• 제목/요약/키워드: Gas phase reaction

검색결과 451건 처리시간 0.025초

고압 WGS 반응을 위한 Cu-ZnO/Al2O3 촉매상에서 기-액 계면 촉매 반응 특성 연구 (Catalytic Activity Tests in Gas-Liquid Interface over Cu-ZnO/Al2O3 Catalyst for High Pressure Water-Gas-Shift Reaction)

  • 김세훈;박노국;이태진
    • 한국수소및신에너지학회논문집
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    • 제22권6호
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    • pp.905-912
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    • 2011
  • In this study, the novel concept catalytic reactor was designed for water-gas shift reaction (WGS) under high pressure. The novel concept catalytic reactor was composed of an autoclave, the catalyst, and liquid water. Cu-ZnO/$Al_2O_3$ as the low temperature shift catalyst was used for WGS reaction. WGS in the novel concept catalytic reactor was carried out at the ranges of 150~$250^{\circ}C$ and 30~50 atm. The liquid water was filled at the bottom of the autoclave catalytic reactor and the catalyst of pellet type was located at the gas-liquid water interface. It was concluded that WGS reaction occurred over the surface of catalysts partially wetted with liquid water. The conversion of CO for WGS was also controlled with changing content of Cu and ZnO used as the catalytic active components. Meanwhile, the catalyst of honey comb type coated with Cu-ZnO/$Al_2O_3$ was used in order to increase the contact area between wet-surface of catalyst and the reactants of gas phase. It was confirmed from these experiments that $H_2$/CO ratio of the simulated coal gas increased from 0.5 to 0.8 by WGS at gas-liquid water interface over the wet surface of honey comb type catalyst at $250^{\circ}C$ and 50 atm.

기체 상태에서의 오존과 아황산가스의 반응연구 (The Kinetics Study of Ozone with Sulfur Dioxide in the Gas Phase)

  • 권영식
    • 대한화학회지
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    • 제35권2호
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    • pp.111-118
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    • 1991
  • 기체 상태의 오존(0.5 torr)과 이산화황간의 반응속도를 연구하였다. 이산화황은 7∼22 torr 의 압력범위에서 90∼155$^{\circ}$C의 온도영역에서 반응시켰다. 오존과 이산화황의 반응속도는 이산화탄소와의 반응보다 빨리 진행되었다. 오존과 이산화황의 반응속도식은 -d(O$_3 )/dt = k _0 (SO _2 )(M)(O _3)+2k _1(SO_2 )(O _3$)였다. 이 속도식의 첫 항은 3분자 반응으로 낮은 온도에서 우세하게 진행되었으며, 속도상수 k$_0 =(9.35{\pm}8.6){\times}10^9e^{-(11.05{\pm}2.04)kcal/RT}(M^{-2}s^{-1}$)이다. 속도식의 두번째 항은 2분자 열분해 반응으로부터 유도된 주된 반응으로 속도상수 k$_1=(1.53{\pm}1.5){\times}10^{11}e^{-22.7 kcal/RT}$이다. 전 반응차수는 주로 2차 반응이며 3차 반응과 복합반응으로 진행되었다.

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Al(OH)3-SiO2-AlF3계에서 기상-고상반응에 의한 뮬라이트 휘스커 합성 (Synthesis of Mullite Whiskers by Vapor-Solid Reaction in the System of Al(OH)3-SiO2-AlF3)

  • 이홍림;강종봉
    • 한국세라믹학회지
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    • 제43권6호
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    • pp.376-382
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    • 2006
  • In the $Al(OH)_3-SiO_2-AlF_3$ system, leaf-shaped fluorotopaz was first formed at $800^{\circ}C$ and mullite whisker was formed at $1,100^{\circ}C$. The mass transportation of Al and Si as gas phase, the fast reaction and growth, and the absence of liquid phase existence in mullite whisker showed that the formation and growth of mullite was from the solid-vapor reaction.

비 표면적 큰 코발트계 담지촉매를 사용한 피셔-트롭스 반응에 의한 탄화수소의 제조에 관한 연구 (A Study on the Synthesis of Hydrocarbon by Fisher-Tropsch Synthesis over Cobalt Catalysts with High Surface Area Support)

  • 김철웅;김유성;정순용;정광은;채호정;이관영
    • 한국응용과학기술학회지
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    • 제26권3호
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    • pp.279-287
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    • 2009
  • Fisher-Tropsch synthesis for the production of hydrocarbon from syngas was investigated on 20% cobalt-based catalysts (20% Co/HSA, 20% Co/Si-MMS), which were prepared by home-made supports with high surface areas such as high surface alumina (HSA) and silica mesopores molecular sieve (Si-MMS). In the gas phase reaction by syngas only, 20% Co/Si-MMS catalyst was shown in higher CO conversion and lower carbon dioxide formation than 20% Co/HSA, whereas the olefin selectivity was higher in 20% Co/HSA than in 20% Co/Si-MMS. In the effect of n-hexane added in syngas, the selectivities of $C_{5+}$ and olefin were increased by comparing the supercritical phase reaction with the gas phase reaction in addition to reduce unexpected methane and carbon dioxide.

메탄/천연가스 하이드레이트의 제조 및 특성 비교 분석 (A Comparative Analysis on characteristics and Manufacture of Methane/Natural Gas Hydrates)

  • 이영철;조병학;백영순
    • 한국가스학회지
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    • 제7권3호
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    • pp.32-43
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    • 2003
  • 이 연구는 단성분계(메탄)과 다성분계(천연가스) 하이드레이트의 상평형 조건을 관찰하고, 반응시간에 따른 하이드레이트 생성 거동을 관찰하여 비교 분석하였다. 단성분과 다성분계 하이드레이트의 차이점은 크게 유도지체시간과 안정 영역이다. 반응시 다성분계 하이드레이트는 가스의 성분들이 서로 다른 농도변화를 나타내었으며, 제조된 하이드레이트를 해리시켰을 때도 서로 다른 해리 속도에 의해 각 가스 성분들의 농도가 변화되었다. 압력이 6 MPa이고, 온도가 276.65 K이며, 교반속도가 600 rpm일때 다성분계 하이드레이트 제조시 메탄이외의 여러 가스 성분들에 의해 하이드레이트 핵 생성이 빠르게 진행되어 유도지체시간은 짧다. 그리고 단성분계 하이드레이트는 단일 성분으로 이루어져 있으므로 안정 영역이0.055 mole of $CH_4$/mole of water에서 보다 뚜렷하게 관찰되고, 다성분계 하이드레이트는 안정 영역이 0.04 mole of $CH_4/$mole of water에서 관찰된다.

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산화물 초전도 박막 제작을 위한 오존의 평가 (Evaluation of Ozone for Oxide Superconductor Thin Film Fabrication)

  • 임중관;박용필;이희갑
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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    • pp.1230-1233
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    • 2004
  • Ozone is useful oxidizing gas for the fabrication of oxide thin films. Accordingly researching on oxidizing gas is required. In order to obtain high quality oxide thin films, higher ozone concentration is necessary. In this paper oxidation property was evaluated relation between oxide gas pressure and inverse temperature(CuO reaction). The obtained condition was formulated by the fabrication of Cu metal thin film by co-deposition using the ion Beam Sputtering method. Because the CuO phase peak appeared at the XRD evaluation of the CuO thin film using ozone gas, this study has succeeded in the fabrication of the CuO phase at $825^{\circ}C$.

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연질화층의 성장기구에 미치는 $CO_2$가스의 영향에 관한 연구 (A Study on the Effect of the $CO_2$ Gas on the Growth Mechanism of the Nitrocarburized Layer)

  • 이구현
    • 연구논문집
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    • 통권25호
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    • pp.175-184
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    • 1995
  • Mechanical properties of the gas nitrocarburized product depend on the surface compound layer and the diffusion zone formed. The compound layer improves the wear resistance, and the corrosion resistance. Though phase composition, pore layer and growth rate of the compound layer varies according to the treatment time, temperature and the kind of the steel substrate, they are strongly influenced by the environmental gas composition. In the current study, the growth behavior of the compound layer and diffusion zone of the carbon steel and the alloy steel upon nitrocarburizing treatment at $570^{\circ}C$, and the phase composition and the variation in the growth rate of the compound layer according to the variation of the gas environment which was the medium of the nitriding and carburizing reaction were investigated.

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BSCCO 박막 제작을 위한 산화가스의 특성 (Characteristics of Oxidizing Gas for BSCCO Thin Film Fabrication)

  • 임중관;박용필;장경욱;이희갑
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 춘계학술대회 논문집
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    • pp.110-113
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    • 2005
  • Ozone is useful oxidizing gas for the fabrication of BSCCO thin films. In order to obtain high quality oxide BSCCO thin films, higher ozone concentration is necessary. The growth rates of the films was set in the region from 0.17 to 0.27 nm/min. MgO(100) was used as a substrate. In this paper oxidation property was evaluated relation between oxide gas pressure and inverse temperature(CuO reaction). The obtained condition was formulated by the fabrication of Cu metal thin film by co-deposition using the Ion Beam Sputtering method. Because the CuO phase peak appeared at the XRD evaluation of the CuO thin film using ozone gas, this study has succeeded in the fabrication of the CuO phase at $825^{\circ}C$.

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