• Title/Summary/Keyword: 촉매 층

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Oxidation Characteristics of Methanol on Pt/C and Pt-Ru/C Catalyst for the Anode of Direct Methanol Fuel Cell (Pt/C 및 Pt-Ru/C 촉매를 사용한 직접 메탄올 연료전지 연료극의 메탄올 산화 반응 특성)

  • 정두환;이창형;신동열
    • Journal of Energy Engineering
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    • v.7 no.1
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    • pp.35-43
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    • 1998
  • Electrodes using for the anode electrode of direct methanol fuel cell with Pt/C and Pt/Ru/C catalyst were prepared and characterized by SEM, TEM, thermal analysis and electrochemical analysis. The half cell tests were carried out with 1 M $H_2SO_4$ electrolyte and 1 M $CH_3OH$ in order to evaluate the electrode performance. The employed electrochemical methods were cyclic vol-tammetry and potentiodynamic polarization experiments. It was found that 20 w% polytetrafluoroethylene (PTFE) content in catalyst showed the best performance due to the best platinum utilization on PTFE-containing catalyst layer. It was found that Pt/Ru/C binary catalyst inhibited the poisoning of anode electrode showing improved performance compared to the Pt/C catalyst by the adsorption of oxygen containing species on the electrode surface at same time. The apparent activation energy for methanol oxidation on the Pt/Ru/C and Pt/C catalyst layer was 11.60 kJ/mol and 26.85 kJ/mol, respectively.

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Numerical Simulation of Catalyst Regeneration Process for Desulfurization Reactor (수치해석을 통한 탈황반응기용 촉매의 재생공정 분석)

  • Choi, Chang Yong;Kwon, Sang Gu;Liu, Jay;Im, Do Jin
    • Clean Technology
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    • v.23 no.2
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    • pp.140-147
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    • 2017
  • In this study, we performed numerical simulation for the catalyst regeneration process of diesel desulfurization reactor. We analyzed the changes in regeneration process according to purge gas flow rate, catalyst permeability, reactor size, and heat loss of reactor. We have found that the regeneration process is very much affected by temperature changes whereas it is hardly affected by catalyst permeability and porosity. We also estimated the regeneration time according to purge gas flow rate and initial temperatures and have found that increasing purge gas temperature is more effect for fast regeneration. The present results can be utilized to design a regeneration process of diesel desulfurization reactor for a fuel cell used in ships. Furthermore, the present work also can be used to design low sulfur diesel supply in oil refineries and therefore contribute to the development of clean petrochemical technology.

$DeNO_{x}$ Performance of Activated Carbon Catalysts Regenerated by Surfactant Solution (계면활성제 수용액에 의해 재생된 활성탄 촉매의 탈질 성능)

  • Park, Hye-Min;Park, Young-Kwon;Jeon, Jong-Ki
    • Korean Chemical Engineering Research
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    • v.49 no.6
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    • pp.739-744
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    • 2011
  • Activated carbon SCR(CSCR) catalyst that is used to remove $NO_x$ in exhaust gas including boron discharged from the production process of liquid crystal display(LCD) shows deactivation when boron is deposited to block the pores within the catalyst or to cover its active sites. The spent carbon catalyst is regenerated by washing with various surfactants, drying and calcination. For comparison of the physical and chemical properties before and after the regeneration with the variables, type of surfactants and calcination condition, element analysis by ICP, $N_{2}$ adsorption were conducted. $DeNO_{x}$ in SCR with $NH_3$ was carried out in a fixed bed reactor at $120^{\circ}C$. The activated carbon catalyst regenerated through washing with a non-ionic surfactant in $H_{2}O$ at $90^{\circ}C$ and calcination under $N_{2}$ gas at $550^{\circ}C$ shows similar level of surface area and $NO_x$ removal efficiency with those of fresh catalyst.

Activity and Characteristics of Cu-Mn Oxide Catalysts Supported on γ-Al2O3 (γ-Al2O3에 담지된 Cu-Mn 산화물 촉매의 활성 및 특성)

  • Kim, Hye-jin;Choi, Sung-Woo;Lee, Chang-Seop
    • Korean Chemical Engineering Research
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    • v.44 no.2
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    • pp.193-199
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    • 2006
  • The catalytic oxidation of toluene over $-Al_2O_3$ supported copper-manganese oxide catalysts in the temperature range of $160-280^{\circ}C$ was investigated by employing a fixed bed flow reactor. The catalysts were characterized by BET, scanning electron microscopy (SEM), temperature-programmed reduction(TPR), temperature-programmed oxidation(TPO), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction(XRD) techniques. Catalytic oxidation of toluene was achieved at the below $280^{\circ}C$, and the optimal content of copper and manganese in the catalyst was found to be 15.0 wt%Cu-10.0 wt%Mn. From the TPR/TPO and XPS results, the redox peak of 15 Cu-10 Mn catalyst shifted to the lower temperature, and the binding energy was shifted to the higher binding energy. Furthermore, It is considered that $Cu_{1.5}Mn_{1.5}O_4$ is superior to Mn oxides and CuO in the role as active factor of catalysts from the XRD results and also catalytic activities are dependent on the redox ability and high oxidation state of catalysts.

Deactivation and Regeneration of a Used De-NOx SCR Catalyst for Wastes Incinerator (소각로 SCR 폐탈질 촉매의 피독과 효율재생에 관한 연구)

  • Lee, Sang-Jin;Hong, Sung-Chang
    • Applied Chemistry for Engineering
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    • v.19 no.3
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    • pp.259-263
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    • 2008
  • The catalytic activity of the used catalyst, $V_2O_5/TiO_2$, for MSW incinerators was investigated focusing on its regeneration. As the result of the experimental analysis, the NOx removal efficiency difference between the fresh catalyst and used catalyst is about 60% at $260^{\circ}C$ and 1, 2-dichlorobenzen (1, 2-DCB) removal efficiency difference is about 14% at $200^{\circ}C$, in honeycomb test. And the catalysts, both the fresh and used, were characterized by XRD, TGA, and ICP techniques in order to investigate the deactivation. On the basis of the results, it is found that the used catalyst is deactivated by ammonium-sulfates, heavy metals (Pb, As etc.), alkali metals (Ca), and phase transfer of $TiO_2$. Also calcination treatment under nitrogen and air condition was excellent than washing and calcination treatment.

Polymer-Supported Crown Ethers (II). Efficiency for Phase Transfer Catalyst (고분자 물질로 지지된 크라운 에테르류(II) 상이동 촉매 효능)

  • Jae Hu Shim;Kwang Bo Chung;Seung Hyun Chang;Dae Kyung Song;Yong Kiel Sung
    • Journal of the Korean Chemical Society
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    • v.32 no.6
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    • pp.593-602
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    • 1988
  • Polymer-supported crown ethers (Ps-CE) which can be used for phase-transfer catalyst (PTC) were synthesized for the purpose of allowing reusable function to ordinary crown ethers, and the kinetics of the liquid-solid-liquid triphase-catalyzed nucleophilic displacement reaction of iodide (aqueous phase) on 1-bromooctane (organic phase) using synthesized Ps-CE (solid) were studied. Ps-CE were obtained by grafting of hydroxymethyl crown ethers to 1~2% cross-linked chloromethylated polystyrene. All reactions followed a pseudo-first order dependency on the 1-bromooctane concentration and the observed rate constants $(k_{obsd})$ were linearly related to the molar equivalents of Ps-CE, and were subjected to the influence of cross-linking density of polymer backbone, solvent and the reaction temperature. The catalytic activity of Ps-CE was also compared with that of structurally similar soluble crown ethers, and used Ps-CE were easily recovered after the reaction by simple filtration and could be reused without loss of catalytic activity in the same anionic displacement reaction. Enthalpies and entropies of activation associated with the displacement were 10~20kcal $mol^{-1}, 20~55eu. respectively, and the free energy of activation was ~30kcal mol^{-1}$.

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$NO_x$ Removal of Vanadium based Catalyst with Constituent Compositions (조성성분에 따른 바나듐계 촉매의 탈질특성)

  • Baek, Geun-Ho;You, Seung-Han;Kim, Sang-Wung;Park, Young-Ok;Cha, Wang-Seog
    • Proceedings of the KAIS Fall Conference
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    • 2010.11a
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    • pp.294-297
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    • 2010
  • 본 연구논문에서는 주요 대기 오염물질인 $NO_x$를 처리하기 위해 다양한 종류의 촉매를 사용하여 탈질 특성을 조사하였다. 여러 종류의 담체에 다양한 종류의 활성물질을 답지한 촉매를 사용하였으며, 고정층 반응기를 이용하여 반응온도, 공간속도, 수분함량 등과 같은 공정조건에 따른 탈질효율도 측정하였다. 전체적으로 담지된 활성물질이 증가할수록 탈질효율도 증가함을 알 수 있었다.

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Fabrication of electromagnetic shielding film used metal evaporated thin film for under coated layer (도금 하지층으로 금속 증착막을 이용한 전자파 차폐 필름의 제조)

  • Lee, Seong-Jun;Kim, Dong-Hyeon
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2013.05a
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    • pp.58-58
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    • 2013
  • 폴리에스테르 필름상에 무전해 Cu 도금 및 무전해 Ni-P 도금층을 형성하는 방법으로 박형 전자파 차폐 필름의 제조에 대하여 연구 하였다. 무전해 도금의 전처리 방법으로 기존의 Pd 촉매를 사용하는 대신에, 증착법에 의한 Sn 피막의 형성으로 전자파 차폐 특성 및 유연성이 우수한 박형 전자파 차폐 필름의 형성이 가능하게 되었다.

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핵융합연료 삼중수소 분리반응탑 전산모사

  • 정흥석;이한수;안도희;황재영;김상환;손순환;정양근;송명재;일본명
    • Proceedings of the Korean Nuclear Society Conference
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    • 1996.05c
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    • pp.453-457
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    • 1996
  • 월성원자력발전소에서 생성되는 삼중수소는 핵융합로의 필수원료물질이다. 삼중수소 분리반응 탑에 소요되는 다단탑의 단수와 최적운전온도 및 반응탑의 효율을 결정하기 위하여, 흡수층과 촉매층으로 구성된 분리반응탑을 모델링하고, 전산코드를 작성하였다. 이 전산코드의 결과는 실험치와 잘 일치하였으며, 최소반응단수를 갖는 설계온도는 8$0^{\circ}C$임이 밝혀졌다.

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MINI-MAP 물리층의 적합성 시험

  • 강윤근;이영준;권태상
    • ICROS
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    • v.2 no.4
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    • pp.63-71
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    • 1996
  • 산업화가 고도화 될수록 공장 또는 사무자동화의 필요성이 늘어날수록 정보공유의 필요성이 중요시되는데 이런 필요성들은 통신의 발전을 촉발시키는데 중요한 촉매가 되었다. 공장자동화에 사용되는 통신방법 중에 FULL-MAP, MINI-MAP, ETHERNET 등 여러가지가 있지만, 그 중 1993년 11월부터 1994년 3월까지 일본의 재단법인 기계진흥협회 기술연구소내의 MAP Test Center에서 실시했던 MIN-MAP의 물리층(Physical Layer)규격에 의한 적합성 시험을 받으면서 얻은 시험항목과 문제점 및 해결방안을 적기로 한다.

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