JP2001342499A - Detergent composition for a member to which a halogenated aromatic compound has adhered, and a cleaning method using the detergent composition - Google Patents

Abstract

(57) [PROBLEMS] To provide a cleaning composition and a cleaning method which are excellent in cleaning performance and have little influence on decomposition treatment of a compound to which a halogenated aromatic compound such as polychlorinated biphenyl is adhered. The purpose is to provide. A halogenated fragrance characterized by containing a saturated hydrocarbon solvent having a boiling point separated from an aprotic polar solvent by 5 ° C. or more and having a boiling point higher than the reaction temperature of the chemical extraction decomposition method. CLEANING COMPOSITION FOR MEMBERS WITH GROUP COMPOUNDS AFFECTED AND CLEANING METHOD

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning composition for a member such as a transformer and a capacitor to which a halogenated aromatic compound such as polychlorinated biphenyl (hereinafter abbreviated as "PCB") is adhered and a treatment method.

[0002]

2. Description of the Related Art Halogenated aromatic compounds such as PCBs are:
Since it has excellent electrical insulation properties, it has been widely used in the past as an electrical insulator such as a transformer and a capacitor. Further, it was widely used as a heat medium, pressure-sensitive paper (registered trademark), and the like. However, due to its high toxicity, halogenated aromatic compounds such as PCBs are currently strictly regulated by law in their production, import and use.

Regarding the treatment of halogenated aromatic compounds such as PCBs, according to the notice on disposal standards for PCBs (Showa 51.3.17 Ring Water Company 38, ring arrangement 18), organic halogenated PCBs and the like are treated. Transformers with aromatic compounds attached, capacitor components, such as steel, copper, aluminum,
In the cleaning treatment of paper, wood, etc., it is specified that the treatment is performed with trichloroethylene, tetrachloroethylene or a cleaning liquid having a detergency equivalent to or higher than these. However, chlorinated organic solvents such as trichloroethylene and tetrachloroethylene are Class 2 specified chemical substances that are suspected to be carcinogenic, and have caused problems such as groundwater contamination. It is becoming difficult to handle except for the use by In addition, there is an environmental problem because it affects the ozone layer.

[0004] Also, n-hexane is known as a cleaner for halogenated aromatic compound contaminants which does not contain chlorine and the like, but has a very low flash point of -26 ° C and a high risk of ignition. There is a problem that it is difficult to use it for purposes other than laboratory-scale applications.

[0005] The present inventors have studied chemical extraction and decomposition of halogenated aromatic compounds for many years, and have found that halogenated aromatic compounds can be converted to aprotic polar compounds such as 1,3-dimethyl-2-imidazolidinone or sulfolane. It has been reported that a halogenated aromatic compound is decomposed by alkali treatment in a solvent (JP-A-6-25691, JP-A-7-8572, JP-A-7-289656, JP-A-9-253602). However,
In the case of cleaning a transformer or the like containing a halogenated aromatic compound as an electric insulator, there is a problem that the cleaning agent adversely affects the alkali treatment. For example, Japanese Patent Application Laid-Open No. H11-106792 proposes a detergent in which β-oxyethyl methyl ether and n-butyl acetate are mixed, and the washing solution after washing is subjected to a decomposition treatment by the chemical extraction decomposition method described above. In this case, the cleaning agent itself reacts, resulting in inhibition of the alkali treatment.

Further, with respect to the waste liquid after the decomposition treatment of the halogenated aromatic compound, it is necessary to measure the concentration of the halogenated aromatic compound and manage it in accordance with laws and regulations. At this time, GC-ECD (Electron Capture Detector Gas Chromatograph) is used as a simple measurement method for the analysis of halogenated aromatic compounds.
Is known to be effective. It is naturally assumed that the waste liquid treated by the chemical extraction decomposition method contains a detergent, but it is desired to introduce a detergent that does not adversely affect the measurement at the time of GC-ECD measurement.

[0007]

DISCLOSURE OF THE INVENTION The present invention relates to a cleaning composition and a cleaning composition which are excellent in cleaning performance and have little influence on the decomposition treatment of a compound to which a halogenated aromatic compound such as PCB is attached. The purpose is to provide a processing method.

[0008]

Means for Solving the Problems By using the cleaning composition of the present invention, the present inventors have found that a member having a halogenated aromatic compound, such as PCB, having excellent cleaning properties and a chemical extraction decomposition can be obtained. The present inventors have found that a cleaning solution having little influence on the decomposition treatment by the method can be obtained, and have completed the present invention.

That is, the present invention provides the following cleaning composition and cleaning method. Item 1. Characterized in that it contains a saturated hydrocarbon-based solvent having a boiling point separated from the aprotic polar solvent by 5 ° C. or more and having a boiling point higher than the reaction temperature of the chemical extraction / decomposition method. A cleaning composition for a member. Item 2. The aprotic polar solvent is 1,3-dimethyl-2-
Item 1. The imidazolidinone, wherein the saturated hydrocarbon solvent is a paraffinic solvent or a naphthenic solvent having a boiling point of at least 205 ° C. and a boiling point of at least 5 ° C. lower than the boiling point of 1,3-dimethyl-2-imidazolidinone. Detergent composition. Item 3. The aprotic polar solvent is 1,3-dimethyl-2-
In imidazolidinone, detergent composition according to claim 1 saturated hydrocarbon solvent is isoparaffin n- dodecane or C ₁₂ -C _13. Item 4. The aprotic polar solvent is 1,3-dimethyl-2-
Item 2. The cleaning composition according to Item 1, wherein the saturated hydrocarbon-based solvent is a naphthene-based solvent having a boiling point of 213 ° C or higher and 215 ° C or lower, which is an imidazolidinone. Item 5. The aprotic polar solvent is 1,3-dimethyl-2-
Item 1. The imidazolidinone, wherein the saturated hydrocarbon solvent is a paraffinic solvent or a naphthenic solvent having a boiling point higher than that of 1,3-dimethyl-2-imidazolidinone by 5 ° C. or more and lower than 270 ° C. Cleaning composition. Item 6. The aprotic polar solvent is 1,3-dimethyl-2-
In imidazolidinone, detergent composition according to claim 1 saturated hydrocarbon solvent is isoparaffin n- tetradecane or C ₁₄ -C _15. Item 7. The aprotic polar solvent is 1,3-dimethyl-2-
Item 2. The cleaning composition according to Item 1, wherein the saturated hydrocarbon-based solvent is a naphthene-based solvent having a boiling point of 240 ° C. or higher and 250 ° C. or lower, which is imidazolidinone. Item 8. The halogenated aromatic compound which dissolves the halogenated aromatic compound attached to the member using the cleaning composition according to any one of Items 1 to 7, and then decomposes the halogenated aromatic compound by a chemical extraction decomposition method. Cleaning method for a member to which is adhered.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Chemical extraction and decomposition methods are disclosed in, for example, JP-A-7-8572 and JP-A-6-25691.

The reaction temperature is appropriately selected depending on the saturated hydrocarbon solvent to be treated, the aprotic polar solvent, the boiling point of the halogenated aromatic compound, etc., and the halogenated aromatic compound such as PCB, the saturated hydrocarbon solvent, and the like. It is less than the lowest temperature of any of the boiling points of the aprotic polar solvent. Usually, the boiling point of a halogenated aromatic compound such as PCB (about 30
0 ° C.) is higher than the boiling point of the saturated hydrocarbon solvent or the aprotic polar solvent, so the upper limit of the reaction temperature is less than the lower temperature of the boiling point of the saturated hydrocarbon solvent or the aprotic polar solvent. is there. The lower limit of the reaction temperature is not particularly limited as long as the reaction is not hindered.
It is preferably at least 00 ° C.

Usually, an aprotic polar solvent used in a chemical extraction decomposition method is more expensive than a saturated hydrocarbon, and therefore, when the halogenated aromatic compound is continuously decomposed, the aprotic polar solvent is used after the decomposition. It is economically advantageous to recover and reuse the aprotic polar solvent from the reaction solution of the above. The method for recovering the aprotic polar solvent from the reaction solution is not particularly limited, but generally a distillation treatment is used.

When the aprotic polar solvent in the reaction solution is recovered by distillation, the boiling point of the saturated hydrocarbon solvent present in the reaction solution together with the aprotic polar solvent is close to the boiling point of the aprotic polar solvent. If so, the recovery rate of the aprotic polar solvent by distillation decreases, which is not desirable.
In consideration of the recovery, it is desirable that the boiling point of the saturated hydrocarbon-based solvent is separated from the boiling point of the aprotic polar solvent by 5 ° C. or more.

For example, as an aprotic polar solvent,
When 1,3-dimethyl-2-imidazolidinone is used, n-tetradecane, as a saturated hydrocarbon solvent having a boiling point higher than that of 1,3-dimethyl-2-imidazolidinone by 5 ° C. or more, C ₁₄ -C ₁₅ isoparaffins, naphthenic solvent having a boiling point of 1,3-dimethyl-2-imidazolidinone higher and lower than 270 ° C. 5 ° C. or higher than the boiling point (in particular naphthenic solvent having a boiling point of 240 to 250 ° C.) Are preferably used. Examples of saturated hydrocarbon solvents having a boiling point lower than that of 1,3-dimethyl-2-imidazolidinone by 5 ° C. or more include n-dodecane and C _12.
~ C ₁₃ isoparaffin, having a boiling point of at least 205 ° C and 1,
A naphthenic solvent having a boiling point of at least 5 ° C. lower than the boiling point of 3-dimethyl-2-imidazolidinone (particularly a naphthenic solvent having a boiling point of 213 to 215 ° C.) is preferably used.

In the present invention, the aprotic polar solvent is not particularly limited as long as the halogenated aromatic compound can be extracted from the non-aromatic hydrocarbon. Preferably, 1,3-dimethyl-2-imidazolidinone, sulfolane, ethylene glycol, diethylene glycol,
It is at least one selected from the group consisting of triethylene glycol, polyethylene glycol, trimethylene glycol, butylene glycol, and lower alkyl ethers thereof. More preferred are 1,3-dimethyl-2-imidazolidinone, sulfolane, and mixtures thereof. More preferably, 1,3-dimethyl-2
-Imidazolidinone. In addition, a low grade has 1 carbon atoms.
~ 5.

The alkaline substance is not particularly limited as long as it does not adversely affect the reaction. Preferably, it is at least one selected from the group consisting of caustic soda, caustic potash, sodium alkoxide, potassium alkoxide and calcium hydroxide.

The reaction time is appropriately selected according to the type of solvent, the reaction temperature, the type and concentration of the halogenated aromatic compound, the type and concentration of the alkaline substance, and the like. For example, in the case of a PCB, it can be decomposed below a quantitative detection limit (0.5 ppm) stipulated by law in several minutes to 6 hours, depending on the processing conditions.

The cleaning composition of the present invention is suitable for cleaning a member to which a halogenated aromatic compound such as PCB is attached. In particular, it is suitable for cleaning transformers, condensers and the like to which halogenated aromatic compounds such as PCB are attached.

The halogenated aromatic compound is not particularly limited, but includes those attached to a transformer, a capacitor, and the like. Preferred is a PCB.

[0020] The cleaning treatment method of the present invention comprises the steps of:
The halogenated aromatic compound is washed by contacting a condenser or the like to extract the halogenated aromatic compound, and the extract is brought into contact with an aprotic polar solvent in the presence of an alkaline substance to decompose the halogenated aromatic compound.

As a method for cleaning transformers, condensers and the like using the cleaning composition of the present invention, washing methods such as immersion, stirring, circulation, rocking, ultrasonic waves, and showers are possible. The preferred cleaning method is the material (material), size,
It is appropriately selected according to the shape, the properties of the contaminants, and the like. In the cleaning of transformers and the like, the size and shape are various, and the materials to be cleaned are also diverse. For this reason, there are cases where the washing can be carried out as it is, and cases where the washing can be carried out after performing processes such as disassembly, crushing, and separation according to the situation.

The method of bringing the treating agent composition of the present invention from which the halogenated aromatic compound has been extracted into contact with an aprotic polar solvent under alkaline conditions is not particularly limited.
Mixing or the like is used. The reaction time, temperature and the like are as described above, and the alkaline substance used is as described above.

[0023]

According to the cleaning composition and the treatment method of the present invention, a member to which a halogenated aromatic compound has adhered has excellent cleaning properties, and can decompose the halogenated aromatic compound.
Reuse of aprotic polar solvents is possible. GC used for measuring the content of halogenated aromatic compound
-Does not adversely affect ECD (Electron Capture Detector Gas Chromatograph) and the like. Therefore, the cleaning composition of the present invention is excellent in cleaning properties of containers and members such as transformers and capacitors to which halogenated aromatic compounds such as PCBs are attached,
It is a cleaning agent that has little effect on the decomposition treatment by the chemical extraction decomposition method. By using the detergent composition, there is no need to use a chlorinated organic solvent such as trichloroethylene or tetrachloroethylene which has an effect on the environment, and by combining with a decomposition treatment by a chemical extraction decomposition method, a halogenated aromatic compound can be obtained. It is possible to treat all group III compounds and components contaminated thereby.

[0024]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the present invention.

[0025] PCB-containing insulating oil adhered member cleaning test (cleaning
Test 1) Example 1 A PCB-containing insulating oil (PCB content of about 1,0) was used as a cleaning solvent with a hydrocarbon-based mixed solvent containing n-dodecane as a main component.
(00 ppm). As a test piece, two pieces of adhesive insulating paper (50 mm × 50 mm) contained in a transformer were used, and each piece was immersed in PCB-containing insulating oil for 24 hours, and then subjected to an immersion ultrasonic cleaning test. Washing was for a maximum of 20 minutes at room temperature. For the measurement of the PCB content contained in the cleaning liquid and in the member, GC-ECD was used, and the cleaning removal rate with respect to the ultrasonic cleaning time was calculated from the initial PCB adhesion amount. The test results are shown in FIG.

Example 2 Calculated in the same manner as in Example 1 except that a naphthenic solvent having a boiling point of 213 to 215 ° C. was used instead of the hydrocarbon-based mixed solvent containing n-dodecane as a main component. The test results are shown in FIG.

Example 3 Calculated in the same manner as in Example 1 except that a hydrocarbon-based mixed solvent mainly containing n-tetradecane was used instead of the hydrocarbon-based mixed solvent mainly containing n-dodecane. The test results are shown in FIG.

Example 4 Calculated in the same manner as in Example 1 except that a naphthenic solvent having a boiling point of 240 to 250 ° C. was used instead of the hydrocarbon-based mixed solution containing n-dodecane as a main component. The test results are shown in FIG.

Comparative Example 1 Calculation was performed in the same manner as in Example 1 except that trichloroethylene (special grade) was used in place of the hydrocarbon-based mixed solvent containing n-dodecane as a main component. The test results are shown in FIGS.

Comparative Example 2 Calculated in the same manner as in Example 1 except that tetrachloroethylene (special grade) was used in place of the hydrocarbon-based mixed solvent containing n-dodecane as a main component. The test results are shown in FIGS.

A cleaning test (a cleaning test)
Experiment 2) Example 5 Using the washing solvent of Example 1 or 2, instead of PCB-containing insulating oil, Kaneklor KC-300 (manufactured by Kaneka Chemical Co., Ltd .: a trichlorinated product widely used for capacitors and the like) Kaneklor KC-1000 (manufactured by Kanegafuchi Chemical Industry Co., Ltd .: Kaneklor K, which is a 5-chlorinated PCB widely used in large transformers and the like)
A mixture of C-500 and 3-chlorinated benzene, PC
B content was about 70% by weight) and the cleaning test was the same as the cleaning test 1 except that the ultrasonic cleaning time was set to a maximum of 60 minutes. It was confirmed that the cleaning solvents used in Examples 1 and 2 had excellent cleaning ability even for high concentration PCBs KC-300 and KC-1000. FIG. 3 shows the test results of KC-300, and FIG. 4 shows the test results of KC-1000.

Example 6 A test was conducted in the same manner as in Example 5 except that the cleaning solvent of Example 3 or 4 was used instead of the cleaning solvent of Example 1 or 2. K
FIG. 5 shows the test results of C-300, and FIG. 6 shows the test results of KC-1000.

Example 7 Confirmation of Influence on Chemical Extraction and Decomposition Method 7 In the chemical extraction and decomposition treatment of KC-300, Example 1,
The effect confirmation test was performed on the assumption that 2, 3, or 4 cleaning solvents were mixed. The decomposition conditions were KC-300 1
0 g, 1,3-dimethyl-2-imidazolidinone in 90
g, 38 g of KOH and 10 g of a washing solvent (Examples 1, 2, 3 or 4) were carried out at a treatment temperature of 200 ° C. and a treatment time of 6 hours. The residual total PCB concentration after the decomposition treatment was measured using high-resolution GC-MS.
As a result, even if the washing solvent used in Example 1, 2, 3 or 4 was mixed, the total PCB concentration remaining was high-resolution GC-M
It was below the detection limit of S (50 ppb or less), and it was confirmed that the cleaning solvent did not adversely affect the decomposition treatment of the halogenated aromatic compound.

Example 8 Example 7 except that KC-300 was replaced with KC-1000.
Same as. As a result, even if the cleaning solvent used in Examples 1, 2, 3, or 4 was mixed, the remaining total PCB concentration was lower than the detection limit of high-resolution GC-MS (50 ppb or lower), and the cleaning solvent was halogenated. It was confirmed that the decomposition treatment of the aromatic compound was not adversely affected.

Analysis method for quantifying halogenated aromatic compounds such as PCBs inhibiting GC-ECD measurement (method using fuming sulfuric acid as pretreatment, reference; "Establishment of rapid analysis method for low chlorinated PCB in insulating oil" Example 1, using environment and measurement technology, Vol.25, No.7 (1998)).
2, 3, or 4 GC-ECD measurements were made. As a result, no specific peak was detected, and it was confirmed that there was no inhibition when performing trace analysis of PCB. The analysis conditions are as follows. Gas chromatography: Hitachi 263-30 Column: OV-17 (2 m) Temperature conditions: 220 ° C (when quantifying 3 chlorinated compounds) and 180 ° C
(When quantifying 1 or 2 chlorinated substances) Pretreatment: The method using fuming sulfuric acid described in the above reference

[0036]

The cleaning composition of the present invention is excellent in cleaning properties of containers and members such as transformers and condensers to which halogenated aromatic compounds such as PCBs are adhered, and has an effect on the decomposition treatment by the chemical extraction decomposition method. It is a low-cleaning agent. By using the detergent composition, there is no need to use a chlorinated organic solvent such as trichloroethylene or tetrachloroethylene which has an effect on the environment, and by combining with a decomposition treatment by a chemical extraction decomposition method, a halogenated aromatic compound can be obtained. It is possible to treat all group III compounds and components contaminated thereby.

[Brief description of the drawings]

FIG. 1 is a graph showing the results of cleaning tests of Examples 1 and 2 and Comparative Examples 1 and 2 with a PCB-containing insulating oil adhered member.

FIG. 2 is a graph showing the results of cleaning tests of Examples 3 and 4 and Comparative Examples 1 and 2 with a PCB-containing insulating oil adhered member.

FIG. 3 shows KC- of the cleaning solvent used in Example 1 or 2.
3 is a graph showing a cleaning effect on 300.

FIG. 4 shows KC- of the cleaning solvent used in Example 1 or 2.
9 is a graph showing a cleaning effect for 1000.

FIG. 5 shows KC- of the cleaning solvent used in Example 3 or 4.
3 is a graph showing a cleaning effect on 300.

FIG. 6 shows KC- of a cleaning solvent used in Example 3 or 4.
9 is a graph showing a cleaning effect for 1000.

Continued on the front page (72) Inventor Tatsuro Amano 1-2-1, Otemachi, Chiyoda-ku, Tokyo Mitsui & Co., Ltd. (72) Inventor Toshiro Tojun 4-1 Egasakicho, Tsurumi-ku, Yokohama-shi, Kanagawa (72) Inventor Hiroshi Wada 1-1, Oike-cho, Kosai-cho, Koga-gun, Shiga Prefecture F-term in NEOS Corporation (reference) 2E191 BA13 BC05 BD11 3B201 AA46 AB01 BB01 BB95 CD22 4H003 DA15 DB01 DC04 ED03 FA45

Claims (8)

[Claims] 1. A halogenated solvent characterized by containing a saturated hydrocarbon solvent having a boiling point separated from the aprotic polar solvent by 5 ° C. or more and having a boiling point higher than the reaction temperature of the chemical extraction decomposition method. A cleaning composition for a member to which an aromatic compound has adhered. 2. The aprotic polar solvent is 1,3-dimethyl-2-imidazolidinone and the saturated hydrocarbon solvent is 20.
The cleaning composition according to claim 1, which is a paraffin-based solvent or a naphthene-based solvent having a boiling point of 5 ° C or more and 5 ° C or more lower than the boiling point of 1,3-dimethyl-2-imidazolidinone. 3. The aprotic polar solvent is 1,3-dimethyl-2-imidazolidinone, and the saturated hydrocarbon solvent is n-
Claim isoparaffins dodecane or C ₁₂ -C ₁₃ 1
9. The cleaning composition according to item 1. 4. The aprotic polar solvent is 1,3-dimethyl-2-imidazolidinone and the saturated hydrocarbon solvent is 21.
The cleaning composition according to claim 1, which is a naphthenic solvent having a boiling point of 3 ° C or more and 215 ° C or less. 5. The aprotic polar solvent is 1,3-dimethyl-2-imidazolidinone, and the saturated hydrocarbon solvent is 1,3-dimethyl-2-imidazolidinone.
The cleaning composition according to claim 1, which is a paraffin-based solvent or a naphthene-based solvent having a boiling point of 5 ° C or higher and lower than 270 ° C than the boiling point of 3-dimethyl-2-imidazolidinone. 6. The aprotic polar solvent is 1,3-dimethyl-2-imidazolidinone, and the saturated hydrocarbon solvent is n-type.
Detergent composition according to claim 1 which is isoparaffin tetradecane or C ₁₄ -C _15. 7. The aprotic polar solvent is 1,3-dimethyl-2-imidazolidinone and the saturated hydrocarbon solvent is 24.
The cleaning composition according to claim 1, which is a naphthenic solvent having a boiling point of 0 ° C or more and 250 ° C or less. 8. After the halogenated aromatic compound attached to the member is dissolved using the cleaning composition according to claim 1, the halogenated aromatic compound is subjected to a decomposition treatment by a chemical extraction decomposition method. A method for cleaning a member to which a halogenated aromatic compound has adhered.