Method for treating halogenated organic pollutants in halogenated organic contaminated soil through combination of chemical leaching and electron beam irradiation

Abstract

The invention relates to a method for treating halogenated organic pollutants in halogenated organic contaminated soil through combination of chemical leaching and electron beam irradiation, and belongs to the technical field of soil remediation and treatment. According to the method, leacheate and halogenated organic contaminated soil are mixed, oscillated and leached, so that halogenated organic pollutants in the halogenated organic contaminated soil enter the leacheate, and the leacheate contains an organic solvent and / or a nonionic surfactant; after leaching, centrifugal treatment is conducted, supernate is subjected to electron beam irradiation, free radicals generated in the irradiation process destroy carbon halogen bonds, and therefore dehalogenation and mineralization of halogenated organic pollution are achieved. Electron beam irradiation can be carried out at normal temperature and normal pressure, chemical reagents are not needed, and the risk of reagent residues is avoided. The leacheate can be directly recycled after being irradiated, so that the treatment cost is reduced. Compared with other repairing technologies, the combined technology is short in repairing period and high in adaptability.

Description

Technical Field

[0001] The present invention belongs to the technical field of soil remediation and treatment, and more specifically, relates to a method for jointly treating halogenated organic pollutants in halogenated organic contaminated soil by chemical leaching and electron beam irradiation. Background Art

[0002] Halogenated organic pollutants such as polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), etc. have high toxicity, poor degradability and bioaccumulation, and often enter the soil through channels such as e-waste disassembly and pesticide use, posing a serious threat to the ecological environment and human health. There are many problems with traditional methods for remediating halogenated organic contaminated soil. For example, the microbial degradation method has a long repair period, strong selectivity for pollutants, and is easily affected by environmental factors in practical applications; the maturity of photocatalytic degradation technology is not high, and there are problems with the cost, stability of the catalyst, and control of reaction conditions, etc. Traditional chemical oxidation / reduction requires the addition of a large amount of reagents, often requires specific reaction conditions, is complex in operation and high in cost, and may change the physical and chemical properties of the soil and affect the ecological function of the soil. In view of the above situation, there is an urgent need to explore a new way to efficiently and massively degrade halogenated organic pollutants in soil. Summary of the Invention

[0003] The present invention solves the problems of incomplete degradation of halogenated organic contaminated soil and high risk of secondary pollution in the prior art. The present invention provides a method for rapidly repairing halogenated organic contaminated sites by using a combined technology of chemical leaching - electron beam irradiation under normal temperature and pressure. Chemical leaching uses organic solvents and / or non-ionic surfactants to improve the desorption efficiency of pollutants, and electron beam irradiation makes up for the limitations of the leaching agent for high-concentration or difficult-to-degrade halogenated organic pollutants, and is applicable to the degradation of various halogenated compounds. In the present invention, organic solvents enhance the solubility of halogenated organic pollutants, especially suitable for the solubilization of low-polarity pollutants. Non-ionic surfactants improve the desorption efficiency of pollutants from soil particles by reducing the interfacial tension. The highly reactive free radicals (·OH, e – ) generated by electron beam irradiation can break the carbon-halogen bond to achieve the reductive dehalogenation and mineralization of halogenated organic pollutants in the leaching solution.

[0004] According to the first aspect of the present invention, there is provided a method for jointly treating halogenated organic pollutants in halogenated organic contaminated soil by chemical leaching and electron beam irradiation. The leaching solution is mixed and oscillated with the halogenated organic contaminated soil to allow the halogenated organic pollutants in the halogenated organic contaminated soil to enter the leaching solution, thereby repairing the halogenated organic contaminated soil;

[0005] The eluent contains an organic solvent and / or a non-ionic surfactant; the halogenated organic pollutant is at least one of polychlorinated biphenyls, hexachlorobenzene, pentachlorobenzene, pentachlorophenol, dioxins, polybrominated diphenyl ethers, hexabromocyclododecane, and brominated biphenyls;

[0006] When the eluent contains an organic solvent, the organic solvent is at least one of methanol, toluene, n-hexane, tetrahydrofuran, acetone, dimethyl sulfoxide, acetonitrile, ethanol, n-propanol, and n-butanol;

[0007] After elution, the obtained eluent is centrifuged, and then the supernatant is irradiated with an electron beam. The free radicals generated during the irradiation break the carbon-halogen bond, causing the halogenated organic pollutant to dehalogenate and mineralize.

[0008] Preferably, the eluent further contains an alkaline substance.

[0009] Preferably, the alkaline substance is at least one of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate, potassium bicarbonate, ammonia water, and triethylamine.

[0010] Preferably, when the eluent contains a non-ionic surfactant, the concentration of the non-ionic surfactant is 0.8 g / L - 4.8 g / L;

[0011] When the eluent contains both an organic solvent and a non-ionic surfactant, the concentration of the non-ionic surfactant in the eluent is 0.8 g / L - 4.8 g / L, and the dosage of the organic solvent accounts for less than 5% of the volume of the eluent.

[0012] Preferably, the concentration of the alkaline substance in the eluent is 0.5 - 50 mmol / L.

[0013] Preferably, when the eluent contains a non-ionic surfactant, the non-ionic surfactant is at least one of Triton X–100, Triton X–114, Triton X–405, NP–40, Brij–30, Span–20, Span–40, Span–60, Span–80, Tween–20, Tween–40, Tween–60, and Tween–80.

[0014] Preferably, the ratio of the volume of the eluent to the mass of the halogenated organic contaminated soil is 5 - 20 L / kg.

[0015] Preferably, the time for mixed oscillating elution is 0.5 - 2 h.

[0016] Preferably, the irradiation dose of the electron beam irradiation is 40 kGy or less.

[0017] Preferably, the irradiation dose of the electron beam irradiation is 8 - 16 kGy.

[0018] Generally speaking, compared with the prior art, the above technical solutions conceived by the present invention mainly have the following technical advantages:

[0019] (1) Halogenated pollutants usually have a certain hydrophobicity. Organic solvents can interact with halogenated pollutants and dissolve the halogenated pollutants in the organic phase through the principle of like dissolves like. After the non-ionic surfactant reaches a certain concentration in the solution, micelles will be formed, and the halogenated pollutants can be wrapped in the hydrophobic region inside the micelles, thereby increasing their solubility in the aqueous solution. The organic solvent and / or non-ionic surfactant of the present invention can make the pollutants more easily detached from the soil and enter the leaching solution, facilitating subsequent treatment.

[0020] (2) The present invention uses the chemical leaching method combined with the electron beam irradiation technology for the rapid remediation of halogenated contaminated sites. Preferably, the chemical leaching is compounded by an organic solvent (solubilizing organic phase), an alkali (adjusting pH to enhance dehalogenation), and a non-ionic surfactant (such as Triton X–100). There is a synergistic effect among these three components, which can achieve the rapid dehalogenation and degradation of halogenated organic pollutants and optimize the desorption efficiency of pollutants. The electron beam irradiation makes up for the limitations of the leaching agent for high-concentration or refractory halogenated organic pollutants and is applicable to the degradation of various halogenated compounds. The non-ionic surfactant (such as Triton X–100) improves the desorption efficiency of pollutants from soil particles by reducing the soil-water interfacial tension. The organic solvent is beneficial to the solubility of low-polarity halogenated POPs, and the alkaline condition promotes the dehalogenation reaction of halogenated compounds. The highly reactive free radicals (·OH, e – ) generated by the electron beam irradiation can break the carbon-halogen bond and have unique advantages in treating halogenated pollutants.

[0021] (3) The existing chemical oxidation / reduction methods for directly treating halogenated organic contaminated soil require a large amount of chemicals (such as Fenton reagent, zero-valent iron), and will cause damage to the soil structure. The leaching solution leaching combined with electron beam irradiation of the present invention can operate at normal temperature and pressure without adding chemical reagents and has no risk of chemical reagent residues; moreover, the leaching solution can be directly recycled after irradiation, reducing the treatment cost; compared with other remediation technologies, the combined technology has a short remediation cycle and strong adaptability. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is the effect diagram of treating BDE47 contaminated soil in Example 1, Example 2, Example 3, and Example 4 of the present invention.

[0023] Figure 2 It is the effect diagram of directly irradiating BDE47 contaminated soil by electron beam in Comparative Example 1 of the present invention.

[0024] Figure 3 These are the effect diagrams of treating BDE47-contaminated soil in Example 5, Example 6, and Example 7 of the present invention.

[0025] Figure 4 These are the effect diagrams of electron beam irradiation after leaching BDE47-contaminated soil with methanol and Na2CO3 as leaching agents in the present invention.

[0026] Figure 5 These are the effect diagrams of treating BDE15- and BDE209-contaminated soil in Example 5 and Example 6 of the present invention respectively.

[0027] Figure 6 These are the effect diagrams of leaching and debromination of BDE47-contaminated soil by using methanol as a leaching agent in combination with electron beam irradiation for five cycles in the present invention. Detailed implementation manners

[0028] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0029] Comparative Example 1: Direct electron beam irradiation of BDE47-contaminated soil

[0030] Accurately weigh 1 g of BDE47-contaminated soil (contamination concentration is 100 mg / kg), place it in a sealed bag, and under the action of electron beam irradiation, perform irradiation treatments at doses of 50, 100, 200, 500, 800, and 1000 kGy respectively. Subsequently, accurately weigh 10 mg of the soil powder after irradiation with a specific dose, dissolve it in 5 mL of methanol, and transfer it to a volumetric flask and make up to 10 mL with methanol. Then take 1 mL of the solution, dilute it to 10 mL with methanol, and measure the degradation rate of BDE47 according to the analysis method in Example 1.

[0031] Example 1: Using Triton X-100, Na2CO3, and methanol as leaching agents in combination with electron beam irradiation to treat BDE47-contaminated soil

[0032] Weigh 1 g of 2,2 ’ ,4,4 ’The soil contaminated with brominated diphenyl ether (BDE47) (100 mg / kg) was placed in a 30 mL centrifuge tube, and 10 mL of eluent was added. The concentration of Triton X-100 was 4.8 g / L, the concentration of Na2CO3 was 0.5 mmol / L, and the volume of methanol was 0.5%. Using the batch equilibrium oscillation method, the centrifuge tube was placed in a water bath oscillator at a temperature of 25 °C and a rotation speed of 200 rpm. After 2 h of oscillation, the sample was transferred to a centrifuge at 3500 rpm and centrifuged for 30 min. Subsequently, 1 mL of the supernatant was taken and placed in a glass bottle, and irradiated with doses of 8, 16, 24, 32, and 40 kGy, respectively. After filtration, the degradation rate and debromination rate of the irradiated solution were measured by liquid chromatography and ion chromatography, respectively.

[0033] Example 2: Treatment of BDE47-contaminated soil by combining Triton X-100 and Na2CO3 as eluents with electron beam irradiation

[0034] Weigh 1 g of 2,2 ’ ,4,4 ’ The soil contaminated with brominated diphenyl ether (BDE47) (100 mg / kg) was placed in a 30 mL centrifuge tube, and 10 mL of eluent was added. The concentration of Triton X-100 was 4.8 g / L, the concentration of Na2CO3 was 0.5 mmol / L. Using the batch equilibrium oscillation method, the centrifuge tube was placed in a water bath oscillator at a temperature of 25 °C and a rotation speed of 200 rpm. After 2 h of oscillation, the sample was transferred to a centrifuge at 3500 rpm and centrifuged for 30 min. Subsequently, 1 mL of the supernatant was taken and placed in a glass bottle, and irradiated with doses of 8, 16, 24, 32, and 40 kGy, respectively. After filtration, the degradation rate and debromination rate of the irradiated solution were measured by liquid chromatography and ion chromatography, respectively.

[0035] Example 3: Treatment of BDE47-contaminated soil by combining Triton X-100 and methanol as eluents with electron beam irradiation

[0036] Weigh 1 g of 2,2 ’ ,4,4 ’ The soil contaminated with brominated diphenyl ether (BDE47) (100 mg / kg) was placed in a 30 mL centrifuge tube, and 10 mL of eluent was added. The concentration of Triton X-100 was 4.8 g / L, and the volume of methanol was 0.5%. Using the batch equilibrium oscillation method, the centrifuge tube was placed in a water bath oscillator at a temperature of 25 °C and a rotation speed of 200 rpm. After 2 h of oscillation, the sample was transferred to a centrifuge at 3500 rpm and centrifuged for 30 min. Subsequently, 1 mL of the supernatant was taken and placed in a glass bottle, and irradiated with doses of 8, 16, 24, 32, and 40 kGy, respectively. After filtration, the degradation rate and debromination rate of the irradiated solution were measured by liquid chromatography and ion chromatography, respectively.

[0037] Example 4: Triton X-100 as an eluent combined with electron beam irradiation for treating BDE47-contaminated soil

[0038] Weigh 1 g of soil contaminated with 2,2 ’ ,4,4 ’ bromodiphenyl ether (BDE47) (100 mg / kg) into a 30 mL centrifuge tube, add 10 mL of eluent, where the concentration of Triton X–100 is 4.8 g / L. Using the batch equilibrium oscillation method, place the centrifuge tube in a water bath oscillator at a temperature of 25 °C and a rotation speed of 200 rpm. After 2 h of oscillation, transfer the sample to a centrifuge at 3500 rpm and centrifuge for 30 min. Then, take 1 mL of the supernatant and place it in a glass bottle, and perform irradiation treatments at doses of 8, 16, 24, 32, and 40 kGy respectively. After filtration, the degradation rate and debromination rate of the irradiated solution are measured by liquid chromatography and ion chromatography respectively.

[0039] Example 5: Effect of electron beam irradiation on methanol-eluted BDE47-contaminated soil

[0040] Weigh 1 g of soil contaminated with 2,2 ’ ,4,4 ’ bromodiphenyl ether (BDE47) (100 mg / kg) into a 10 mL centrifuge tube, add a total of 10 mL of methanol, and perform ultrasonic-assisted elution three times (4, 4, 2 mL), with each elution time being 20 min. After transferring the sample to a centrifuge at 8000 rpm and centrifuging for 30 min, combine the eluents and make up the volume to 10 mL with methanol. Then, take 1 mL of the solution and place it in a glass bottle, and perform irradiation treatments at doses of 4, 8, 12, 16, and 20 kGy respectively, and measure the degradation rate and debromination rate of BDE47 according to the analysis method in Example 1.

[0041] Example 6: Effect of electron beam irradiation on ethanol-eluted BDE47-contaminated soil

[0042] Weigh 1 g of soil contaminated with 2,2 ’ ,4,4 ’ bromodiphenyl ether (BDE47) (100 mg / kg) into a 10 mL centrifuge tube, add a total of 10 mL of ethanol, and perform ultrasonic-assisted elution three times (4, 4, 2 mL), with each elution time being 20 min. After transferring the sample to a centrifuge at 8000 rpm and centrifuging for 30 min, combine the eluents and make up the volume to 10 mL with methanol. Then, take 1 mL of the solution and place it in a sealed bag, and perform irradiation treatments at doses of 4, 8, 12, 16, and 20 kGy respectively, and measure the degradation rate and debromination rate of BDE47 according to the analysis method in Example 1.

[0043] Example 7: Effect of n-propanol on the electron beam irradiation after leaching of BDE47-contaminated soil

[0044] Weigh 1 g of soil contaminated with 2,2 ’ ,4,4 ’ bromodiphenyl ether (BDE47) (100 mg / kg) into a 10 mL centrifuge tube, add a total of 10 mL of n-propanol, and leach it three times under ultrasonic assistance (4, 4, 2 mL), with a leaching time of 20 min each time. After transferring the sample to a centrifuge at 8000 rpm and centrifuging for 30 min, combine the leachates, and make up the volume to 10 mL with methanol. Then take 1 mL of the solution and place it in a sealed bag, and perform irradiation treatments with doses of 4, 8, 12, 16, and 20 kGy respectively, and measure the degradation rate and debromination rate of BDE47 according to the analysis method in Example 1.

[0045] Example 8: Effect of methanol and Na2CO3 on the electron beam irradiation after leaching of BDE47-contaminated soil

[0046] Weigh 1 g of soil contaminated with 2,2 ’ ,4,4 ’ bromodiphenyl ether (BDE47) (100 mg / kg) into a 10 mL centrifuge tube, add a total of 10 mL of methanol solution (containing 0.5 mM Na2CO3), and leach it three times under ultrasonic assistance (4, 4, 2 mL), with a leaching time of 20 min each time. After transferring the sample to a centrifuge at 8000 rpm and centrifuging for 30 min, combine the leachates, and make up the volume to 10 mL with methanol. Then take 1 mL of the solution and place it in a sealed bag, and perform irradiation treatments with doses of 4, 8, 12, 16, and 20 kGy respectively, and measure the degradation rate and debromination rate of BDE47 according to the analysis method in Example 1.

[0047] Example 9: Extraction and degradation of BDE47-contaminated soil by using methanol as a leaching agent in combination with electron beam irradiation after five cycles

[0048] Weigh 1 g of soil contaminated with 2,2 ’ ,4,4 ’ bromodiphenyl ether (BDE47) (100 mg / kg) into a 10 mL centrifuge tube, add a total of 10 mL of methanol, and leach it three times under ultrasonic assistance (4, 4, 2 mL), with a leaching time of 20 min each time. Then transfer the sample to a centrifuge at 8000 rpm and centrifuge for 30 min, combine the leachates, and make up the volume to 10 mL with methanol. Then place 10 mL of the solution in a sealed bag and irradiate it with 12 kGy under an electron beam. The irradiated leachate is carried out according to the above steps, and the degradation rate of BDE47 is measured according to the analysis method in Example 1.

[0049] Example 10: Influence of Methanol on Electron Beam Irradiation after Leaching of BDE15-Contaminated Soil

[0050] Weigh 1 g of soil contaminated with 4,4'-dibromodiphenyl ether (BDE15) (100 mg / kg) into a 10 mL centrifuge tube, add a total of 10 mL of methanol, and perform leaching three times (4, 4, 2 mL) under ultrasonic assistance, with each leaching time being 20 min. After transferring the sample to a centrifuge at 8000 rpm and centrifuging for 30 min, combine the leachates and make up to 10 mL with methanol. Subsequently, take 1 mL of the solution and place it in a sealed bag, and perform irradiation treatments at doses of 4, 8, 12, 20, and 30 kGy respectively, and measure the degradation rate and debromination rate of BDE47 according to the analysis method in Example 1.

[0051] Example 11: Influence of Methanol on Electron Beam Irradiation after Leaching of BDE209-Contaminated Soil

[0052] Weigh 1 g of soil contaminated with decabromodiphenyl ether (BDE209) (100 mg / kg) into a 10 mL centrifuge tube, add a total of 10 mL of methanol (containing 50% by volume of THF), and perform leaching three times (4, 4, 2 mL) under ultrasonic assistance, with each leaching time being 20 min. After transferring the sample to a centrifuge at 8000 rpm and centrifuging for 30 min, combine the leachates and make up to 10 mL with methanol. Subsequently, take 1 mL of the solution and place it in a sealed bag, and perform irradiation treatments at doses of 4, 8, 12, 20, and 30 kGy respectively, and measure the degradation rate and debromination rate of BDE47 according to the analysis method in Example 1.

[0053] Results and Analysis

[0054] Test the effect of using Triton X–100, Na2CO3, and methanol as leaching agents in Example 1 and combining with electron beam irradiation to treat BDE47-contaminated soil. As Figure 1 shown, when the irradiation dose is only 8 kGy, BDE–47 in the mixed leachate can achieve complete debromination and degradation. In Example 2, when using Triton–100 and 0.5 mM Na2CO3 as leaching agents and then performing irradiation, when the irradiation dose is 16 kGy, the debromination rate of BDE–47 in the leachate is 80%. In Example 3, when using Triton–100 and methanol as leaching agents and then performing irradiation, when the irradiation dose reaches 40 kGy, its degradation rate can reach 80% and the debromination rate reaches 70%. In Example 4, when using Triton X–100 alone as the leaching agent and then performing irradiation, when the irradiation dose reaches 40 kGy, its degradation rate can reach 80%. In comparison, the mixed leaching agent composed of Triton X–100, Na2CO3, and methanol has the best effect in the process of electron beam irradiation for degrading BDE–47.

[0055] Test the degradation effect of direct electron beam irradiation on BDE47-contaminated soil. As Figure 2 shown, when the electron beam irradiation is directly applied to BDE47-contaminated soil, the remediation effect is not ideal and the degradation rate is relatively slow. Even when the irradiation dose is as high as 1000 kGy, the degradation rate of BDE47 is only 80%, and the debromination rate is 50%.

[0056] Test the degradation effect of direct electron beam irradiation on BDE47 with methanol as the eluent in Test Example 5. The results are as Figure 3 shown. After extracting BDE47 from the soil by chemical leaching with methanol as the eluent and then performing electron beam irradiation degradation, it shows significant high efficiency. At an irradiation dose of 12 kGy, BDE47 can achieve complete debromination degradation.

[0057] Test the degradation effect of direct electron beam irradiation on BDE47 with ethanol as the eluent in Test Example 6. The results are as Figure 3 shown. After extracting BDE47 from the soil by chemical leaching with ethanol as the eluent and then performing electron beam irradiation degradation, it also shows significant high efficiency. At an irradiation dose of 20 kGy, the debromination rate of BDE47 reaches 80%.

[0058] Test the degradation effect of direct electron beam irradiation on BDE47 with n-propanol as the eluent in Test Example 7. The results are as Figure 3 shown. After extracting BDE47 from the soil by chemical leaching with n-propanol as the eluent and then performing electron beam irradiation degradation, it shows good high efficiency. At an irradiation dose of 12 kGy, BDE47 can achieve complete degradation, and at an irradiation dose of 20 kGy, the debromination rate reaches 60%.

[0059] Test the degradation effect of direct electron beam irradiation on BDE47 with methanol and Na2CO3 as the eluent in Test Example 8. The results are as Figure 4 shown. After extracting BDE47 from the soil by chemical leaching with methanol and Na2CO3 as the eluent and then performing electron beam irradiation degradation, after adding a certain concentration of Na2CO3, the irradiation degradation is not inhibited. At an irradiation dose of 12 kGy, BDE47 can achieve complete debromination degradation.

[0060] Test the degradation effect of direct electron beam irradiation on BDE15 with methanol as the eluent in Test Example 9. The results are as Figure 5 shown. After extracting BDE15 from the soil by chemical leaching with methanol as the eluent and then performing electron beam irradiation degradation, it shows good high efficiency. At an irradiation dose of 12 kGy, BDE15 can achieve complete debromination degradation.

[0061] Test Example 10: The degradation effect of BDE209 by direct electron beam irradiation with methanol (containing 50% by volume of THF) as the eluent. The results are as Figure 5 shown. After extracting BDE209 from the soil by chemical elution with methanol (containing 50% by volume of THF) as the eluent and then performing electron beam irradiation degradation, it shows good high efficiency. At an irradiation dose of 30 kGy, BDE209 can achieve complete debromination degradation.

[0062] Test Example 11: The effect of combined chemical elution - electron beam irradiation cyclic treatment on BDE47 - contaminated soil. The results are as Figure 6 shown. Methanol as the eluent for BDE47 - contaminated soil has an extraction efficiency of 99%. The methanol eluent after extraction can achieve complete debromination removal of BDE47 through electron beam irradiation, and the recovered methanol can be reused for the extraction of contaminated soil. After five cycles of elution / irradiation treatment, the elution rate of BDE47 remains above 98%, and the debromination rate still reaches 100%.

[0063] Those skilled in the art can easily understand that the above - mentioned are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for treating halogenated organic pollutants in halogenated organic contaminated soil by combining chemical leaching and electron beam irradiation, characterized in that, The leaching solution is mixed and oscillated with the halogenated organic contaminated soil, so that the halogenated organic pollutants in the halogenated organic contaminated soil enter the leaching solution, thereby repairing the halogenated organic contaminated soil; The leaching solution contains an organic solvent and / or a non-ionic surfactant; the halogenated organic pollutants are at least one of polychlorinated biphenyls, hexachlorobenzene, pentachlorobenzene, pentachlorophenol, dioxins, polybrominated diphenyl ethers, hexabromocyclododecane, and brominated biphenyls; When the leaching solution contains an organic solvent, the organic solvent is at least one of methanol, toluene, n-hexane, tetrahydrofuran, acetone, dimethyl sulfoxide, acetonitrile, ethanol, n-propanol, and n-butanol; After leaching, the obtained leaching solution is centrifuged, and then the supernatant is irradiated with electron beams. The free radicals generated during the irradiation destroy the carbon-halogen bond, causing the halogenated organic pollutants to dehalogenate and mineralize.

2. The method for treating halogenated organic pollutants in halogenated organic contaminated soil by combined use of chemical leaching and electron beam irradiation as claimed in claim 1, characterized in that The leaching solution also contains an alkaline substance.

3. The method for treating halogenated organic pollutants in halogenated organic contaminated soil by combining chemical leaching and electron beam irradiation as claimed in claim 2, wherein The alkaline substance is at least one of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate, potassium bicarbonate, ammonia water, and triethylamine.

4. The method for treating halogenated organic pollutants in halogenated organic contaminated soil by combining chemical leaching and electron beam irradiation as claimed in claim 1, wherein, When the leaching solution contains a non-ionic surfactant, the concentration of the non-ionic surfactant is 0.8 g / L - 4.8 g / L; When the leaching solution contains both an organic solvent and a non-ionic surfactant, the concentration of the non-ionic surfactant in the leaching solution is 0.8 g / L - 4.8 g / L, and the dosage of the organic solvent accounts for less than 5% of the volume of the leaching solution.

5. The method for treating halogenated organic pollutants in halogenated organic contaminated soil by combining chemical leaching and electron beam irradiation as claimed in claim 2 or 3, characterized in that, The concentration of the alkaline substance in the leaching solution is 0.5 - 50 mmol / L.

6. The method for treating halogenated organic pollutants in halogenated organic contaminated soil by combining chemical leaching and electron beam irradiation as claimed in claim 1, wherein, When the leaching solution contains a non-ionic surfactant, the non-ionic surfactant is at least one of Triton X–100, Triton X–114, Triton X–405, NP–40, Brij–30, Span–20, Span–40, Span–60, Span–80, Tween–20, Tween–40, Tween–60, and Tween–80.

7. The method for treating halogenated organic pollutants in halogenated organic contaminated soil by combining chemical leaching and electron beam irradiation as claimed in claim 1, wherein The ratio of the volume of the leaching solution to the mass of the halogenated organic contaminated soil is 5 - 20 L / kg.

8. The method for treating halogenated organic pollutants in halogenated organic contaminated soil by combining chemical leaching and electron beam irradiation as claimed in claim 1, characterized in that, The time for the mixed oscillating leaching is 0.5 - 2 h.

9. The method for treating halogenated organic pollutants in halogenated organic contaminated soil by combining chemical leaching and electron beam irradiation as claimed in claim 1, wherein The irradiation dose of the electron beam irradiation is below 40 kGy.

10. The method for treating halogenated organic pollutants in halogenated organic contaminated soil by combining chemical leaching and electron beam irradiation as claimed in claim 8, characterized in that, The irradiation dose of the electron beam irradiation is 8 - 16 kGy.

Images