• 제목/요약/키워드: catalys

검색결과 4건 처리시간 0.017초

수소/산소/이산화탄소 혼합기의 백금촉매반응특성 : 비균일 반응의 점화 온도 (Heterogeneous Ignition of $H_2/O_2/CO_2$ Mixture Over Platinum Catalyst)

  • 남창호;신현동
    • 한국연소학회:학술대회논문집
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    • 한국연소학회 2001년도 제23회 KOSCO SYMPOSIUM 논문집
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    • pp.90-96
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    • 2001
  • Catalytic ignition of $H_2/O_2/CO_2$ mixtures over platinum catalyst is experimentally investigated by using microcalorimetry. For comparison, $N_2$ and Ar is also used as diluent gas. The gas mixture flows toward platinum foil heated by electric current at atmosphere pressure and ambient temperature. The ignition temperature range 350-445K according to the fuel ratio, dilution ratio and diluent gas. It increases as the fuel ratio and dilution ratio increase. $H_2/O_2$ mixture with $CO_2$ ignites at higher temperature than with other diluents by 30-50K. Several experimental evidences show the inhibition effects of $CO_2$ in $H_2-O_2$ heterogeneous reaction is considerable

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연료 개질기용 고성능 수성가스 전환반응 촉매 개발 (Development of High Performance WGS Catalyst for Fuel Processor Applications)

  • 이윤주;류종우;김대현;최은형;노원석;이상득;문동주
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2006년도 추계학술대회
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    • pp.451-454
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    • 2006
  • WGS reaction over Mo2C and ceria based catalysts was investigated to develop an alternative commercial Cu-Zn/Al2O3 catalyst for fuel processor and hydrogen station. The Mo2C catalysts were prepared by a temperature programmed method and the various metal supported cerium oxide catalysts were prepared by an Impregnation method. The catalysts were characterized by the N2 physisorption, Co chemisorption, XRD, TEM and TPR. It was found that Mo2C and 0.2wt% Pt-40wt%, Ni/CeO2 catalysts had higher activity and stability than the Cu-Zn/Al203 above $260^{\circ}C$. Moreover, CO conversion of more than 85% was observed at $280{\sim}300^{\circ}C$. But all catalysts were deactivated during the thermal cycling runs. The results suggest that these catalysts are an attractive candidate for the alternative Cu-Zn/Al2O3 catalyst for fuel processor and hydrogen station applications.

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알칼리용액에서 산소환원 및 발생반응에 대한 La0.8Sr0.2CoO3 전극의 기체확산층 영향 (Effect of Gas Diffusion Layer on La0.8Sr0.2CoO3 Bifunctional Electrode for Oxygen Reduction and Evolution Reactions in an Alkaline Solution)

  • 로페즈 카린;양진현;선호정;박경세;엄승욱;임형렬;이홍기;심중표
    • 한국수소및신에너지학회논문집
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    • 제27권6호
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    • pp.677-684
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    • 2016
  • Various commercially available gas diffusion layers (GDLs) from different manufacturers were used to prepare an air electrode using $La_{0.8}Sr_{0.2}CoO_3$ perovskite (LSCP) as the catalyst for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) in an alkaline solution. Various GDLs have different physical properties, such as porosity, conductivity, hydrophobicity, etc. The ORR and OER of the resulting cathode were electrochemically evaluated in an alkaline solution. The electrochemical properties of the resulting cathodes were slightly different when compared to the physical properties of GDLs. Pore structure and conductivity of GDLs had a prominent effect and their hydrophobicities had a minor effect on the electrochemical performances of cathodes for ORR and OER.

4급 암모늄염 촉매에 의한 Glycidyl Methacrylate와 이산화탄소의 부가반응 (Addition Reaction of Glycidyl Methacrylate with Carbon Dioxide Using Quaternary Ammonium Salts as Catalys)

  • 양정규;문정열;정성미;박대원;이진국
    • 공업화학
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    • 제7권6호
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    • pp.1156-1163
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    • 1996
  • 본 연구는 이산화탄소와 glycidyl methacrylate(GMA)의 부가반응에 의한(2-oxo-1,3-dioxolane-4-yl)methacrylate(DOMA)의 합성에 4급 암모늄염 촉매의 특성을 고찰한 것이다. 4급 암모늄염 상이동 촉매의 알킬기의 크기가 크고 짝음이온의 친핵성이 강할수록 촉매활성이 높았다. 폴리에틸렌글리콜이나 NaI, 18-crown-6를 단독으로 사용한 경우에는 반응활성이 전혀 없었으나 NaI와 18-crown-6의 혼합물을 촉매로 사용한 결과 비교적 좋은 DOMA 수율을 얻었다. 또한 극성이 낮은용매를 사용한 경우에는 단량체 형태의 DOMA를 얻을 수 있었고, 극성이 높은 비양성자성 용매를 사용한 결과 DOMA의 고분자를 직접 합성할 수 있었다. 한편 고압 회분반응기에서 이산화탄소의 압력변화를 통한 속도론 적 고찰 결과 반응속도는 GMA와 이산화탄소의 농도에 대하여 각각 1차 반응이었고, 이때 반응속도 상수 k는 0.56L/mol hr이었으며 diglyme 용매에 대한 $80^{\circ}C$에서 $CO_2$의 Henry 상수 H'는 $6.5{\times}10^{-4}mol/L{\cdot}kPa$로 나타났다.

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