• Title, Summary, Keyword: hydrogen peroxide

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Degradation of residual pharmaceuticals in water by UV/H2O2 advanced oxidation process (UV/H2O2 고도산화기술을 이용한 수중 잔류의약물질 제거)

  • Park, Chinyoung;Seo, Sangwon;Cho, Ikhwan;Jun, Yongsung;Ha, Hyunsup;Hwang, Tae-Mun
    • Journal of Korean Society of Water and Wastewater
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    • v.33 no.6
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    • pp.469-480
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    • 2019
  • This study was conducted to evaluate the degradation and mineralization of PPCPs (Pharmaceuticals and Personal Care Products) using a CBD(Collimated Beam Device) of UV/H2O2 advanced oxidation process. The decomposition rate of each substance was regarded as the first reaction rate to the ultraviolet irradiation dose. The decomposition rate constants for PPCPs were determined by the concentration of hydrogen peroxide and ultraviolet irradiation intensity. If the decomposition rate constant is large, the PPCPs concentration decreases rapidly. According to the decomposition rate constant, chlortetracycline and sulfamethoxazole are expected to be sufficiently removed by UV irradiation only without the addition of hydrogen peroxide. In the case of carbamazepine, however, very high UV dose was required in the absence of hydrogen peroxide. Other PPCPs required an appropriate concentration of hydrogen peroxide and ultraviolet irradiation intensity. The UV dose required to remove 90% of each PPCPs using the degradation rate constant can be calculated according to the concentration of hydrogen peroxide in each sample. Using this reaction rate, the optimum UV dose and hydrogen peroxide concentration for achieving the target removal rate can be obtained by the target PPCPs and water properties. It can be a necessary data to establish design and operating conditions such as UV lamp type, quantity and hydrogen peroxide concentration depending on the residence time for the most economical operation.

Treatment of High Strength para-Nitrophenol using Fenton-like Oxidation Catalyzed by Steeler's Dust (제강분진을 촉매로 활용한 펜톤유사산화에 의한 고농도 para-Nitrophenol의 처리)

  • 배범한;정재훈;이성재;장윤영;박규홍;장윤석
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • pp.136-139
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    • 2000
  • Fenton-like oxidation of para-nitrophenol(PNP) was studied using hydrogen peroxide iii combination with steeler's dust substituted for ferrous iron in Fenton's reaction. Various factors critical in the degradation of PNP were studied, including hydrogen peroxide dosage, concentration of steeler's dust. and initial pH. Experimental results showed that 1,000mg/L PNP and its oxidation intermediate could be mostly decomposed within 30m1n by 10g/L steeler's dust, 0.25% hydrogen peroxide, and initila pH of 3.0. The reaction rate constant (k) of CODcr concentration were calculated with the addition of steeler's dust(0.0059 min$^{-1}$ (g/L)$^{-1}$ ) and hydrogen peroxide(0.2965 min$^{-1}$ (%)$^{-1}$ ), respectively.

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Development of a Hydrogen-Peroxide Rocket Engine of l00N Thrust (l00N $H_2O_2$ Monopropellant 로켓 엔진의 개발)

  • Sang-Hee Ahn;S. Krishnan;Choog-Won Lee
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • pp.131-134
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    • 2003
  • There has been a renewed interest in the use of hydrogen peroxide as an oxidizer in bipropellant liquid rocket engines as well as in hybrid rocket engines. This is because hydrogen peroxide is a propellant of low toxicity and enhanced versatility. The present paper details the features of the designed engine of l00N thrust and its facility. Also explained is the arrangement of the distillation unit to be used to prepare rocket-grade hydrogen-peroxide propellant. Results of the simulated "cold" tests are presented.

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Low-temperature Dyeing of Silk Fabrics using a Glyoxal/Hydrogen peroxide Redox System (Glyoxal/Hydrogen peroxide-Redox System을 사용한 견직물의 저온염색)

  • 이내연;백두현;임종열;임영훈
    • Textile Coloration and Finishing
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    • v.6 no.1
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    • pp.1-7
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    • 1994
  • A low-temperature dyeing system for silk fabrics based on a redox system has been investigated. Some factors affecting dyeing of silk fabrics with levelling acid dyes in the absence and presence of certain redox system were investigated under different conditions. The variables studied were; type and concentration of redox system, dyeing conditions, i. e. temperature and time, dye concentration, material-to-liquor ration(LR) and colour fastness. The colour strength(K/S value) is outstandingly higher in the presence than in the absence of redox system. A comparison between the colour strength values of such dyeings abtained the three redox system would call for the following order ; Glyoxal/hydrogen peroxide>thiourea/hydrogen peroxide>glucose/hydrgen peroxide> nothing. In the presence of redox system, free radicals are supposed to be formed in both the fiber and the dye and the interaction between these free radicals bring about covalent fixation beside the usual electrostatic bonds, hydrogen bonds and Van der Waals forces.

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Ignition Studies Of Igniter using Hydrogen Peroxide And Kerosene (Catalyst Ignition) (과산화수소/케로신(촉매점화) 점화기의 점화특성에 관한 연구)

  • Kim, Ki-Woo;Kim, Tae-Wan;Lee, Yang-Suk;Kim, Yoo;Ko, Young-Sung;Kim, Sun-Jin
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • pp.57-60
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    • 2009
  • Exothermic and ignition characteristic of igniter is very important factor in engine performance. Since the igniter performance is effected by Hydrogen Peroxide decomposition rate, we have to test the preliminary catalyst performance test. In this report, after making igniter using hydrogen peroxide/kerosene, a thermal characteristic were examined by comparing hydrogen peroxide mass and catalyst mass. And then we study ignition characteristic of the affects of O/F ratio using the previous data.

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Development of Hydrogen Peroxide Thruster adopted Silver Catalyst (은을 촉매로 사용하는 과산화수소 추력기 개발)

  • Lee, Su-Lim;Lee, Choong-Won
    • Journal of the Korean Society of Propulsion Engineers
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    • v.11 no.4
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    • pp.67-73
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    • 2007
  • In recent years hydrogen peroxide has become considerably more attractive as a green rocket propellant so a laboratory model of hydrogen peroxide thruster adopted silver catalyst and a test facility has been developed to research a hydrogen peroxide propulsion. The design scheme of thruster and the test data are presented including ignition delay, efficiency of characteristic exhaust velocity. As a result, 95% of efficiency of characteristic exhaust velocity was obtained at steady state operation condition.

Biodegradation of Hydrogen Peroxide in Semiconductor Industrial Wastewater with Catalase from Micrococcus sp.

  • Oh, Sung-Hoon;Yu, Hee-Jong;Kim, Moo-Sung;So, Sung;Suh, Hyung-Joo
    • Preventive Nutrition and Food Science
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    • v.7 no.1
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    • pp.33-36
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    • 2002
  • A catalase from Micrococcus sp. isolated from soil was applied to degrade hydrogen Peroxide in wastewater from a semiconductor industry. The degradation rates of hydrogen peroxide increased with increasing reaction time and catalase concentrations in the reaction mixture. However, in the presence of aluminum chloride or chloride oxide used in detergent compounds, the degradation rate of hydrogen peroxide was not affected. Enzyme stabilizers and antifoam did not affect the degradation rates of hydrogen peroxide.

Oxidation of Pyridazinyl Sulfides: Synthesis of New Pyridazinyl Sulfoxides and Pyridazinyl Sulfones with Aqueous Hydrogen Peroxide (Pyridazinyl Sulfides의 산화반응: 과산화수소를 이용한 새로운 Pyridazinyl Sulfoxides 및 Pyridazinyl Sulfones의 합성)

  • Park, Eun-Hee;Park, Myung-Sook
    • YAKHAK HOEJI
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    • v.56 no.6
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    • pp.390-394
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    • 2012
  • A series of new pyridazinyl sulfoxides 3a~e and pyridazinyl sulfones 4a were synthesized for development of candidates to retain anticancer activity. The utility of sulfoxides and sulfones in both laboratory and industrial practice was quickly recognized, and these species have been extensively utilized, including as pharmaceutical intermediates and anticancer agents. Alkylthiopyridazines 2a~e were prepared from the 3,6-dichloropyridazine using allylthiolation with alkyl mercaptan. Sulfides could be oxidized to sulfoxides or sulfones using 1~3 equivalents of hydrogen peroxide as an oxidant. The oxidation of sulfoxides to sulfones was also accomplished with aqueous hydrogen peroxide. Formation of 3a~e and 4a was undertaken with stirring using 35% hydrogen peroxide at room temperature in acetic acid for 18~72 h. Synthetic compounds were identified using NMR spectrum.

Kinetics and Mechanism of Reaction of Hydrogen Peroxide with Copper(Ⅱ)-Schiff Base Complexes (구리(Ⅱ)-시프염기 착물과 과산화수소의 반응속도 및 메카니즘)

  • Kim, Sun-Deuk;Joung, Mu-Su;Jin, Gyoung-Rok;Kim, Chang-Su
    • Journal of the Korean Chemical Society
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    • v.39 no.12
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    • pp.932-939
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    • 1995
  • Rates of the decomposition of hydrogen peroxide by copper(Ⅱ)-Schiff base complexes were measured at various concentrations of hydrogen peroxide. Decomposition rates of hydrogen peroxide increased with increasing pH for CuⅡBSDT and CuⅡBSTP but then decreased with the same variation of the pH for CuⅡBSTT. A possible mechanism in accord with experimental results was proposed. The mechanism involves the deprotonation of copper(Ⅱ)-Schiff base complexes of hydrogen peroxide, followed by the formation of peroxo complexes at the rate-determining step.

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Liquid Crystal Droplet Patterns to Monitor Catalase Activity at Femtomolar Levels

  • Yoon, Stephanie;Jang, Chang-Hyun
    • Bulletin of the Korean Chemical Society
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    • v.35 no.9
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    • pp.2704-2710
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    • 2014
  • Catalase (CAT) decomposes hydrogen peroxide that is toxic to the body. In this study, simple and sensitive detector has been developed for observing catalase activity using liquid crystal droplet system. Microscale LC droplet patterns are formed by spreading aldehyde-doped nematic liquid crystal on pre-treated glass slides. When hydrogen peroxide is added, aldehyde is oxidized and amphiphiles are formed. Dodecanoates cause the pattern to transit from bright to dark as they self-assemble to form a carboxyalte monolayer at the interface. When a drop of pre-incubated CAT and hydrogen peroxide mixture is placed onto the pattern, bright fan-shape is observed. This planar optical appearance indicates that catalase has decomposed hydrogen peroxide. Compared to the detectors that have been previously developed, this system is more sensitive with detection limit of 1fM. This research suggests further studies to be on LC droplet patterning to develop highly sensitive and methodologically simple sensors for various chemicals.