• Title/Summary/Keyword: supported catalyst

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The Effects of Agglomeration of Catalyst on its Activity in Partial Oxidation Reforming (부분산화개질 반응에서 촉매의 응집이 촉매 활성에 미치는 영향)

  • Lee, Sang-Ho;Yoon, Sang-Ho;Jeon, Seung-Hyun;Bae, Jong-Myeon
    • 한국신재생에너지학회:학술대회논문집
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    • 2009.11a
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    • pp.203-206
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    • 2009
  • Agglomeration of catalysts is known as one of the major degradation mechanisms. Reforming of liquid fuel, which requires high temperature over $800^{\circ}C$, accelerates agglomeration of catalysts. In this work, The effects of agglomeration on catalysts activity in partial oxidation reforming conditions were investigated. Metal supported catalysts(Pt-CGO, Ru-CGO) were compared to perovskite-structured catalysts(NECS-P1, NECS-P2). High thermal stability of perovskite-structured catalysts was reported. Micro-reactor installed in electric furnace was used. its Temperature was raised from $800^{\circ}C$ to $1000^{\circ}C$ to accelerate agglomeration effect. To measure rate of agglomeration, BET analysis and CO pulse chemisorption were conducted on catalysts exposed to $1100^{\circ}C$. Metal supported catalysts showed degradation at $1000^{\circ}C$ and The rates were different according to metal supported. On the other hand perovskite-structured catalysts showed no degradation at $1000^{\circ}C$.

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Conversion of Vegetable Oils and Mixed Fat into Biodiesel Using $Al_2O_3$-Supported CaO Catalyst ($Al_2O_3$ 지지 CaO촉매에 의한 식물유와 혼합지방의 바이오디젤화)

  • Hyun, Young-Jin
    • Journal of the Korean Applied Science and Technology
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    • v.27 no.4
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    • pp.421-426
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    • 2010
  • The transesterification of rapeseed oil, soybean oil, and mixed fat were conducted at $65^{\circ}C$ with $Al_2O_3$-supported CaO, 0.8 wt% KOH, 1 wt% NaOH and mixed catalyst. The overall conversion(%) of rapeseed oil indicated to be 96% at the 12:1 molar ratio of methanol to oil, 8 wt% CaO and 2 wt% water. The pH ranges of biodiesel for mixed fat using four catalysts and for three fats using 8wt% CaO were 7.3-9.1, 7.3-7.5, respectively. The volumes of water needed to wash biodiesel from rapeseed oil using 0.8 wt% KOH and 8 wt% CaO were 15 mL and 3 mL.

Styrene Epoxidation over Cobalt Cyclam Immobilized SBA-15 Catalyst

  • Sujandi;Prasetyanto, Eko Adi;Han, Sang-Cheol;Park, Sang-Eon
    • Bulletin of the Korean Chemical Society
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    • v.27 no.9
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    • pp.1381-1385
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    • 2006
  • Cobalt (cyclam) complex has been successfully immobilized onto SBA-15, and proven to be an active catalyst for the epoxidation of styrene with tert-butyl hydroperoxide as a terminal oxidant. The selectivity for styrene oxide was observed to be up to 66% with 40% styrene conversion after 12h reaction time. The reversible redox cycle between Co(III) and Co(II) couple which was supposed to play key role during the epoxidation reaction was supported by a cyclic voltametry analysis. The textural properties of the catalyst was characterized by XRD, N2 adsorption-desorption, and TEM analysis.

The Characteristic of Prepared Electrode Catalyst and MEA using CNF and CNT (CNT 및 CNF를 이용하여 제조된 전극 촉매 및 막 전극 접합체의 특성)

  • 임재욱;최대규;류호진
    • Journal of the Microelectronics and Packaging Society
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    • v.11 no.1
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    • pp.59-64
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    • 2004
  • The performance of fuel cell electrode depends on the characteristics of the catalyst support material. This paper deals with the use of CNF(carbon nanofibre) and CNT(carbon nanotube) as platinum catalyst support. The CNF and CNT were synthesized with catalyst treated by mechanochemical process and were prepared by chemical vapor deposition (CVD) method. The platinum supported on CNF and CNT for polymer electrolyte membrane fuel cell (PEMFC) application. In result, the best I-V characteristic was verified by the prepared MEA(membrane electrode assembly) from twisted CNF that had a diameter of 65 nm.

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Synthesis of High Purity Carbon Nano Fibers and Hydrogen from Propane Decomposition

  • Hussain, S.Tajammul;Gul, Sheraz;Mazhar, M.;Larachi, Faical
    • Bulletin of the Korean Chemical Society
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    • v.29 no.2
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    • pp.389-392
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    • 2008
  • High purity carbon nano fibers/tubes (CNF/Ts) which contain 97% pure graphitic carbon are prepared by a new catalytic method. These carbon nano fibers/tubes are ready to use without any further purification. The striking feature of this method is the production of carbon nano fibers/tubes of narrow distribution range. The developed catalytic method also produces pure hydrogen. An additional advantage of this catalytic method is that catalyst can be reused without reactivation. Ni:Cu catalyst system is embodied into SCHOTT-DURAN filter disc of large pore size (40-100 mm). Due to the production of hydrogen in the reaction catalyst stability is enhanced and deactivation process is considerably slowed down.

Hydrogen Generation from $NaBH_4$ Hydrolysis on Co-Ni-P-B/Ni Foam Catalyst (Co-Ni-P-B/Ni foam 촉매에서 $NaBH_4$ 가수분해를 통한 수소 발생)

  • Park, Da-Ill;Kim, Tae-Gyu
    • Journal of Hydrogen and New Energy
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    • v.21 no.5
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    • pp.383-389
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    • 2010
  • Co-B, Co-P-B, Co-Ni-B and Co-Ni-P-B catalysts supported on Ni foam were prepared using electroless plating in the present study. The surface morphology of the catalysts/Ni foam was observed using SEM and EDS analysis. The Co-Ni-P-B/Ni foam catalyst showed the superior performance on hydrogen generation due to the uniform formation of catalyst particles on the Ni foam surface. The characteristics of hydrogen generation with Co-Ni-P-B/Ni foam catalyst was investigated at the variety of $NaBH_4$ and NaOH concentrations. Durability test was performed, resulting in the stable hydrogen generation for 6 hours.

An important factor for the water gas shift reaction activity of Cu-loaded cubic Ce0.8Zr0.2O2 catalysts

  • Jang, Won-Jun;Roh, Hyun-Seog;Jeong, Dae-Woon
    • Environmental Engineering Research
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    • v.23 no.3
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    • pp.339-344
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    • 2018
  • The Cu loading of a cubic $Ce_{0.8}Zr_{0.2}O_2$-supported Cu catalyst was optimized for a single-stage water gas shift (WGS) reaction. The catalyst was prepared by a co-precipitation method, and the WGS reaction was performed at a gas hourly space velocity of $150,494h^{-1}$. The results revealed that an 80 wt% $Cu-Ce_{0.8}Zr_{0.2}O_2$ catalyst exhibits excellent catalytic performance and 100% $CO_2$ selectivity ($X_{CO}=27%$ at $240^{\circ}C$ for 100 h). The high activity of 80 wt% $Cu-Ce_{0.8}Zr_{0.2}O_2$ catalyst is attributed to the presence of abundant surface Cu atoms and the low activation energy of the resultant process.