JP2005172758A - Method and apparatus for preparing sample for analyzing dioxins - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To simply and efficiently prepare two kinds of samples containing different dioxins from a material polluted with dioxins in a short time. <P>SOLUTION: This preparation apparatus of two kinds of the samples for analyzing dioxins is composed of: an extraction part 2 for obtaining an extraction fluid of dioxins from the polluted material housed in a cell 20 by a supercritical fluid; an adsorbing column 3 having a first adsorbent material 31 adsorbing dioxins in the extraction fluid; a first solvent supply part 5 for supplying a first aliphatic hydrocarbon solvent to the adsorbing column 3; a fractionation column 8 receiving the first aliphatic hydrocarbon solvent from the adsorbing column 3 refined in a refining column 6, wherein second and third adsorbent materials 83 and 84 having different specific surface areas are arranged in a two-layered state, from the side of the second adsorbent material 83; a second solvent supply part 10 capable of supplying a second aliphatic hydrocarbon solvent to the fractionation column 8 from the side of the second adsorbent material 83; and a third solvent supply part 12 supplying an aromatic hydrocarbon solvent to the fractionation column 8 form the side of the third adsorbent material 84. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a sample preparation method and preparation apparatus for analysis of dioxins, and more particularly to a method and apparatus for preparing a sample for analysis of dioxins from a contaminated material contaminated by dioxins.

  Exhaust gas generated from incineration facilities for incineration of industrial waste and general household waste, incineration ash such as fly ash and furnace bottom ash generated at the facility, and wastewater from various factories such as paper mills Soil, sludge, etc. may contain dioxins. Since dioxins are extremely toxic environmental pollutants as is well known, they are subject to elimination and reduction in the Special Measures Act against Dioxins (Act No. 105 of 1999). For this reason, it is necessary to periodically analyze the contents of dioxins in exhaust gas from the incineration facility, air, factory waste water, incineration ash, soil, and the like.

  In the present application, the term dioxins follows the provisions of Article 2 of the Special Measures Law for Countermeasures against Dioxins. In addition to polychlorinated dibenzo-para-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), coplanar polychlorinated biphenyls (Co— PCBs).

  In the case of analyzing dioxins contained in a fluid such as exhaust gas or waste water or in soil, it is first necessary to extract dioxins from a sample such as exhaust gas or soil to prepare a sample for analysis. Here, when the sample is a solid such as soil or incinerated ash, dioxins are extracted from the solid by an extraction method using a hydrophobic solvent such as n-hexane (eg, Soxhlet extraction method), The extract is used as an analysis sample (see, for example, Non-Patent Documents 1, 2, and 3).

  On the other hand, when the specimen is a fluid such as exhaust gas or waste water, first, for example, the glass impinger described in Non-Patent Document 4 or the filters described in Patent Documents 1 and 2 are used to dioxins in the fluid. Is captured and collected. Then, the dioxins collected by a glass impinger or filter are extracted by an extraction method using a hydrophobic solvent such as n-hexane (for example, a soxhlet extraction method or a cleaning method such as a glass impinger), and the extraction is performed. The liquid is used as a sample for analysis (see Non-Patent Document 4, Patent Documents 1 and 2).

  However, these methods require a large amount of a hydrophobic solvent to extract dioxins from contaminated substances, and thus are inefficient and uneconomical. Moreover, the extraction requires a long time of at least several days. Cost.

  In addition, the extract obtained through the above-described steps, that is, the hydrophobic solvent solution of dioxins is usually purified and concentrated, and then qualitatively used using a gas chromatograph mass spectrometer (GC / MS). And analyzed quantitatively. However, since dioxins are a mixture of many kinds of compounds, a highly reliable analysis result may not be obtained if they are analyzed simultaneously. Specifically, when an extract containing monoortho-Co-PCBs, non-ortho-Co-PCBs, PCDDs, and PCDFs is analyzed by GC / MS, monoortho-Co-PCBs affects the quantitative analysis results of PCDDs and PCDFs. , PCDDs and PCDFs affect the results of quantitative analysis of monoortho-Co-PCBs. Therefore, Non-Patent Document 4 discloses that a hydrophobic solvent solution of dioxins is composed of a solution of monoortho-Co-PCBs and non-ortho-Co-PCBs and a solution of PCDDs and PCDFs in order to increase the reliability of the analysis result by GC / MS. It is recommended to separate into two types and analyze each solution separately by GC / MS.

  However, the fractionation method described in Non-Patent Document 4 is a combination of several types of column chromatography and is complicated in operation, and it takes a long time of several days to complete the fractionation.

  On the other hand, a hydrophobic solvent solution of dioxins can be used as long as monoortho-Co-PCBs, PCDDs, and PCDFs interact with each other to impair the quantitative analysis results, and monoortho-Co-PCBs, non-ortho-Co-PCBs, PCDDs. However, it is only necessary to prepare two types of analytical samples by separating them into PCDFs solutions. However, a method that can easily prepare such two types of analytical samples in a short time has not yet been realized.

  The object of the present invention is to easily and efficiently provide two types of samples, namely, a sample for analysis of monoortho-Co-PCBs and a sample for analysis of non-ortho-Co-PCBs, PCDDs and PCDFs, from contaminated substances by dioxins. It is to prepare in a short time.

“Soil Survey and Measurement Manual for Dioxins (2000)” edited by Soil Agricultural Chemicals Section, Water Quality Conservation Bureau, Environment Agency "Environmental Agency Water Quality Preservation Bureau Water Quality Management Division" Bottom Quality Survey Manual for Dioxins (2000) " “Environmental Endocrine Disrupting Chemical Substances Interim Manual (1998)” Japanese Industrial Standard JIS K 0311: 1999 established on September 20, 1999

Japanese Patent No. 327396 WO01 / 91883

The method for preparing a sample for analysis of dioxins according to the present invention is for preparing a sample for analysis of dioxins from a contaminated material contaminated with dioxins, and a supercritical fluid is brought into contact with the contaminated material. A step of obtaining an extraction fluid containing dioxins, a step of bringing the extraction fluid into contact with a first adsorbent capable of adsorbing dioxins and separating the dioxins from the extraction fluid, a first using a first aliphatic hydrocarbon solvent extracting dioxins from the adsorbent, to obtain an extract, and a second adsorbent having a specific surface area of 50~180m ² / g, a specific surface area of the third adsorbent and the two layers of 200 to 500 m ² / g Supplying the extract from the second adsorbent side to the arranged separation column, supplying the second aliphatic hydrocarbon solvent from the second adsorbent side to the separation column after the extract has passed And sorting A first securing step for securing the second aliphatic hydrocarbon solvent that has passed through the column for supply, and supplying the aromatic hydrocarbon solvent from the third adsorbent side to the separation column after the extract has passed through, A second securing step of securing the aromatic hydrocarbon solvent that has passed through the fractionation column.

  In this analytical sample preparation method, when a supercritical fluid is brought into contact with the contaminated material, the dioxins contained in the contaminated material are efficiently extracted in a short time by the supercritical fluid, and the extraction fluid containing the dioxins is obtained. can get. When the extraction fluid is brought into contact with a first adsorbent capable of adsorbing dioxins, the dioxins are adsorbed on the first adsorbent and separated from the extraction fluid. Dioxins separated from the extraction fluid, that is, dioxins adsorbed on the first adsorbent are extracted with the first aliphatic hydrocarbon solvent and obtained as an extract.

  When the extract is supplied to the separation column, among dioxins, non-ortho Co-PCBs, PCDDs, and PCDFs are mainly adsorbed on the second adsorbent, and monoortho-Co-PCBs are mainly adsorbed on the third adsorbent. To do. Since mono-ortho-Co-PCBs adsorbed on the third adsorbent is dissolved and extracted in the second aliphatic hydrocarbon solvent supplied from the second adsorbent side to the fractionation column in the first securing step, When the second aliphatic hydrocarbon solvent that has passed through the fractionation column is secured, an aliphatic hydrocarbon solvent solution of mono-ortho-Co-PCBs is obtained. On the other hand, non-ortho Co-PCBs, PCDDs, and PCDFs adsorbed on the second adsorbent are dissolved and extracted in the aromatic hydrocarbon solvent supplied from the third adsorbent side to the separation column in the second securing step. Therefore, when the aromatic hydrocarbon solvent that has passed through the separation column is secured, an aromatic hydrocarbon solvent solution of non-ortho Co-PCBs, PCDDs, and PCDFs can be obtained.

  Therefore, according to the analytical sample preparation method of the present invention, a sample for analysis of mono-ortho-Co-PCBs, i.e., an aliphatic hydrocarbon solvent solution of mono-ortho-Co-PCBs, and a non-ortho from a contaminated material contaminated with dioxins. Two types of samples for analysis of Co-PCBs, PCDDs and PCDFs, that is, aromatic hydrocarbon solvent solutions of non-ortho Co-PCBs, PCDDs and PCDFs can be prepared.

  In the analytical sample preparation method of the present invention, extraction is usually performed on a purification column packed with a stationary phase capable of capturing polar substances and not capturing dioxins before supplying the extract to the separation column. It is preferable to further include a step of passing the liquid. In this case, when the extract passes through the purification column, polar substances, that is, impurities are trapped in the stationary phase, so that the polar substances are removed and supplied to the separation column in a purified state. The

The sample preparation device for analysis of dioxins according to the present invention is for preparing a sample for analysis of dioxins from a contaminated material contaminated with dioxins, contacting the contaminated material with a supercritical fluid, Extraction unit for obtaining extraction fluid containing dioxins, adsorption column packed with first adsorbent capable of adsorbing dioxins contained in extraction fluid, and supply of first aliphatic hydrocarbon solvent to adsorption column the first solvent supply unit for the specific surface area and a second adsorbent 50~180m ² / g, specific surface area and a third adsorbent 200 to 500 m ² / g was arranged in two layers, for adsorption The first aliphatic hydrocarbon solvent supplied to the column can be received from the second adsorbent side, and the second aliphatic hydrocarbon solvent can be supplied from the second adsorbent side to the separation column. Second solvent supply And a third solvent supply unit capable of supplying an aromatic hydrocarbon solvent from the third adsorbent side to the separation column.

  In this device, when the supercritical fluid is brought into contact with the contaminated material in the extraction section, dioxins contained in the contaminated material are efficiently extracted in a short time by the supercritical fluid, and an extraction fluid containing dioxins is obtained. Can do. In this extraction fluid, dioxins are adsorbed by the first adsorbent in the adsorbent column and separated from the extraction fluid. The dioxins separated from the extraction fluid, that is, the dioxins adsorbed on the first adsorbent are extracted by the first aliphatic hydrocarbon solvent supplied from the first solvent supply unit, and the first fat is extracted. Is obtained as a group hydrocarbon solvent solution.

  When this aliphatic hydrocarbon solvent solution is received in the separation column from the second adsorbent side, among the dioxins contained therein, non-ortho Co-PCBs, PCDDs and PCDFs are mainly adsorbed on the second adsorbent, Monoortho-Co-PCBs are mainly adsorbed on the third adsorbent. Monoortho-Co-PCBs adsorbed on the third adsorbent are dissolved and extracted in the second aliphatic hydrocarbon solvent supplied from the second solvent supply unit to the second adsorbent side of the fractionation column, and are analyzed. That is, it becomes a second aliphatic hydrocarbon solvent solution of mono-ortho Co-PCBs. On the other hand, non-ortho Co-PCBs, PCDDs and PCDFs adsorbed on the second adsorbent are dissolved and extracted in an aromatic hydrocarbon solvent supplied from the third solvent supply unit to the third adsorbent side of the separation column, The sample for analysis, that is, an aromatic hydrocarbon solvent solution of non-ortho Co-PCBs, PCDDs, and PCDFs.

  Therefore, the analytical sample preparation apparatus of the present invention is a sample for analysis of mono-ortho-Co-PCBs, that is, an aliphatic hydrocarbon solvent solution of mono-ortho-Co-PCBs, and non-ortho-Co— Two types of samples for analysis of PCBs, PCDDs and PCDFs, that is, aromatic hydrocarbon solvent solutions of non-ortho Co-PCBs, PCDDs and PCDFs can be prepared.

  The analytical sample preparation apparatus of the present invention is generally a purification column for purifying the first aliphatic hydrocarbon solvent supplied to the adsorption column, which is disposed between the adsorption column and the fractionation column. Is preferably further provided. In this case, the first aliphatic hydrocarbon solvent supplied to the adsorption column is supplied to the fractionation column in a purified state.

  Since the sample preparation method for analysis of dioxins according to the present invention includes the above-described steps, the sample for analysis of mono-ortho-Co-PCBs, non-ortho-Co-PCBs, PCDDs, and PCDFs can be obtained from the contaminated material by dioxins. Two types of samples for analysis can be easily and efficiently prepared in a short time.

  In addition, since the sample preparation apparatus for analysis of dioxins according to the present invention includes the above-described elements, a sample for analysis of monoortho-Co-PCBs, non-ortho-Co-PCBs, PCDDs and Two types of PCDFs and analysis samples can be prepared easily and efficiently in a short time.

  With reference to FIG. 1, one form of the sample preparation device for analysis of dioxins according to the present invention will be described. In the figure, an analytical sample preparation apparatus 1 includes an extraction unit 2, an adsorption column 3, a first path 4, a first solvent supply unit 5, a purification column 6, a second path 7, a fractionation column 8, and a third path. 9, the second solvent supply unit 10, the fourth path 11 and the third solvent supply unit 12 are mainly provided.

  The extraction unit 2 is for extracting dioxins from contaminated materials contaminated by dioxins, and includes a cell 20 for storing the contaminated materials, an oven 21, a carbon dioxide supply device 22, and back pressure adjustment. The container 23 is mainly provided. The oven 21 is for heating the cell 20 and a part of a gas supply path 25 to be described later, and the cell 20 is accommodated in the oven 21.

  The supply device 22 mainly includes a gas cylinder 24 for carbon dioxide and a gas supply path 25. The gas supply path 25 extends from the gas cylinder 24, and includes a cooler 26 for cooling the carbon dioxide gas from the gas cylinder 24 side, a pump 27 for supplying the carbon dioxide gas into the cell 20 while being pressurized, and an injector 28. Are provided in this order. The gas supply path 25 is connected to the lower part of the cell 20 housed in the oven 21. The injector 28 is for injecting an entrainer for accelerating the extraction of dioxins from the contaminated material into the carbon dioxide gas supplied into the cell 20, and includes an entrainer storage tank 28a, An injection path 28c having a pump 28b extending from the storage tank 28a and connected to the gas supply path 25. The entrainer used here is, for example, water or an organic solvent such as methanol, acetone, or toluene.

  In the supply device 22 described above, the oven 21 and the pump 27 are capable of heating and pressurizing the carbon dioxide, respectively, so that the carbon dioxide from the gas cylinder 24 is converted into supercritical carbon dioxide (an example of a supercritical fluid). have.

  The back pressure regulator 23 is connected to a communication path 29 extending from the upper part of the cell 20, and is used for depressurizing supercritical carbon dioxide from the communication path 29 and releasing the supercritical state.

  The adsorption column 3 is a column in which a first adsorbent 31 is filled in a cylindrical body that is open in the vertical direction. The first adsorbent 31 used here is not particularly limited as long as it can adsorb dioxins, and examples thereof include silica gel, alumina, diatomaceous earth, and sodium sulfate. However, the first adsorbent 31 is made of a fiber material (a group of fiber materials) and an inorganic material because it is easy to handle and the adsorbed dioxins are easily extracted by a first aliphatic hydrocarbon solvent described later. It is preferable to use a molded article including a binder, particularly a molded article having a fluid permeability and a three-dimensional network structure. The fiber material used here is one that does not substantially chemically react with dioxins, and is usually fibrous activated carbon, carbon fiber, glass fiber, alumina fiber (preferably activated alumina fiber), silica fiber, and fluororesin fiber ( For example, Teflon fiber: Teflon is a registered trademark). On the other hand, an inorganic binder is a material that binds fiber materials together to integrate a group of fiber materials, and has a property of imparting a fixed shape to the group of fiber materials, that is, a group of fiber materials. It functions as a binder that maintains a fixed molding shape.

  The inorganic binder usable here is not particularly limited as long as it has the above-described performance and does not substantially chemically react with dioxins as in the case of the fiber material. What has the adsorption | suction performance with respect to dioxins is preferable. Examples of such inorganic binders include alumina (preferably activated alumina), zeolite (preferably synthetic zeolite), silicon dioxide (silica), acid clay, apatite, and the like. The materials may be used alone or in combination of two or more. Further, the form of the inorganic binder is not particularly limited, but usually a particulate one is used.

  It is preferable that the above-mentioned molded body is usually set to a bulk density that allows an extraction fluid described later to pass smoothly.

  An example of a method for producing such a molded body is described in, for example, WO 01/91883 (the above-mentioned Patent Document 2). Incidentally, as such a molded body, for example, “Dioana” of Miura Kogyo Co., Ltd. (“Dioana” is a registered trademark of Miura Kogyo Co., Ltd.) can be used.

  The first path 4 extends from the back pressure regulator 23 and communicates with the upper opening of the adsorption column 3 and has a first switching valve 41. The first switching valve 41 switches the first path 4 so as to be set to either communication between the back pressure regulator 23 and the adsorption column 3 or communication between the adsorption column 3 and the first solvent supply unit 5. Is for.

  The first solvent supply unit 5 is for supplying the first aliphatic hydrocarbon solvent to the adsorption column 3, and a first solvent tank 51 for storing the first aliphatic hydrocarbon solvent. And a first solvent supply path 52 for supplying the first aliphatic hydrocarbon solvent from the first solvent tank 51 to the first path 4. The first solvent supply path 52 communicates with the first switching valve 41 and has a pump 53 for feeding the first aliphatic hydrocarbon solvent. The first aliphatic hydrocarbon solvent used here preferably has 5 to 10 carbon atoms. Examples of the aliphatic hydrocarbon solvent having 5 to 10 carbon atoms include n-hexane, nonane and decane.

  The purification column 6 is disposed below the adsorbent column 3, and is a column in which a cylindrical body that opens in the vertical direction is filled with a liquid holding material 61 and a purification material 62 in order from the upper side. The purification column 6 has a heater 63 for heating. The liquid holding material 61 used here is for preventing the later-described extract from the adsorption column 3 from reaching the refining material 62 immediately, and is generally difficult to adsorb dioxins and adsorbs. Dioxins that can be easily extracted with an aliphatic hydrocarbon solvent, such as low-activity silica gel, alumina, or diatomaceous earth.

  On the other hand, the refining material 62 is usually a material that can capture polar substances and does not capture dioxins. As such a material, for example, silica gel with enhanced activity can be used. In particular, it is preferable to use sulfuric acid silica gel. Further, the silica gel used as the material may be a multi-layer silica gel in which different types of silica gel are arranged in multiple layers, for example, a silver nitrate silica gel and a sulfuric acid silica gel are arranged in multiple layers. By using a silica gel or different types of silica gel arranged in multiple layers, the purification treatment described later can be carried out more effectively and quickly.

  The second path 7 is for connecting the adsorption column 3 and the purification column 6, one end is connected to the lower opening of the adsorption column 3, and the other end is the purification column. 6 is connected to the upper opening. The second path 7 has a second switching valve 71, and a discharge path 72 branches off from the second switching valve 71. The second switching valve 71 is for switching the second path 7 so as to be set to either communication between the adsorption column 3 and the purification column 6 or communication between the adsorption column 3 and the discharge path 72. is there.

  The separation column 8 is disposed below the purification column 6, and is filled with a separation adsorbent 81 for separating dioxins in a cylindrical body that opens vertically. The separation column 8 has a heater 82 for heating.

The separating adsorbent 81 is formed in two layers in the vertical direction, the upper layer is made of the second adsorbent 83, and the lower layer is made of the third adsorbent 84. The second adsorbent 83 has a specific surface area of 50 to 180 m ² / g, preferably 70 to 120 m ² / g. When the specific surface area of the second adsorbent 83 is less than 50 m ² / g, it becomes difficult to adsorb dioxins, particularly non-ortho Co-PCBs, PCDDs, and PCDFs. Conversely, when it exceeds 180 m ² / g, it becomes difficult to fractionate dioxins, and it becomes difficult to extract the adsorbed dioxins with an aromatic hydrocarbon solvent described later.

The third adsorbent 84 has a specific surface area of 200 to 500 m ² / g, preferably 220 to 400 m ² / g. When the specific surface area of the third adsorbent 84 is less than 200 m ² / g, it becomes difficult to adsorb monoortho-Co-PCBs, and it becomes difficult to separate dioxins. On the other hand, when it exceeds 500 m ² / g, it becomes difficult to extract the adsorbed dioxins with a second aliphatic hydrocarbon solvent described later.

  The above-mentioned specific surface areas for the second adsorbent 83 and the third adsorbent 84 are based on the BET method using nitrogen.

  The materials of the second adsorbent 83 and the third adsorbent 84 are not particularly limited, but usually a carbon-based material such as graphite, activated carbon, or nanocarbon is preferable. In particular, it is preferable to use graphite that does not easily elute impurities from itself when an extraction operation using various organic solvents is performed. Further, the ratio between the second adsorbent 83 and the third adsorbent 84 in the sorting column 8 is not particularly limited, but usually, the third adsorbent 84 is more in weight than the second adsorbent 83. It is preferable to set so as to increase.

  The third path 9 is for connecting the purification column 6 and the separation column 8, one end is connected to the lower opening of the purification column 6, and the other end is the separation column. 8 is connected to the upper opening. The third path 9 has a third switching valve 91, and a second sample discharge path 92 extends from the third switching valve 91 in a branched manner. Further, the second solvent supply unit 10 communicates with the third switching valve 91. The third switching valve 91 communicates between the purification column 6 and the separation column 8, communicates between the second solvent supply unit 10 and the separation column 8, or communicates between the separation column 8 and the second sample discharge passage 92. It is for switching the 3rd path | route 9 so that it may be set to either.

  The second solvent supply unit 10 is for supplying the second aliphatic hydrocarbon solvent to the separation column 8 from the second adsorbent 83 side, and stores the second aliphatic hydrocarbon solvent. And a second solvent supply path 102 for supplying the second aliphatic hydrocarbon solvent from the second solvent tank 101 to the third path 9. The second solvent supply path 102 communicates with the third switching valve 91 and has a pump 103 for feeding the second aliphatic hydrocarbon solvent.

  Although the 2nd aliphatic hydrocarbon solvent used here is not specifically limited, Usually, they are C5-C10 aliphatic hydrocarbon solvents, for example, n-hexane, nonane, decane, etc. A preferable example of the second aliphatic hydrocarbon solvent is a solution obtained by adding at least one of an aromatic hydrocarbon solvent and a halogenated aliphatic hydrocarbon solvent to such an aliphatic hydrocarbon solvent. In particular, among the aromatic hydrocarbon solvent and the halogenated aliphatic hydrocarbon solvent, the same aliphatic hydrocarbon solvent as the first aliphatic hydrocarbon solvent supplied from the first solvent supply unit 5 to the purification column 3 is used. What added at least 1 type is preferable. In addition, what is preferable as an aromatic hydrocarbon solvent added to an aliphatic hydrocarbon solvent is toluene, benzene, etc., for example. A preferable halogenated aliphatic hydrocarbon solvent added to the aliphatic hydrocarbon solvent is, for example, dichloromethane.

  The fourth path 11 extends from the lower opening of the separation column 8, and the tip is disposed in the solvent container 111. The fourth path 11 has a fourth switching valve 112, and a first sample discharge path 113 branches off from the fourth switching valve 112 and extends. Further, the third solvent supply unit 12 communicates with the fourth switching valve 112. The fourth switching valve 112 communicates between the separation column 8 and the solvent container 111, communicates between the separation column 8 and the first sample discharge passage 113, or communicates between the separation column 8 and the third solvent supply unit 12. It is for switching the 4th path | route 11 so that it may be set to either.

  The third solvent supply unit 12 is for supplying an aromatic hydrocarbon solvent to the separation column 8 from the third adsorbent 84 side, and a third solvent tank for storing the aromatic hydrocarbon solvent. 121 and a third solvent supply path 122 for supplying an aromatic hydrocarbon solvent from the third solvent tank 121 to the fourth path 11. The third solvent supply path 122 communicates with the fourth switching valve 112 and has a pump 123 for feeding the aromatic hydrocarbon solvent. The aromatic hydrocarbon solvent stored in the third solvent tank 121 is not particularly limited, but benzene, toluene and the like are usually preferable.

  Next, an analysis sample preparation method for dioxins using the above-described analysis sample preparation apparatus 1 will be described. In the sample preparation device for analysis 1, the first switching valve 41 is set in advance so that the back pressure regulator 23 and the adsorption column 3 communicate with each other, and the second switching valve 41 communicates with the adsorption column 3 and the discharge path 72. The switching valve 71 is set in advance. In addition, the third switching valve 91 is set so that the purification column 6 and the separation column 8 communicate with each other, and the fourth switching valve 112 is set so that the separation column 8 and the solvent container 111 communicate with each other. Further, the heater 63 is operated to heat the purification column 6 in advance.

  First, the contaminated material contaminated with dioxins is accommodated in the cell 20. Here, the contaminated material is not particularly limited as long as it is a solid material contaminated with dioxins. For example, soil contaminated with dioxins, fly ash generated in a waste incineration facility or a furnace Filters obtained by capturing and collecting dioxins contained in fluids such as incineration ash such as bottom ash, exhaust gas from waste incineration facilities and wastewater discharged from various factories such as paper mills (for example, Patent Document 1 and 2).

  Next, the oven 21 is heated, and carbon dioxide is supplied from the gas cylinder 24 to the gas supply path 25. The carbon dioxide supplied to the gas supply path 25 is continuously supplied into the cell 20 while being cooled in the cooler 26, further pressurized by the pump 27, and heated in the oven 21. At this time, the pump 28b is also operated, and the entrainer in the storage tank 28a is injected into the carbon dioxide being supplied to the cell 20 through the injection path 28c.

  The carbon dioxide supplied into the cell 20 becomes supercritical carbon dioxide and comes into contact with the contaminated material accommodated in the cell 20. As a result, dioxins contained in the contaminated material are efficiently extracted in a short time by supercritical carbon dioxide. At this time, since supercritical carbon dioxide includes an entrainer, dioxins are more efficiently extracted from the contaminated material. Then, the supercritical carbon dioxide from which the dioxins are extracted is supplied from the cell 20 to the back pressure regulator 23 through the communication path 29, where the pressure is reduced. As a result, the supercritical carbon dioxide from which dioxins are extracted is separated into a gas phase and a liquid phase, and an extraction fluid containing dioxins is obtained.

  The obtained extracted fluid is supplied from the back pressure regulator 23 to the adsorption column 3 through the first path 4. Here, dioxins contained in the extraction fluid are adsorbed by the first adsorbent 31 packed in the adsorption column 3. As a result, dioxins are separated from the extraction fluid and collected in the first adsorbent 31 of the adsorption column 3. On the other hand, the extracted fluid after dioxins are separated passes through the adsorption column 3 and is discharged to the outside from the discharge path 72.

  Next, the first switching valve 41 is switched so that the first solvent supply path 52 and the adsorption column 3 communicate with each other through the first path 4. In addition, the second switching valve 71 is switched so that the adsorption column 3 and the purification column 6 communicate with each other through the second path 7. Then, the pump 53 is operated to supply the first aliphatic hydrocarbon solvent in the first solvent tank 51 to the adsorption column 3 through the first solvent supply path 52. Thereby, the dioxins adsorbed on the first adsorbent 31 of the adsorption column 3 are dissolved in the first aliphatic hydrocarbon solvent from the first solvent supply path 52, and the aliphatic hydrocarbon solvent solution, that is, Obtained as an extract. This extract is supplied to the purification column 6 through the second path 7.

  The extract supplied to the purification column 6 first permeates the liquid holding material 61 and moves to the purification material 62 while being heated by the heater 63 there. The extract moved to the purification material 62 is purified by removing contaminants by the stationary phase, and subsequently purified by the first aliphatic hydrocarbon solvent supplied from the first solvent tank 51 to the purification column 6. 6 is pushed out. Here, since the refining material 62 is heated by the heater 63 and the extract is preheated in the liquid holding material 61, impurities contained in the extract are easily adsorbed, and the refining efficiency of the extract is improved. Can be increased.

  Subsequently, the extract liquid pushed out from the purification column 6 is supplied to the second adsorbent 83 side of the separation column 8 through the third path 9. As the extract supplied to the separation column 8 passes through the separation column 8, non-ortho Co-PCBs, PCDDs, and PCDFs among dioxins contained therein are mainly adsorbed to the second adsorbent 83, and Monoortho Co-PCBs is mainly adsorbed on the third adsorbent 84. Then, the first aliphatic hydrocarbon solvent of the extract passes through the separation column 8 and is discharged to the solvent container 111 through the fourth path 11.

  After the first aliphatic hydrocarbon solvent of the extract is discharged from the separation column 8 to the solvent solution 111, the third switching valve 91 is switched so that the second solvent supply path 102 and the separation column 8 communicate with each other. In addition, the fourth switching valve 112 is switched so that the separation column 8 and the first sample discharge passage 113 communicate with each other. In this state, the pump 103 is operated, and the second aliphatic hydrocarbon solvent stored in the second solvent tank 101 is passed through the second solvent supply path 102 and the third path 9 in the second column 8 for separation. Supply to the adsorbent 83 side.

  The second aliphatic hydrocarbon solvent supplied to the fractionation column 8 flows down the fractionation column 8 and dissolves and extracts monoortho-Co-PCBs adsorbed on the third adsorbent 84. A second aliphatic hydrocarbon solvent from which mono-ortho-Co-PCBs is extracted (hereinafter referred to as a first analysis sample) is secured from the separation column 8 via the fourth path 11 and the first sample discharge path 113. (First securing step).

  Next, the third switching valve 91 is switched so that the separation column 8 and the second sample discharge path 92 communicate with each other, and the fourth switching valve 112 is configured so that the separation column 8 and the third solvent supply path 122 communicate with each other. Switch. Further, the separation column 8 is heated by the heater 82. In this state, the pump 123 is operated, and the aromatic hydrocarbon solvent stored in the third solvent tank 121 is passed through the third solvent supply path 122 and the fourth path 11, and the third adsorbent 84 of the separation column 8. Supply to the side.

  The aromatic hydrocarbon solvent supplied to the separation column 8 is raised by the supply pressure by the pump 123, and the non-ortho Co-PCBs, PCDDs and PCDFs adsorbed on the second adsorbent 83 are dissolved. And extract. Here, the non-ortho Co-PCBs, PCDDs, and PCDFs adsorbed on the second adsorbent 83 are efficiently extracted with a small amount of the aromatic hydrocarbon solvent because the separation column 8 is heated by the heater 82. . An aromatic hydrocarbon solvent (hereinafter referred to as a second analysis sample) from which non-ortho-Co-PCBs, PCDDs and PCDFs have been extracted is secured from the separation column 8 via the third path 9 and the second sample discharge path 92. (Second securing step).

  As a result of the above, according to this analytical sample preparation method, two kinds of dioxin analysis samples, that is, the first sample, are usually collected in a short time of about several hours from the contamination by dioxins contained in the cell 20. An analytical sample (aliphatic hydrocarbon solvent solution of mono-ortho-Co-PCBs) and a second analytical sample (aromatic hydrocarbon solvent solution of non-ortho-Co-PCBs, PCDDs, and PCDFs) can be prepared.

  In addition, since this analytical sample preparation method uses supercritical carbon dioxide in the process of extracting dioxins from contaminated substances by dioxins, it is necessary to use a large amount of hydrophobic solvent such as Soxhlet extraction method. Compared with conventional analytical sample preparation methods, the amount of hydrophobic solvent used can be greatly reduced. Therefore, this analytical sample preparation method has less danger of working environment contamination and environmental contamination due to volatile solvents, and is efficient and economical.

  The first analytical sample obtained by the above-described analytical sample preparation method is usually analyzed qualitatively and quantitatively by GC / MS equipped with a column suitable for the analysis of monoortho-Co-PCBs. On the other hand, the second analysis sample is usually analyzed qualitatively and quantitatively by GC / MS equipped with a column suitable for the analysis of non-ortho Co-PCBs, PCDDs and PCDFs.

[Other embodiments]
(1) In the analytical sample preparation apparatus 1 and the analytical sample preparation method according to the above-described embodiment, supercritical carbon dioxide is used as the supercritical fluid, but a supercritical fluid other than supercritical carbon dioxide, for example, super The present invention can be similarly carried out when critical nitrous oxide is used.

(2) In the analytical sample preparation method according to the above-described embodiment, the second aliphatic hydrocarbon solvent is supplied from the second solvent tank 101 to the fractionation column 8 to secure the first analytical sample. Thereafter, the aromatic hydrocarbon solvent was supplied from the third solvent tank 121 to the fractionation column 8 to secure the second analysis sample, but this order may be reversed. That is, after the aromatic hydrocarbon solvent is supplied from the third solvent tank 121 to the separation column 8 to secure the second analysis sample, the second solvent tank 101 is supplied from the second solvent tank 101 to the separation column 8. An aliphatic hydrocarbon solvent can be supplied to secure a sample for the first analysis.

(3) In the sample preparation device for analysis 1 according to the above-described embodiment, the first sample discharge path 113 and the second sample discharge path 92 may be communicated with individual GC / MS sample introduction sections. Good. In this way, a series of processes from extraction of dioxins from contaminated substances, preparation of two types of analytical samples related to the extracted dioxins, and analysis of the two types of analytical samples by GC / MS The operation can be carried out continuously.

  A filter for collecting dioxins from a fluid (trade name “Dioana (registered trademark)” of Miura Kogyo Co., Ltd.) is impregnated with a predetermined amount of a standard solution of dioxins (including 29 types of dioxins), A test contaminant was prepared. And the sample for analysis of dioxins was prepared from this to-be-contaminated material using the sample preparation device 1 for analysis concerning the above-mentioned embodiment.

At this time, the conditions of the analytical sample preparation apparatus 1 and the analytical sample preparation method were set as follows.
◎ supercritical fluid: supercritical carbon dioxide ◎ first adsorbent 31 of the adsorption column 3: the same filter used in the preparation of the contaminated material ◎ size of the purification column 6: inner diameter 15 mm, length 250 mm
◎ Liquid holding material 61 of purification column 6: silica gel ◎ Purification material 62 of purification column 6: multilayer silica gel in which silver nitrate silica gel and sulfuric acid silica gel are arranged in multiple layers ◎ Size of column 8 for separation: inner diameter 8 mm, length 50 mm
The second adsorbent 83 of the separation column 8: graphite having a specific surface area of 100 m ² / g (trade name “ENVI-Carb”: 120/400 mesh of Sigma-Aldrich) 300 mg
◎ The third adsorbent 84 of the column 8 for separation: 600 mg of graphite having a specific surface area of 250 m ² / g (trade name “ENVI-Carb X”: 120/400 mesh of Sigma-Aldrich)
◎ First aliphatic hydrocarbon solvent: n-hexane ◎ Supply and flow rate of the first aliphatic hydrocarbon solvent to the adsorption column 3 and flow rate: 100 ml, 2.5 ml / min ◎ Second aliphatic hydrocarbon solvent: N-Hexane containing 5% by volume of toluene. The amount and flow rate of the second aliphatic hydrocarbon solvent to the separation column 8 and flow rate: 90 ml, 1.5 ml / min. Aromatic hydrocarbon solvent: toluene. Amount and flow rate of aromatic hydrocarbon solvent to 30 ml, 1.5 ml / min. Heating temperature of column 6 for purification by heater 63: 50 ° C.
◎ Heating temperature of the separation column 8 by the heater 82: 80 ° C.

  Under the above conditions, it took about 3 hours to prepare two kinds of analytical samples. In addition, a first analysis sample (mono-ortho-Co-PCBs aliphatic hydrocarbon solvent solution) from the first sample discharge path 113 and a second analysis sample (non-ortho Co-PCBs, PCDDs) from the second sample discharge path 92. FIG. 2 (results of the first analysis sample) and FIG. 3 (results of the second analysis sample) are analyzed using GC / MS with the aromatic hydrocarbon solvent solution of PCDFs and PCDFs. In each figure, the recovery rate is the ratio (%) of the amount of the dioxin compound contained in each analytical sample to the amount of each dioxin compound contained in the dioxin standard solution. Co-PCBs are displayed according to the IUPAC classification.

  According to FIGS. 2 and 3, almost 100% of the monoortho-Co-PCBs contained in the standard solution of dioxins was contained in the first analysis sample, and was also contained in the standard solution. It can be seen that almost 100% of the non-ortho Co-PCBs, PCDDs and PCDFs are contained in the second analysis sample. From this result, in the sample preparation method for analysis of this example, the dioxins contained in the contaminated substances are classified into two samples: a sample for analysis of mono-ortho-Co-PCBs and a sample for analysis of non-ortho-Co-PCBs, PCDDs, and PCDFs. It can be seen that they were prepared with precise classification.

1 is a schematic view of an embodiment of a sample preparation device for analysis of dioxins according to the present invention. The graph which shows the analysis result of the sample for 1st analysis obtained in the Example. The graph which shows the analysis result of the sample for 2nd analysis obtained in the Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Analytical sample preparation apparatus 2 Extraction part 3 Adsorption column 5 First solvent supply part 6 Purification column 8 Separation column 10 Second solvent supply part 12 Third solvent supply part 31 First adsorbent 83 Second adsorbent 84 Third adsorbent

Claims (4)

A method for preparing a sample for analysis of the dioxins from a contaminated material contaminated with dioxins,
Obtaining an extraction fluid containing the dioxins by bringing a supercritical fluid into contact with the contaminated material;
Contacting the extraction fluid with a first adsorbent capable of adsorbing the dioxins and separating the dioxins from the extraction fluid;
Extracting the dioxins from the first adsorbent using a first aliphatic hydrocarbon solvent to obtain an extract;
A second adsorbent having a specific surface area of 50~180m ² / g, a specific surface area with respect to fractionation column for the third adsorbent is arranged in two layers of 200 to 500 m ² / g, the second adsorbent side Supplying the extract from
A second aliphatic hydrocarbon solvent is supplied from the second adsorbent side to the fractionation column after the extract has passed, and the second aliphatic hydrocarbon solvent that has passed through the fractionation column is A first securing process to secure,
A second securing step of supplying the aromatic hydrocarbon solvent from the third adsorbent side to the fractionation column after the extract has passed, and securing the aromatic hydrocarbon solvent that has passed through the fractionation column. When,
Sample preparation method for analysis of dioxins containing   Before supplying the extract to the fractionation column, the method further includes passing the extract through a purification column filled with a stationary phase capable of capturing a polar substance and not capturing the dioxins. A method for preparing a sample for analysis of dioxins according to claim 1. An apparatus for preparing a sample for analysis of the dioxins from a contaminated material contaminated with dioxins,
An extraction unit for contacting the contaminated material with a supercritical fluid to obtain an extraction fluid containing the dioxins;
An adsorption column packed with a first adsorbent capable of adsorbing the dioxins contained in the extraction fluid;
A first solvent supply unit for supplying a first aliphatic hydrocarbon solvent to the adsorption column;
A second adsorbent having a specific surface area of 50~180m ² / g, specific surface area and a third adsorbent 200 to 500 m ² / g was arranged in two layers, the supplied to the adsorption column a first A separation column capable of receiving the aliphatic hydrocarbon solvent from the second adsorbent side;
A second solvent supply unit capable of supplying a second aliphatic hydrocarbon solvent to the fractionation column from the second adsorbent side;
A third solvent supply unit capable of supplying an aromatic hydrocarbon solvent from the third adsorbent side to the fractionation column;
An apparatus for preparing a sample for analysis of dioxins.   The apparatus further comprises a purification column disposed between the adsorption column and the fractionation column for purifying the first aliphatic hydrocarbon solvent supplied to the adsorption column. 4. An apparatus for preparing a sample for analysis of dioxins according to 3.

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