• Title/Summary/Keyword: Chemical oxidation

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The Effect of Iron Catalysts on the Formation of Alcohol and Ketone in the Biomimetic Oxidation of Cyclohexane

  • Kim Seong-Bo;Lee Kyu-Wan;Kim, Yong-Joon;Hong Seog-In
    • Bulletin of the Korean Chemical Society
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    • v.15 no.6
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    • pp.424-427
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    • 1994
  • Effects of iron compounds in known biomimetic oxidation systems (Gif IV and GoAgg II) have been studied on activity and ketone/alcohol selectivity of cyclohexane oxidation. Both ketone/alcohol ratio and cyclohexane conversion were affected by counter-ion Z of iron compounds Z-Fe. When Z has a more electron withdrawing property, the reactivity is increased and the formation of ketone is favored. From these experimental results, a new mechanism is proposed for the biomimetic oxidation system.

Palladium Dichloro Complex Catalysed Oxidation of Cyclopentene by Dioxygen in Tetralin$^\dag$

  • Takehira, Katsuomi;Hayakawa, Takashi;Orita, Hideo;Shimizu, Masao;Oh, In-Hwan
    • Bulletin of the Korean Chemical Society
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    • v.8 no.4
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    • pp.254-257
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    • 1987
  • Palladium dichloro complexes catalysed the oxidation of cyclopentene by dioxygen in tetralin solvent at ambient temperature. Cyclopentanone formed mainly together with autoxidation products from both cyclopentene and tetralin. The oxidation seems to proceed by co-oxidation mechanism, where tetralin was first oxidized to its hydroperoxide which then oxidized cyclopentene to cyclopentanone. Mechanism of the other by-products formations has been discussed.

Comparison of Land Farming and Chemical Oxidation based on Environmental Footprint Analysis (환경적 footprint 분석을 통한 토양경작법과 화학적산화법의 비교)

  • Kim, Yun-Soo;Lim, Hyung-Suk;Park, Jae-Woo
    • Journal of Soil and Groundwater Environment
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    • v.20 no.3
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    • pp.7-14
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    • 2015
  • In this study, land farming and chemical oxidation of a diesel-contaminated site is compared to evaluate the environmental impact during soil remediation using the Spreadsheet for Environmental Footprint Analysis by U.S. EPA. Each remediation process is divided into four phases, consisting of soil excavation, backfill and transportation (Phase 0), construction of remediation facility (Phase 1), remediation operation (Phase 2), and restoration of site and waste disposal (Phase 3). Environmental footprints, such as material use, energy consumption, air emission, water use and waste generation, are analyzed to find the way to minimize the environmental impact. In material use and waste generation, land farming has more environmental effect than chemical oxidation due to the concrete and backfill material used to construct land farming facility in Phase 1. Also, in energy use, land farming use about six times more energy than chemical oxidation because of cement production and fuel use of heavy machinery, such as backhoe and truck. However, carbon dioxide, commonly considered as important factor of environmental impact due to global warming effect, is emitted more in chemical oxidation because of hydrogen peroxide production. Water use of chemical oxidation is also 2.1 times higher than land farming.

Electro-oxidation Kinetics of Cerium(III) in Nitric Acid Using Divided Electrochemical Cell for Application in the Mediated Electrochemical Oxidation of Phenol

  • Matheswaran, Manickam;Balaji, Subramanian;Chung, Sang-Joon;Moon, Il-Shik
    • Bulletin of the Korean Chemical Society
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    • v.28 no.8
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    • pp.1329-1334
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    • 2007
  • The electrochemical oxidation of cerium(III) was carried out using divided and undivided electrochemical cells in nitric acid medium. It was found that divided cell with Nafion 324 as the separator gave good conversion yield with high current efficiency compared to the undivided cell. The efficiency of the divided electrochemical cell was further optimized in terms of cell voltage, temperature, flow rate of solution recirculation, concentrations of Ce(III) and nitric acid. The better conditions for 1 M Ce(III) in 3 M nitric acid were found to be 2.5 V, 363 K and 100 mL/min recirculation flow rate based on the current efficiency under the experimental conditions investigated. The Ce(IV) oxidant produced was used as a mediator for the mineralization of phenol. The mineralization efficiency of the cerium mediated electrochemical oxidation was found rapid and higher compared to the direct electrochemical oxidation based on CO2 evolution under the same conditions.

Mechanism of Intercalation Compounds in Graphite with Hydrogen Sulfate (I. Study of Intermediate Phase between 2 Stage and 1 Stage in Graphite Hydrogen Sulfate with Anodic Oxidation) (흑연에 황산을 Intercalation 시킬때의 Mechanism 규명 (I. 전기적 산화방법에 의한 Graphite Salts의 중간상에 관한 연구))

  • 고영신;한경석;이풍헌
    • Journal of the Korean Ceramic Society
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    • v.22 no.6
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    • pp.5-8
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    • 1985
  • Graphite has been oxidized to graphite hydrogen sulfate in concentrated $H_2SO_4$. Anodic oxidation and chemical oxidation of graphite in $H_2SO_4$ generally leads to the formation of intercalation compounds of the ionic salt type through incorporation of $H_2SO_4^-$ions and $H_2SO_4$ molecules into the graphite. Several other reactions also accur at various points of the charging cycle. But there is no satisfactory kinetics and mechanism of intercalationin graphite. We have studied them with anodic oxidation and chemical oxidation. We found six distinct phenomena between 2nd stage and 1st stage in chemical oxidation. We examined them in detail by the following in the measurements electrical oxidation. X-ray diffractions UV-Vis spectroscopy density measurements. We could obtained a equation for kinetic according to the reaction rate from this results and mechanism of intercalation between 2nd stage and 1st stage with hydrogen sulfate in graphite. Three thesis were written for the mechanism of intercalation compounds in graphite with hydrogen sulfate ; first thesis is anodic oxidation second thesis is chemical oxidation and definition of transit phase between 2nd etc the third thesis is the kinetic mechanism of intercalation compounds in graphite with Hydrogen sulfate. This thesis is the first paper among three thesis as anodic oxidation.

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Synthesis of Cyclitol Derivatives (Ⅲ). Electrolytic Oxidation of myo-Inositol (Cyclitol 유도체 합성에 관한 연구 (제3보)-myo-Inositol의 전해 산화-)

  • Joo Hwan Sohn;Chong Woo Nam;Yu Ok Kim
    • Journal of the Korean Chemical Society
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    • v.15 no.3
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    • pp.127-132
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    • 1971
  • To obtain the various kinds of inosose stereomers, the process of electrochemical oxidation is more effective than chemical oxidation of myo-inositol. So that myo-inositol aqueous solution was electrolyzed by platinum and lead peroxide anode to confirming the occurrence of electrochemical oxidation. The result is that myo-inosose-2 is producing with high yield comparatively by electrolytic oxidation of myo-inositol. Also we studied about the relation between the electrolytic current efficiency and electrolytic temperature and anodic current density. The current efficiency is rising with lowering of electrolytic temperature identically in both anode such as platinum and lead peroxide and also rising with increasing of anodic current density in platinum anode, but inversely in lead peroxide.

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Oxidation of Ethylbenzene Using Nickel Oxide Supported Metal Organic Framework Catalyst

  • Peng, Mei Mei;Jeon, Ung Jin;Ganesh, Mani;Aziz, Abidov;Vinodh, Rajangam;Palanichamy, Muthiahpillai;Jang, Hyun Tae
    • Bulletin of the Korean Chemical Society
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    • v.35 no.11
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    • pp.3213-3218
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    • 2014
  • A metal organic framework-supported Nickel nanoparticle (Ni-MOF-5) was successfully synthesized using a simple impregnation method. The obtained solid acid catalyst was characterized by Powder X-ray diffraction (XRD), scanning electron microscopy (SEM), nitrogen adsorption-desorption and thermogravimetric analysis (TGA). The catalyst was highly crystalline with good thermodynamic stability (up to $400^{\circ}C$) and high surface area ($699m^2g^{-1}$). The catalyst was studied for the oxidation of ethyl benzene, and the results were monitored via gas chromatography (GC) and found that the Ni-MOF-5 catalyst was highly effective for ethyl benzene oxidation. The conversion of ethyl benzene and the selectivity for acetophenone were 55.3% and 90.2%, respectively.