JP2007209824A - Method for cleaning contaminated soil or contaminated groundwater - Google Patents
Method for cleaning contaminated soil or contaminated groundwater Download PDFInfo
- Publication number
- JP2007209824A JP2007209824A JP2005290861A JP2005290861A JP2007209824A JP 2007209824 A JP2007209824 A JP 2007209824A JP 2005290861 A JP2005290861 A JP 2005290861A JP 2005290861 A JP2005290861 A JP 2005290861A JP 2007209824 A JP2007209824 A JP 2007209824A
- Authority
- JP
- Japan
- Prior art keywords
- contaminated
- soil
- groundwater
- benzene
- pyrite
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Processing Of Solid Wastes (AREA)
- Treatment Of Water By Oxidation Or Reduction (AREA)
- Fire-Extinguishing Compositions (AREA)
Abstract
Description
本発明は、汚染土壌または汚染地下水の浄化方法に関し、特に、油分や揮発性有機化合物などの有機化合物により汚染された汚染土壌や汚染地下水の浄化方法に関する。 The present invention relates to a method for purifying contaminated soil or contaminated groundwater, and more particularly to a method for purifying contaminated soil or contaminated groundwater contaminated with organic compounds such as oil and volatile organic compounds.
ガソリンスタンド、製油所、化学工場などの跡地では、油分や揮発性有機化合物などの有機化合物により土壌や地下水が汚染されている場合があり、このような跡地を再利用する際に土壌や地下水を浄化することが必要になる場合がある。 In past sites such as gas stations, refineries, and chemical factories, soil and groundwater may be contaminated by organic compounds such as oil and volatile organic compounds. It may be necessary to purify.
油分や揮発性有機化合物などの有機化合物により汚染された土壌や地下水を浄化するために一般に行われている方法として、微生物を利用するバイオレメディエーション法や、汚染された土壌を掘削した後に焼却処理する方法などがある。 Common methods for purifying soil and groundwater contaminated with organic compounds such as oil and volatile organic compounds include bioremediation methods using microorganisms and incineration after excavating contaminated soil. There are methods.
また、難分解性有機物で汚染された土壌の修復方法として、土壌に過酸化水素を注入するとともに触媒として鉄化合物を注入することによって土壌中の難分解性有害有機物を酸化分解する方法が提案されている（例えば、特許文献１参照）。この方法では、鉄イオンの存在下で過酸化水素を作用させることにより、以下に示すようなフェントン反応によって酸化力が非常に強い水酸基ラジカル（・ＯＨ）を生成し、土壌中に存在する有機化合物を酸化分解することができる。
Ｈ２Ｏ２＋Ｆｅ２＋ → Ｆｅ３＋＋ＯＨ−＋・ＯＨ
As a method for repairing soil contaminated with persistent organic substances, a method has been proposed in which hydrogen peroxide is injected into the soil and an iron compound is injected as a catalyst to oxidize and decompose persistent organic substances in the soil. (For example, refer to Patent Document 1). In this method, hydrogen peroxide is allowed to act in the presence of iron ions, thereby generating hydroxyl radicals (.OH) with very strong oxidizing power by the Fenton reaction as shown below, and organic compounds present in the soil Can be oxidatively decomposed.
H 2 O 2 + Fe 2+ → Fe 3+ + OH - + · OH
しかし、バイオレメディエーション法では、汚染土壌を浄化するために非常に長い時間を要する。一方、汚染土壌を掘削して焼却処理する方法では、汚染土壌の掘削や運搬の際に揮発性有機化合物が揮発するという問題がある。また、汚染土壌を掘削して焼却処理する方法は、汚染土壌を掘削して場外において行う処理（場外処理）であり、原位置で処理（現地処理）を行うことができず、また、汚染地下水を浄化することもできない。 However, in the bioremediation method, it takes a very long time to purify the contaminated soil. On the other hand, the method of excavating and incinerating contaminated soil has a problem that volatile organic compounds volatilize when excavating and transporting contaminated soil. In addition, the method of excavating contaminated soil and incineration is a process performed by excavating contaminated soil and performing off-site treatment (off-site treatment), and cannot be performed in situ (on-site treatment). It cannot be purified.
また、特許文献１に提案された方法では、酸化剤として過酸化水素を使用するとともに、触媒として硫酸第一鉄などの鉄塩または鉄化合物などを使用している。この方法では、安価であること、有機化合物の分解能力に優れていること、環境への影響が懸念される塩素などのハロゲンを含んでいないことなどの理由から、一般に触媒として硫酸第一鉄を使用している。 In the method proposed in Patent Document 1, hydrogen peroxide is used as an oxidizing agent, and an iron salt or iron compound such as ferrous sulfate is used as a catalyst. In this method, ferrous sulfate is generally used as a catalyst because it is inexpensive, has an excellent ability to decompose organic compounds, and does not contain halogens such as chlorine, which are feared to affect the environment. I use it.
この方法で触媒として硫酸第一鉄を使用する場合には、硫酸第一鉄を水に溶かして鉄水溶液にした後、過酸化水素とともに地下に注入される。しかし、硫酸第一鉄を使用する場合には、過酸化水素が硫酸第一鉄と急激に反応して急激に消費されるので、反応時間が短いという問題がある。また、汚染土壌または汚染地下水に存在する有機化合物を浄化するためには、過酸化水素と鉄イオンが反応することによって発生した水酸基ラジカルが有機化合物と接触しなければならないが、反応時間が短いと、汚染土壌や汚染地下水中を浸透する前に反応が終了してしまうため、浄化範囲を広げることができない。したがって、汚染土壌または汚染地下水の浄化範囲を広くするためには、反応時間を長くすることが必要になる。 When ferrous sulfate is used as a catalyst in this method, ferrous sulfate is dissolved in water to form an aqueous iron solution and then injected into the basement together with hydrogen peroxide. However, when ferrous sulfate is used, since hydrogen peroxide reacts rapidly with ferrous sulfate and is consumed rapidly, there is a problem that the reaction time is short. In order to purify organic compounds present in contaminated soil or contaminated groundwater, hydroxyl radicals generated by the reaction of hydrogen peroxide and iron ions must come into contact with organic compounds. Because the reaction ends before penetrating contaminated soil or contaminated groundwater, the purification range cannot be expanded. Therefore, in order to increase the purification range of contaminated soil or contaminated groundwater, it is necessary to increase the reaction time.
したがって、本発明は、このような従来の問題点に鑑み、現地処理を行うことができ、油分や揮発性有機化合物により汚染された土壌または地下水を効率的に浄化することができ且つその浄化効果を長時間持続することができる、汚染土壌または汚染地下水の浄化方法を提供することを目的とする。 Therefore, in view of such conventional problems, the present invention can perform on-site treatment, can efficiently purify soil or groundwater contaminated with oil and volatile organic compounds, and its purification effect. It is an object of the present invention to provide a method for purifying contaminated soil or contaminated groundwater that can last for a long time.
本発明者らは、上記課題を解決するために鋭意研究した結果、油分および揮発性有機化合物などの有機化合物を含有する汚染土壌または汚染地下水に、過酸化物と硫化鉱物を添加することにより、汚染土壌または汚染地下水の浄化の効率とその反応持続性を向上させることができることを見出し、本発明を完成するに至った。 As a result of intensive studies to solve the above problems, the present inventors have added peroxide and sulfide minerals to contaminated soil or contaminated groundwater containing organic compounds such as oil and volatile organic compounds, The present inventors have found that the efficiency of purification of contaminated soil or contaminated groundwater and the sustainability of the reaction can be improved, and the present invention has been completed.
すなわち、本発明による汚染土壌または汚染地下水の浄化方法は、ベンゼンのような揮発性有機化合物などの有機化合物を含有する土壌または地下水に、過酸化水素などの過酸化物と、黄鉄鉱または黄銅鉱などの硫化鉱物とを添加することを特徴とする。 That is, in the method for purifying contaminated soil or contaminated groundwater according to the present invention, a soil or groundwater containing an organic compound such as volatile organic compound such as benzene, peroxide such as hydrogen peroxide, pyrite or chalcopyrite, etc. It is characterized by adding a sulfide mineral.
本発明によれば、油分および揮発性有機化合物などの有機化合物を含有する汚染土壌または汚染地下水に、黄鉄鉱や黄銅鉱などの硫化鉱物と過酸化物を添加することにより、硫化鉱物が水と反応して徐々に溶解して過酸化水素と反応し、緩やか反応することができるので、反応時間を長くすることができ、汚染土壌または汚染地下水の浄化効率を高めることができる。 According to the present invention, sulfide minerals react with water by adding sulfide minerals and peroxides such as pyrite and chalcopyrite to contaminated soil or contaminated groundwater containing organic compounds such as oil and volatile organic compounds. Then, it gradually dissolves and reacts with hydrogen peroxide and can react slowly, so that the reaction time can be lengthened and the purification efficiency of contaminated soil or contaminated groundwater can be increased.
本発明による汚染土壌または汚染地下水の浄化方法の実施の形態では、ベンゼンなどの有機化合物により汚染された汚染土壌または汚染地下水に、酸化剤として過酸化水素などの過酸化物を添加するとともに、触媒として黄鉄鉱または黄銅鉱などの硫化鉱物を添加する。 In the embodiment of the method for purifying contaminated soil or groundwater according to the present invention, a peroxide such as hydrogen peroxide is added as an oxidizing agent to the contaminated soil or groundwater contaminated with an organic compound such as benzene, and a catalyst. Add sulfide minerals such as pyrite or chalcopyrite.
触媒としては、黄鉄鉱や黄銅鉱など、鉄や銅などの金属を含有する硫化鉱物を使用することができるが、浄化効率や費用、環境への負荷を考慮すると、黄鉄鉱または黄銅鉱を使用するのが好ましい。 As the catalyst, sulfide minerals containing metals such as iron and copper such as pyrite and chalcopyrite can be used, but pyrite or chalcopyrite is used in consideration of purification efficiency, cost, and environmental impact. Is preferred.
触媒として鉄粉を使用する場合には、鉄はほとんど水に溶けないので、過酸化水素と反応する鉄イオンが存在しないため、酸を添加するなどの方法によってｐＨを低下させて鉄を溶解させる必要がある。しかし、触媒として黄鉄鉱を使用する場合には、黄鉄鉱もほとんど水に溶けないが、酸素を含む水に対しては、黄鉄鉱の表面が酸化して徐々に鉄が溶解する。すなわち、触媒として黄鉄鉱を使用すると、酸化剤として過酸化水素を使用する場合に、黄鉄鉱の表面が酸化して徐々に鉄が溶出する。この溶出した鉄イオンの存在下で過酸化水素を作用させることにより、フェントン反応によって酸化力が非常に強い水酸基ラジカル（・ＯＨ）を生成し、土壌中に存在する有機化合物を酸化分解することができる。特に、黄鉄鉱は、酸性領域では安定であり、溶解度が低いので、触媒として黄鉄鉱を使用すると、酸化剤として過酸化水素を使用する場合に、汚染物質の分解量に対する過酸化水素の使用量を少なくすることができ、そのため、反応持続性を向上させることができる。このように、黄鉄鉱は、酸性側で安定であるので、フェントン反応により溶液が酸性化しても、黄鉄鉱のまま存在し、一度に鉄が溶出したり、表面が錆びて鉄を溶出しなくなったりせずに、徐々に鉄を溶出させることができる。 When iron powder is used as a catalyst, iron hardly dissolves in water, so there is no iron ion that reacts with hydrogen peroxide, so the pH is lowered by a method such as adding acid to dissolve iron. There is a need. However, when pyrite is used as a catalyst, pyrite hardly dissolves in water. However, for water containing oxygen, the surface of pyrite is oxidized and iron is gradually dissolved. That is, when pyrite is used as a catalyst, the surface of pyrite is oxidized and iron is gradually eluted when hydrogen peroxide is used as an oxidizing agent. When hydrogen peroxide is allowed to act in the presence of the eluted iron ions, hydroxyl radicals (.OH) with very strong oxidizing power are generated by the Fenton reaction, and the organic compounds present in the soil can be oxidatively decomposed. it can. In particular, pyrite is stable in the acidic region and has low solubility. Therefore, when pyrite is used as a catalyst, when hydrogen peroxide is used as an oxidizing agent, the amount of hydrogen peroxide used is less than the amount of pollutants decomposed. Therefore, the reaction persistence can be improved. In this way, pyrite is stable on the acidic side, so even if the solution is acidified by the Fenton reaction, it remains as pyrite, and iron may elute at once, or the surface may rust and not elute iron. Without being able to elute iron gradually.
また、触媒として硫酸第一鉄を使用する場合には、ｐＨが低い領域でもフェントン反応によって水酸化物が生じて溶液中の鉄の量が減少するため、フェントン反応が止まって効率が悪くなり、反応時間も短くなる。また、土壌中では、生成した水酸化物によって目詰まりが起こり、注入効率が低下するという問題もある。しかし、黄鉄鉱を使用する場合には、ｐＨが低くても水酸化物が発生せずに反応が継続し、土壌中でも目詰まりが生じないので、フェントン反応によって土壌中に存在する有機化合物を酸化分解するためには、酸化剤として黄鉄鉱を使用するのが好ましい。 In addition, when using ferrous sulfate as a catalyst, hydroxide is generated by the Fenton reaction even in a low pH region, and the amount of iron in the solution is reduced. The reaction time is also shortened. In addition, in the soil, there is a problem that clogging occurs due to the generated hydroxide and the injection efficiency is lowered. However, when pyrite is used, the reaction continues without generating hydroxide even at a low pH, and clogging does not occur in the soil. Therefore, the Fenton reaction oxidizes and decomposes organic compounds present in the soil. In order to do so, it is preferable to use pyrite as the oxidizing agent.
また、触媒として黄鉄鉱を使用する場合には、黄鉄鉱が鉱石であり、塊状の場合もあるので、その場合には、粉状に粉砕して使用する。黄鉄鉱の粒径は、土壌や地下水への添加の形態によって適宜調整すればよい。一般に１ｍｍ以下程度の粒径がよいが、粒径が小さいと反応効率が高くなる。具体的には、種々の土壌に適用することができるように、１００μｍより小さいのが好ましく、２５μｍより小さいのが特に好ましい。また、黄鉄鉱は、反応持続性を向上させるために、鉄や硫黄の化合物であるのが好ましい。 Further, when pyrite is used as a catalyst, pyrite is an ore and may be in the form of a lump. In that case, the pyrite is used after being pulverized into a powder. What is necessary is just to adjust the particle size of pyrite suitably according to the form of addition to soil or groundwater. In general, a particle size of about 1 mm or less is good, but if the particle size is small, the reaction efficiency increases. Specifically, it is preferably less than 100 μm and particularly preferably less than 25 μm so that it can be applied to various soils. In addition, pyrite is preferably an iron or sulfur compound in order to improve reaction sustainability.
また、酸化剤としては、過酸化水素の他に、過酸化ナトリウムや過酸化カルシウムなどの過酸化物、過炭酸塩、過マンガン酸塩などを使用することができる。 In addition to hydrogen peroxide, peroxides such as sodium peroxide and calcium peroxide, percarbonates and permanganates can be used as the oxidizing agent.
また、浄化対象となる土壌や地下水に含まれる有機化合物としては、ベンゼンの他に、例えば、（１）ガソリン、灯油、軽油、重油、機械油などの石油および留分、（２）トルエン、キシレン、クロロベンゼン、フルオロベンゼン、ベンゾニトリル、フェノール、トルオール、カテコール、ビフェニル、キノリン、ジベンゾフラン、ナフタレン、アントラセン、フルオレン、ピレン、フェナントレン、アセナフテン、カルバゾールなどの芳香族化合物類、（３）トリクロロエチレン、テトラクロロエチレン、テトラクロロエタン、トリクロロエタン、クロロベンゼン類、クロロナフタレン類、ヘキサクロロシクロヘキサン、ポリクロロビフェニルなどの有機塩素化合物類、（４）ジクロロフェニルトリクロロエタン、ベンゼンヘキサクロライド、クレゾール、チウラム、シマジン、イソキサチオン、ダイアジノン、フェニトロチオン、クロルビリホス、トリルクロルホン、ブタホミス、プロピザミドなどの農薬・防虫剤などが挙げられる。 In addition to benzene, organic compounds contained in soil and groundwater to be purified include, for example, (1) petroleum and fractions such as gasoline, kerosene, light oil, heavy oil, and machine oil, and (2) toluene and xylene. , Aromatic compounds such as chlorobenzene, fluorobenzene, benzonitrile, phenol, toluol, catechol, biphenyl, quinoline, dibenzofuran, naphthalene, anthracene, fluorene, pyrene, phenanthrene, acenaphthene, carbazole, (3) trichloroethylene, tetrachloroethylene, tetrachloroethane , Trichlorethane, chlorobenzenes, chloronaphthalenes, hexachlorocyclohexane, polychlorinated biphenyls and other organic chlorine compounds, (4) dichlorophenyl trichloroethane, benzene hexachloro , Cresol, thiuram, simazine, isoxathion, diazinon, fenitrothion, Kurorubirihosu, tolyl chloro Hong, Butahomisu, like pesticides, insect repellents, such as propyzamide.
酸化剤や触媒を土壌に添加する方法としては、地上から地下に浸透させる方法、重機により汚染土壌を掘削して埋め戻し時に添加する方法、掘削後にパイル状に盛土してから添加する方法、掘削後に混練機を使用して混合する方法、井戸を掘って直接地下に注入する方法、パイプを地下に差し込んで圧力注入する方法、オーガーなどにより直接混合する方法などの種々の方法が挙げられる。また、過酸化物は、霧状または液状に注入可能なポンプと保存容器を使用して添加することができ、硫化鉱物は、スラリー状または粉体として添加することができる。また、地下水に過酸化物や硫化鉱物を添加する方法としては、地下水を汲み上げて容器内で添加する方法、井戸または注入管を地下水層まで到達させて添加する方法などを使用することができる。 As a method of adding oxidant and catalyst to soil, a method of infiltrating from the ground to the ground, a method of excavating contaminated soil with heavy machinery and adding it at the time of backfilling, a method of adding after embedding in a pile shape after excavation, excavation Various methods such as a method of mixing using a kneader later, a method of digging a well and directly injecting into the underground, a method of inserting a pipe into the underground and injecting pressure, and a method of directly mixing with an auger or the like can be mentioned. The peroxide can be added using a pump and a storage container that can be injected in the form of a mist or liquid, and the sulfide mineral can be added as a slurry or powder. In addition, as a method of adding peroxide or sulfide mineral to groundwater, a method of pumping up groundwater and adding it in a container, a method of adding a well or an injection pipe to the groundwater layer, and the like can be used.
以下、本発明による汚染土壌または汚染地下水の浄化方法の実施例として、ベンゼン溶液中のベンゼンを分解させる方法について詳細に説明する。 Hereinafter, a method for decomposing benzene in a benzene solution will be described in detail as an example of a method for purifying contaminated soil or contaminated groundwater according to the present invention.
［実施例１］
まず、粉末状の黄鉄鉱を用意した。この黄鉄鉱の粒度をレーザー回析型粒度分布測定装置によって測定したところ、９９％の質量で３〜３０μｍであり、平均粒径Ｄ５０（質量累積曲線における５０％質量の値）が１２μｍであった。また、黄鉄鉱の組成は、Ｆｅが５０％、Ｓが４２％であり、純水なＦｅＳ２ではなく、ＦｅＳとＦｅＳ２の混合物であった。また、黄鉄鉱の比表面積ＢＥＴをガス置換法により測定したところ、１．０ｍ２／ｇであった。
[Example 1]
First, powdery pyrite was prepared. When the particle size of the pyrite was measured by a laser diffraction type particle size distribution measuring device, it was 3 to 30 μm in 99% mass, and the average particle size D 50 (value of 50% mass in the mass cumulative curve) was 12 μm. . The composition of pyrite was 50% Fe and 42% S, and was not pure water FeS 2 but a mixture of FeS and FeS 2 . Moreover, it was 1.0 m < 2 > / g when the specific surface area BET of pyrite was measured by the gas substitution method.
次に、１２４ｍｌのバイアル瓶に５０ｍｌのイオン交換水を入れ、上記の粉末状の黄鉄鉱（鉄濃度０．１５ｍｏｌ／ｌ）０．８６ｇを添加し、ライナー付きブチルゴムセプタムおよびアルミシールで密封した。次いで、ブチルゴムセプタムを通じて、バイアル瓶中のベンゼン濃度が１７５ｍｇ／ｌとなるようにベンゼンをシリンジで注入した後、過酸化水素濃度が０．３ｍｏｌ／ｌになるように過酸化水素をシリンジで添加し、３０分間振とう攪拌しながら反応させた。 Next, 50 ml of ion-exchanged water was placed in a 124 ml vial, 0.86 g of the above-mentioned powdery pyrite (iron concentration 0.15 mol / l) was added, and sealed with a butyl rubber septum with a liner and an aluminum seal. Next, through a butyl rubber septum, benzene was injected with a syringe so that the benzene concentration in the vial was 175 mg / l, and then hydrogen peroxide was added with a syringe so that the hydrogen peroxide concentration was 0.3 mol / l. , Reacted for 30 minutes with shaking and stirring.
反応後にバイアル瓶のヘッドスペース中のガスを採取して、ガスクロマトグラフ質量分析法によりベンゼン濃度を測定するとともに、反応後のｐＨを測定したところ、ベンゼン濃度は０．０１ｍｇ／ｌ未満まで減少し、反応後のｐＨは２．１であった。 After the reaction, the gas in the head space of the vial was collected, and the benzene concentration was measured by gas chromatography mass spectrometry and the pH after the reaction was measured. As a result, the benzene concentration decreased to less than 0.01 mg / l, The pH after the reaction was 2.1.
その後、バイアル瓶中のベンゼン濃度が１７５ｍｇ／ｌとなるように再度ベンゼンをシリンジで注入し、３０分間振とう攪拌しながら反応させた後、同様の方法によりベンゼン濃度とｐＨを測定したところ、ベンゼン濃度は１００ｍｇ／ｌまで減少し、反応後のｐＨは２．１であった。 Thereafter, benzene was injected again with a syringe so that the benzene concentration in the vial was 175 mg / l, and the reaction was carried out with shaking and stirring for 30 minutes, and then the benzene concentration and pH were measured by the same method. The concentration was reduced to 100 mg / l and the pH after reaction was 2.1.
［実施例２］
過酸化水素濃度を０．０３ｍｏｌ／ｌにした以外は実施例１と同様の処理を行ってベンゼン濃度とｐＨを測定したところ、３０分間の反応後のベンゼン濃度が０．０２ｍｇ／ｌまで減少し、ｐＨは２．０であった。
[Example 2]
Except that the hydrogen peroxide concentration was changed to 0.03 mol / l, the same treatment as in Example 1 was carried out to measure the benzene concentration and pH. As a result, the benzene concentration after 30 minutes of reaction decreased to 0.02 mg / l. The pH was 2.0.
［比較例１］
過酸化水素を添加しなかった以外は実施例１と同様の処理を行ってベンゼン濃度を測定したところ、ベンゼン濃度は１７７ｍｇ／ｌであり、ベンゼン濃度は減少していなかった。また、ｐＨは２．４であった。
[Comparative Example 1]
When the benzene concentration was measured by performing the same treatment as in Example 1 except that hydrogen peroxide was not added, the benzene concentration was 177 mg / l, and the benzene concentration was not decreased. The pH was 2.4.
実施例１、２および比較例１の結果から、ベンゼン溶液中に過酸化水素と黄鉄鉱を添加して反応させることにより、ベンゼンを分解することができるのがわかる。また、ベンゼンを再度添加して反応させた後でもベンゼンを分解することができることから、ベンゼン分解効果が３０分経過後も持続しているのがわかる。なお、ｐＨが低くなっているのは、黄鉄鉱が水と反応した際に硫酸が生じているためである。 From the results of Examples 1 and 2 and Comparative Example 1, it can be seen that benzene can be decomposed by adding hydrogen peroxide and pyrite to the benzene solution for reaction. Moreover, since benzene can be decomposed even after benzene is added again and reacted, it can be seen that the benzene decomposition effect is maintained even after 30 minutes. The reason why the pH is low is that sulfuric acid is produced when pyrite reacts with water.
[比較例２〜４]
黄鉄鉱の代わりに２ｇの硫酸第一鉄七水和物（ＦｅＳＯ４・７Ｈ２Ｏ）（鉄濃度０．１５ｍｏｌ／ｌ）を添加した以外は実施例１、２および比較例１と同様の処理を行ってベンゼン濃度とｐＨを測定した。その結果、過酸化水素濃度が０．３ｍｏｌ／ｌの比較例２では、３０分間の反応後のベンゼン濃度が０．０４ｍｇ／ｌまで減少し、ｐＨは１．８であり、再度ベンゼンを添加して反応させた後では、ベンゼン濃度が１３５ｍｇ／ｌまで減少し、ｐＨは１．８であった。また、過酸化水素濃度が０．０３ｍｏｌ／ｌの比較例３では、３０分間の反応後のベンゼン濃度が９４ｍｇ／ｌまでしか減少せず、ｐＨは２．１であった。さらに、過酸化水素濃度を添加しなかった比較例４では、３０分間の反応後のベンゼン濃度が１９１ｍｇ／ｌであり、ｐＨは３．３であった。
[Comparative Examples 2 to 4]
The same treatment as in Examples 1 and 2 and Comparative Example 1 was conducted except that 2 g of ferrous sulfate heptahydrate (FeSO 4 .7H 2 O) (iron concentration 0.15 mol / l) was added instead of pyrite. The benzene concentration and pH were measured. As a result, in Comparative Example 2 where the hydrogen peroxide concentration was 0.3 mol / l, the benzene concentration after the reaction for 30 minutes decreased to 0.04 mg / l, the pH was 1.8, and benzene was added again. After the reaction, the benzene concentration decreased to 135 mg / l and the pH was 1.8. Further, in Comparative Example 3 in which the hydrogen peroxide concentration was 0.03 mol / l, the benzene concentration after the reaction for 30 minutes was reduced only to 94 mg / l, and the pH was 2.1. Furthermore, in Comparative Example 4 in which no hydrogen peroxide concentration was added, the benzene concentration after the reaction for 30 minutes was 191 mg / l, and the pH was 3.3.
硫酸第一鉄を添加した比較例２および３と比べて、黄鉄鉱を添加した実施例１および２では、ベンゼンの分解量が多いので、ベンゼンの分解作用に優れていることがわかる。なお、比較例２および３では、添加した過酸化水素が硫酸第一鉄と急激に反応して、過酸化水素が水中のベンゼンと接触する前に消費されていると考えられる。 Compared with Comparative Examples 2 and 3 in which ferrous sulfate was added, in Examples 1 and 2 in which pyrite was added, the amount of benzene decomposed was large, indicating that the decomposition action of benzene was excellent. In Comparative Examples 2 and 3, it is considered that the added hydrogen peroxide reacts rapidly with ferrous sulfate and is consumed before it comes into contact with benzene in water.
[比較例５〜７]
黄鉄鉱の代わりに０．４ｇの鉄粉（ＦｅＯ）（鉄濃度０．１５ｍｏｌ／ｌ）を添加した以外は実施例１、２および比較例１と同様の処理を行って３０分間の反応後のベンゼン濃度を測定した。その結果、比較例５および６では、ベンゼン濃度がそれぞれ１６５ｍｇ／ｌおよび１６８ｍｇ／ｌであり、ベンゼンがほとんど分解していなかった。これは、鉄粉を使用する場合には、鉄がほとんど水に溶解しないため、過酸化水素と反応する鉄イオンが存在しないためであると考えられる。また、ｐＨはそれぞれ６．９および７．７であった。したがって、比較例５および６のように鉄粉を使用する場合には、酸を添加するなどの方法によりｐＨを低下させて鉄を溶解する必要がある。一方、実施例１および２のように黄鉄鉱を使用する場合には、水と反応させた状態でｐＨが２．４であるため、酸を添加する必要はなく、作業効率に優れている。なお、比較例７では、ベンゼン濃度が１７８ｍｇ／ｌであり、ｐＨが９．１であった。また、比較例５〜７では、ベンゼンが分解しなかったので、再度ベンゼンを添加する処理は行わなかった。
[Comparative Examples 5 to 7]
Benzene after reaction for 30 minutes by performing the same treatment as in Examples 1 and 2 and Comparative Example 1 except that 0.4 g of iron powder (FeO) (iron concentration 0.15 mol / l) was added instead of pyrite. Concentration was measured. As a result, in Comparative Examples 5 and 6, the benzene concentrations were 165 mg / l and 168 mg / l, respectively, and benzene was hardly decomposed. This is considered to be because when iron powder is used, iron hardly dissolves in water, and there is no iron ion that reacts with hydrogen peroxide. The pH was 6.9 and 7.7, respectively. Therefore, when iron powder is used as in Comparative Examples 5 and 6, it is necessary to lower the pH by a method such as adding an acid to dissolve iron. On the other hand, when pyrite is used as in Examples 1 and 2, the pH is 2.4 when reacted with water, so there is no need to add an acid and the working efficiency is excellent. In Comparative Example 7, the benzene concentration was 178 mg / l, and the pH was 9.1. Moreover, in Comparative Examples 5-7, since benzene did not decompose | disassemble, the process which adds benzene again was not performed.
[比較例８、９]
触媒を添加しなかった以外は実施例１および２と同様の処理を行って３０分間の反応後のベンゼン濃度を測定したところ、それぞれ１６５ｍｇ／ｌおよび１８１ｍｇ／ｌであり、ｐＨがぞれぞれ５．３および５．９であった。これらの結果から、実施例１および２のように黄鉄鉱のような触媒を添加しなければ、ベンゼンを分解することができないことがわかる。
これらの実施例および比較例の結果を表１にまとめて示す。
[Comparative Examples 8 and 9]
Except that no catalyst was added, the same treatment as in Examples 1 and 2 was performed, and the benzene concentration after the reaction for 30 minutes was measured. As a result, the pH was 165 mg / l and 181 mg / l, respectively. 5.3 and 5.9. From these results, it is understood that benzene cannot be decomposed unless a catalyst such as pyrite is added as in Examples 1 and 2.
The results of these examples and comparative examples are summarized in Table 1.
Claims (5)
The method for purifying contaminated soil or groundwater contamination according to any one of claims 1 to 3, wherein the organic compound is benzene.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2005290861A JP2007209824A (en) | 2005-10-04 | 2005-10-04 | Method for cleaning contaminated soil or contaminated groundwater |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2005290861A JP2007209824A (en) | 2005-10-04 | 2005-10-04 | Method for cleaning contaminated soil or contaminated groundwater |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2007209824A true JP2007209824A (en) | 2007-08-23 |
Family
ID=38488699
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2005290861A Pending JP2007209824A (en) | 2005-10-04 | 2005-10-04 | Method for cleaning contaminated soil or contaminated groundwater |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2007209824A (en) |
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2009001720A1 (en) * | 2007-06-25 | 2008-12-31 | Azmec Co., Ltd. | Encapsulating agent for harmful substances and method for encapsulation of harmful substances |
| JP2009291668A (en) * | 2008-06-02 | 2009-12-17 | Hiroshima Univ | Water area environment improving material and its use |
| JP2010088991A (en) * | 2008-10-07 | 2010-04-22 | Waseda Univ | Water treatment agent and water treatment method |
| KR101084371B1 (en) * | 2009-01-20 | 2011-11-17 | (주)그린텍환경컨설팅 | Direct oxidation method using iron-bearing mineral to degrade volatile organic compounds generated from the process of contaminated soil remediation |
| JP2011230083A (en) * | 2010-04-28 | 2011-11-17 | Keiichiro Asaoka | Decomposition treatment method for organic waste, and microorganism activator used for the same |
| JP2012082618A (en) * | 2010-10-12 | 2012-04-26 | Kajima Corp | Tunnel construction method |
| IT201600093143A1 (en) * | 2016-09-15 | 2018-03-15 | Mapei Spa | METHOD FOR THE REDUCTION OF THE ORGANIC CONTENT OF THE LANDS OBTAINED IN THE FORM OF EXCAVATION MECHANIZED FOR THE REALIZATION OF GALLERIES AND WELLS |
| CN108675432A (en) * | 2018-06-07 | 2018-10-19 | 中国地质大学（北京） | A kind of improvement Fenton medicament and apply its wastewater treatment method |
| CN112340831A (en) * | 2020-11-16 | 2021-02-09 | 郑州大学 | Device and method for rapidly degrading organic pollutants in wastewater |
| KR20210051479A (en) * | 2019-10-30 | 2021-05-10 | 서울대학교산학협력단 | A metal sulfides based oxidation system, and a method for the oxidative degradation of organic pollutants using the same |
| CN113402008A (en) * | 2021-05-28 | 2021-09-17 | 湖南大学 | Method for removing antibiotics in water body by using chalcopyrite activated percarbonate |
| KR102424682B1 (en) * | 2021-02-17 | 2022-07-22 | 안성국 | Cuprous oxide free silyl antifouling coating composition comprising pyrite |
| CN115417482A (en) * | 2022-09-16 | 2022-12-02 | 中国地质大学（武汉） | Method for reducing secondary pollutants generated by degradation of collecting agent in sulfide mine wastewater |
| WO2023175163A1 (en) | 2022-03-18 | 2023-09-21 | Wageningen Universiteit | Process for the generation of hydrogen sulfide in the presence of pyrite as catalyst |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0775772A (en) * | 1993-06-18 | 1995-03-20 | Kankyo Eng Kk | Method for restoring soil |
| JP2004042011A (en) * | 2002-07-15 | 2004-02-12 | Toru Ueda | Early purification method for petroleum-contaminated soil using burnt lime, and greening method |
-
2005
- 2005-10-04 JP JP2005290861A patent/JP2007209824A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0775772A (en) * | 1993-06-18 | 1995-03-20 | Kankyo Eng Kk | Method for restoring soil |
| JP2004042011A (en) * | 2002-07-15 | 2004-02-12 | Toru Ueda | Early purification method for petroleum-contaminated soil using burnt lime, and greening method |
Cited By (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2009001720A1 (en) * | 2007-06-25 | 2008-12-31 | Azmec Co., Ltd. | Encapsulating agent for harmful substances and method for encapsulation of harmful substances |
| JP2009291668A (en) * | 2008-06-02 | 2009-12-17 | Hiroshima Univ | Water area environment improving material and its use |
| JP2010088991A (en) * | 2008-10-07 | 2010-04-22 | Waseda Univ | Water treatment agent and water treatment method |
| KR101084371B1 (en) * | 2009-01-20 | 2011-11-17 | (주)그린텍환경컨설팅 | Direct oxidation method using iron-bearing mineral to degrade volatile organic compounds generated from the process of contaminated soil remediation |
| JP2011230083A (en) * | 2010-04-28 | 2011-11-17 | Keiichiro Asaoka | Decomposition treatment method for organic waste, and microorganism activator used for the same |
| JP2012082618A (en) * | 2010-10-12 | 2012-04-26 | Kajima Corp | Tunnel construction method |
| IT201600093143A1 (en) * | 2016-09-15 | 2018-03-15 | Mapei Spa | METHOD FOR THE REDUCTION OF THE ORGANIC CONTENT OF THE LANDS OBTAINED IN THE FORM OF EXCAVATION MECHANIZED FOR THE REALIZATION OF GALLERIES AND WELLS |
| CN108675432A (en) * | 2018-06-07 | 2018-10-19 | 中国地质大学（北京） | A kind of improvement Fenton medicament and apply its wastewater treatment method |
| KR102346182B1 (en) * | 2019-10-30 | 2021-12-31 | 서울대학교산학협력단 | A metal sulfides based oxidation system, and a method for the oxidative degradation of organic pollutants using the same |
| KR20210051479A (en) * | 2019-10-30 | 2021-05-10 | 서울대학교산학협력단 | A metal sulfides based oxidation system, and a method for the oxidative degradation of organic pollutants using the same |
| CN112340831A (en) * | 2020-11-16 | 2021-02-09 | 郑州大学 | Device and method for rapidly degrading organic pollutants in wastewater |
| CN112340831B (en) * | 2020-11-16 | 2024-03-26 | 郑州大学 | Device and method for rapidly degrading organic pollutants in wastewater |
| KR102424682B1 (en) * | 2021-02-17 | 2022-07-22 | 안성국 | Cuprous oxide free silyl antifouling coating composition comprising pyrite |
| CN113402008A (en) * | 2021-05-28 | 2021-09-17 | 湖南大学 | Method for removing antibiotics in water body by using chalcopyrite activated percarbonate |
| CN113402008B (en) * | 2021-05-28 | 2022-02-15 | 湖南大学 | Method for removing antibiotics in water body by using chalcopyrite activated percarbonate |
| WO2023175163A1 (en) | 2022-03-18 | 2023-09-21 | Wageningen Universiteit | Process for the generation of hydrogen sulfide in the presence of pyrite as catalyst |
| NL2031328B1 (en) | 2022-03-18 | 2023-09-29 | Univ Wageningen | Process for the generation of hydrogen sulfide in the presence of pyrite as catalyst |
| CN115417482A (en) * | 2022-09-16 | 2022-12-02 | 中国地质大学（武汉） | Method for reducing secondary pollutants generated by degradation of collecting agent in sulfide mine wastewater |
| CN115417482B (en) * | 2022-09-16 | 2023-11-03 | 中国地质大学（武汉） | Method for reducing secondary pollutants generated by degradation of collecting agent in sulfide mine wastewater |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP2007209824A (en) | Method for cleaning contaminated soil or contaminated groundwater | |
| CA2555484C (en) | Oxidation of organic compounds at high ph | |
| CN102834190B (en) | Method for oxidising organic compounds | |
| DK1667935T3 (en) | TREATMENT OF ENVIRONMENTAL CONTAMINANTS | |
| AU2014263011B2 (en) | Chemical oxidation and biological attenuation process for the treatment of contaminated media | |
| BRPI0617476A2 (en) | Oxidation method of a contaminant present in an environment, and, composition | |
| US20190262877A1 (en) | Situ Ferrate Generation | |
| US20170354837A1 (en) | Destruction of dense nonaqueous phase liquids (dnapls) using a time-release formulation | |
| US9126245B2 (en) | Chemical oxidation and biological attenuation process for the treatment of contaminated media | |
| AU2018351667B2 (en) | Method and reagent system for remediating mine waste and other solid waste contaminated with heavy metals | |
| JP4721320B2 (en) | Decomposition method of organic pollutants | |
| TWI566806B (en) | A composition for decomposing a chemical substance and a method for decomposing a chemical substance by using the composition | |
| US9616473B2 (en) | In-situ subsurface extraction and decontamination | |
| JP2006341195A (en) | Method of clarifying organic contaminant | |
| Santos et al. | Persulfate in remediation of soil and groundwater contaminated by organic compounds | |
| KR101185943B1 (en) | Triple salt composition for contaminated soil and the method of restore contaminated soil using the triple salt composition | |
| JP5888877B2 (en) | Chemical substance decomposition agent composition and chemical substance decomposition treatment method using the same | |
| Domínguez Torre et al. | Remediation of HCHs-contaminated sediments by chemical oxidation treatments | |
| KR101353429B1 (en) | Composition for purifying soil with contaminated organic compounds and method for decontaminating using thereof | |
| MXPA06009697A (en) | Oxidation of organic compounds at high ph |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20080827 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20100616 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20100713 |
|
| A02 | Decision of refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A02 Effective date: 20110104 |