• Applied Chemistry for Engineering
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• v.33 no.4
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• pp.419-424
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• 2022

The oxidative degradation performance of the Erionyl Navy R dye was studied in this article. The investigation mainly focused on a comparative study between chemical oxidations by sodium hypochlorite (NaClO) and hydrogen peroxide (H₂O₂), and catalytic oxidations including the Fenton (Fe²⁺-H₂O₂) and Fenton-Like (Fe²⁺/ Fe³⁺/Co²⁺/ Mn²⁺-H₂O₂) or modified Fenton-like (Fe²⁺/ Fe³⁺ -NaClO) reactions. A discoloration and degradation of the Erionyl Navy R occurred after 30 minutes, which varies according to the oxidation system involved; 31%, 54%, <20%, 95%, and >96% losses were observed for Co²⁺-H₂O₂, Mn²⁺-H₂O₂, Fe²⁺-NaClO, Fe³⁺-NaClO), and Fe²⁺-H₂O₂ and Fe³⁺-H₂O₂, respectively.

• Applied Chemistry for Engineering
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• v.16 no.1
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• pp.9-14
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• 2005

The Fenton reaction ($Fe^{2+}+H_2O_2$) has attracted considerable attention because of promising applicability as an environmental technology. While the various novel environmental technologies using Fenton reaction have been actively developed, the detailed mechanism of Fenton reaction is not clearly defined yet. As the major oxidizing chemical species, hydroxyl radical and high valent iron complex have been suggested to be produced in Fenton reaction in different mechamisms respectively. We critically summarized the basic issues regarding the microscopic mechanism of Fenton reaction.

• Bulletin of the Korean Chemical Society
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• v.27 no.4
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• pp.489-494
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• 2006

Goethite, hematite, magnetite and synthesized iron oxide are used as catalysts for Fenton-type oxidation of phenol. The synthesized iron oxides were characterized by X-ray diffraction (XRD), BET, X-ray photoelectron spectroscopy (XPS), and electron paramagnetic resonance (EPR). The catalytic activity of these materials is classified according to the observed rate of phenol oxidation. The effectiveness of the catalysts followed the sequence: ferrous ion > synthesized iron oxide >> magnetite hematite > goethite. According to these results, the most effective iron oxide catalyst had the structure similar to natural hematite. The surface oxidation state of the catalyst was between magnetite and hematite (+2.5 ~ +3.0). Phenol degraded completely in 40 min at neutral pH (pH = 7). Soluble ferric and ferrous ions were not detected in the filtrate from Fenton reaction solution by AAS. The formation of hydroxyl radicals was confirmed by EPR.

• Journal of Industrial and Engineering Chemistry
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• v.68
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• pp.14-23
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• 2018

$TiO_2-coated$ cubic ${\alpha}-Fe_2O_3$ with mostly exposed (012) and (101) facets (${\alpha}-Fe_2O_3@TiO_2$) was fabricated using a hydrothermal route for the photo-Fenton degradation of tetracycline under visible light irradiation. $TiO_2$ coating could greatly affect the photocatalytic activity of ${\alpha}-Fe_2O_3@TiO_2$. Compared with cubic ${\alpha}-Fe_2O_3$ alone for photodegradation of tetracycline, ${\alpha}-Fe_2O_3@TiO_2$ with $TiO_2$ shell of around 15 nm exhibited higher removal efficiency of tetracycline in photo-Fenton system, and its durability was slightly affected after five cycle times under same conditions. It is ascribed to the well-matched interface between cubic ${\alpha}-Fe_2O_3$ core and $TiO_2$ shell, leading to the broadened light-absorption and the efficient separation of photo-generated electon-hole pairs. The $^{\bullet}OH$ radicals were main responsible for the advanced photocatalytic performance of ${\alpha}-Fe_2O_3@TiO_2$ in visible-light driven degradation of tetracycline.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.10 no.S_4
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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.

• Journal of Microbiology and Biotechnology
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• v.16 no.11
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• pp.1734-1739
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• 2006

The degradation of perchloroethylene (PCE) was investigated with the serial treatment of biological reaction after dechlorination using Fenton's reagent. The dechlorination of PCE was expressed using $D_m$ (dechlorination value), calculated from ${\Delta}Cl^-mol/{\Delta}PCE$ mol, and was 2.58 with 5 mM of $H_2O_2$ and $Fe^{3+}$. The $150{\mu}M$ of PCE was transformed to $37{\mu}M$ of dichloroacetic acid (DCAA). Biological treatment with Delftia sp. N6 was applied after degradation of PCE by the Fenton reaction. The optical densities indicating cell growth were 0.53/0.10 with/without the Fenton reaction after one day, respectively. The N6 strain degraded 95% of the DCAA produced from PCE by the Fenton reaction within one day. Consequently, it seemed that the serial treatment of a Fenton reaction and biological reaction was effective in the removal of not only PCE, but also DCAA, one of the major metabolites of PCE.

• Applied Chemistry for Engineering
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• v.16 no.5
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• pp.693-697
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• 2005

We researched in the optimization of unit process and the stabilization of discharged water quality through the treatment of the occurrence of wastewater classified by place of production which has high COD load and non degradable COD load in paper industry. As the result, using polymer, inorganic flocculants and alum at the same time is effective to advance the COD value through the colloid material removal with SS in the first treatment process. Moreover, it is determined to keep optimum of $FeCl_2/H_2O_2$ in the concentration of 1000 ppm in the ratio of 1/1. Because It is confirmed that to input excess chemicals using Fenton oxidation method gives adverse effect to water quality.

• Bulletin of the Korean Chemical Society
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• v.1 no.3
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• pp.87-93
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• 1980

• Carbon letters
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• v.9 no.3
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• pp.195-199
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• 2008

A nanocomposite consisting of $Fe_3O_4$ and MWCNT was produced via sol-gel technique using $FeCl_3$ along with MWCNT by calcination at $300^{\circ}C$. The degradation effect of rhodamine B dye has been investigated under UV illumination in a darkroom. The degradation reaction was studied by monitoring the discoloration of dye as a function of irradiation time using UV-visible spectrophotometeric technique. The $Fe_3O_4$-MWCNT samples have continuous degradation ability under the UV illumination with the first order kinetics and the dye removal was better than in the pristine $Fe_3O_4$. The resultant composite catalyst was found to be efficient for the photo-Fenton reaction of the dye.

• Bulletin of the Korean Chemical Society
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• v.31 no.4
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• pp.803-807
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• 2010

Schorl modified by $H_2SO_4$ has been successfully developed to enhance schorl-catalyzed Fenton-like reaction for removal of phenol in an aqueous solution. The phenol removal percentage can be increased from 4% to 100% by the system of modified schorl and $H_2O_2$. Batch experiments indicate that the percent increases in removal of phenol by increasing the dosage of catalyst, temperature and initial concentration of $H_2O_2$. The results of XRD, FT-IR and SEM suggest that no new phases are formed after removal of phenol by modified schorl. ICP-AES results reveal that more dissolution of iron results in higher catalytic oxidant activity in the system of modified schorl and $H_2O_2$. Besides minor adsorption, mineral-catalyzed Fenton-like reaction governs the process.