KR101661073B1 - Method for selectively fixing persistent organic pollutant using cyclodextrin polymer - Google Patents

Abstract

The present invention provides a method of selectively sticking POPs contained in or attached to a liquid medium or a solid substance using a cyclodextrin polymer and efficiently removing the POPs.
The present invention relates to a method for cleaning a solid medium containing residual organic contaminants or a solid material to which a residual organic contaminant is adhered with a low polarity organic solvent and then washing the polymer with a cyclodextrin and an organic dibasic acid or an organic dibasic acid halide condensed A method in which a cyclodextrin polymer that may have an alkyl group or an aryl group at the end of the polymer is contacted with a low polarity organic solvent used for the cleaning to selectively fix the residual organic contaminant to the cyclodextrin polymer .

Description

METHOD FOR SELECTIVELY FIXING PERSISTENT ORGANIC POLLUTANT USING CYCLODEXTRIN POLYMER USING CYCLODEXTRIN POLYMER BACKGROUND OF THE INVENTION [0001]

The present invention relates to a method for selectively sticking and removing residual organic contaminants using a cyclodextrin polymer improved to be water-insoluble in water-soluble cyclodextrin. As the cyclodextrin polymer, a condensation polymer obtained by condensing an organic dibasic acid with a cyclodextrin, or a condensation polymer obtained by condensing alcohols, aryl alcohols or phenols at the end of a condensation polymer obtained by condensing an organic dibasic acid with a cyclodextrin Polymer can be used.

The present inventors have so far proposed a method for selectively removing a halogenated aromatic compound by using various cyclodextrin polymers. The term " halogenated aromatic compound " refers to all compounds in which an aromatic compound is substituted with at least one of fluorine, chlorine, bromine and iodine, but these compounds are classified as " residual organic pollution Quot; Persistent Organic Pollutants " (hereinafter referred to as " POPs "). POPs are substances that are difficult to decompose on their own and can affect the human body or ecosystem by bioconcentration. They are not easily decomposed in the environment (persistence), are easily accumulated in the body of organisms by food chain (bioaccumulation) , It is easy to accumulate in the polar region (long-distance mobility) by moving long distance, and is harmful to the health of living things including human being (toxicity). The substances listed in Table 1 as POPs-designated substances are listed.

In the table, the "World Action Plan on Environmental Issues" and the plan for environmental issues, such as aldrin, chlordane, dieldrin, endrin, heptachlor, hexachlorobenzene, mylex, toxaphene, DDT, PCDD, PCDF, In the "Washington Declaration", which represents the commitments of each country, the "12 POPs considered to be particularly urgent in response", and to reduce emissions of these substances, a regulatory international framework It is stipulated to act for establishment. At present, there are 12 kinds of target substances added, and 21 kinds have been added. Then, in 2011, one kind is added again, and the above 22 kinds are registered. It is highly expected that the target substance will be added even after the curing. Candidate materials include Dechlorane Plus, polychlorinated naphthalene (PCN), and the like.

As described above, the properties of POPs are not limited in their properties such as resistance to degradation (not well decomposed in the environment), adaptability (easy to concentrate in living organisms), long-range mobility Ease of use), toxicity (toxicity to human health or ecosystems), and therefore POPs are left untreated in various places. For example, a PCB remains in a large amount of untreated oil in a transformer or a capacitor. In addition, many soils contaminated by PCBs have been reported in various places and are being left out because effective treatment techniques have not been established at present.

As described above, the present inventors have focused on a selective fixing method of a halogenated aromatic compound using various cyclodextrin polymers and have developed various techniques (Patent Document 1, Patent Document 2, Patent Document 3, etc.).

Cyclodextrin refers to a cyclic oligosaccharide in which 6, 7, or 8 glucose are linked in a cyclic manner, and is called? -,? - or? -Cyclodextrin, respectively. Cyclodextrins have the property of encapsulating various compounds in their cyclic vacancies. With this property, a hydrophobic substance can be encapsulated in the cyclodextrin and dissolved in water, or can be used for various adsorption / separation operations. However, since cyclodextrin is highly water-soluble, its use in organic solvents is limited. Thus, attempts have been made to make the cyclodextrin water-insoluble in many ways.

As an attempt to make the cyclodextrin insoluble in water, there has been known a method of polymerizing it. It has heretofore been known that a cyclodextrin derivative is reacted with chloromethylpolystyrene and cyclodextrin is immobilized on a water-insoluble polymer compound. It is also well known that cyclodextrin is crosslinked with epichlorohydrin to give a polymer compound.

Patent Document 1 discloses that a cyclodextrin is reacted with terephthalic acid to polymerize it. Patent Document 1 discloses a method for producing a cyclodextrin polymer in which a cyclodextrin and terephthaloyl dichloride are condensed to form a cyclodextrin polymer having a terminal carboxyl group derived from terephthaloyl dichloride at the terminal thereof and a method in which cyclodextrin and dimethyl terephthalate are condensed, , And a method for producing a crosslinked cyclodextrin polymer by condensing cyclodextrin with various organic dibasic acids, respectively. In the example of Patent Document 1, the cyclodextrin polymer thus prepared is used to prepare a halogenated aromatic compound (hereinafter, referred to as " PCB type ") comprising polychlorobiphenyls such as monoclorobiphenyl and trichlorobiphenyl It is possible to selectively fix the metal plate.

Patent Document 2 discloses a process for producing a porous material which is obtained by reacting an alcohol, an allyl alcohol or a phenol with an end of a polymer obtained by condensing an organic dibasic acid or an organic dibasic acid halide with a cyclodextrin, The preparation of a cyclodextrin polymer is described. In the example of Patent Document 2, it is disclosed that halogenated aromatic compounds including PCBs can be selectively fixed by using such a polymer.

Patent Document 3 discloses a selective fixing agent containing a polymer obtained by condensing an organic dibasic acid with? -Cyclodextrin. In the embodiment of Patent Document 3, it is disclosed that halogenated aromatic compounds including PCBs can be selectively fixed by using such a polymer.

It is known that the cyclodextrin polymers described in these patent documents can effectively fix halogenated aromatic compounds, but it has been examined whether or not these cyclodextrin polymers can be applied to the selective fixation of POPs. As a result of intensive investigations, the present inventors have found that a liquid material containing POPs or a solid material having POPs attached thereto is washed or extracted with iso-octane as an organic solvent to remove POPs from a specific low-polarity organic solvent (especially hydrocarbon- Solvent, etc.), and then POPs can be very effectively removed by fixing the POPs to the cyclodextrin polymers.

Japanese Patent No. 4836087 WO2011 / 102346 Japanese Laid-Open Patent Publication No. 2010-247083

The present invention provides a method of selectively sticking POPs contained in or attached to a liquid medium or a solid substance using a cyclodextrin polymer and efficiently removing the POPs.

Aspects of the present invention are as follows:

[1] A liquid medium containing a residual organic contaminant or a solid material to which a residual organic contaminant is adhered is washed with a low polarity organic solvent,

A cyclodextrin polymer which may have an alkyl group or an aryl group at the terminal of the polymer and a low polarity organic solvent used for the washing may be used as the polymer in which the cyclodextrin and the organic dibasic acid or the organic dibasic acid halide are condensed, Wherein the residual organic contaminants are selectively fixed to the cyclodextrin polymer.

[2] The organic electroluminescent device according to any one of [1] to [4], wherein the low polarity organic solvent is a hydrocarbon solvent selected from the group consisting of n-octane, isooctane, n-decane, n-undecane, n-decane, normal tridecane, cyclohexane and methylcyclohexane, A fluorine-based solvent selected from the group consisting of ethers, and a mixed solvent of two or more thereof.

The organic dibasic acid or organic dibasic acid halide is selected from the group consisting of terephthalic acid, isophthalic acid, maleic acid, malic acid, malonic acid, succinic acid, fumaric acid, glutaric acid, adipic acid, phthalic acid or halides thereof , [1] or [2].

[4] The method according to any one of [1] to [3], wherein the alkyl group is selected from alkyl groups having 1 to 20 carbon atoms, and the aryl group is selected from a benzyl group, a substituted benzyl group, a phenyl group or a substituted phenyl group.

[5] The method according to any one of [1] to [4], wherein the liquid medium is selected from the group consisting of water, organic liquid, insulating oil, machine oil, heat medium, lubricant, plasticizer, .

The present invention will be described in detail. One aspect of the present invention is a method for cleaning a solid medium with a residual organic contaminant or a solid material to which a persistent organic contaminant is adhered is washed with a hydrocarbon solvent and then the cyclodextrin and an organic dibasic acid or an organic dibasic acid halide As the condensed polymer, a cyclodextrin polymer which may optionally have an alkyl group or an aryl group at the end of the polymer is contacted with isooctane used for washing to selectively fix the residual organic contaminant to the cyclodextrin polymer to be.

Persistent Organic Pollutants (POPs) to be selectively adhered and removed by the method of the present invention means the "Stockholm Convention on Persistent Organic Pollutants" (effective May 17, 2004, as of January 2012, 150 countries and Europe Annex B and Annex C of the Treaty, signed by the Union (EU), signed by 176 countries including Japan, and the EU. POPs includes 22 kinds of substances listed in Table 1 as of July 2012. POPs are expected to increase in the future, and substances that are likely to be newly designated in the future are included in the residual organic pollutants to be adhered and removed by the method of the present invention.

In the present invention, the term " liquid medium " includes any liquid substance that may contain POPs. Examples of the liquid medium likely to contain POPs include water, organic liquid, insulating oil, machine oil, heat medium, lubricant, plasticizer, paint and ink, and mixtures thereof.

In the present invention, the term " solid substance " includes any solid substance that may have POPs attached thereto. It is a solid material with a high possibility of POPs attached, for example, metals, paper, wood, fibers, resins and plastics, as well as soil, building timber, textile products, clothing, All solid materials, such as parts, can be mentioned.

The low-polarity organic solvent used in the method of the present invention means that the polarity of the organic solvent is relatively low. Examples of the low-polarity organic solvent include hydrocarbon-based solvents selected from the group consisting of n-octane, isooctane, n-decane, n-decane, n-dodecane, n-tridecane, cyclohexane, and methylcyclohexane, Fluorine-based solvents selected from the group consisting of fluorine-based solvents, and mixed solvents of two or more thereof. In particular, in the method of the present invention, it is preferable to use a hydrocarbon-based solvent which is a liquid at room temperature and at normal pressure as a low-polarity organic solvent. Here, the fluorine-based solvent includes linear, branched or cyclic alkanes or ethers generally substituted by one or more fluorine, known as fluoroalkane or fluoroether, and examples thereof include 1, 1,1,3,3-pentafluorobutane (HFC-365mfc), 1,1,2,2,3,3,4-heptafluorocyclopentane (HFC-c-447ef), 1,1,1 , 2,2,3,4,5,5,5-decafluoropentane (HFC-43-10mee), 1,1,1,2,2,3,3,4,4,5,5,6 , 6-tridecafluorohexane (HFC-52-13p), 1,1,1,2,2,3,3,4,4,5,5,6,6,8,8,8,8-hexadecane Fluoro-octane (HFC-76-13sf), 1,1,1,2,2,3,3,4,4-nonafluoro-4-methoxybutane (including isomers) (HFE-449s-c) , 1,1,1,2,2,3,3,4,4-nonafluoro-4-ethoxybutane (including isomers) (HFE-569sf-c), 1,1,1,2,2 , 3,4,5,5,5-decafluoro-3-methoxy-4- (trifluoromethyl) pentane (HFE-64-13), 1,1,1,2,3,3- Fluoro-4- (1,1,2,3,3,3-hexafluoropropoxy) pentane (HFE-77-12), 1,1,2,2-tetrafluoro- 1- (2,2,2-trifluoroethoxy) ethane (HFE-347pc-f).

In the method of the present invention, first, a liquid medium containing POPs or a solid material to which POPs are attached is washed with a low-polarity organic solvent. The term "clean" means that a liquid medium containing POPs or a solid substance with POPs attached thereto is contacted with a low-polarity organic solvent to remove POPs contained in the liquid medium or POPs attached to the solid substance from a liquid medium or a solid substance The transition to a low-polarity organic solvent. As a method for converting POPs into a low-polarity organic solvent, there are a method of extracting and separating using a liquid medium containing POPs and a low-polarity organic solvent, a method of mixing and stirring a solid substance having POPs attached thereto and a low-polarity organic solvent, Or a method in which a low-polarity organic solvent is put on a solid material to which POPs are attached, that is, POPs are contacted with a low-polarity organic solvent to remove a liquid medium or a solid substance, Any means may be taken as a method.

Next, the cyclodextrin polymer used in the method of the present invention will be described.

Cyclodextrin is a kind of cyclic oligosaccharide in which several molecules of D-glucose are linked by α (1 → 4) glucosidic bonds and has a cyclic structure. Depending on the number of bound D-glucose, α- (6 ),? - (7), and? -Cyclodextrin (8). Cyclodextrin has high water solubility because it has a hydroxy group outside the cyclic structure, but hydrophobic molecules can be encapsulated in the inside of the pore structure.

The organic dibasic acid is, for example, an aliphatic dicarboxylic acid, an aromatic dicarboxylic acid, an alicyclic dicarboxylic acid, a fatty acid and the like, and the organic dibasic acid halide is a halide of these acids . These compounds react with the hydroxyl groups in the above-mentioned cyclodextrin molecules and can undergo a sequential condensation to form a condensation polymer. Examples of the organic dibasic acid and organic dibasic acid halide include terephthalic acid, isophthalic acid, glutaric acid, adipic acid, maleic acid, fumaric acid, phthalic acid and their chlorides, bromides and iodides In the present invention, it is particularly preferable to use terephthalic acid or terephthalic acid dichloride (terephthaloyl dichloride).

Polymers condensed with cyclodextrins and organic dibasic acids or organic dibasic acid halides can selectively bind POPs per se. The cyclodextrin polymer in which an alkyl group or an aryl group is introduced at the terminal by reacting an alcohol, an allyl alcohol or a phenol at the end of the reaction for condensing a cyclodextrin with an organic dibasic acid or an organic dibasic acid halide to obtain a condensation polymer, POPs can be fixed. Representative examples of cyclodextrin polymers for use in the method of the present invention include, for example,

[Chemical Formula 1]

or

(2)

Of the polymer. Formula 1 is a polymer in which cyclodextrin and terephthalic acid are condensed. In this formula, the cyclodextrin moiety is represented by a cone configuration, and terephthalic acid (terephthaloyl dichloride) is used as an organic dibasic acid. The hydroxyl group in the cyclodextrin and the organic dibasic acid are alternately bonded by the ester bond to form a network structure. And the terminal of the polymer is a carboxyl group derived from terephthalic acid. Formula 2 is a polymer in which a methyl group is introduced at the end of a polymer in which cyclodextrin and terephthalic acid are condensed. In this formula, the cyclodextrin moiety is represented by a cone configuration, and terephthalic acid (terephthaloyl dichloride) is used as an organic dibasic acid. The hydroxyl group in the cyclodextrin and the organic dibasic acid are alternately bonded by the ester bond to form a network structure. The end of the polymer is capped with a methyl group as a result of reaction with methanol. When the methanol is reacted at the end of the condensation reaction, the terminal group is -COOCH _3. By reacting other alcohols, aryl alcohols or the like, an alkyl group having 1 to 10 carbon atoms, a benzyl group, a substituted benzyl group, a phenyl group, And an aryl group selected from substituted phenyl groups.

There are many hydroxyl groups in the cyclodextrin, but the substituents involved in the condensation are the moieties of -CH ₂ OH, which are 6 in the case of? -Cyclodextrin, 7 in the case of? -Cyclodextrin and 7 in the case of? -Cyclodextrin If present in 8 molecules. The condensation polymer to be obtained may be a crosslinked structure or a three-dimensional network structure in addition to cyclic condensation of linear cyclodextrin and organic dibasic acid in an alternating manner.

As described above, when the low-polarity organic solvent used for cleaning the POPs is brought into contact with the above-mentioned cyclodextrin polymer, the POPs dissolved in the low-polarity organic solvent are fixed to the predominantly annular portion in the cyclodextrin polymer, A low-polarity organic solvent can be obtained.

The method of the present invention is characterized in that POPs contained in a liquid medium or POPs attached to a solid substance are cleaned using a low polarity organic solvent. Since POPs are very soluble in low polarity organic solvents, POPs contained in liquid media or POPs attached to solid substances can be almost completely converted to low polarity organic solvents. When the low-polarity organic solvent containing POPs used in the cleaning is contacted with the cyclodextrin polymer, the POPs dissolved in the low-polarity organic solvent are fixed to the cyclodextrin polymer to obtain a low-polarity organic solvent not containing POPs . The reason why it is very effective to use a low-polarity organic solvent to transfer the POPs contained in the liquid medium or the POPs attached to the solid substance to the cyclodextrin polymer finally can not be precisely known at present. It is known that POPs can be removed very efficiently by using a hydrocarbon-based solvent as a low-polarity organic solvent. However, the present inventors have found that a hydrocarbon-based solvent is a two-component solvent for POPs, and further, a hydrocarbon-based solvent is a cyclodextrin in a cyclodextrin polymer It is presumed that this is because it is a solvent having any property that enables the ring-shaped portion and the POPs to have an effective contact structure. According to the method of the present invention, POPs can be removed from a liquid medium in which movement is limited due to the presence of trace amounts of POPs, or solid substances that can not be incinerated because a small amount of POPs are attached, The removed liquid medium or the solid material can be incinerated and discarded by a conventional method. Also, when POPs transferred from a liquid medium or a solid material to a low-polarity organic solvent are fixed to the cyclodextrin polymer, the volume is reduced to a greater extent than that contained or adhered to the liquid medium or solid material, It becomes possible to reduce it.

The cyclodextrin polymer used in the method of the present invention can be obtained, for example, by the methods described in Patent Documents 1 to 3. For example, a polymer obtained by treating a terminal of a polymer obtained by condensing a commercially available? -Cyclodextrin (hereinafter referred to as? -CD) and a terephthaloyl dichloride with a methyl group (hereinafter referred to as "terephthalic acid? -CD-methyl polymer" Or " TPGCDM polymer "):

First, γ-CD is dissolved in an organic solvent (eg, pyridine, dimethylsulfoxide, dimethylformamide, 1-methylimidazole, etc.). The concentration of? -CD in the organic solvent is preferably 5 to 20% by weight. On the other hand, 4 to 12 times (mol) of terephthaloyl dichloride of the prepared? -CD is dissolved in an organic solvent (for example, tetrahydrofuran, dichloromethane, 1,4-dioxane, xylene, dimethylformamide, ) At a concentration of 10 to 40% by weight, and this was added dropwise to the? -CD solution prepared above and vigorously stirred. Since heat is generated as the condensation reaction between γ-CD and terephthaloyl dichloride progresses, it is preferable to carry out the dropwise addition while cooling the γ-CD solution in an ice bath or the like. Preferably, the temperature in the reaction vessel is maintained in the range of about 0 to 20 占 폚. After the dropwise addition, the temperature in the reaction vessel is raised to a range of about 60 to 70 캜 and stirred. Next, the temperature in the reaction vessel is slightly lowered to about 55 to 65 DEG C, and then an alcohol (preferably an aliphatic alcohol having 1 to 10 carbon atoms, preferably 30 to 80 wt% ), Aryl alcohols (preferably benzyl alcohol or substituted benzyl alcohol), or phenols (preferably phenol or substituted phenols) are added. For example, when methanol is added as the alcohol, the stirring can be continued for about 1 to 24 hours. Since the crystals of the cyclodextrin polymer end-capped with methyl groups are thus precipitated, the precipitated crystals are collected by filtration and washed with water and acetone to obtain a cyclodextrin polymer (terephthalic acid? -CD-methyl polymer ) Can be obtained. Identification of the polymer to be obtained can be carried out by infrared absorption, and observation of the shape and the like can be carried out by an electron microscope.

Next, an example of a method of removing POPs from a solid substance to which POPs are attached will be described in detail. First, solid substances (for example, glass beads) contaminated with polychlorobiphenyls (PCBs), which are POPs, are put into iso-octane which is a low-polarity organic solvent and stirred well. The mixture is allowed to stand for a while and then decanted to obtain isooctane in which POPs are dissolved. By this operation, glass beads from which POPs have been removed can be obtained. Subsequently, iso-octane in which POPs are dissolved and cyclodextrin polymer in which POPs are dissolved is added to iso-octane in which POPs are dissolved by adding a cyclodextrin polymer and stirring or by passing iso-octane through which POPs are dissolved in a column packed with a cyclodextrin polymer. . During this contact, the POPs dissolved in isooctane interact with the cyclodextrin cyclic moiety in the cyclodextrin polymer and are encapsulated therein, so that the POPs migrate from isooctane to the cyclodextrin polymer. In this way, isooctane containing no POPs can be obtained.

By carrying out the method of the present invention, it is possible to transfer POPs from the bulk liquid medium which has been limited or left in motion to the cyclodextrin polymer because the POPs are dissolved in a trace amount, can do. Since POPs can be transferred from a fiber product or the like that has a small amount of POPs attached thereto and can not be stored, the POPs can be transferred to the cyclodextrin polymer. Therefore, this can be incinerated by a conventional method.

Example

[Synthesis Example 1]

(hereinafter referred to as " terephthalic acid? -CD-methyl polymer " or " TPGCDM polymer ") treated with a methyl group at the terminal of the polymer condensed with? -cyclodextrin and terephthaloyl dichloride

(50 g, 0.039 mol, content of water of 1% or less, manufactured by Junsei Chemical Co., Ltd.) was added to a 1-liter four-necked separable flask equipped with a dropping funnel, a three-way cock equipped with a balloon, and a stirrer (660 ml, manufactured by Wako Pure Chemical Industries, Ltd.) and the mixture was stirred at room temperature for 1 hour. After the flask was immersed in an ice bath, dicarboxylic terephthaloyl (78.3 g, 0.39 mol, Tokyo Chemical Industry Co., Ltd.) dissolved in special grade tetrahydrofuran (220 ml, Wako Pure Chemical Industries) was added dropwise over 1 hour. After the dropwise addition, the ice bath was removed, and the mixture was stirred at 70 캜 for 3 hours with an internal bath (70 캜). After completion of the reaction, the internal temperature was lowered to 65 占 폚, and primary methanol (100 ml, manufactured by Junsei Kagaku Kogyo) was added and stirred for 2 hours. The crystals were suction filtered and the obtained crystals were washed with water (400 ml x 3) and primary acetone (400 ml x 1, Junsei Kagaku Kogyo) in this order, and the obtained solid was vacuum-dried overnight at 120 ° C. 105 g of terephthalic acid-γ-CD-methyl polymer (hereinafter abbreviated as TPGCDM) was obtained. IR (KBr) 3448, 1719, 1277, 1105, 1018, 732 cm < ^{-1 &}

[Example 1]

Verification of selection stability of POPs by TPGCDM polymer

It was verified whether or not the POPs PCB could be fixed by the cyclodextrin polymer.

(Polyethylene filter, diameter 5.7 mm 占 thickness 1 mm, pore diameter 20 占 퐉, JEI Science) was provided in an emptied reservoir (capacity 1 ml, inner diameter 5.7 mm 占 length 57 m, On this filter, 100 mg of the TPGCDM polymer synthesized in Synthesis Example 1 was charged, and another filter was installed on the upper portion to sandwich the TPGCDM polymer. 20 μl of isooctane (Kanto Chemical, 2,2,4-trimethylpentane, concentration 7.5 ppm) in which a PCB mixture (a mixture of 66 kinds of PCB compounds described in Table 2 and Table 3) was dissolved was added to the TPGCDM polymer Impregnated. Subsequently, pure isooctane was added thereto, and the syringe was pressed to obtain 4 ml of isooctane from the bottom of the TPGCDM polymer. PCBs in recovered isooctane were measured by gas chromatography, and no PCBs were detected.

[Examples 2 to 11]

Verification of selection stability of POPs by TPGCDM polymer

According to the method of Example 1, it was verified whether or not it is possible to fix various POPs by a cyclodextrin polymer. The concentrations in POPs and isooctane used in Examples 2 to 11 are shown in Table 4. The polychlorinated naphthalene (hereinafter referred to as "PCN") used in Examples 10 and 11 is a compound in which a large number of structural isomers (75 kinds) similar to those of PCB are present. Since the compound has the same persistence and toxicity, it has been verified whether it can be fixed by the method of the present invention.

In the table, KC-500 is polychlorobiphenyl manufactured by Wako Pure Chemical Industries, Ltd. PCBs in iso-octane recovered from Examples 2 to 11 were measured by gas chromatography, and no PCBs were detected.

[Examples 12 to 24]

Verification in the case of using an organic solvent other than isooctane

The same experiment as in Example 1 was conducted except that pure iso-octane was used in Example 1, and the organic solvent was recovered using the low-polarity organic solvent shown in Table 5. [

The organic solvents in the table are as follows:

 NS clean: NS Clean 200P manufactured by JX Nikkoshi Electric Energy Co.

Novec 7300: Fluorine ether type solvent (C ₂ F ₅ CF (OCH ₃ ) C ₃ F ₇ , manufactured by 3M Company, boiling point: 98 ° C, no flash point)

Novec 7600: Fluorine ether solvent (C ₃ HF ₆ CH (CH ₃ ) OC ₃ HF ₆ , manufactured by 3M Company, boiling point: 131 캜, no flash point)

PCBs in the respective organic solvents recovered from Examples 12 to 24 were measured by gas chromatography, and no PCBs were detected.

[Comparative Examples 1 to 16]

The same experiment as in Example 1 was conducted except that pure isooctane was used in Example 1, and the organic solvent described in Table 6 was used to recover the organic solvent.

The TPBCDM polymer used in Comparative Example 16 (polymer obtained by treating the terminal of a polymer obtained by condensing? -Cyclodextrin and terephthaloyl dichloride with a methyl group ("terephthalic acid? -CD-methyl polymer") was synthesized by the following method will be :

[Synthesis Example 2]

50 g of β-cyclodextrin (hereinafter abbreviated as β-CD) was added to a 1 L four-necked separable flask equipped with a dropping funnel, a three-way cock equipped with a balloon, a valve and a stirrer 0.044 mol, a water content of 1% or less, manufactured by Junsei Chemical Co., Ltd.) and a special grade pyridine (660 ml, manufactured by Wako Pure Chemical Industries) were added and stirred at room temperature for 1 hour. The flask was immersed in an ice bath and dicyclohexylterephthaloyl (89.4 g, 0.44 mol, Tokyo Chemical Industry Co., Ltd.) dissolved in a special grade tetrahydrofuran (230 ml, Wako Pure Chemical Industries) was added dropwise over 1 hour. After the dropwise addition, the ice bath was removed, and the mixture was stirred for 4 hours at 70 deg. C by internal warming (70 deg. C). After completion of the reaction, the internal temperature was lowered to 65 占 폚, and primary methanol (35.6 ml, 0.88 mmol, Junsei Chemical) was added and the mixture was stirred for 4 hours. The crystals were collected by suction filtration and washed with primary methanol (400 ml × 2, manufactured by Junsei Chemical), water (400 ml × 3) and primary acetone (400 ml × 2, The solids were vacuum dried overnight at 120 < 0 > C. 98.7 g of TPBCDM polymer was obtained. IR (KBr): 3448, 1718, 1277, 1105, 1018, 731 cm < ^{-1 &}

[Example 25]

PCB removal from PCB contaminated gravel

5 g of isooctane (PCB was used as the PCB mixture used in Example 1) in which PCB was dissolved at a concentration of 7.5 ppm was added to gravel (sodosa, sand of tropical fish and goldfish, 10 g) . Pure isooctane (10 ml) was added to the gravel of the model, stirred well and stopped. After filtration, model gravel and PCB contaminated isooctane were separated. This PCB contamination was measured by mass spectrometry of PCB concentration in iso-octane. As a result of estimating the amount of PCB contained in PCB contaminated isooctane, it was confirmed that the amount of PCB existing in 5 g of isooctane I could. That is, it was found that the PCB in the gravel was almost completely removed in the cleaning process by pure isooctane. On the other hand, a filter (polyethylene filter, diameter 5.7 mm 占 thickness 1 mm, pore size 20 占 퐉, JEI Science Co., Ltd.) was provided in an emptied reservoir (capacity 1 ml, inner diameter 5.7 mm 占 57 m, On this filter, 100 mg of the TPGCDM polymer synthesized in Synthesis Example 1 was charged, and another filter was installed on the upper portion to sandwich the TPGCDM polymer. On top of this, 4.5 ml of PCB contaminated isooctane was injected into the TPGCDM polymer. Subsequently, pure isooctane was added thereto to recover 4 ml of isooctane from the bottom of the TPGCDM polymer. PCBs in recovered isooctane were measured by gas chromatography, and no PCBs were detected.

[Example 26]

PCB removal from glass beads contaminated with PCB

A model of glass beads contaminated with PCB was prepared by adding 5 g of isooctane (PCB was used in the PCB mixture used in Example 1) in which PCB was dissolved at a concentration of 7.5 ppm in glass beads (Daiso, 10 g) . Using this model glass beads, the treatment was carried out in the same manner as in Example 25 to contact with the TPGCDM polymer. PCBs in iso-octane recovered finally were analyzed by gas chromatography and no PCBs were detected.

[Example 27]

Removal of PCB from PCB contaminated stainless steel piece

5 g of isooctane (PCB was used as the PCB mixture used in Example 1) in which PCB was dissolved in a concentration of 7.5 ppm was applied to a stainless steel piece (SUS304, 10 mm x 20 mm), and a model of the stainless steel piece contaminated with PCB . The model stainless steel piece was immersed in isooctane (10 ml). Thereafter, treatment was carried out in the same manner as in Example 25 to contact with the TPGCDM polymer. PCBs in iso-octane recovered finally were analyzed by gas chromatography and no PCBs were detected.

Claims (6)

A liquid medium containing a persistent organic contaminant or a solid material having a persistent organic contaminant attached thereto is selected from the group consisting of normal hexane, n-octane, isooctane, n-decane, n-undecane, nordododecane, nordestradecane, nordatetradecane, Methylcyclohexane, and a solvent selected from the group consisting of two or more mixed solvents thereof. Subsequently,
As a polymer in which an organic dibasic acid or an organic dibasic acid halide is condensed with a cyclodextrin, a cyclodextrin polymer, which may optionally have an alkyl group or an aryl group at the end of the polymer, is brought into contact with the solvent after the washing, Wherein the organic contaminants are selectively fixed to the cyclodextrin polymer. delete The method according to claim 1,
Wherein the organic dibasic acid or organic dibasic acid halide is selected from terephthalic acid, isophthalic acid, maleic acid, malic acid, malonic acid, succinic acid, fumaric acid, glutaric acid, adipic acid, phthalic acid or halides thereof. The method according to claim 1 or 3,
Wherein the alkyl group is selected from alkyl groups having 1 to 10 carbon atoms and the aryl group is selected from a benzyl group, a substituted benzyl group, a phenyl group or a substituted phenyl group. The method according to claim 1 or 3,
Wherein the liquid medium is selected from the group consisting of water, organic liquids, insulating oils, machine oils, thermal media, lubricants, plasticizers, paints and inks, and mixtures thereof. 5. The method of claim 4,
Wherein the liquid medium is selected from the group consisting of water, organic liquids, insulating oils, machine oils, thermal media, lubricants, plasticizers, paints and inks, and mixtures thereof.