JPH08229385A - Decomposing method of hardly decomposable organic chlorine compound and new microorganism - Google Patents

Abstract

PURPOSE: To completely decompose an organic chlorine compound without generating harmful material. CONSTITUTION: A hardly decomposable organic halogen compound is dissolved in an organic solvent, photochemically treated to execute dechlorination reaction by irradiating with energy of <=250nm wavelength and after that, biologically treated with a microorganism capable of decomposing at least one part of the organic chlorine compound to decompose the residual organic chlorine compound. As a result, a large quantity of the energy like in a combustion treatment is not necessary since the reaction is executed under ordinary temp. and normal pressure.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for decomposing a hardly decomposable compound, and more particularly to a method for decomposing an organic chlorine compound as an alternative to a combustion method.

[0002]

2. Description of the Related Art There are various substances chemically synthesized, and among them, substances that are difficult to decompose are included, and there are many substances whose treatment methods have not been established. Many of them are those that may destroy the natural environment and those that are anxious about their effects on the human body, and the establishment of a safe disposal method for them is an urgent issue.

A typical example of the hardly decomposable compound is an organic chlorine compound. Conventionally, various organic chlorine compounds have been used as pesticides and the like, and there is a concern about the effects on the human body such as soil pollution and agricultural crop pollution. For example,
Known insecticides are DDT and its analogs such as dieldrin and hexachlorocyclohexane.

Tetrachloroethylene and trichloroethylene are widely used as organic chlorine solvents, and are used as a detergent in a dry cleaning plant or for removing grease in microchip production. Further, chloroform, carbon tetrachloride, methylene chloride and the like are also used industrially.

Since the above-mentioned organic chlorine compounds are generally not easily decomposed by bacteria, many of them remain in the environment for a long time. Further, these are not only difficult to decompose and difficult to process, but there is a problem that when they are burned, some toxic substances are produced. For example, it is known that when an organic chlorine compound is burned at a low temperature, a large amount of extremely toxic dioxin is produced. Therefore, in the treatment of organic chlorine compounds, combustion treatment is carried out in a high-temperature combustion furnace specializing in hazardous waste under strict pollution regulations.

[0006]

As described above, organic chlorine compounds are not completely decomposed unless they are incinerated at high temperatures. Therefore, when organic chlorine compounds are burnt, high-temperature combustion specialized for large-scale hazardous waste is required. A furnace and cooling system are required. However, the construction of such processing equipment is
It is costly and difficult to obtain social consent for construction. Furthermore, in the combustion treatment of organic chlorine compounds, it is necessary to continuously monitor whether highly toxic substances such as dioxins are generated during the treatment period. However, the combustion method has a problem in that it cannot predict all the substances that may be generated after combustion. That is, combustion may produce an unknown toxic compound.

Therefore, it is desired to establish a method for decomposing organic chlorine compounds instead of the combustion method. Here, as an alternative treatment method, it is desired that the target organic chlorine compound is completely decomposed, all the substances that may be generated during and after the treatment can be grasped, and their safety can be confirmed. That is, it is important to decompose the target organic chlorine compound by a highly specific decomposition reaction.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method for decomposing an organic chlorine compound which can completely decompose the organic chlorine compound without producing a harmful substance.

[0009]

The method for decomposing a hardly decomposable organochlorine compound according to the present invention comprises a photochemical treatment for irradiating an energy beam having a wavelength of 250 nm or less to a dechlorination reaction to cause a dechlorination reaction. It is characterized in that a microorganism treatment for decomposing the remaining organic chlorine compound is carried out by a microorganism capable of decomposing at least a part of the organic chlorine compound. In the photochemical treatment, it is preferable that the hardly decomposable organochlorine compound is dissolved in an organic solvent and irradiated with ultraviolet rays. Polychlorinated biphenyls can be used as the organic chlorine compound.

It is preferable that the above microorganism has a property of decomposing at least the above organic chlorine compound having a chlorine substitution number of 3 or less. Examples of the microorganism include Pseudomonas alcaligenes TK102,
Or Pseudomonas Supishiizu (Pseudomonas sp
ecies) KKS102 is preferably used.

Pseudomonas Alcaligenes T
K102 has already been deposited by the present applicant at the Institute of Biotechnology, Institute of Biotechnology, and the deposit number is FERM P.
-14591.

Also, Pseudomonas species KK
S102 has already been deposited at the Institute of Microbial Technology of the Agency of Industrial Science and Technology, and the deposit number is FERM P-9354.

[0013]

[Function] Generally, photochemical reaction and microbial reaction have high specificity, and the reaction products are determined, so that they are considered to be suitable for the treatment of persistent substances.

However, when the photochemical treatment or the microbial treatment is applied to the decomposition of the organic chlorine compound alone, it is difficult to completely decompose the organic chlorine compound. That is, in the photochemical treatment, it is possible to reduce the number of substituted chlorine in the organochlorine compound, but it is difficult to completely remove chlorine, and in the microbial treatment, even with a microorganism having a high activity of degrading the organochlorine compound, There is a problem that an organic chlorine compound having a large number of substituted chlorine cannot be decomposed.

In the method for decomposing an organochlorine compound according to the present invention, a highly specific photochemical reaction and a microbial reaction are combined so that the desired organochlorine compound is first converted to the number of substituted chlorines that can be decomposed by the microorganism by photochemical treatment. It is dechlorinated and then completely decomposed by a microorganism having a high activity of decomposing organic chlorine compounds. Here, in photochemical treatment, only chlorine is liberated from the organic chlorine compound, and no harmful substance is generated. The chlorine is recovered as hydrochloric acid.

The decomposition of organochlorine compounds by microorganisms is specific to the enzymatic reaction, and it has been clarified along with the intermediate products and final products thereof, and there is no problem regarding the safety thereof. Here, as the above microorganism, the number of substituted chlorine is 3
It is preferable to use one having the ability to decompose the following organic chlorine compounds, for example, an organic compound serving as a mother nucleus,
That is, a microorganism capable of degrading an organic chlorine compound having a small number of substituted chlorines can be selected and used from microorganisms capable of efficiently assimilating an organic compound having a substituted chlorine number of 0.

[0017]

[Examples] Polychlorinated biphenyl (hereinafter referred to as PCB
The preferred embodiment of the present invention will be described in detail below.

Generally, PCBs dissolved in a solvent are exposed to UV light,
When irradiated with light such as X-rays and γ-rays, radicals are generated from the solvent, whereby chlorine atoms are replaced with hydrogen atoms, and the number of chlorine atoms substituted in the PCB can be reduced. The release of chlorine at this time is characteristic in that chlorine substituted at the ortho position is released most efficiently, and chlorine at other positions is difficult to release.

On the other hand, biphenyl or PC by microorganisms
In the decomposition route of B, as shown in FIG. 1, carbons at positions 2 and 3 of one aromatic ring are oxidized (FIGS. 1B and C), and then carbon bonds at positions 1 and 2 are broken and cleaved ( FIG. 1D).
Microorganisms are well decomposed by PCB congeners having chlorine substitution at positions other than the ortho positions, but PCBs having chlorine substitution at the ortho positions are less susceptible to decomposition by microorganisms even if the number of substitutions is small.

Therefore, it is thought that it is possible to assist the decomposition of PCB by microorganisms by pre-treating PCBs photochemically, and when photochemical treatment and microbial treatment are combined, PCBs with a high chlorine number are completely decomposed. Then, they have completed the present invention.

Here, the PCB to be decomposed is not limited in the chlorine addition position, the number of chlorine added, etc. Therefore, it can be subjected to the decomposition as it is as a mixture which is a usual existence form.

First, in order to photochemically treat the PCB, the decomposed PCB is dissolved in a solvent to prepare a PCB solution. As the solvent at this time, methanol, ethanol, acetone, octane or the like is preferably used. Also, 60 to 10
0.01-2% in 0% methanol or ethanol
The one added with NaOH or KOH is preferably used, and about 70% methanol or ethanol is added with 2%.
Those to which about NaOH or KOH is added are particularly preferably used. Here, the concentration of the PCB solution is 10 to 1
0000 ppm, preferably 500-1000 ppm
And

Next, this PCB solution is subjected to photochemical treatment. The energy ray for photochemical treatment has a wavelength of 2
Energy rays of 50 nm or less may be used, and ultraviolet rays, X
Energy rays such as rays and γ rays can be used,
Ultraviolet rays are most preferably used in terms of practicality. Next, the PCB solution is placed in a container which is preferably sealable and transparent to the radiation and energy rays used. When ultraviolet rays are used as the above-mentioned energy rays, preferably 1 to 10 mW / cm ² , preferably 3 to 6 mW / cm ² of ultraviolet rays are irradiated in an amount of 1 to 1 in a transparent container such as quartz glass.
Irradiate for 00 hours, preferably 10 to 24 hours. By this photochemical treatment, PCB becomes less than 3 chlorine substituted, and all ortho chlorine is substituted by hydrogen.

Next, the PCB solution after the ultraviolet ray treatment is taken out and subjected to the following microorganism treatment step. The microorganisms used in the microorganism treatment process include biphenyl and PCB.
Phanerochaete chrysospum ( Phanerochaete chrysospum ) belonging to the genus Pseudomonas, Rhodococcus, Alcaligenes, Bacillus, or white-rot fungus
Microorganisms such as molds such as orlum ) can be used, but Pseudomonas bacteria with high biphenyl and PCB decomposing activity are particularly preferably used. For example, Pseudomonas alcaligenes TK102 and Pseudomonas species KKS102 are preferably used.

The mycological properties of TK102 and KKS102 were determined by the general method for identifying bacteria (BERGEY'S MANUAL OF Syste).
According to the test items in matic Bacteriology vol.1 (1984)), it is as follows. Here, flagella staining was performed by Mayfield et al., Can. J. Microbiol 23, 1311 (1977).
GC content analysis and quinone molecular species identification were performed according to Katayama-Fujimura et al., J. Gen. Microbiol., 12
8 , 1599 (1982) and Katayama-Fujimura et al., Agric. Bi
ol. Chem., 48 , 3169 (1984).

TK102 KKS102 Gram stain- (KOH test +)-morphology Bacillus bacillus spores-Mobility Not observed + morphology of flagella polar colonies Light lemon yellow Slightly translucent round, regular, full-edged, shiny, smooth, low Low convex 48 hours later Approximately 0.5 mm in diameter Growth at 37 ° C (+) (weak) Growth at 41 ° C-Growth at 45 ° C-Catalase ++ oxidase ++ Fermentability in glucose OF test (Fermentative) − −

The TK102 KKS102 30 ℃, reduction of 48 hours Nitrate - + dye forming - G + C content mol% 67.02 generation molecular species Q ₈ of indole quinone - Acid from glucose - Arginine dihydrolase - Urease - decomposition of esculin + Degradation of gelatin-β-galactosidase + glucose assimilation + arabinose assimilation (+) (weak) Mannose assimilation-mannitol assimilation-N-acetylglucosamine assimilation (+) (weak) maltose assimilation + caproic acid assimilation-adipate assimilation- Maleic acid assimilation + Citrate assimilation + Phenylacetic acid assimilation-Cytochrome oxidase +

TK102 30 ° C., 7 days Casein decomposition-Tween80 decomposition-Starch decomposition-DNase production + (limited area of decomposition) Tyrosine decomposition (+) Acid from lactose OF medium-Acid from maltose OF medium-Lactose PWS ( Acid from peptone water sugar) -Acid from maltose PWS (peptone water sugar) -Acid from low peptone maltose medium +

[0029]

Based on the above properties, TK102 was identified as Pseudomonas alcaligenes and KKS102 was identified as Pseudomonas species.

The above-mentioned microorganism is added to, for example, 1 to 10,000 p
pm, preferably in a minimum medium containing 1000 to 3000 ppm of biphenyl as a single carbon source, 20 to 37 ° C., preferably 25 to 30 ° C., 1 to 14 days, preferably 4 to
Seed culture for 7 days. Then, for example, 1 to 10000p
10 to 1000 ppm, preferably 100, of the above-mentioned photochemically treated PCB is added to a minimum medium containing pm, preferably 1000 to 3000 ppm of biphenyl as a single carbon source.
After inoculating the culture solution after the above-mentioned culture to the one added so as to have a concentration of ~ 500 ppm, shaking or stirring is performed at 20 to 37 ° C, preferably 25 to 30 ° C for 1 to 14 days, preferably 4 to 7 days. Incubate.

For culturing the Pseudomonas bacteria, for example, 1.7 g / l KH ₂ PO ₄ , 9.8 g / l
l Na ₂ HPO ₄ , 1.0 g / l (NH 4) ₂ SO ₄ ,
0.1 g / l MgSO ₄ / 7H ₂ O, 0.95 mg / l
FeSO ₄ .7H ₂ O, 10.75 mg / l MgO,
2.0 mg / l CaCO ₃ , 1.44 mg / l Zn
SO ₄ · 7H ₂ O, CuSO of 0.25mg / l ₄ · 5H ₂
O, 0.28 mg / l CoSO ₄ / 7H ₂ O, 0.06
A medium having a composition containing mg / l H ₃ BO ₃ , 51.3 ml / l concentrated HCl, and biphenyl as a single carbon source can be preferably used as the minimum medium.

Although most of the PCB congeners are decomposed by the above-mentioned microbial treatment, it is preferable to monitor in order to confirm the degree of PCB decomposition.

As a method of monitoring the degree of decomposition of PCB, for example, the culture solution treated with the above microorganisms may be subjected to extraction of residual PCB with a solvent such as ethyl acetate, followed by analysis by gas chromatography mass spectrometry (GCMS). .

Example 1 Examination of Photochemical Treatment Conditions PC actually used as insulating oil for transformers
B, Kanechlor 500 was dissolved in methanol to make 2 ml of a solution having a concentration of 0.2% by volume, and the solution was placed in a cell with a screw cap made of quartz glass, which was irradiated with ultraviolet rays from a mercury lamp for 26 hours, and then treated with ultraviolet rays. Was performed (energy density 3 mW / cm ² ). Samples after 3, 5, 15, and 26 hours of irradiation with ultraviolet rays were sampled, and the state of decomposition was examined by gas chromatography. A gas chromatography chart is shown in FIG.

FIG. 2A shows the results of analysis of the untreated PCB.
Many peaks are seen between 35 and 55 minutes, indicating the presence of congeners with 4 to 6 chlorine substitutions added at various positions. The peak gradually shifted to the left after 3 hours (Fig. 2B), 5 hours (Fig. 2C), and 15 hours (Fig. 2D) of UV irradiation, and the dechlorination reaction of PCB proceeded. I was able to confirm that Then, 26 hours after UV irradiation (FIG. 2E), peaks were concentrated in almost three places. The three places show the number of chlorine molecule substitutions = 0, 1, 2 from the left. Therefore, it was confirmed that 26 hours after the irradiation with ultraviolet rays, the PCB contained only the congener having a chlorine substitution number of 2 or less, and a sufficient photochemical reaction proceeded.

Example 2-Study of Solvent in Photochemical Treatment As the solvent for dissolving PCB, octane, ethanol, and acetone were used instead of methanol, and the ultraviolet ray treatment was carried out for 26 hours in the same manner as in Example 1. went. The result is shown in FIG. 26 with any solvent of octane (FIG. 3A), ethanol (FIG. 3B), and acetone (FIG. 3C).
It can be seen that the peak of the congener with the number of 4-substituted chlorine disappeared in the ultraviolet treatment for a long time, and that a sufficient photochemical reaction proceeded.

Example 3 Investigation of Solvent in Photochemical Treatment As a solvent for dissolving PCB, 70% methanol + 2% NaOH and 70% methanol + 2% KOH were used instead of methanol. 70% methanol + 2%
Canelol 500 was dissolved in NaOH to a concentration of 500 ppm, and the result of UV treatment for 6 hours was dissolved in 70% methanol + 2% KOH to dissolve Canerol 500 to a concentration of 2000 ppm. hand,
The result of UV treatment for 8 hours is shown in FIG. In each case, the peak of the congener with 4-substituted chlorine number disappeared, indicating that a sufficient photochemical reaction is proceeding.

(Example 4-Treatment with TK102) TK102 cells were inoculated into 3 test tubes containing 5 ml of the above decomposition medium containing 20 ppm of KC400 and 3000 ppm of biphenyl, and the above decomposition medium was inoculated at 30 ° C for 7 days. Shake culture was performed. The residual PCB was extracted from the culture with 2 ml of ethyl acetate and 1 ml of it was subjected to gas chromatography. The results are shown in FIGS. 5 and 6.

FIG. 5A shows a gas chromatography chart of a control without the addition of bacterial cells, and FIGS.
A and FIG. 6B show the experimental results of triplicates. In each chart, trichlorine-substituted PCB congener until around 17 minutes,
It can be considered that from about 18 minutes to about 20 minutes, it shows a 4-chlorine substitution congener, from about 20 minutes to about 22 minutes, a 5-chlorine substitution congener, and from about 22 minutes or more, it shows a 6-chlorine substitution congener.

More specifically, the peak of reference numeral 1 is the following chemical formula (I), the peak of reference numeral 2 is the following chemical formula (II), the peak of reference numeral 3 is the following chemical formula (III), and the peak of reference numeral 4 is the following chemical formula (II). IV), the peak of code 5 is the following chemical formula (v),
It is considered that the peak of reference numeral 6 indicates the presence of a congener represented by the following chemical formula (VI) and the peak of reference numeral 7 indicates the presence of a congener represented by the following chemical formula (VII).

[0042]

Embedded image

Comparing the control (FIG. 4A) with the bacterial cell-added sample (FIGS. 5B, 6A, and 6B), it can be seen that some peaks disappear in FIGS. 5B, 6A, and 6B. . For example, among the above-mentioned seven peaks, peak 1 and peak 2 are completely disappeared in FIGS. 5B, 6A, and 6B, and it can be seen that the congeners of the chemical formulas (I) and (II) are decomposed by TK102 alone. . Figure 5
B, FIG. 6A, and FIG. 6B, there are peak 5, peak 6, and peak 7 remaining in the vicinity of 17 minutes. Since these are all 4-base substitution congeners, 3 There is no substitution congener peak, indicating that the trichlorine substitution congener can decompose TK102.

Further, it can be seen that some tetrachlorine-substituted congeners can be decomposed. For example, since peaks 3 and 4 have disappeared, the chemical formulas (III) and (I
It can be seen that the congener represented by V) has been decomposed. However, some tetrachlorinated congeners have T
Some are not decomposed with K102, such as peak 5,
The tetrachlorine-substituted congeners represented by peaks 6 and 7 cannot be decomposed.

Example 4 Combination of Ultraviolet Treatment and Microbial Treatment Kanechlor 500 was dissolved in methanol,
2 ml of a solution having a concentration of 0.2 vol% was prepared, placed in a cell with a screw cap made of quartz glass, and subjected to ultraviolet ray treatment for 26 hours (3 mW / cm ² ). Take out the PCB solution after UV treatment, add biphenyl (concentration 1000ppm) to grow microorganisms, and then add TK
102 was inoculated into 5 ml of the medium, and shake culture was carried out at 30 ° C. for 7 days. Residual PCB with ethyl acetate from the culture
Was extracted and analyzed by GCMS.

The results of gas chromatography are shown in FIG. FIG. 7A shows an untreated PCB, and FIG. 7B shows a result after 26 hours of ultraviolet ray treatment. Fig. 7C, which was obtained by subjecting the ultraviolet-treated sample to microbial treatment, shows that the chlorine number is 1 or 2.
Has disappeared, and a single peak with a chlorine substitution number of 0 (biphenyl) is shown.
It was confirmed that PCB was decomposed by 2.
The peak of biphenyl in FIG. 7C is high.
This is because biphenyl was added when TK102 was inoculated. As a result of further detailed examination, it was confirmed that the concentrations of all the congeners, which are the constituent components of PCB, were 0.5 ppb or less.

As a control for confirming that this PCB decomposition was TK102-dependent, autoclaved TK102 and biphenyl (concentration: 100) were used.
The results of gas chromatography of a sample shaken at 30 ° C. for 7 days with 0 ppm) are shown in FIG. 7D. A peak with a chlorine number of 2 remains, which shows that it depends on TK102. From the above results, UV treatment and T
It was shown that the microbial treatment with K102 was able to completely decompose the PCB.

(Example 5: Combination of UV treatment and microbial treatment) Kanechlor 500 was dissolved in methanol,
2 ml of a solution having a concentration of 0.2 vol% was prepared, placed in a cell with a screw cap made of quartz glass, and subjected to ultraviolet ray treatment for 26 hours (3 mW / cm ² ). Take out the PCB solution after UV treatment, and use biphenyl (concentration 1000p
pm) was added to 5 ml of a medium in which KKS102 was inoculated, and shake culture was performed at 30 ° C. for 7 days. The residual PCB was extracted from the culture broth with ethyl acetate and analyzed by GCMS.

As a result of gas chromatography, a single peak with a chlorine substitution number of 0 was shown, which was treated with ultraviolet rays and KKS10.
It was confirmed that PCB was decomposed by 2.
As a result of further detailed examination, it was confirmed that the concentrations of all the congeners, which are the constituent components of PCB, were 0.5 ppb or less.

Although the PCB has been described above as an example, in short, after the dechlorination reaction of the number of substituted chlorine by photochemical treatment to the number of substitutions that can be decomposed by the microorganism, the microorganism is decomposed by the microorganism capable of decomposing the organic chlorine compound. Therefore, the method for decomposing an organochlorine compound having the above-mentioned constitution can be widely applied to generally indecomposable organochlorine compounds.

[0051]

INDUSTRIAL APPLICABILITY As described above, the method for decomposing a hardly decomposable organochlorine compound according to the present invention is a photochemical treatment in which a dechlorination reaction is performed by irradiating the hardly decomposable organochlorine compound with an energy ray having a wavelength of 250 nm or less. After that, it is a method of performing a microbial treatment for decomposing the remaining organic chlorine compound by a microorganism capable of decomposing at least a part of the organic chlorine compound.

Therefore, the target hardly decomposable organochlorine compound can be completely decomposed without producing harmful substances. In addition, it is a reaction under normal temperature and pressure,
It is also excellent in that it does not require a large amount of energy as in combustion processing.

Pseudomonas alcaligenes TK102, which is a novel microorganism of the present invention, has a high ability to decompose polychlorinated biphenyls. Biphenyl chloride can be decomposed.

[Brief description of drawings]

FIG. 1 is a scheme showing the degradation pathway of biphenyl or PCB by microorganisms.

FIG. 2 is a diagram showing the results of gas chromatographic examination of changes over time in the decomposition of PCB by UV treatment, where A is untreated PCB, B is UV treatment 3 hours, C is UV treatment 5 hours, and D is D. 15 hours after the ultraviolet ray treatment, E indicates 26 hours after the ultraviolet ray treatment.

FIG. 3 shows that each P after being subjected to UV treatment with a different solvent
It is the figure which showed the result of having investigated the decomposition of CB by the gas chromatography, A shows the result of octane, B shows the result of ethanol, and C shows the result of acetone.

FIG. 4 shows that each P after being subjected to UV treatment with a different solvent
It is the figure which showed the result of having investigated the decomposition | disassembly of CB by the gas chromatography, A is 70% methanol + 2% NaO.
H and B show the results of 70% methanol + 2% KOH.

FIG. 5 is a graph showing the results of gas chromatography in which the degree of decomposition of PCB after the treatment of PCB with only microorganisms was examined.
Shows a control without addition of bacterial cells, and B shows the result with bacterial cells added.

FIG. 6 is a diagram showing the result of gas chromatography in which the degree of decomposition of PCB after treating the PCB with only the microorganism was examined.

FIG. 7 is a diagram showing the results of gas chromatography to investigate the residual PCB at each stage according to the method for decomposing a hardly decomposable organochlorine compound according to the present invention, in which A is an untreated PCB and B is an untreated PCB.
26 hours after UV treatment, C is UV treatment after TK10
After microbial treatment with 2, the D shows the result after treatment by mixing with TK102 cells autoclaved as a control.

Continuation of front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technology display area // (C12N 1/20 C12R 1:38) (72) Inventor Masao Fukuda 1769-1 Fukasawa-cho, Nagaoka-shi, Niigata -1-505 (72) Kazuhide Kanehara 1-6-6 Oyama-cho, Nagaoka City, Niigata Prefecture (72) Keiji Yano 1-41-3 Takinogawa, Kita-ku, Tokyo

Claims (7)

[Claims] 1. The wavelength of the persistent chlorine compound is 250
After photochemical treatment for irradiating a dechlorination reaction with energy rays of nm or less, microbial treatment for decomposing the remaining organic chlorine compound by a microorganism capable of decomposing at least a part of the above organic chlorine compound is performed. Decomposition method of organic chlorine compounds. 2. The method for decomposing a hardly decomposable organochlorine compound according to claim 1, wherein in the photochemical treatment, the hardly decomposable organochlorine compound is dissolved in an organic solvent and irradiated with ultraviolet rays. 3. The method for decomposing a hardly decomposable organochlorine compound according to claim 1, wherein the organochlorine compound is polychlorinated biphenyl. 4. The method for decomposing a hardly decomposable organochlorine compound according to claim 1, wherein the microorganism has a property of decomposing at least the organochlorine compound having a chlorine substitution number of 3 or less. . 5. The method for decomposing a hardly decomposable organochlorine compound according to claim 3 or 4, wherein the microorganism is Pseudomonas alcaligenes TK102. 6. The method for decomposing a persistent organochlorine compound according to claim 3 or 4, wherein the microorganism is Pseudomonas species KKS102. 7. Pseudomonas alcaligenes TK102 having a resolution of polychlorinated biphenyls.