal salt, the type of compound represented by formula (I), the type of coordination compound, etc., but is preferably 0 to 100 ° C., more preferably 20 to 70 ° C. .
The temperature of the liquid sample in the treatment B varies depending on the kind of the porous solid and the like, but is preferably 5 to 40 ° C., more preferably 20 to 30 ° C. from the viewpoint of adsorptivity.

As mentioned above, although the preferable form of the water purification method of this invention was demonstrated, in addition to the said process A and the said process B, the water purification method of this invention performs other processes, such as a pre-process, a middle process, a post-process. May be included.
As an example of the pretreatment, for example, when a liquid sample shows acidity or alkalinity, the liquid sample is passed through a buffer (or a buffer is added to the liquid sample), so that the liquid sample A process to bring it close to sex. By this process, in particular, the efficiency in the process A is further improved. Here, examples of the buffer include soil.
Examples of the post-treatment include filtration with a known filter.

≪Water purification device≫
The water purification apparatus of the present invention comprises a filtration unit comprising a compound represented by the general formula (I) and a scavenger containing a metal ion capable of planar tetracoordinate or regular octahedral coordination, and a porous solid. Prepare.
According to the water purification apparatus of the present invention, the scavenger and the water containing the molecule to be trapped can be brought into contact, and furthermore, the porous solid and the water containing the molecule to be trapped can be brought into contact with each other. The concentration of trapped molecules in water can be effectively reduced.

Hereinafter, an example of the water purification apparatus of the present invention will be described with reference to FIG.
In FIG. 1, the water purification device 10 has a filtration unit 12 including a scavenger 14 and a porous solid 16. The filtration unit 12 has a supply port 22 and a discharge port 24, and the flow rate adjusting unit 18 is connected to the discharge port 24.
Further, a filter 15 is provided on the downstream side of the capture agent 14 (the discharge port 24 side, hereinafter the same), and a filter 17 is provided on the downstream side of the porous solid 16.
The arrangement of the capture agent 14 and the porous solid 16 is the capture agent 14 on the upstream side (the supply port 22 side, hereinafter the same), and the porous solid 16 on the downstream side.

Next, the case where the purification process of a liquid sample (namely, water containing a trapped molecule) is performed using the water purification apparatus 10 will be described.
First, a liquid sample is supplied to the filtration part 12 from the direction of arrow I, and the supplied liquid sample contacts the capture agent 14 in the filtration part 12 (the processing A). As a result, the molecule to be captured in the liquid sample is captured by the capture agent 14 (that is, a capture capsule type molecule is formed).
Next, the liquid sample passes through the filter 15 and comes into contact with the porous solid 16 (process B). Thereby, a small amount of molecules to be captured that cannot be captured by the capturing agent are adsorbed to the porous solid 16. On the other hand, the trapped capsule molecules formed as described above are also adsorbed to the porous solid 16.
The liquid sample after the above purification treatment passes through the filter 17, the discharge port 24 and the flow rate adjustment unit 18 and is discharged in the direction of the arrow O.

In the above purification treatment, the contact time between the liquid sample and the capture agent 14 and the contact time between the liquid sample and the porous solid 16 can be collectively adjusted by the flow rate adjusting unit 18.
A preferable range of the contact time is as described above.
For example, it is preferable to adjust the flow rate by the flow rate adjusting unit 18 in accordance with the side of the capturing agent 14 and the porous solid 16 that requires a longer contact time.
As the flow rate adjustment unit 18, known means such as an operation valve and an adjustment valve can be used.

Specific examples of the structure of the filtration unit 12 include a structure in which the capture agent 14 and the porous solid 16 are placed in a hollow container. Here, there is no limitation in particular as a hollow container, For example, a well-known column, a filter housing, etc. can be used.
The amount of the scavenger 14 is not particularly limited. For example, when treating 100 l of water containing 100 ppm of molecules to be captured, 50 g or more is preferable, and 100 g or more is more preferable. The upper limit is not particularly limited, but is, for example, 500 g.
Further, the amount of the porous solid 16 is not particularly limited. For example, when 100 l of water containing 100 ppm of molecules to be captured is treated, 50 g or more is preferable, and 100 g or more is more preferable. The upper limit is not particularly limited, but is, for example, 500 g.

Moreover, a well-known filter can be used as the filter 15 and the filter 17 provided in the downstream of the capture | acquisition agent 14 and the downstream of the porous solid 16 in a hollow container. Note that at least one of these filters may be omitted.
Further, the water purification device 10 is not limited to the form in which the capture agent 14 and the porous solid 16 are directly put into the hollow container, and the cartridge containing the capture agent 14 and the cartridge containing the porous solid 16 are mounted in the hollow container. It may be a form to do.

In FIG. 1, the trapping agent 14 (that is, the trapping portion) on the upstream side and the porous solid 16 (that is, the adsorbing portion) on the downstream side are divided into two filtration portions. 14 and the porous solid 16 may be mixed to constitute one filtration unit.
However, from the viewpoint of further reducing the concentration of molecules to be captured, it is more preferable to dispose a capturing agent 14 as a capturing part upstream and a porous solid 16 as an adsorbing part downstream as shown in FIG. .

Further, a flow rate adjusting unit may be provided on the upstream side of the filtering unit 12 in the liquid sample flow path so that the supply rate of the liquid sample can be adjusted.

As mentioned above, although the form which puts the capture | acquisition agent 14 and the porous solid 16 together in one hollow container was demonstrated, as shown in FIG. 2, other capture | acquisition agent 14 and the porous solid 16 are put into another hollow container. An example is also suitable.
In FIG. 2, the water purification device 30 includes a capturing unit 32 having the capturing agent 14 and an adsorption unit 42 including the porous solid 16. The capturing unit 32 and the adsorbing unit 42 constitute a filtering unit. As the specific structures of the capturing unit 32 and the adsorbing unit 42, the matters described for the filtering unit 12 in the water purifier 30 can be applied as they are. The preferred amounts of the scavenger 14 and the porous solid 16 are the same as in the case of the water purification device 10.
The capturing unit 32 has a supply port 36 and a discharge port 37. A filter 35 is provided on the downstream side of the capture agent 14 (on the discharge port 37 side, the same applies hereinafter). The filter 35 can be omitted.
The adsorbing part 42 has a supply port 46 and a discharge port 47, and a filter 45 is provided on the downstream side of the porous solid 16 (the discharge port 47 side, the same applies hereinafter). The filter 45 can be omitted.
The discharge port 37 of the capturing unit 32 and the supply port 46 of the suction unit 42 are connected by a connection unit 40. The connection unit 40 may have a flow rate adjusting function as will be described later.
A flow rate adjusting unit 50 is connected to the discharge port 47 of the adsorption unit 42.

Even when the water purification device 30 is used, water (liquid sample) can be purified as in the case of using the water purification device 10 described above.
That is, a liquid sample is supplied to the capturing unit 32 from the direction of the arrow I, and the supplied liquid sample contacts the capturing agent 14 in the capturing unit 32 (Processing A). As a result, the molecule to be captured in the liquid sample is captured by the capture agent 14 (that is, a capture capsule type molecule is formed).
The liquid sample after contacting the capture agent 14 is transferred to the adsorption unit 42 through the filter 35, the discharge port 37, the connection unit 40, and the supply port 46.
The transferred liquid sample comes into contact with the porous solid 16 (Process B). Thereby, a small amount of molecules to be captured that cannot be captured by the capturing agent are adsorbed to the porous solid 16. On the other hand, the trapped capsule molecules formed as described above are also adsorbed to the porous solid 16.
The liquid sample after the above purification treatment passes through the filter 45, the discharge port 47, and the flow rate adjustment unit 50, and is discharged in the direction of the arrow O.

In the water purification device 30, the contact time between the liquid sample and the capture agent 14 and the contact time between the liquid sample and the porous solid 16 can be collectively adjusted by the flow rate adjusting unit 50.
A preferable range of the contact time is as described above.
For example, it is preferable to adjust the flow rate by the flow rate adjusting unit 50 in accordance with the side of the capturing agent 14 and the porous solid 16 that requires a longer contact time.
As the flow rate adjusting unit 50, known means such as an operation valve and an adjusting valve can be used.

Moreover, in the water purification apparatus 30, the means similar to the flow volume control part 50 can also be provided in another location.
For example, by providing a flow rate adjusting unit between the capturing unit 32 and the adsorbing unit 42 in the flow path of the liquid sample, the contact time between the liquid sample and the capturing agent 14 and the contact between the liquid sample and the porous solid 16. The time can be adjusted independently.
The term “between the capture unit 32 and the adsorption unit 42 in the flow path of the liquid sample” refers to, for example, the downstream side of the capture unit 32 (for example, the vicinity of the discharge port 37) and the upstream side of the adsorption unit 42 (for example, supply) The vicinity of the mouth 46), and the like. Moreover, the connection part 40 may have a flow volume adjustment function.
In addition, a flow rate adjusting unit may be provided on the upstream side of the capturing unit 32 (for example, in the vicinity of the supply port 36) in the liquid sample flow path so that the supply rate of the liquid sample can be adjusted.

Further, the connection between the capture unit 32 and the suction unit 42 is not limited to using the independent connection unit 40 shown in FIG. For example, the end part of the capture part 32 and the end part of the suction part 42 may be provided with a mutually connectable mechanism (such as a screw mechanism), and the capture part 32 and the suction part 42 may be connected by this mechanism. .

As mentioned above, although the example of the water purification apparatus of this invention was demonstrated, as long as the filtration part containing a capture | acquisition agent and porous solid is provided, the water purification apparatus of this invention is not limited to the said 2 examples. Absent. For example, a structure such as a known water purifier can be used without particular limitation.

≪Water purification set≫
The water purification set of the present invention comprises a scavenger containing a compound represented by the general formula (I) and a metal ion capable of planar tetracoordinate or octahedral coordination, and a porous solid.
The water purification method of the present invention can be performed using the water purification set.
That is, the process A can be performed using a scavenger, and the process B can be performed using a porous solid.

An advantage of using the water purification set is that the capturing agent can be easily brought into contact with the liquid sample for an arbitrary time. For example, after the capture agent is filled in a glass filter container, it is possible to perform an operation such as immersing in a liquid sample for an arbitrary time, and subsequently immersing activated carbon or an ion exchange resin in an aqueous solution for an arbitrary time.

As a specific form of the water purification set, there is a form of a set in which the scavenger and the porous solid are combined in a state where they are individually put in a container. In this form, a set in which one type of capture agent and porous solid is combined may be used, or a set including a plurality of types of capture agent and / or porous solid (that is, depending on conditions such as a molecular species to be captured). And a set in which a combination of a capturing agent and a porous solid can be selected.
In this form, the capture agent and the porous solid can be used out of the container at the time of use.

Further, as another specific form of the water purification set, a set form in which a capturing member including a capturing agent and an adsorption member including a porous solid are combined is also suitable. In this form, a set in which one type of capture member and adsorption member is combined may be used, or a set including a plurality of types of capture members and / or adsorption members (that is, capture is performed according to conditions such as the species to be captured). It may be a set in which a combination of a member and an adsorbing member can be selected.
Here, as the capturing member and the adsorbing member, members having the same structure as the capturing unit 32 and the adsorbing unit 42 described for the water purification device 30 described above can be applied.
In this embodiment, the process A can be performed using a capturing member, and the process B can be performed using an adsorption member.
Moreover, the water purifier of this invention can be obtained by connecting the said capture member and the said adsorption member. As described above, the connection may be performed using an independent connection member, or by providing a mechanism (screw mechanism or the like) that can be connected to each other at the end of the capturing means and the end of the suction means. You may go.

Examples of the present invention will be described below, but the present invention is not limited to these examples.

[Reference Example 1]
<Synthesis of Exemplary Compound (a) (1,4-bis (imidazol-1-yl-methyl) 2,3,5,6-tetramethylbenzene; bitb)>
According to the following reaction scheme 1, exemplary compounds (a) (bitb) were synthesized.
First, a THF suspension (5 ml) of 0.095 g (4 mmol) of NaH (Kanto Chemical Co., Ltd.) was slowly added to 10 ml of a THF solution of 0.33 g (5 mmol) of imidazole (Kanto Chemical Co., Ltd.). The mixture was stirred for 20 minutes (THF (tetrahydrofuran) was manufactured by Kanto Chemical Co., Inc., the same applies hereinafter).
To the stirred solution, a THF solution of 0.64 g (2 mmol) of 1,4-bisbromomethyl-2,3,5,6-tetramethylbenzene (manufactured by Tokyo Chemical Industry Co., Ltd., common name: dibromodurene) ( 15 ml) was slowly added and refluxed at 60 ° C. for 3-5 hours. The refluxed solution was cooled to room temperature, water (40 ml) was added to the cooled solution, chloroform (Kanto Chemical Co., Ltd.) was added, and the crude product was extracted with chloroform. The obtained chloroform extract was dried over anhydrous sodium sulfate. The chloroform extract after drying was concentrated and petroleum ether (manufactured by Kanto Chemical Co., Inc.) was added to obtain Exemplified Compound (a) at a yield of 53%.

The structure of the exemplified compound (a) obtained above was confirmed by NMR.
~ NMR data ~
¹ H NMR spectrum (300MHz, CDCl ₃ , rt): δ7.24 (d, 2H), 6.97 (s, 2H), 6.75 (d, 2H), 5.17 (s, 4H), 2.19 (s, 12H)

[Reference Example 2]
<Formation of trapped capsule molecules incorporating perchloric acid>
0.093 g (0.25 mmol) of copper (II) perchlorate hexahydrate (manufactured by Kishida Chemical Co., Ltd.) and 0.147 g (0. 0.1 g) of the exemplary compound (a) (bitb) obtained in Reference Example 1. 5 mmol) was added to a mixed solution of acetonitrile / water (25 ml / 25 ml) (acetonitrile was manufactured by Kanto Chemical Co., Inc.), and the mixed solution was stirred and allowed to stand for several days to obtain purple crystals.
The obtained purple crystals were collected, and the structure of the purple crystals was confirmed by single crystal structure analysis and mass spectrometry measurement.
Single crystal structure analysis was performed using a structure analysis apparatus (Mercury two-dimensional detector system) manufactured by Rigaku Corporation and collecting X-ray reflection data using a molybdenum Kα radiation source at room temperature. The structural analysis was performed using the Crystal Structure program manufactured by Rigaku Corporation.
Moreover, the mass spectrometry measurement was performed using the LCT mass spectrometer made from Micromass.

-Single crystal structure analysis data-
monoclinic space group P2 ₁ /c(No.14), a = 25.73 (2) Å, b = 13.26 (1) Å, c = 27.73 (4) Å, β = 117.52 (1) °, V = 8383 (13 ) Å ³ , Z = 4, R = 0.090, Rw = 0.223

From the single crystal structure analysis data and mass spectrometry measurement, it was found that the purple crystal was [Cu ₂ (bitb) ₄ ] (ClO ₄ ) ₄ obtained by the following reaction.

Further, the purple crystal ([Cu ₂ (bitb) ₄ ] (ClO ₄ ) ₄ ) was found to be a capture capsule type molecule from the single crystal structure analysis data and mass spectrometry measurement.
FIGS. 3 and 4 show the structure of the trapped capsule molecule, which has been clarified from the single crystal structure analysis data and the mass spectrometry measurement.

As shown in FIG. 3, the structure of the trapping capsule molecule is a structure in which a capsule skeleton formed by two copper (II) ions and four bit4 molecules encloses one molecule of perchlorate ion. Although not shown, perchlorate ions are coordinated to both copper (II) ions one molecule at a time from the outside of the capsule.
In addition, as shown in FIG. 4, the size of the space formed by two copper (II) ions and the bitb4 molecule is 6.5 ０．６ (0.65 nm) × 6.5 Å (0.65 nm) × 5.0 Å ( 0.50 nm), and was a size that contained perchlorate ions so as not to be detached.
In FIGS. 3 and 4, hydrogen atoms are omitted.

The obtained purple crystals were dissolved in any of dimethylformamide, methanol, ethanol, acetonitrile, and acetone. This result also shows that the purple crystal has the structure of a trapped capsule molecule.

[Reference Example 3]
<Synthesis of Coordination Compound (Cu-bitb Polymer) Containing Copper (II) Ion and Bitb>
The reagent was synthesized using copper sulfate pentahydrate (CuSO ₄ · 5H ₂ O) manufactured by Wako Pure Chemical Industries, Ltd. and dimethylformamide (DMF) manufactured by Kanto Chemical Co., Inc.
58.9 mg (0.2 mmol) of bitb were dissolved in 20 ml of DMF, and 25.0 mg (0.1 mmol) of copper sulfate were dissolved in 20 ml of water. Each of the obtained solutions was reacted at once and left at room temperature for 1 week to obtain water-insoluble blue crystals.
The resulting blue crystal was subjected to single crystal structure analysis.
In addition, since the blue crystal was not soluble in the solvent and could not be subjected to mass spectrometry, the ratio of carbon, hydrogen, and nitrogen in the blue crystal was confirmed by elemental analysis and matched with the single crystal structure analysis result. It was confirmed.

Elemental analysis data
Theoretical value _{(C 36 H 60 CuN 8 O} 12 S) C, 48.45; H, 6.78; N, 12.55
Found C, 48.72; H, 6.41; N, 12.73
(Measuring device Euro EA3000 manufactured by Euro Vector)

-Single crystal structure analysis data-
monoclinic space group C2 / m (No. 12), C ₃₆ H ₆₀ CuN ₈ O ₁₂ S, Mw (formula) 892.5, a = 12.3 (1) Å, b = 27.3 (2) Å, c = 13.8 (1 ) Å, β = 113.42 (1) °, V = 4252 (62) Å ³ , Z = 4, R = 0.114, Rw = 0.470

From the results of elemental analysis and single crystal structure analysis, the obtained blue crystal is not a capture capsule type molecule as in Reference Example 2, but a coordination compound ({[Cu (bitb) ₂ (H ₂ O) ₂ ] _∞ It was found to be a polymer complex represented by [Cu (bitb) ₂ (SO ₄ ) ₂ ] _∞ }; hereinafter also referred to as “Cu-bitb polymer”). The detailed structure of the coordination compound will be described later.

Further, the obtained blue crystals did not dissolve in any of water, dimethylformamide, methanol and ethanol. This result also shows that the blue crystals are not the structure of the trapped capsule molecule, but the coordination compound ({[Cu (bitb) ₂ (H ₂ O) ₂ ] _∞ [Cu (bitb) ₂ (SO ₄ ) ₂ ] _∞ } Has a structure of a polymer complex represented by
The reason why the blue crystal takes the structure of the coordination compound rather than the structure of the trapping capsule type molecule is thought to be that the size of the sulfate ion is larger than the size of the perchlorate ion. That is, since the size of the molecule that can be encapsulated by the capsule skeleton consisting of the bit4 molecule and two metal ions does not match the size of the sulfate ion, the capsule skeleton is not formed, and the coordination compound is formed.

FIGS. 5 to 7 show the structures of the coordination compounds that have been clarified from the results of elemental analysis and single crystal structure analysis.
5 and 6, the ionic species having six bonds represents a copper (II) ion, and one six-membered ring and two five-membered rings (heterocycles) arranged between two copper (II) ions. ) Represents a bitb. Here, bitb is coordinated to one copper (II) ion at the nitrogen atom in one heterocyclic ring, and coordinated to the other copper (II) ion at the nitrogen atom in the other heterocyclic ring. is doing. In addition, since the coordination compound has a structure spread in an infinite chain, in FIGS. 5 to 7, atoms and molecules located in the periphery of the figure are omitted. In FIGS. 5 to 7, hydrogen atoms are omitted.
As shown in FIGS. 5 to 7, the structure of the coordination compound is a three-dimensional structure in which two types of two-dimensional sheet-type structures (A layer shown in FIG. 5 and B layer shown in FIG. 6) are alternately stacked ( FIG. 7).
Details of each structure will be described below.

The A layer shown in FIG. 5 is a two-dimensional sheet-type structure that is formed by coordinating four molecules of bitb to one copper (II) ion and spreads in an infinite two-dimensional manner. More specifically, the A layer has a negatively charged two-dimensional sheet structure [Cu (bitb) ₂ (SO ₄ ) _{2 in} which two molecules of sulfate ions are coordinated with the copper (II) ion. ] _∞ . In FIG. 5, arrows a and b represent axes parallel to the two-dimensional plane of the A layer (hereinafter also referred to as “a axis” and “b axis”).

The B layer shown in FIG. 6 is also a two-dimensional sheet-type structure that is formed by coordinating four molecules of bitb to one copper (II) ion and spreads in an infinite two-dimensional manner. More specifically, the B layer is a positively charged two-dimensional sheet structure [Cu (bitb) ₂ (H ₂ O) in which two molecules of water are coordinated with the copper (II) ion. ₂ ] _∞ . In FIG. 6, arrows a and b represent axes parallel to the two-dimensional plane of the B layer (hereinafter also referred to as “a axis” and “b axis”).

The three-dimensional structure shown in FIG. 7 is a structure in which the A layer and the B layer are alternately stacked. In FIG. 7, an arrow c represents an axis that is not parallel to the two-dimensional plane of the A layer and the B layer.
As shown in FIG. 7, the A layer and the B layer are respectively arranged on the ab plane, and have a structure in which they are alternately stacked along the c-axis.
In FIG. 7, sulfate ions coordinated to copper (II) ions in A layer are hydrogen-bonded to water molecules coordinated to copper (II) ions in the adjacent B layer (O -O = 2.98 cm). As a result, it has a three-dimensional structure through hydrogen bonds.

[Example 1]
<Experiment on removal of perchlorate ion>
~ Sample 1 (blank) ~
Sodium perchlorate was dissolved in distilled water to prepare Sample 1 (30 ml) containing 100 ppm of perchlorate ions.
About the obtained sample 1 (blank), the density | concentration of the perchlorate ion was measured on condition of the following by ion chromatography.

-Ion chromatography measurement conditions-
The measurement was performed using an ion chromatograph IC 861 manufactured by Metrohm. The measurement was performed by a CO ₂ differential presser method, and anions were detected by an electric conductivity detector. The measurement was performed at room temperature of 23 ° C., and the sample used for the measurement was filtered through a membrane filter, and the aqueous solution used for the measurement was purified with an ultrapure water production apparatus Direct-Q manufactured by Millipore.

~ Sample 2 ~
The sample 1 is represented by the coordination compound ({[Cu (bitb) ₂ (H ₂ O) ₂ ] _∞ [Cu (bitb) ₂ (SO ₄ ) ₂ ] _∞ }) obtained in Reference Example 3. A polymer complex (hereinafter referred to as “Cu-bitb polymer”) (46 mg) was added (treatment A), and allowed to stand for 24 hours to obtain a sample 2.
About the obtained sample 2, the same measurement as the sample 1 was performed.

~ Sample 3, Sample 6, Sample 9 ~
Sample 1 above includes 50 mg of activated carbon (activated carbon manufactured by Wako Pure Chemicals, crushed 0.2 mm to 1 mm), 50 mg of ion exchange resin (weakly basic anion exchange resin WA-30 manufactured by Mitsubishi Chemical Corporation), or zeolite (Union Showa) 50 mg of Molecular Sieve 13X (manufactured by Co., Ltd.) was added (Processing B) and allowed to stand for 24 hours to obtain Sample 3, Sample 6, or Sample 9.
With respect to the obtained sample 3, sample 6, or sample 9, the same measurement as that of sample 1 was performed.

~ Sample 4, Sample 7, Sample 10 ~
In the above sample 1, 46 mg of Cu-bitb polymer, 50 mg of activated carbon (activated carbon manufactured by Wako Pure Chemicals, crushed 0.2 mm to 1 mm), 50 mg of ion exchange resin (WA-30), or 50 mg of zeolite (13X) In addition (hereinafter, this treatment is referred to as “AB simultaneous”), the sample was allowed to stand for 24 hours to obtain Sample 4, Sample 7, or Sample 10.
With respect to the obtained sample 4, sample 7, or sample 10, the same measurement as that of sample 1 was performed.

~ Sample 5, Sample 8, Sample 11 ~
46 mg of Cu-bitb polymer was added to the sample 1 and allowed to stand for 24 hours.
After leaving for 24 hours, the precipitate (unreacted Cu-bitb polymer and trapping capsule type molecule) is removed by filtration, and the filtrate is activated carbon (activated carbon manufactured by Wako Pure Chemical Industries, crushed 0.2mm-1mm) 50mg, Ion exchange resin (WA-30) 50 mg or zeolite (13X) 50 mg was added (hereinafter referred to as “A → B”) and allowed to stand for 24 hours.
About the filtrate after leaving still for 24 hours, the same measurement as sample 1 was performed.

The results are shown in Table 1.

As shown in Table 1, when treatment A with Cu-bitb polymer and treatment B with activated carbon, zeolite, or ion exchange resin were combined ("AB simultaneous" and "A → B"), only A The concentration of perchlorate ions was reduced compared to the case of B and B alone.
Further, compared with “AB simultaneous”, the concentration of perchlorate ions was further reduced in “A → B”.

[Example 2]
<Comparison of copper ion concentration>
Next, with respect to Sample 4, Sample 5, Sample 7, Sample 8, Sample 10, and Sample 11 in Example 1, the concentration of copper ions was measured under the following conditions.

-Copper ion measurement conditions (multi-type ICP emission spectrometer)-
After adding nitric acid (1%) to 20 ml of sample and thermally decomposing it, the sample is made up to 20 ml and the concentration of copper ions contained in the aqueous solution is determined using a multi-type ICP emission spectrometer (ICP (VISTA-MPX manufactured by Varian). )).

Next, the copper ion concentration in the case of “AB simultaneous” and the copper ion concentration in the case of “A → B” were compared.
As a result, when the copper ion concentration of Sample 4 (simultaneously AB) was 100, the copper ion concentration of Sample 5 (A → B) was 13.9. Further, when the copper ion concentration of sample 7 (simultaneous with AB) was 100, the copper ion concentration of sample 8 (A → B) was 45.9. When the copper ion concentration of sample 10 (simultaneous with AB) was 100, the copper ion concentration of sample 11 (A → B) was 1.7.
These results are summarized in Table 2.

As shown in Table 2, compared to “AB simultaneous”, the concentration of copper ions was reduced in “A → B”.
As described above, it was confirmed from Tables 1 and 2 that the concentration of perchlorate ions was further reduced and the concentration of copper ions was also reduced in “A → B” compared to “AB simultaneous”. .

Example 3
<Experiment on Removal of Tetrafluoroborate Ion (BF ₄ ⁻ )>
Sample 101 (30 ml) containing 100 ppm of tetrafluoroborate ions was prepared by dissolving sodium tetrafluoroborate in distilled water.
In addition, the concentration (100 ppm) of tetrafluoroborate ions in the sample 101 (blank) is a value measured under the above-described conditions by ion chromatography.

-Sample 102, Sample 104, Sample 106-
In the sample 101, 46 mg of Cu-bitb polymer, 50 mg of activated carbon (activated carbon made by Wako Pure Chemicals, crushed 0.2 mm to 1 mm), 50 mg of ion exchange resin (WA-30), or 50 mg of zeolite (13X) In addition (hereinafter, this treatment is referred to as “AB simultaneous”), the sample was allowed to stand for 24 hours to obtain Sample 102, Sample 104, or Sample 106.
The obtained sample 102, sample 104, or sample 106 was measured in the same manner as the sample 101.

~ Sample 103, Sample 105, Sample 107 ~
To the sample 101, 46 mg of Cu-bitb polymer was added and allowed to stand for 24 hours.
After leaving for 24 hours, the precipitate (unreacted Cu-bitb polymer and trapping capsule type molecule) is removed by filtration, and the filtrate is activated carbon (activated carbon manufactured by Wako Pure Chemical Industries, crushed 0.2mm-1mm) 50mg, Add 50 mg of ion exchange resin (WA-30) or 50 mg of zeolite (13X) (hereinafter referred to as “A → B”) and let stand for 24 hours to give Sample 103, Sample 105, or Sample 107 was obtained.
About the filtrate after leaving still for 24 hours, the same measurement as sample 101 was performed.
The measurement results are shown in Table 3 below.

As shown in Table 3, it was confirmed that the concentration of tetrafluoroborate ions was reduced by combining treatment A with Cu-bitb polymer and treatment B with activated carbon, zeolite, or ion exchange resin.
Further, compared to “AB simultaneous”, the concentration of tetrafluoroborate ions was further reduced in “A → B”.

The disclosure of Japanese application 2008-055240 is incorporated herein by reference in its entirety.
All documents, patent applications, and technical standards mentioned in this specification are to the same extent as if each individual document, patent application, and technical standard were specifically and individually described to be incorporated by reference, Incorporated herein by reference.

Claims (13)

1. Contacting a capture agent comprising a compound represented by the following general formula (I) and a metal ion capable of planar tetracoordinate or regular octahedral coordination with water containing a molecule to be captured;
   as well as,
   Contacting a porous solid with water containing a molecule to be captured;
   Water purification method including.
   

   

   
   
   ^Wherein, R 2, ^{R 3,} and one of ^{R 4} is in the meta or para to ^{R x R y, R x} and ^{R y} are following heterocyclic independently of one another Represents a substituent,
   

   

   
   
   Of R ¹ , R ² , R ³ , R ⁴ and R ⁵ , the remainder excluding R ^y is independently a hydrogen atom, a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms, or a sulfonic acid Represents a group, but not simultaneously a hydrogen atom,
   Among the heterocyclic substituents, R ⁶ and R ⁷ each independently represent a hydrogen atom or a methyl group, and A represents a 5-membered or 6-membered heterocyclic group containing at least one nitrogen atom. ]
2. The water purification method according to claim 1, wherein the molecule size of the trapped molecule is 1 nm or less.
3. The method for purifying water according to claim 1, wherein the water after contact with the scavenger is brought into contact with the porous solid.
4. The water purification method according to claim 1, wherein the porous solid is at least one selected from the group consisting of activated carbon, zeolite, ion exchange resin, clay, and silica gel.
5. The method for purifying water according to claim 1, wherein, in the general formula (I), R ^y is in a para position with respect to R ^x .
6. The method for purifying water according to claim 1, wherein, in the general formula (I), both R ⁶ and R ⁷ are hydrogen atoms.
7. In the general formula (I), R ³ is R ^y , and R ¹ , R ² , R ⁴ and R ⁵ are each independently a substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms, The method for purifying water according to claim 1, wherein A is an imidazolyl group.
8. In the general formula (I), R ³ is R ^y , and R ¹ , R ² , R ⁴ and R ⁵ are each independently a substituted or unsubstituted hydrocarbon group having 1 to 6 carbon atoms, The method for purifying water according to claim 1, wherein A is an imidazolyl group.
9. In the general formula (I), R ³ is R ^y , and R ¹ , R ² , R ^4, and R ⁵ are each independently a substituted or unsubstituted hydrocarbon group having 1 or 2 carbon atoms, The method for purifying water according to claim 1, wherein A is an imidazolyl group.
10. The method for purifying water according to claim 1, wherein the scavenger is a coordination compound comprising a compound represented by the general formula (I) and a metal ion capable of planar tetracoordinate or regular octahedral coordination.
11. The water purification apparatus provided with the filtration part containing the capture | acquisition agent containing the compound represented by the following general formula (I), and the metal ion which can be planar tetracoordinated or a regular octahedral coordination, and porous solid.
    

    

    
    
    ^Wherein, R 2, ^{R 3,} and one of ^{R 4} is in the meta or para to ^{R x R y, R x} and ^{R y} are following heterocyclic independently of one another Represents a substituent,
    

    

    
    
    Of R ¹ , R ² , R ³ , R ⁴ and R ⁵ , the remainder excluding R ^y is independently a hydrogen atom, a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms, or a sulfonic acid Represents a group, but not simultaneously a hydrogen atom,
    Among the heterocyclic substituents, R ⁶ and R ⁷ each independently represent a hydrogen atom or a methyl group, and A represents a 5-membered or 6-membered heterocyclic group containing at least one nitrogen atom. ]
12. The water purifier according to claim 11, wherein the filtration unit includes a capturing unit including the capturing agent, and an adsorption unit connected to the capturing unit and including the porous solid.
13. A water purification set comprising a scavenger comprising a compound represented by the following general formula (I) and a metal ion capable of planar tetracoordinate or regular octahedral coordination, and a porous solid.
    

    

    
    
    ^Wherein, R 2, ^{R 3,} and one of ^{R 4} is in the meta or para to ^{R x R y, R x} and ^{R y} are following heterocyclic independently of one another Represents a substituent,
    

    

    
    
    Of R ¹ , R ² , R ³ , R ⁴ and R ⁵ , the remainder excluding R ^y is independently a hydrogen atom, a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms, or a sulfonic acid Represents a group, but not simultaneously a hydrogen atom,
    Among the heterocyclic substituents, R ⁶ and R ⁷ each independently represent a hydrogen atom or a methyl group, and A represents a 5-membered or 6-membered heterocyclic group containing at least one nitrogen atom. ]

Images