KR100811105B1 - Composition of Soil Remediation - Google Patents

Abstract

The present invention relates to a composition for restoring contaminated soil, and more particularly, to a composition for restoring contaminated soil comprising a certain amount of a nonionic surfactant in hydrogen peroxide, and contaminated with an oil or a hydrophobic solvent by oxidation of hydrogen peroxide in the composition. It is possible to decompose soil contaminants and reduce the consumption of hydrogen peroxide through the use of nonionic surfactants, so that radicals generated by hydrogen peroxide oxidation can penetrate deeply into contaminated soils. The present invention relates to an improved contaminated soil restorative composition for purifying and restoring soil contaminated with a hydrophobic solvent at low cost.

Oil, contaminated soil, hydrogen peroxide, nonionic surfactant, restoration

Description

Composition for Soil Remediation {Composition of Soil Remediation}

The present invention relates to a composition for restoring contaminated soil, and more particularly, to a composition for restoring contaminated soil comprising a certain amount of a nonionic surfactant in hydrogen peroxide, and contaminated with an oil or a hydrophobic solvent by oxidation of hydrogen peroxide in the composition. It is possible to decompose soil contaminants and reduce the consumption of hydrogen peroxide through the use of nonionic surfactants, so that radicals generated by hydrogen peroxide oxidation can penetrate deeply into contaminated soils. The present invention relates to an improved contaminated soil restorative composition for purifying and restoring soil contaminated with a hydrophobic solvent at low cost.

In the past, organic substances harmful to the environment, such as petroleum, such as diesel, and petroleum products such as oil, have been used. These toxic substances are separated from the original environment and used and disposed of, but in reality, they are produced by the place of manufacture, storage, and place of use. Substantial amounts of leakage or release around them have spread and mix in the atmosphere and in the soil.

The highly toxic organics are difficult to dispose of after use, and may be dumped in large quantities in acid, etc. The organics are difficult to decompose depending on the microorganisms in the soil. Is spreading, which is a major factor in environmental destruction.

As a method for purifying soil contaminated with such hardly decomposable organic substances, the following method has been proposed.

In other words, the method of spreading and incineration of contaminated soil, sealing the surface of the soil with rubber sheets, cement, concrete, etc. to prevent contaminants from spreading by rainwater, sealing the heated soil, infusing steam, or decompressing To separate volatile contaminants from the soil, insert a pipe into the soil layer, connect a vacuum exhaust pump to the pipe to recover the contaminants as steam, and pump and purify the contaminated groundwater again. There is a method of repeatedly purifying the basement, a method of inserting an electrode into a contaminated part, passing a current therein to decompose or fix the contaminant by Joule heat, or a method of contacting the contaminant with hydrogen peroxide.

However, the above-described method is effective in its own way when the contamination range is narrow. However, when the contamination range is widened, the treatment cost and duration are too large, and thus, there is no practical value.

On the other hand, as a method of restoring contaminated soil by chemical oxidation treatment, the method of contacting contaminated soil with hydrogen peroxide (Fenton reaction) is a method of decomposing contaminants by contacting iron salt with hydrogen peroxide to generate OH- radicals to decompose contaminants. It's a very effective way.

However, the above method has a problem in that the consumption of hydrogen peroxide is high and the channeling phenomenon occurs depending on the type of soil, resulting in many economic losses.

Accordingly, the present inventors have completed the present invention by developing a composition comprising hydrogen peroxide and a certain amount of nonionic surfactant as a result of research efforts to solve the above problems.

According to the present invention, it is possible to decompose an oil or a hydrophobic solvent which is a pollutant of soil contaminated with an oil or a hydrophobic solvent by the oxidation of hydrogen peroxide, and a radical generated from hydrogen peroxide while reducing the consumption of the hydrogen peroxide by using a nonionic surfactant. This can penetrate deep into contaminated soil.

Accordingly, an object of the present invention is to provide an improved contaminated soil restorative composition which enables to clean and restore soil contaminated with oil or hydrophobic solvent at low cost.

The present invention is characterized by a composition for restoring contaminated soil containing 0.05 to 5% by weight of a nonionic surfactant in an aqueous hydrogen peroxide solution at a concentration of 1.0 to 35.0% by weight.

Hereinafter, the present invention will be described in detail.

The present invention provides a composition for restoring a contaminated soil containing a certain amount of a nonionic surfactant in hydrogen peroxide, the petroleum hydrocarbon (total petroleum Hydrocarbon, which is a contaminant of soil contaminated with oil or hydrophobic solvent by the oxidation of hydrogen peroxide in the composition) TPH) and other hydrophobic solvents can be decomposed and radicals generated by hydrogen peroxide oxidation can penetrate deeply into contaminated soils while reducing the consumption of hydrogen peroxide through the use of nonionic surfactants. The present invention relates to an improved contaminated soil restorative composition which enables low cost purification and restoration of soil contaminated with oil or hydrophobic solvents.

That is, the present invention provides a composition for restoring contaminated soil in which a non-ionic surfactant is contained in a predetermined range in an aqueous hydrogen peroxide solution as a composition capable of restoring soil contaminated with hardly decomposable organic substances. The soil can be repaired by injecting it into soil contaminated with hardly degradable organics.

The composition for restoring contaminated soil of the present invention comprises a certain amount of a nonionic surfactant in an aqueous hydrogen peroxide solution.

The nonionic surfactant may be a polyoxyalkylene copolymer represented by the following formula (1).

[Formula 1]

RO- (CH ₂ CH ₂ O) nH

In Chemical Formula 1, R is an alkyl group or phenyl group having 8 to 9 carbon atoms, and n is an integer ranging from 5 to 16.

Such nonionic surfactants are preferably biodegradable polyoxyalkylene copolymers, and more preferably polyoxyethylene lauryl ether, polyoxyethylene nonylphenyl ether and polyoxyethylene octylphenyl ether.

Such a nonionic surfactant contains 0.05 to 5.0% by weight in an aqueous hydrogen peroxide solution, preferably in the range of 0.1 to 3% by weight. At this time, when the hydrogen peroxide containing less than 0.05% by weight of the nonionic surfactant is injected into the contaminated soil, the diffusion or emulsifying power of organic matters is not effective, and the hydrogen peroxide contained in excess of 5.0% by weight is injected into the contaminated soil. In this case, not only the economic benefits are lowered, but the surfactant itself may act as a soil pollutant.

Nonionic surfactants act to emulsify hardly degradable organics, reduce the amount of aqueous hydrogen peroxide solution, and deliver OH radicals generated by the oxidation of hydrogen peroxide deep into the soil, allowing for the restoration of contaminated soil over a wide range. .

The aqueous hydrogen peroxide solution is preferably used in an aqueous solution having a concentration of 1.0 to 15% by weight, preferably in the range of 5.0 to 10.0% by weight.

The soil naturally contains various types of metals or metal salts, and hydrogen peroxide reacts with the metals or metal salts naturally included in the soil to restore contaminated soil by oxidizing power to generate OH radicals.

If necessary, a metal catalyst may be added to restore the contaminated soil in an area where the content of metal or metal salt in the soil is too low. That is, as the metal catalyst, any metal compound capable of reacting with hydrogen peroxide to generate OH radicals can be used. Particularly, economical aspects include metal iron or iron compounds. However, it is preferable to use granular or powdered metal catalysts.

As the catalyst, preferred are iron oxides such as metal iron, ferrous oxide, ferric oxide and magnetite, ferrous hydroxide, ferric hydroxide, iron sulfate (I) and (II), and iron chloride (I). ), And (II), various iron compounds may be used, and a roll scale generated in the process of draining the rolling process of the steel mill or iron hydroxide sludge generated in the pickling process of the plating cold rolling process may also be used.

The metal iron or iron compound as such a catalyst can be used in the range of 30 to 100 g in 100 L of an aqueous hydrogen peroxide solution in terms of iron atoms.
Fenton oxidation reaction,
^{_{Fe 2+ + H 2 O 2 →}} Fe 3+ + OH - + OH ·
RH + OH → H ₂ O + R
R + Fe ³⁺ → Fe ²⁺ + product
It is made of the condition that, due to the characteristics of the Korean soil contains a lot of iron, it is common to use without the addition of a catalyst. At this time, it is preferable to use the ratio of the catalyst and hydrogen peroxide in the range of 30 to 100 g in 100 L of the hydrogen peroxide aqueous solution as described above. In the present invention, the hydrogen peroxide aqueous solution is maintained at an appropriate concentration to maintain the pH, an important factor of the Fenton oxidation reaction in an appropriate range.

In the presence of the catalyst, the nonionic surfactant first decomposes the hardly decomposable organic material, and the decomposed organic material reacts with hydrogen peroxide and iron ions to generate OH radicals, thereby expressing a strong oxidizing power.

In addition, since the iron ions and the nonionic surfactant play a role of transporting the OH radicals deep into the soil, it is possible to oxidatively decompose the hardly decomposable organic substances present in the soil.

In other words, only oxidation of hydrogen peroxide promoted by iron ions requires the least stoichiometric hydrogen peroxide or iron catalyst required for the oxidative decomposition of hardly decomposable organic substances in contaminated soil. According to the present invention, a nonionic surfactant is used. Since it is used simultaneously, since the usage-amount of hydrogen peroxide and a catalyst can be drastically reduced, it is more preferable.

In addition, in the case of using the metal iron or iron compound as the catalyst, partial reaction such as partial dechlorination, low molecular weight, ring opening of the benzene ring, addition of OH group or COOH group, etc. in the contaminated soil may proceed. In addition, the degradability of the hardly decomposable organic substance by the use of a nonionic surfactant is remarkably improved, and the object of the present invention can be achieved only by chemical oxidation treatment by using the composition for restoring contaminated soil of the present invention.

However, after applying the composition for restoring contaminated soil of the present invention, if an appropriate microorganism treatment used for restoring contaminated soil is added, the hardly decomposable organic substance can be more completely decomposed.

The contaminated soil restorative composition of the present invention is soil contaminated with oils such as total petroleum hydrocarbon (TPH) or various hydrophobic solvents, soil contaminated with synthetic organic matter which is not decomposed in a short time by microorganisms in the soil, and the like. It may be applied, for example, on the site of a factory, industrial waste treatment plant, a place where industrial waste is disposed of, and the surroundings thereof. These places vary from place to place, but include, for example, petroleum such as crude oil, heavy oil, light oil, kerosene and lubricating oil, perchloroethylene, trichloroethylene, tetrachloroethane, trichloroethane, chlorobenzenes, chloronaphthalenes and poly Organic chlorine compounds such as chloro biphenyls (PCBs), aromatics such as phenol, toluene, catechol, biphenyl, chinoline, dibenzofuran, pyrene, phenanthrene, anthracene, fluorene and acenaphthene The present invention relates to a composition for restoring soil contaminated by soil, which is contaminated with a compound, microchlorodegradable organic substances such as pesticides or preservatives such as dichloro diphenyl trichloroethane (DDT), benzene hexachloride (BHC), cresol, thiuram and SIMADEX. Applicable

Referring to the method for restoring contaminated soil using the composition for restoring contaminated soil of the present invention in detail.

That is, 1) injecting a catalyst for promoting the generation of OH radicals and 2) injecting the composition for restoration of contamination of the present invention into the soil in which the catalyst is injected, wherein the amount of the composition for restoration of contaminated soil restoration The silver may vary depending on the type of pollutant and the degree of contamination. Generally, the amount may be applied in units of 5 to 20 parts by weight based on 100 parts by weight of contaminated soil, and when the injection amount is less than the above range, sufficient organic decomposition effects cannot be expected. If the injection amount is excessively larger than the above range, the remaining contaminated soil restorative composition, in particular, a nonionic surfactant may act as a contaminant.

On the other hand, iron may already be contained in the general soil, and when the iron concentration in the soil is 0.01% by weight or more in terms of iron atoms, it is not necessary to inject the catalyst.

As a method of injecting only the metal iron or iron salt as the catalyst into the contaminated soil separately, for example, 1) adding in a granular or powder form, 2) preparing by spraying with an aqueous solution, 3) preparing by spraying an aqueous solution and in the soil 4) the method of press-fitting through a pipe, 4) spreading the soil and mixing iron in the soil using a kneader. In addition to the above-described method, as long as the catalyst and the soil can be mixed, the purpose as a catalyst can be sufficiently achieved even if it is mixed somewhat unevenly or if rain water is mixed and diffused.

When the metal iron or iron salt as a catalyst is used together with the composition for restoring contaminated soil of the present invention, the metal iron or metal salt as a catalyst may be first injected into the contaminated soil and then the contaminated soil restorative composition of the present invention may be injected. have.

 Even after injecting a catalyst, the composition for restoring contaminated soil of the present invention may be injected by various methods such as 1) spraying the composition on contaminated soil, 2) injecting the composition into a soil through a pipe, and the like. In addition, there is a method of injecting a predetermined amount at a time and a method of injecting a predetermined amount by dividing a few times.

If the degree of contamination by organic matter is high, the method of spraying uniformly and mixing in a mixer generally yields good results.

In order to inject hydrogen peroxide into the soil, it is preferable to use the concentration in the range of 1.0 to 15% by weight, preferably 5.0 to 10.0% by weight of an aqueous hydrogen peroxide solution containing a nonionic surfactant, in order to reduce the unnecessary decomposition of hydrogen peroxide.

After injecting the contaminated soil restorative composition of the present invention into contaminated soil, microorganisms that decompose some of the hardly decomposable organic matter may be injected into the soil if necessary after about 24 hours to 7 days.

When using the composition for restoring contaminated soil of the present invention, the following advantages can be obtained.

That is, since it is possible to purify in situ without carrying out the contaminated soil, it is not necessary to carry out and dispose of a large amount of contaminated soil, and the construction cost is low, and the problem related to the transportation of contaminants can be avoided. In addition, if the decomposition by the microorganism is performed after using the composition for restoring contaminated soil of the present invention, since the hardly decomposable organic matter is decomposed into carbon dioxide and water, safety is extremely large without the occurrence of secondary pollution. In addition, due to the chemical oxidative decomposition by hydrogen peroxide and the degradation synergistic effect of the use of nonionic surfactants, the amount of hydrogen peroxide is much smaller than the theoretical theoretical amount required for the decomposition of hardly decomposable organic materials, and thus the economic benefit is high.

Hereinafter, the present invention will be described in detail with reference to Examples, but the scope of the present invention is not limited by the following Examples.

Example 1

This example was performed to examine the properties of the composition for restoring contaminated soil according to the amount of surfactant used.

Ferric sulfate and polyethylene octylphenyl ether as a nonionic surfactant were mixed in a 10% by weight aqueous hydrogen peroxide solution at a ratio shown in Table 1 below to prepare a contaminated soil restoration composition.

Then, after contaminating by spraying 100 ml of light oil evenly in 1 m 2 of soil containing sandy soil and clay in a 1: 1 weight ratio, 100 ml of the contaminated soil restoring composition prepared above were added and after 1 hour, The results are shown in Table 1 below.

The hydrogen peroxide used is a product of Hansol Chemical Co., Ltd., and the nonionic surfactant is alkyl having R of 8 carbon atoms in RO- (CH ₂ CH ₂ O) nH of [Formula 1] and n of 10. Chem's KINION OP-10 was used.

The area spread in the soil for the contaminated soil restoration composition was measured by the average diameter wetted, the depth of penetration was calculated by measuring the wet average depth, the surface tension was measured using Fisher's MODEL-21, the residual amount of surfactant The measurement was performed using the SHIMADZU 2010 gas chromatography apparatus of the Institute of Agricultural Life Science, affiliated with Gyeongsang National University.

Composition ratio of composition for restoration of contaminated soil Soil spread area (㎠) Soil penetration depth (cm) Surface tension of fruit tree (dyne / cm) Residual amount of surfactant (ppm) Hydrogen peroxide solution (g) Surfactant (g) Iron sulfate (g) Sample 1 97.95 0.05 2 1104.1 4.1 28.3 0 Sample 2 97.8 0.2 2 1134.1 4.5 27.0 0 Sample 3 97 1.0 2 1075.21 4.1 26.8 0 Sample 4 93 5.0 2 1075.21 4.0 26.0 0 Sample 5 91 7.0 2 1076.30 4.1 26.0 50 Sample 6 98 0 2 490.87 3.5 70.9 0

As a result of analysis based on the results shown in Table 1, it is determined based on the characteristics represented by the area, penetration depth, surface tension, etc. spreading the soil in the composition for contaminated soil and the residual amount of the surfactant, the optimum amount of use of the surfactant It can be seen that more effective in the range of 0.05 to 5% by weight.

Example 2

This embodiment was performed to compare the characteristics of each of the components constituting the composition for contaminated soil restoration represented by the area, penetration depth and surface tension and the like spreading the contaminated soil restoration composition in the soil.

The characteristics of the contaminated soil restoration compositions, which were the test subjects, were measured according to the method described in Example 1, and the components constituting each composition and their characteristics are shown in Table 2 below.

The anionic surfactants used were SODIUM DODECYL SULFATE, sulfated oleo-chemically derived linear alcohol, and are manufactured by KYUNG GI OIL CHEM CO., LTD.The cationic surfactants used were alkylamides. Derivative (Alkylamide Derivative) SOFNOL-CKY, a product of Southeast Synthetic Industries.

Furtherance Soil spread area (㎠) Soil penetration depth (cm) Surface tension of fruit tree (dyne / cm) Residual amount of surfactant (ppm) Sample 7 Hydrogen peroxide aqueous solution alone 1017.3 2.2 72 0 Sample 8 Nonionic surfactant alone 1074.2 4.1 25 700 Sample 9 Anionic Surfactant Only 1087.3 4.3 24 700 Sample 10 Cationic Surfactant Only 1065.1 3.5 33 700 Sample 11 Hydrogen peroxide solution + anionic surfactant 1082.8 4.2 24 200 Sample 12 Hydrogen Peroxide Solution + Cationic Surfactant 1010.3 3.5 32 150 Sample 4 Hydrogen Peroxide Solution + Nonionic Surfactant 1075.21 4.0 26.0 0

Comparing the results of Table 2, it can be seen that when the hydrogen peroxide solution and the nonionic surfactant are used, the properties shown are superior to the case of using the existing hydrogen peroxide solution alone or the surfactant alone.

In particular, when the hydrogen peroxide aqueous solution and the nonionic surfactants are used in combination, it can be seen that the properties are superior to the case where the hydrogen peroxide aqueous solution and the anionic surfactant or cationic surfactant is used in combination.

Example 3

This example was performed to measure the extent of restoring contaminated soil using a composition for restoring contaminated soil using various nonionic surfactants.

First, ferric sulfate (4 wt% aqueous solution) was added to contaminated soil, and a composition for restoring contaminated soil prepared by adding 700 ppm of the nonionic surfactant shown in the following Table 3 in an aqueous 5 wt% hydrogen peroxide solution was prepared.

2 kg of artificially contaminated soil was placed in a cylindrical PE container having a diameter of 2 L, and the contaminated soil restorative composition was sprayed from the upper part of the contaminated soil at 200 ml intervals for 24 hours and the concentration of contaminants after 24 hours. Was measured.

Hydrogen peroxide is a product of Hansol Chemical Co., Ltd., and TPH analysis was performed using SHIMADZU 2010 gas chromatography of Gyeongsang National University Institute of Agriculture and Life Sciences.

Nonionic surfactant Initial TPM Concentration (ppm) TPH concentration after treatment (ppm) Kinds Usage (g) Sample 13 Polyoxyethylene octylphenyl ether 0.5 10,000 869 Sample 14 Polyoxyethylene nonylphenyl ether 0.5 10,000 1198 Sample 15 Polyoxyethylene lauryl ether 0.5 10,000 1571

As shown in Table 3, as a result of using a variety of nonionic surfactants showed a similar pollutant treatment capacity, it was confirmed that all of them are reduced within the soil pollution standard.

From the above results, it can be seen that the restoration of contaminated soil is effectively performed when the hydrogen peroxide aqueous solution and the nonionic surfactant are mixed and used.

Example 4

This example was performed in order to measure the effect of the presence of surfactant injection in the aqueous hydrogen peroxide solution after injecting iron salt directly into the soil.

The results of the treatment by OO company by mixing the iron catalyst in the soil contaminated with the diesel fuel of Pohang OO reservoir by injector and then injecting the contaminated soil restoration composition into the well inserted into the soil are shown in Table 5 below. Indicated. At this time, the amount of the nonionic surfactant was 15 kg.

Polluted soil volume: 40 ㎥

Hydrogen Peroxide Consumption: 3000 ㎏

Type and amount of iron salt: FeSO ₄ · 7H ₂ O, 100 ㎏

Hydrogen peroxide is a product of Hansol Chemical Co., Ltd. The nonionic surfactant is polyoxyethylene lauryl alcohol and KINION LA-7N of Green Soft Chem is used. TPH analysis was performed using SHIMADZU 2010 gas chromatography from Gyeongsang National University Institute of Agricultural and Life Sciences.

Initial TPM Concentration (ppm) Use of iron salt Use of surfactant TPH concentration after treatment (ppm) Reduction Efficiency Sample 19 4,234 U U 787 81.41% Sample 20 10,000 U radish 4,234 57.66%

As shown in Table 4, in general, the more the treatment step of the soil contaminated with a high concentration gradually lowers the treatment efficiency, but the method of treating with the material of the present invention has a TPH reduction efficiency of the secondary treatment than the primary treatment Higher.

As a result of applying TPH to a contaminated soil site using the surfactant of the present invention, there was an effect of reducing TPH by about 40% or more.

Example 5

This example was performed to examine the degree of hydrogen peroxide savings due to the use of surfactants.

The pipes were inserted into the soil contaminated with light oil around the oil tank of the OO reservoir in Ulsan. At this time, the amount of the nonionic surfactant was 90 kg.

Polluted soil volume: about 800 ㎥

Estimated amount of hydrogen peroxide: 25000 ㎏ (Calculated the amount without surfactant)

Actual hydrogen peroxide used: 18000 ㎏ (actual amount including surfactant)

Type and amount of iron salt: FeSO ₄ · 7H ₂ O, 400 ㎏

Hydrogen peroxide is a product of Hansol Chemical Co., Ltd., and KINION LA-7N of Green Soft Chem is used as nonionic surfactant. TPH analysis was performed using SHIMADZU 2010 gas chromatography from Gyeongsang National University Institute of Agricultural and Life Sciences.

Initial TPM Concentration (ppm) Iron salt presence Presence of surfactant TPH concentration after treatment (ppm) Sample 21 3,000 U U 1,500 or less

As shown in Table 5, it can be seen that by using the composition for restoring contaminated soil of the present invention, the amount of hydrogen peroxide used was reduced by about 25% than the expected amount.

Example 6

This embodiment was performed to look at the resolution according to the type of contaminants of the composition for restoring contaminated soil of the present invention.

2 kg of soil, each artificially contaminated with benzene, toluene, ethylbenzene, xylene, and BTEX (benzene, toluene, ethylbenzene, xylene mixed material) in a 2 L diameter cylindrical container, was tested under the conditions shown in Table 7 as follows. Carried out.

The iron catalyst was ferric sulfate in a 4% by weight aqueous solution, and hydrogen peroxide in 35% by weight aqueous solution was sprayed three times from the top of the soil filled with iron salt and hydrogen peroxide at 100 ml intervals for 24 hours each to contaminate after 24 hours. The concentration of the material was measured. At this time, the amount of the nonionic surfactant was 1.5g.

As a result, it can be seen that the treatment with the soil contamination restoring composition of the present invention is much more reduced.

Hydrogen peroxide is a product of Hansol Chemical Co., Ltd., and KINION LA-7N of Green Soft Chem is used as nonionic surfactant. TPH analysis was performed using SHIMADZU 17A gas chromatography from Gyeongsang National University.

pollutant Initial concentration (ppm) Use of iron salt Use of surfactant Concentration after treatment (ppm) Sample 22 benzene 204,756 U U 58 Sample 23 toluene 138,452 U U 2,493 Sample 24 Ethylbenzene 112,442 U U 6,582 Sample 25 xylene 156,612 U U 5,318 Sample 26 BTEX 161,787 U U 2,544 Sample 27 benzene 204,756 U - 508 Sample 28 toluene 138,452 U - 3,685 Sample 29 Ethylbenzene 112,442 U - 10,075 Sample 30 xylene 156,612 U - 10,889 Sample 31 BTEX 161,787 U - 3,838

As shown in Table 6, in the case of samples 22 to 26 to which the composition for restoring contaminated soil of the present invention is applied, the residual amount of contaminants treated with the present invention as a result of restoration of contaminated soil without using the surfactant of the present invention. It can be seen that the decrease is much.

Example 7

This example presents an example of applying the composition for the restoration of contaminated soil in the field.

Yeosu oo Chemical pipes were inserted into the approximately 10,000 m3 of soil contaminated with ethylbenzene around the oil tank of the chemical tank. The result of treatment by oo with the material of the present invention while extracting the groundwater by the method of injecting three times at intervals is shown in Table 8 below. At this time, the amount of the nonionic surfactant was 15 kg.

Hydrogen peroxide is a product of Hansol Chemical Co., Ltd., and KINION LA-7N of Green Soft Chem is used as nonionic surfactant. TPH analysis was performed using SHIMADZU 17A gas chromatography from Gyeongsang National University.

Initial BTEX Concentration (ppm) Iron salt presence Presence of surfactant BTEX concentration after treatment (ppm) Sample 32 5,000 U U 80 or less Sample 33 5,000 U radish 2,150

As shown in Table 7, it can be confirmed that the decomposition of organic matter proceeded significantly when the composition for contaminating soil restoration of the present invention was applied.

As described above, by using the composition for restoring contaminated soil according to the present invention, it is possible to effectively purify and recover soil contaminated with a wide range of hardly decomposable organic substances at low cost.

Claims (3)

A composition for restoring contaminated soil, comprising 0.05 to 5% by weight of a nonionic surfactant selected from polyoxyalkylene copolymers represented by the following Formula 1 in an aqueous hydrogen peroxide solution at a concentration of 1.0 to 15.0% by weight. [Formula 1] RO- (CH ₂ CH ₂ O) _n H In Chemical Formula 1, R is an alkyl group or phenyl group having 8 to 9 carbon atoms, and n is an integer ranging from 5 to 16. delete The composition for restoring contaminated soil according to claim 1, wherein the nonionic surfactant is a biodegradable polyoxyalkylene copolymer.