• Journal of Soil and Groundwater Environment
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• v.18 no.7
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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.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.1
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• pp.6-12
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• 2013

TFormic acid-hydrogen peroxide (or performic acid) pulping process needs milder reaction condition than other chemical pulping process. Two-step formic acid-hydrogen peroxide pulping process can produce the chemical pulp with similar pulp yield and lignin content compared with soda-anthraquinone process. Formic acid-hydrogen peroxide pulp can be produced less xylan content than other alkaline pulps, which favor for dissolving pulp production. Formic acid-hydrogen peroxide pulp showed better response beating than soda-anthraquinone(AQ) pulps with reaching target freeness with less beating. Also, formic acid-hydrogen peroxide pulp had better tensile index at similar freeness level compared with soda-AQ pulps.

• Journal of Environmental Science International
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• v.29 no.4
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• pp.383-393
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• 2020

To increase electrolysis performance, the applicability of seawater to the iron-fed electro-Fenton process was considered. Three kinds of graphite electrodes (activated carbon fiber-ACF, carbon felt, graphite) and dimensionally stable anode (DSA) electrode were used to select a cathode having excellent hydrogen peroxide generation and organic decomposition ability. The concentration of hydrogen peroxide produced by ACF was 11.2 mg/L and those of DSA, graphite, and carbon felt cathodes were 12.9 ~ 13.9 mg/L. In consideration of durability, the DSA electrode was selected as the cathode. The optimum current density was found to be 0.11 A/㎠, the optimal Fe²⁺ dose was 10 mg/L, and the optimal ratio of Fe²⁺ dose and hydrogen peroxide was determined to be 1:1. The optimum air supply for hydrogen peroxide production and Rhodamine B (RhB) degradation was determined to be 1 L/min. The electro-Fenton process of adding iron salt to the electrolysis reaction may be shown to be more advantageous for RhB degradation than when using iron electrode to produce hydrogen peroxide and iron ion, or electro-Fenton reaction with DSA electrode after generating iron ions using an iron electrode.

• Journal of Microbiology and Biotechnology
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• v.13 no.5
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• pp.773-777
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• 2003

The color of Congo red hinders the spectrometric measurements of a concentration of hydrogen peroxide and enzyme activity (Horseradish peroxidase; HRP) during enzymatic decoloring of Congo red. In this study, a method was developed to measure peroxidase activity and hydrogen peroxide concentration in the presence of Congo red. The oxidation product of HRP/hydrogen peroxide and ABTS(2,2'-azino-bis-(3-ethylbenzotriazoline-6-sulfonic acid)) formed a dark green color. The spectrum of this product showed absorption bands at 420 nm and 734 nm. When compared with the Congo red spectrum, the absorption at 734 nm of this product did not overlap with Congo red, thus making the hydrogen peroxide measurement possible even in the presence of Congo red. Kinetic study of decoloring of Congo red performed by this method showed that the decoloring reaction followed the Michaelis-Menten kinetics. Pulse feeding of hydrogen peroxide, upon depletion, significantly increased the decoloring of Congo red. This result shows that this newly developed technique can monitor, predict, and improve the enzymatic decoloring process.

• Journal of Environmental Science International
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• v.16 no.12
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• pp.1425-1430
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• 2007

This study was conducted to investigate the effect of ozonated water and ozonated water+hydrogen peroxide treatment of residual procymidone in perilla leaf containing 20 mg/L procymidone. Samples was treated with ozonated water containing 1.0, 2.0 and 3.0 mg $O_3/L$ ozone and hydrogen peroxide water containing 1.0, 2.0 and 3.0 mg $H_2O_2/L$ hydrogen peroxide in pH 5, 7 and 9, respectively, at $15^{\circ}C$. Procymidone removal rate was 26.5% in 7 days at $15^{\circ}C$ and optimum condition of procymidone removal was the case of treating with ozonated water containing 2.0 mg $O_3/L$ and pH 9. As the result procymidone removal rate was about 96.5%. In this case of adding hydrogen peroxide, optimum condition of procymidone removal was $1:0.5{\sim}1(O_3:H_2O_2)$. However, procymidone was nearly removed with the treatment of hydrogen peroxide water only.

• BMB Reports
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• v.38 no.5
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• pp.577-583
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• 2005

Subtilisin QK, which is newly identified as a fibrinolytic enzyme from Bacillus subtilis QK02, has the ability of preventing nitrotyrosine formation in bovine serum albumin induced by nitrite, hydrogen peroxide and hemoglobin in vitro verified by ELISA, Western-blot and spectrophotometer assay. Subtilisin QK also attenuates the fluorescence emission spectra of bovine serum albumin in the course of oxidation caused by nitrite, hydrogen peroxide and hemoglobin. Furthermore, subtilisin QK could suppress the transformation of oxy-hemoglobin to met-hemoglobin caused by sodium nitrite, but not the heat-treated subtilisn QK. Compared with some other fibrinolytic enzymes and inactivated subtilisin QK treated by phenylmethylsulfonylfluoride, the ability of inhibiting met-hemoglobin formation of subtilisin QK reveals that the anti-oxidative ability of subtilisin QK is not concerned with its fibrinolytic function. Additionally, nitrotyrosine formation in proteins from brain, heart, liver, kidney, and muscle of mice that is intramuscular injected the mixture of nitrite, hydrogen peroxide and hemoglobin is attenuated by subtilisin QK. Subtilisin QK can also protect Human umbilical vein endothelial cell (ECV-304) from the damage caused by nitrite and hydrogen peroxide.

• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.9_10 s.146
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• pp.1295-1305
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• 2005

The study was based on a three-stage, non-repetitive factorial experiment in which chemical-rotted kenaf fibers were treated separately with hydrogen peroxide concentrations of $0.5\%,\;1\%\;and\;2\%$, with pH solutions of 7, 9 and 11, and treatment times of 30, 60 and 90 minutes. Under optimal conditions, the study was conducted to determine the bleaching efficiency by the addition of chelators, penetrants and surfactants. The bleaching effects on the kenaf fibers were high in high hydrogen peroxide concentration, high in alkali solution pH, low in long treatment time. The optimal level of hydrogen peroxide on bleaching effects were at $2\%$ hydrogen peroxide concentration, with pH of 11 and treatment time of 60 minutes. Under the conditions of $2\%$ hydrogen peroxide concentration, pH 11 and treatment time of 60 minutes, the addition of chelator: Sodim Pyrophosphate(SP), Citric Acid(CA) made the bleaching effects of the kenaf fibers high.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.04b
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• pp.375-380
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• 1999

In order to improve the optical properties of high yield pulp, bleached chemi-thermo-mechanical pulp (BCTMP) was produced from CTMP of Betula maximowicziana Regel by two staged ozone-hydrogen peroxide bleaching. This pulp was used for the evaluation of the improvement of optical properties, chemical characteristics of lignin in fiber, and the relationship between lignin and optical properties in fiber cell wall. By hydrogen peroxide treatment, the brightness was improved, but the post color number (PC No.) was not. There was little improvement on optical properties by ozone treatment, but his could be solved by using two staged ozone-hydrogen peroxide bleaching. The hydrogen peroxide treatment did not make nay change on chemical characteristics of lignin in cell wall, but by ozone treatment, it was found that the non-aromatic conjugated structure was existed in the surface of cell wall, but this could be removed by hydrogen peroxide treatment in two staged ozone-hydrogen peroxide treatment. Therefore, the optical properties was significantly improved due to the removal of non-aromatic conjugated structure.

• Journal of Nutrition and Health
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• v.32 no.3
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• pp.318-326
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• 1999

Apoptotic cell death, characterized by DNA fragmentation and morphological changes, has previously been shown to occur in vascular endothelial cells cultured with hydrogen peroxide. The present study examined the induction of apoptosis by hydrogen peroxide and whether pyruvate, a key glycolytic intermediate and $\alpha$-keto-monocarboxylate, can inhibit the apoptotic effects in bovine pulmonary artery endothelial cells(BPAECs). Culture with 500uM hydrogen peroxide resulted in 30% cell death and induced morphological changes and DNA fragmentation. Cell injury was inhibited by the treatment with pyruvate. Pyruvate(0.1-5.0mM), and cell viability increased in a dose-dependent manner. In the presence of pyruvate(10~20mM), the viability was improved to over 95%. In contrast, treatment with lactate, a reduced form of phyuvate, did not protect against cell death oxidative stress-induced loss of viability and apoptosis was examined with $\alpha$-cyano-3-hydroxycinnarmate(COHC) as a selective mitochondrial monocarboxylate transport blocker. Incubation with COHC(500uM) did not significantly affect cell viability in the presence of hydrogen peroxide. The cytoprotection by pyruvate(3mM)against hydrogen peroxide stress was abolished by COHC. This indicates that the cytoprotection by pyruvate against oxidative stress in endothelial cells is mediated, at least in part, by mitochondrial pyruvate uptake and hence endothelial enerygetics. However, cytosolic mechanisms related, at least in part, by mitochondrial pyruvate uptake and hence endothelial energetics. However, cytosolic mechanisms related to the glutathione system may also contribute. The results suggest that pyruvate has therapeutic potential in the treatment of oxidative stress-induced cytotoxicity associated with increased apoptosis.

• Journal of Korean Society of Water and Wastewater
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• v.23 no.4
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• pp.491-497
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• 2009

The purpose of this study is to propose a method of controlling redtide microbes which grow abundantly and form harmful algal bloom in eutrophic waterbody with yellow loess and hydrogen peroxide. In the laboratory test, hydrogen peroxide was applied to single species of C. polykrikoides and multispecies of redtide microbes. The seawater was evaluated by the pre-test analysis including chlorophyll-a, luminance and transmittance. The test results showed that both single and mixed species of redtide microbes could be controlled with the dose of 30mg $H_2O_2/L$. Residual hydrogen peroxide was completely decomposed with the addition of powdered yellow loess at 2g/L~10g/L. However, the decomposition rate of residual hydrogen peroxide for sintered granular yellow loess was relatively low compared to the use of powdered one. With the addition of dissolved oxygen concentration was increased at a rate of 0.013 mg DO/mg $H_2O_2$, which is a little lower than the one predicted theoretically. No evidence for any detrimental effects on Artemia, a type of brine shrimps, was shown up to the concentration of 100mg $H_2O_2/L$.