JP2004028739A - Analysis system of hardly decomposable substance - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for analyzing a hardly decomposable substance making it possible to easily measure a content of the substance. <P>SOLUTION: An analyzing system for the hardly decomposable substance to measure the trace content of the substance in a matter to be measured comprises a hydrothermal oxidation treatment means 13 for decomposing the matter 11 containing the substance 12 with allowing the substance to remain and an analyzing means 14 for analyzing the substance 12 remaining as described above. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for analyzing a hardly decomposable substance which can easily measure the content of the hardly decomposable substance in a cleaning test after washing a container containing the hardly decomposable substance such as PCB.
[0002]
[Background Art]
In recent years, the production and import of PCB (Polychlorinated biphenyl, a general term for chlorinated isomers of biphenyl) has been prohibited because of its strong toxicity. Although the production of this PCB began in Japan around 1954, the adverse effects on living organisms and the environment became apparent in the wake of the Kanemi Yusho incident, and in 1972 an instruction was issued to stop production and recall (required storage) due to administrative guidance. There was a background.
[0003]
PCB is obtained by substituting 1 to 10 chlorine atoms in the biphenyl skeleton, and there are theoretically 209 types of isomers depending on the number and positions of the substituted chlorine atoms. The body has been identified. In addition, the physical and chemical properties, in vivo stability, and environmental dynamics of these isomers are diverse, and the current situation is that the chemical analysis of PCBs and the manner of environmental pollution are complicated. Furthermore, PCB is one of the persistent organic pollutants, and has properties that it is not easily decomposed in the environment, is fat-soluble, has a high bioconcentration rate, is semi-volatile, and can be moved through the atmosphere. In addition, it is reported that it remains widely in the environment such as water and living things.
As a result, since PCB is extremely stable in the body, it is accumulated in the body and causes chronic poisoning (skin damage, liver damage, etc.), and carcinogenicity and reproductive / developmental toxicity are recognized.
[0004]
Since PCBs have been widely used as insulating oils for transformers and capacitors, it is necessary to treat PCBs.
[0005]
At present, various methods for treating PCB have been proposed and detoxification has been carried out. However, the PCB from which the liquid has been drained removes the PCB by, for example, washing means.
[0006]
By the way, there is a problem that it takes one to two days, time and effort to determine whether or not the above-mentioned cleaning process has reached a specified cleaning standard in the current method of measuring PCB. That is, the solvent is extracted from the washing solution, the target PCB is concentrated, and water is added after partitioning between acetonitrile and hexane. After that, it is necessary to take a technique of extracting with hexane, performing a sulfuric acid treatment, performing chromatography, separating a PCB, and then performing GC analysis.
[0007]
As a method for measuring the cleaning liquid, there is a GC-MS means. This method has an advantage that organic compounds can be detected in general, but there is an advantage that impurities such as insulating oil such as PCB-contaminated oil are present. In addition, when ionized, there is a problem that the PCB cannot be quantified due to interference with the insulating oil or the like.
[0008]
Although there is a GC-ECD means, it has an advantage that organic halides can be selectively detected, but when impurities such as insulating oil are present at a high concentration, the detector is contaminated. Therefore, there is a problem that the durability of the detecting means is deteriorated.
[0009]
Further, there is a method of quantifying only Cl, such as a Cl combustion method. In this case, analysis cannot be performed unless Cl is a single substance, and when there are 209 isomers such as PCB, the like. However, there is a problem that accurate quantification cannot be performed.
[0010]
The present invention has been made in view of the above-described problems, and provides a method for analyzing a hardly decomposable substance that can easily measure the content of a harmful substance in a cleaning test after washing a container containing a hardly decomposable substance such as PCB. As an issue.
[0011]
[Means for Solving the Problems]
A first invention for solving the above-mentioned problem is an analysis system for a hardly decomposable substance for measuring a trace amount of a hardly decomposable substance in an object to be measured,
When decomposing an object to be measured containing a hardly decomposable substance, a hydrothermal oxidation means for decomposing while remaining the hardly decomposable substance,
An analysis system for a hardly decomposable substance, comprising an analysis means for analyzing the remaining hardly decomposable substance.
[0012]
In a second aspect, in the first aspect,
The above-mentioned hydrothermal oxidation treatment means is characterized in that the decomposition treatment temperature is 300 to 380 ° C and the pressure is 22 to 26 MPa.
[0013]
In a third aspect, in the first aspect,
The hydrothermal oxidation means is a batch-type decomposition treatment means or a continuous decomposition-type decomposition treatment means.
[0014]
In a fourth aspect based on the first aspect,
In the analysis system for a hardly decomposable substance, the hardly decomposable substance is PCB.
[0015]
In a fifth aspect based on the first aspect,
In the analysis system for hardly decomposable substances, the analysis means includes a solid phase extraction means.
[0016]
According to a sixth aspect, in the fifth aspect,
In the invention of the solid phase extraction means, there is provided a system for analyzing a hardly decomposable substance, wherein the extraction solvent is n-hexane.
[0017]
According to a seventh aspect, in the first aspect,
The object to be measured is any one of insulating oil, water, slurry, paper, wood, fiber, solvent, soil, paint, resin, ceramics, metal, blood, and organism, and contains a trace amount of PCB. It is in the analysis system for persistent substances.
[0018]
An eighth invention is a method for analyzing a hardly decomposable substance for measuring a trace amount of a hardly decomposable substance in an object,
When decomposing an object to be measured containing a hardly decomposable substance using hydrothermal oxidative decomposition processing means, a hydrothermal decomposition step of decomposing while remaining the hardly decomposable substance,
An analysis step of analyzing the remaining hardly decomposable substance.
[0019]
The ninth invention is based on the first invention,
In the method for analyzing a hardly decomposable substance, the decomposition temperature of the hydrothermal oxidation step is 300 to 380 ° C and the pressure is 22 to 26 MPa.
[0020]
In a tenth aspect based on the eighth aspect,
The method for analyzing a hardly decomposable substance is characterized in that the hydrothermal oxidation means is a batch decomposition method or a continuous decomposition method.
[0021]
An eleventh invention is based on the eighth invention,
In the method for analyzing a hardly decomposable substance, the hardly decomposable substance is PCB.
[0022]
In a twelfth aspect, in the eighth aspect,
In the method for analyzing a hardly decomposable substance, the analysis step includes a solid phase extraction step.
[0023]
A thirteenth invention is the twelfth invention,
In the invention of the solid phase extraction step, there is provided a method for analyzing a hardly decomposable substance, wherein the extraction solvent is n-hexane.
[0024]
According to a fourteenth aspect, in the eighth aspect,
The object to be measured is any one of insulating oil, water, slurry, paper, wood, fiber, solvent, soil, paint, resin, ceramics, metal, blood, and organism, and contains a trace amount of PCB. It is in the method of analyzing persistent substances.
[0025]
BEST MODE FOR CARRYING OUT THE INVENTION
Embodiments of the present invention will be described below, but the present invention is not limited to these embodiments.
[0026]
The system 10 for analyzing a hardly decomposable substance according to the present embodiment is a system for analyzing a hardly decomposable substance that measures the concentration of a trace amount of a hardly decomposable substance in an object to be measured. When decomposing, hydrothermal oxidation treatment means 13 for decomposing while remaining the hardly decomposable substance 12,
And analysis means 14 for analyzing the remaining hardly decomposable substance 12.
An oxidizing agent 15 is supplied to the hydrothermal oxidative decomposition treatment means 13 to decompose organic compounds by hydrothermal oxidative decomposition at high temperature and high pressure.
In other words, as a pretreatment before the analysis, the hydrothermal oxidation treatment means 13 is used to perform hydrothermal oxidative decomposition under a subcritical state while remaining the hardly decomposable substance 12 in the object 11 to be measured. It is possible to decompose an organic compound (analyte-interfering substance) other than PCB, for example, a hardly decomposable substance 12, and the insulating oil, which is a contaminant of PCB, disappears. Therefore, only the remaining PCB is analyzed. Fast, high-precision analysis becomes possible.
[0027]
Here, in the hydrothermal oxidation treatment means 13, the decomposition treatment conditions are preferably such that the decomposition treatment temperature is 300 to 380 ° C and the pressure is 22 to 26 MPa. This is because PCB which is a hardly decomposable substance remains, and other organic compounds are decomposed.
The presence of a dechlorinating agent such as sodium hydroxide (NaOH) and sodium carbonate (Na ₂ CO ₃ ) is not preferable because it is completely decomposed.
[0028]
The hydrothermal oxidation treatment means 13 may be either a batch decomposition treatment means or a continuous decomposition treatment means.
[0029]
In the present invention, as the hardly decomposable substance 12, for example, PCB can be exemplified, but it is not limited to PCB, and any substance may be used as long as it is not decomposed under the above hydrothermal oxidative decomposition treatment conditions.
[0030]
In the above hydrothermal oxidative decomposition treatment, after the decomposition treatment while remaining the hardly decomposable substance, the analyzing means 14 uses a means for extracting the hardly decomposable substance such as a solid-phase extraction means 16, for example. The concentration of the substance 12 may be performed.
The decomposition product 17 from the hydrothermal oxidation means 13 supplied to the solid phase extraction means 16 has been cooled by the cooling means 18 in advance.
[0031]
As the extraction solvent used in the solid phase extraction means 18, for example, an extraction solvent of n-hexane can be used.
[0032]
In the present invention, as the sample 11 to be measured, as shown in FIG. 2, for example, insulating oil, water, slurry, paper, wood, fiber, solvent, soil, paint, resin, ceramics, metal, blood, organism, etc. Can be exemplified, but the present invention is not limited to these.
[0033]
Note that, depending on the analysis target, a slurrying means 41, a solvent extracting means 42, or the like may be used.
The case where the slurrying means 41 is used is, for example, a case where a hardly decomposable substance in paper, wood, fiber or the like is measured.
The case where the solvent extracting means 22 is used is, for example, a case where a solvent, soil, paint, resin, ceramics, metal, blood, and a hardly decomposable substance in an organism are measured.
[0034]
Hereinafter, in the present embodiment, a description will be given by taking a PCB which is a hardly decomposable substance 12 as an example, but the present invention is not limited to this.
[0035]
Here, as the apparatus for the oxidative decomposition treatment, a hydrothermal oxidative decomposition apparatus that decomposes organic compounds into carbon dioxide (CO ₂ ) or the like by an oxidative decomposition reaction in a heated and pressurized reactor is used.
[0036]
According to the above-mentioned hydrothermal decomposition means 13, PCB which is a hardly decomposable substance is not decomposed as it is, but other organic compounds are decomposed by hydrothermal oxidation.
FIG. 4 shows the relationship between the decomposition time and the residual ratio.
As shown in FIG. 4, it was found that PCB which is a hardly decomposable substance was intact, but organic compounds such as insulating oil were decomposed with time.
As shown in FIG. 4, after 1 minute, the residual ratio of the insulating oil was 1% or less, and even when this was analyzed, no obstructive effect of the analysis was observed.
[0037]
As shown in FIG. 4 (A), the solid phase / adsorbing means 12 has a solid phase adsorbent 22 inserted into an extraction column 21. The solid phase adsorbent is made of silica gel or alumina. ing.
[0038]
Silica gel or alumina was selected as the solid phase adsorbent 22 because it is suitable to efficiently adsorb and separate organic halides.
[0039]
The eluent 16 that elutes the organic halide held by the solid-phase adsorbent is not particularly limited as long as it is a solvent that elutes only the target organic halide. For example, when the organic halide is PCB, Examples thereof include non-polar solvents (for example, n-hexane), alcohols (for example, methyl alcohol and ethyl alcohol), toluene, dichloromethane, and acetonitrile. In particular, it is preferable to use n-hexane from the relation with the detector.
[0040]
Further, since it is necessary to monitor the wastewater at predetermined time intervals, a sample introducing means for periodically introducing a collected sample is provided to enable automatic sampling.
[0041]
In order to improve the analysis accuracy, if several samples are to be simultaneously performed at the same time as necessary, a plurality of the columns 21 are prepared, and the organic halide is solid-phased and adsorbed simultaneously. You may.
[0042]
Hereinafter, the extraction process of the solid phase / adsorption means 12 will be described with reference to FIGS.
{Circle around (1)} Conditioning Step In order to obtain a result with good reproducibility, the conditioning liquid 31 is supplied to the solid-phase adsorbent 22 before supplying the sample, and the conditioning is performed (see FIG. 4A).
(2) Holding Step Next, the sample 32 is introduced into the column 21 (see FIG. 4B). Here, it is assumed that the sample contains the PCB 33 as the target substance, the impurity X (unnecessary matrix), and the impurity Y (the other components in the matrix).
(3) Washing step Next, the impurities X retained in the solid-phase adsorbent 22 are washed away with a washing liquid (for example, methyl alcohol) (see FIG. 4C).
{Circle over (4)} Elution Step Next, the target substance PCB 33 held by the solid-phase adsorbent 22 is eluted with an eluent (n-hexane) 35. During this elution, the impurity Y remains in the solid phase adsorbent 22 and is separated from the PCB 33 (see FIG. 4D).
[0043]
FIG. 5 shows a process chart of solid-phase extraction using the above-mentioned organic halide detector.
{Circle around (1)} First, 20 mL of n-hexane is supplied to the solid phase adsorbent 22, and solid phase drying (evacuating) is performed for 5 minutes (S101).
{Circle over (2)} After flowing 20 mL of methyl alcohol and 20 mL of ultrapure water, a sample (0.1 to 1 L) is introduced, the PCB is collected, and solid phase extraction is performed (S102).
At this time, 1% of methyl alcohol was added to the sample. This addition of methyl alcohol has the function of dispersing the PCB.
{Circle around (3)} After that, 5 mL of a washing liquid (methyl alcohol) is flowed (flow rate: 0.3 cc / s) to wash (S103).
{Circle around (4)} Thereafter, the solid-phase adsorbent 22 is dried (evacuated) for 5 minutes (S104).
{Circle around (5)} Thereafter, the PCB is eluted with n-hexane at a flow rate of 0.3 cc / s (S105), and the volume is adjusted to 5 mL (S106).
{Circle around (6)} Next, 1 to 5 μl is analyzed by any one of analyzers such as a gas chromatograph analyzer (GC) or a liquid chromatograph analyzer (LC), an ultraviolet absorption spectrophotometer (UV), and an atomic absorption / emission analyzer. (S107), the PCB concentration is measured (S108).
{Circle around (7)} The column from which the PCB has been eluted can be backwashed with a mixture of n-hexane and acetone (1: 1), regenerated, and then subjected to PCB measurement again.
[0044]
Next, FIG. 6 shows an example of an analysis process using the batch type hydrothermal oxidative decomposition treatment apparatus.
As shown in FIG. 6, the hydrothermal oxidative decomposition treatment means 13 is supplied with the sample 11 containing the hardly decomposable substance 12 to be analyzed, the water 20 and the oxidizing agent 15 therein. I have.
[0045]
When the insulating oil containing PCB is decomposed, the hydrothermal oxidative decomposition treatment means 13 is decomposed by setting the temperature to 300 ° C. to 380 ° C., the pressure to 22 to 26.5 MPa, and the decomposition time to about 1 to 5 minutes. ing.
[0046]
Next, after the decomposition, the hexane solution 50 is supplied, and only the PCB is transferred to the hexane solution side.
[0047]
Next, the hexane solution is extracted and analyzed, so that the concentration of the PCB is measured by the analysis means 14.
[0048]
Next, an example of an analysis process using the continuous hydrothermal oxidative decomposition treatment apparatus is shown in FIG.
As shown in FIG. 7, the sample 11 to be analyzed, the water 20 and the oxidizing agent 15 are supplied to the hydrothermal oxidative decomposition treatment means 13.
[0049]
When the insulating oil containing PCB is decomposed, the hydrothermal oxidative decomposition treatment means 13 is decomposed by setting the temperature to 300 ° C. to 380 ° C., the pressure to 22 to 26.5 MPa, and the decomposition time to about 1 to 5 minutes. ing.
[0050]
Next, after the decomposed decomposition product 51 is cooled by the cooling means 18, the hexane solution 50 is supplied, and only the PCB is transferred to the hexane solution side by the PCB extraction means (stirring or mixing) 51.
[0051]
Next, the hexane solution and the wastewater are separated, and the concentration of PCB in the hexane solution is measured by the analysis means 14.
[0052]
In the present invention, examples of the harmful substance include, but are not limited to, PCB, paint containing PCB, PCB contaminants, etc., which are insulating oils used in transformers and capacitors.
[0053]
【The invention's effect】
As described above, according to the present invention, the oxidative decomposition treatment is performed under the subcritical condition at the decomposition temperature of 300 to 380 ° C. and the pressure of 22 to 26 MPa. Oxidative decomposition of the analyte containing decomposable substances will be performed, and easily decomposable organic substances will be decomposed, but only hardly decomposable substances will remain, enabling rapid and accurate analysis of trace components. It becomes.
[Brief description of the drawings]
FIG. 1 is a schematic diagram of a hydrothermal oxidative decomposition device according to the present embodiment.
FIG. 2 is a schematic diagram of a hydrothermal oxidative decomposition device according to the present embodiment.
FIG. 3 is a diagram showing the relationship between the decomposition time of PCB and insulating oil and the residual ratio.
FIG. 4 is a drawing illustrating an extraction process of a solid phase / adsorption means.
FIG. 5 shows a process chart of solid-phase extraction.
FIG. 6 is an analysis process diagram using a batch type hydrothermal oxidative decomposition treatment apparatus.
FIG. 7 is an analysis process diagram using a continuous hydrothermal oxidative decomposition treatment apparatus.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Analysis system of hardly decomposable substance 11 DUT 12 Hardly decomposable substance 13 Hydrothermal oxidation treatment means 14 Analysis means 15 Oxidant

Claims (14)

An analysis system for a hardly decomposable substance that measures a trace amount of a hardly decomposable substance in an object,
When decomposing an object to be measured containing a hardly decomposable substance, a hydrothermal oxidation means for decomposing while remaining the hardly decomposable substance,
An analysis system for a hardly decomposable substance, comprising an analysis means for analyzing the remaining hardly decomposable substance. In claim 1,
An analysis system for a hardly decomposable substance, wherein the hydrothermal oxidation treatment means performs an oxidative decomposition treatment at a decomposition treatment temperature of 300 to 380 ° C and a pressure of 22 to 26 MPa. In claim 1,
An analysis system for a hardly decomposable substance, wherein the hydrothermal oxidation means is a batch type decomposition treatment means or a continuous decomposition type decomposition treatment means. In claim 1,
An analysis system for a hardly decomposable substance, wherein the hardly decomposable substance is PCB. In claim 1,
An analysis system for a hardly decomposable substance, wherein the analysis means includes a solid phase extraction means. In claim 5,
An analysis system for a hardly decomposable substance, wherein the extraction solvent is n-hexane in the solid phase extraction means. In claim 1,
The object to be measured is any one of insulating oil, water, slurry, paper, wood, fiber, solvent, soil, paint, resin, ceramics, metal, blood, and organisms, and contains a trace amount of PCB. Analysis system for persistent substances. An analysis method for a hardly decomposable substance for measuring a trace amount of a hardly decomposable substance in an analyte,
When decomposing an object to be measured containing a hardly decomposable substance using hydrothermal oxidative decomposition processing means, a hydrothermal decomposition process step of decomposing while remaining the hardly decomposable substance,
An analysis step of analyzing the remaining hardly decomposable substance. In claim 1,
An analysis method for a hardly decomposable substance, wherein the decomposition temperature in the hydrothermal oxidation step is 300 to 380 ° C and the pressure is 22 to 26 MPa. In claim 8,
The method for analyzing a hardly decomposable substance, wherein the hydrothermal oxidation means is a batch type decomposition treatment means or a continuous decomposition type decomposition treatment means. In claim 8,
A method for analyzing a hardly decomposable substance, wherein the hardly decomposable substance is PCB. In claim 8,
An analysis method for a hardly decomposable substance, wherein the analysis step includes a solid phase extraction step. In claim 12,
The method for analyzing a hardly decomposable substance, wherein the extraction solvent is n-hexane in the solid phase extraction step. In claim 8,
The object to be measured is any one of insulating oil, water, slurry, paper, wood, fiber, solvent, soil, paint, resin, ceramics, metal, blood, and organisms, and contains a trace amount of PCB. Analysis method for persistent substances.

Images