• 한국응용과학기술학회지
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• 제22권2호
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• pp.136-141
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• 2005

This paper presents applicability of Fenton oxidation to perchloroethylene(PCE) contaminated soil. The initial concentration of PCE was 187mg/kg and Fenton oxidation conditions were 1.0M $H_2O_2$ and 0.5M $Fe^{2+}$. More than 97% of PCE decomposition and 98% of dechlorination were obtained within 5 hrs. It was found that the decomposition of PCE by Fenton oxidation was followed pseudo first order and its reaction coefficient was 0.78 $hr^{-1}$. GC-MS and GC-ECD analysis of reaction intermediates confirmed only the presence of trichloroacetic acid(i.e., 1.0% of initial PCE concentration). Under Fenton oxidation conditions, it was proposed that PCE was decomposed not simultaneously but one by one.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2001년도 추계학술발표회
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• pp.51-54
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• 2001

This research was carried out to evaluate feasibility of using an Electrokinetic-Fenton(EK-Fenton) technique to treat hydrophobic organic pollutant(phenanthrene) from soils. Experiment examined the effect by introducing a continuous flow of a 3.5% hydrogen peroxide solution at the anode. An electric gradient of 1V/cm was applied to enhance the saturated flow in the soil cell for a period of 11 days. After 11 days or 1 pore volume, overall concentration of residual phenanthrene in the soil cell was 11% and residual phenanathrene concentration in the soil was found to increase with toward the cathode. This results indicated that Fenton-like reaction catalyzed by mineral surface was effective in oxidizing phenanthrene. This results also showed that hydrogen peroxide was effectively transported into the soil by electroosmotic flow as well as by diffusion.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제10권S_4호
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• pp.165-172
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• 2001

We investigated the optimal experimental conditions and reaction kinetics for the decompositions of PCE, TCE, naphthalene, and chloroform using conventional Fenton oxidation process. Additionally, the influence of pH on the decompositions of PCE was also evaluated. The results indicated that the optimal pH value was around 3. The dosage of Fenton's reagent and the molar ratio of hydrogen peroxide to ferrous ion for an approximately complete decomposition was found to depend on the properties of the organic compound. Due to their unsaturated structures, the results show that PCE, TCE, and naphthalene could be all effectively decomposed by Fenton's reagent oxidation. Their unsaturated structures could be mostly destoyed within first 1-2 minutes at a low dosage with an certain molar ratio of hydrogen peroxide to ferrous ion. However the saturated compound such as chloroform was more difficult to decompose even with a relatively high dosage of Fenton's reagent.

• 한국물환경학회지
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• 제20권6호
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• pp.610-614
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• 2004

The objective of this study was to remove organics and color in livestock wastewater using coagulation and Fenton oxidation process. After coagulation process as $1^{st}$ treatment, organics in $1^{st}$ treatment water were removed by using OH radical produced in Fenton oxidation process. Removal efficiencies of $COD_{Mn}$ and color were 87.2% and 95.7% separately. At that time, the ratio of $Fe^{2+}/H_2O_2$ was 0.8~1.0, and range of reaction pH was effective at the pH of 3.5~3.8. The Reaction time of 120min more than 60min or 90min was sufficient in Fenton process. Removal efficiency of organics was higher two- or multi-stage treatment than one-stage treatment.

• 대한환경공학회지
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• 제31권5호
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• pp.352-357
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• 2009

오염토양에 펜톤 반응을 적용함에 있어서 과산화수소의 빠른 소모로 과량의 과산화수소가 요구되어지는 것이 단점으로 지적되고 있다. 이에 본 연구에서는 대표적인 PAHs물질인 phenanthrene으로 오염된 토양 처리를 위해 철의 리간드로 acetate를 사용하여 과산화수소의 안정성 확보를 통하여 공정의 효율을 높이고자 하였다. Acetate는 철의 몰농도에 대비하여 0.5배에서 3배(2${\sim}$12 mM)까지 주입하였고, 과산화수소는 분해 효율에 미치는 영향을 배제하기 위해 낮은 농도인 0.7%를 주입하였다. Acetate가 주입되어 과산화수소의 잔류시간은 최대 50배 이상 증가하였으며, 과산화수소의 안정성이 확보됨에 따라 phenanthrene의 제거율도 70%까지 향상되었다. 반응 중에 철은 2가와 3가로 산화환원을 반복하였고 과산화수소가 모두 분해되는 시점부터 $HO_2^-$에 의해 2가철로 환원이 이루어졌다. 과산화수소의 영향으로 반응중의 pH는 산성영역을 나타냈으며, acetate가 8 mM 이상 주입되었을때 4${\sim}$5범위 내에 머무르는 것을 확인하였다. Fenton reaction에 의해 철의 리간드로 사용된 acetate 역시 분해가 이루어지는 것을 확인할 수 있었으며, phenanthrene의 비해 분해되는 시점이 느린 것으로 나타나 분해되어지는 경쟁관계에서 phenanthrene이 우세한 것으로 판단된다. 이상의 연구결과를 통해 오염 토양처리에 기존 Fenton reaction의 효율성과 경제성을 향상시킬 수 있는 가능성을 확인할 수 있었으며, 중성영역의 pH로 확장된 연구 등을 통해 좀 더 현실적인 공법으로 발전할 수 있으리라 판단된다.

• 한국환경보건학회지
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• 제34권2호
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• pp.175-182
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• 2008

This study investigates the optimal conditions for electrogenerated hydrogen peroxide production and the application of the electro-Fenton process using DSA electrodes. The influences of parameters for the hydrogen peroxide generation such as electrode materials, electrolyte concentration, current, pH, air flow rate and electrode distance were investigated using a laboratory scale batch reactor. The relative performance for hydrogen peroxide generation of each of the six electrodes is : Ru-Sn-Ti > Ru-Sn-Sb > Ru > Ir > Pt > Sn-Sb. Optimum NaCl dosage, current and air flow rate were 2.0 g/l, 12.5 A and 2 l/min, respectively. When the pH is low, hydrogen peroxide concentration was high. Electrode distance dos not effect to a hydrogen peroxide generation. A complete color removal was obtained for RhB (200 mg/l) at the 8 min mark of the electro-Fenton process under optimum operation conditions of $Fe^{2+}$ 0.105 g/l and 5.0 A. The electro-Fenton process increased initial reaction and decreased final reaction time. However the effect was not high.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권7호
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• pp.25-31
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• 2013

Hydrogen peroxide takes much of the cost for Fenton reaction applied for treatment of organic contaminants. Therefore, the effective use of hydrogen peroxide makes the technology more cost effective. The effective use of hydrogen peroxide is especially needed in the soil and groundwater remediation where complete mixing is not possible and it takes a long time for reactive species to transport to the fixed target compounds. Stabilization ability for hydrogen peroxide of malonic acid was evaluated in Fenton and Fenton-like reactions in this study. Malonic acid contributes on the stabilization of hydrogen peroxide by weak interaction between iron and the stabilizer and inhibiting the catalytic role of iron. The stabilization effect increased as the solution pH decrease below the $pK_{a1}$. The stabilization effect increased as the concentration of malonic acid increased and the effect was maximized at the malonic acid concentration of about ten times higher than the iron concentration. The model organic contaminant was successfully oxidized in the presence of the stabilizer but the degradation rate was slower than the system without the stabilizer. The stabilization effect was also proved in a Fenton-like reaction where magnetite and hematite were used instead of soluble iron species.

• 한국지하수토양환경학회지:지하수토양환경
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• 제21권1호
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• pp.86-93
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• 2016

Fenton is the reaction using the OH· radicals generating by interaction between hydrogen peroxide and Fe²⁺ which can oxidize the contaminants. Fe²⁺ ions are oxidized to Fe³⁺ ions by reaction with H₂O₂ and formed OH· radicals. UV-Fenton process includes the additional reaction that generates the OH· radicals by photodegradation of H₂O₂. In methylorange (MO) decolourization experiment with UV-Fenton, optimal Fe²⁺: H₂O₂ ratio was obtained at 1 : 10. Based on the obtained condition (H₂O₂= 10mM, Fe²⁺ = 1 mM) with/without UV-fenton experiment was carried out. Removal efficiency and sludge production were measured at 30 min. The case of w/o UV irradiation and only H₂O₂ was hardly treated and only Fe²⁺ showed 65% removal owing to coagulation. When UV-Fenton process in optimal ratio (Fe²⁺: H₂O₂ = 1 : 10), UV irradiation showed better removal efficiency than of w/o UV irradiation. Also, MO decolourization was a function of the hydrogen peroxide concentration (x₁), Fe²⁺:H₂O₂ ratio (x₂), and numbers of UV lamp (x₃) from the application of the response surface methodology. Statistical results showed the order of significance of the independent variables to be hydrogen peroxide concentration > numbers of UV l amp > Fe²⁺: H₂O₂ ratio.

• 대한토목학회논문집
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• 제31권4B호
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• pp.377-382
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• 2011

본 연구에서는 modified fenton 반응에서 과산화수소를 안정화하여 오염토양 정화의 효과를 증대시키고자 하였다. 오염토양을 모사하기 위하여 PAHs 계열의 대표적인 오염물질인 phenanthrene을 사용하였다. 과수안정제로는 음이온 계면활성제인 SDS(Sodium dodecyl Sulfate)를 사용하였다. Modified Fenton 반응에서 phenanthrene의 제거율을 확인하기 위하여 Fe(II) 4 mM, SDS 5~50 mM 및 $H_2O_2$ 102.897 mM를 phenanthrene 125 mg/kg으로 오염된 토양에 주입하였다. 과수안정제인 SDS가 30 mM이 사용된 경우 phenanthrene의 제거 효율이 95%로 가장 높게 나타났으며 30 mM이싱에서는 시스템에서 SDS가 scavenger로 작용하여 오염물질의 제거효율이 SDS 30 mM 일 때 보다 낮게 나타났다. 과수안정제를 사용한 뒤 과산화수소의 농도변화를 분석한 결과 Fe(II) 2 mM에서 48시간 이후 14.6995 mM 이상 남아있어서 가장 안정적이었지만, Fe(III)을 주입한 경우에는 과산화수소가 안정화되지 않았다. Modified Fenton 반응에서 철과 SDS 농도 사이의 최적의 비율을 찾기 위하여 SDS의 농도는 30 mM로 고정하고 철의 농도를 2~8 mM로 변화시켜 실험한 결과 Fe(II) 4 mM 및 SDS 30 mM에서 약 95%의 가장 높은 제거율을 보였다.

• 한국산학기술학회논문지
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• 제7권4호
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• pp.704-708
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• 2006

경유로 오염된 인공오염토양을 효과적으로 정화하기위하여 물리 화학적 처리방법인 펜톤 산화반응과 생물학적 처리방법인 근권미생물의 활성도를 이용하는 방법을 연속적으로 적용하였다. 펜톤산화반응에서는 과산화수소의 농도가 증가할수록 TPH의 제거율이 증가하였으며 근권미생물 반응실험에서의 TPH 제거 효율은 콩(83.5%)<벼(81.5%)<대조군(76%) 순으로 나타났다.