• 제목/요약/키워드: Electrochemical oxidation

검색결과 685건 처리시간 0.027초

Indirect Electrochemical Oxidation of Phenol by Ce4+, Controlling Surface Insulation of Au Electrode

  • Pyo, Myoung-Ho;Moon, Il-Shik
    • Bulletin of the Korean Chemical Society
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    • 제26권6호
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    • pp.899-902
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    • 2005
  • Indirect electrochemical oxidation of phenol by $Ce^{4+}$ was investigated in sulfuric acid solutions. It was found that electrode fouling during oxidation of phenol can be controlled by adjusting the time interval (TI) of double potential steps (DPSs). While the electroactivity was greatly decreased after several DPSs of a relatively long TI, repeated DPSs with a short potential pulse showed substantial amounts of electroactivity after a few hundreds or thousands DPS, suggesting that the formation of an insulating layer can be controlled by adjusting a potential program. Effectiveness of the consecutive application of DPSs for phenol decomposition was confirmed by GC-MS.

용융탄산염형 연료전지 대체음극재료인 Co/Ni alloy의 용융염에서의 in situ oxidation/lithiation과 전기화학적인 거동 연구 (In Situ Oxidation/Lithiation and Electrochemical Behavior of CoNi Alloy as Alternative Material for Molten Carbonate Fuel Cell Cathodes)

  • 조은애;류보현;한종희;윤성필;남석우;임태훈;홍성안;김광범
    • 한국전기화학회:학술대회논문집
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    • 한국전기화학회 2002년도 추계총회 및 학술발표회
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    • pp.3-4
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    • 2002
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Electrochemical Oxidation of Benzidine and Hydrazobenzene

  • Won Mi-Sook;Shim Yoon-Bo;Park Su-Moon
    • Bulletin of the Korean Chemical Society
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    • 제13권6호
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    • pp.680-683
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    • 1992
  • The electrochemistry of benzidine and hydrazobenzene was studied in water-acetonitrile mixed solutions at various pHs and the results are reported. The cyclic voltammetric peak for the oxidation of benzidine shows a pH dependency of -62 mV/pH in the pH range of 0-3.5, no pH dependency between pH values of 3.5 and about 10.5, and of about -50 mV/pH between pH=10.50 and 14.0, indicating that oxidation mechanisms differ depending on the pH of the medium. However, the CV peak for the hydrazobenzene oxidation is shown to be independent of pH of the medium, suggesting that the proton is not involved in the rate limiting step of the electrochemical oxidation of hydrazobenzene to azobenzene. Results of in situ spectroelectrochemical experiments indicate that the oxidation products obtained during the oxidation of benzidine and hydrazobenzene depend on the result of dynamic equilibria taking place at various pHs.

전해산화에 의한 백금전극상 전도성 폴리아닐린 피막의 생장 거동(II) (Growth Behavial Couctive PolyanilineFilm on a Platinum Electrode by Electrochemical Oxidation (II))

  • 신성호;이주성
    • 한국표면공학회지
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    • 제21권3호
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    • pp.95-102
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    • 1988
  • The anodic oxidation of aniline in aqueous sulfuric acid solution on a platinum was studied. To examine of mechanism of this reaction, the date were obtained during controlled potential electrolysis, aided by computer system. The reaction mechanism was assumed the electrochemical-chemical-electrochemical(ECE) mechanism. We obtained the result that the intial charge transfer step proceeds through a radical cation, and this radical cation were bound cation led to may type of dimer in which p-aminodiphenylamine was de-electronated again to give the polymer.

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전기화학적 산화를 이용한 염료 처리에 중심합성설계와 반응표면분석법의 적용 (Application of the Central Composite Design and Response Surface Methodology to the Treatment of Dye Using Electrochemical Oxidation)

  • 김동석;박영식
    • 한국환경과학회지
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    • 제18권11호
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    • pp.1225-1234
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    • 2009
  • The aim of this research was to apply experimental design methodology in the optimization condition of electrochemical oxidation of Rhodamine B(RhB). The reactions of electrochemical oxidation were mathematically described as a function of parameters amounts of current, NaCl dosage, pH and time being modeled by the use of the central composite design, which was used for fitting quadratic response surface model. The application of response surface methodology using central composite design(CCD) technique yielded the following regression equation, which is an empirical relationship between the removal efficiency of RhB and test variable in actual variables: RhB removal (%) = 3.977 + 23.279$\cdot$Current + 49.124$\cdot$NaCI - 5.539$\cdot$pH - 8.863$\cdot$time - 22.710$\cdot$Current$\cdot$NaCl + 5.409$\cdot$Current$\cdot$time + 2.390$\cdot$NaCl$\cdot$time + 1.061$\cdot$pH$\cdot$time - $0.570{\cdot}time^2$. The model predicted also agree with the experimentally observed result($R^2$ = 91.9%).

Regulation of Electrochemical Oxidation of Glucose by lonic Strength-Controlled Virtual Area of Nanoporous Platinum Electrode

  • Kim, Jong-Won;Park, Se-Jin
    • 전기화학회지
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    • 제10권3호
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    • pp.203-206
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    • 2007
  • Electrochemical reaction of glucose was regulated by the electrochemically active area of nanoporous platinum, which is controlled by ionic strength. The profile of the oxidation current of glucose vs. ionic strength was identical with that of the electrochemically active area. This result confirms that the nanopores are virtually opened for the electrochemical reaction of glucose when the ionic strength climbs over a specific concentration and implies that the electrochemical reactions on nanoporous electrode surfaces can be controlled by concentration of electrolyte.

전기화학적 산화처리가 탄소섬유/극성화된 폴리프로필렌 복합재의 기계적 계면 특성에 미치는 영향 (Effects of Electrochemical Oxidation of Carbon Fibers on Mechanical Interfacial Properties of Carbon Fibers-reinforced Polarized-Polypropylene Matrix Composites)

  • 김현일;최웅기;오상엽;안계혁;김병주
    • 공업화학
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    • 제24권5호
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    • pp.476-482
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    • 2013
  • 본 연구에서는 탄소섬유 표면에 가해진 전기화학적 산화처리가 탄소섬유강화 극성화된 폴리프로필렌 기지 복합재료의 기계적 계면 물성에 미치는 영향을 알아보기 위해 전류밀도 변수에 따른 섬유표면의 변화를 관찰하였다. 표면처리 전후의 탄소섬유 표면특성은 주사전자현미경과 원자현미경, 적외선분광법, X선광전자분광법과 접촉각으로 분석하였다. 탄소섬유강화복합재의 기계적 계면특성은 임계응력세기인자를 측정하여 평가하였다. 실험 결과 전기화학적 산화처리 후 섬유 표면의 $O_{1s}$ 피크의 증가를 관찰할 수 있었고, 이는 섬유의 표면자유에너지의 증가를 유도하며, 탄소섬유와 폴리프로필렌의 계면 결합력이 증가된 것으로 판단된다. 결론적으로 탄소섬유강화복합재료의 기계적 물성은 탄소섬유와 극성 폴리프로필렌 기지와의 계면 강도조절을 통해 가능할 것으로 판단된다.

Electrochemical treatment of cefalexin with Sb-doped SnO2 anode: Anode characterization and parameter effects

  • Ayse, Kurt;Hande, Helvacıoglu;Taner, Yonar
    • Advances in nano research
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    • 제13권6호
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    • pp.513-525
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    • 2022
  • In this study, it was aimed to evaluate direct oxidation of aqueous solution containing cefalexin antibiotic with new generation Sn/Sb/Ni: 500/8/1 anode. The fact that there is no such a study on treatment of cefalexin with these new anode made this study unique. According to the operating parameters evaluation COD graphs showed clearer results compared to TOC and CLX and thus, it was it was chosen as major parameter. Furthermore, pseudo-first degree kd values were calculated from CLX results to show more accurate and specific results. Experimental results showed that after 60 min of electrochemical oxidation, complete removal of COD and TOC was accomplished with 750 mg L-1 KCl, at pH 7, 50 mA cm-2 current density and 1 cm anode-cathode distance. Also, the stability of the Sn/Sb/Ni anode was evaluated by taking SEM and AFM images and XRD analysis before and after of electrochemical oxidation processes. According to the results, it was not occurred too much change on the anode surface even after 300 h of electrolysis. Thus, it was thought that the anode material was not corroded to a large extent. Furthermore, the removal efficiencies were very high for almost all the time and conditions. According to the results of the study, electrochemical oxidation with new generation Sn/Sb/Ni anodes for the removal of cefalexin antibiotic was found very successful and applicable due to require less reaction time complete mineralization and doesn't require pH adjustment step compared to other studies in literature. In future studies, different antibiotic types should be studied with this anode and maybe with real wastewaters to test applicability of the process in treatment of pharmaceutical wastewaters containing antibiotics, in a better way.