• 제목/요약/키워드: catalytic decomposition

검색결과 319건 처리시간 0.026초

고무용 카본블랙 촉매를 이용하는 메탄분해에 의한 수소 생산 (Hydrogen Production by Catalytic Decomposition of Methane over Rubber-Grade Carbon Blacks)

  • 윤기준;류보현;이상엽;한귀영
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2005년도 춘계학술대회
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    • pp.223-226
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    • 2005
  • For $CO_2-free$ hydrogen production and better utilization of the produced carbon, catalytic decomposition of methane over rubber-grade carbon blacks manufactured from coal tar was carried out. The catalytic activities of several domestic carbon blacks were compared. A pelletized carbon black exhibited considerably lower activity and activation energy than the fluffy( loose) carbon black of the same grade. This difference is considered due to the binder that was added during pelletization. For pelletized carbon blacks, a tendency was observed that the activity per unit mass of catalyst increased with the specific surface area of the carbon black. Another tendency was also observed that the activation energy increased with the primary particle size or decrease of the specific surface area.

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촉매습식산화에 의한 Ethylene Glycol의 분해 (Decomposition of Ethylene Glycol by Catalytic Wet Air Oxidation)

  • 안상준;최장승;이동근
    • 한국염색가공학회지
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    • 제13권4호
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    • pp.264-271
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    • 2001
  • Catalytic wet oxidation of ethylene glycol as refractory compound was studied in a batch slurry reactor using lwt% $Pt/A1_2O_3$, lwt% $Pt/TiO_2,\;Mn/CeO_2$(1:1) and 5wt% $Mn/Al_2O_3$. Experiments were conducted to investigate theeffects of temperature, initial ethylene glycol concentration, catalyst dosage and PH on the ethylene glycol decomposition. When compared with the uncatalyzed reaction, the use of catalysts could increase the rate of ethylene glycol decomposition. The lwt% $Pt/A1_2O_3$ catalyst was preferable to the other catalysts for the destructive oxidation of ethylene glycol. The reaction rate was first order with respect to initial concentration of ethylene glycol. In acidic condition the removal efficiency of ethylene glycol was good, but there was a significant leaching of platinum. Small amount of acetic acid, oxalic acid, masonic acid and formic acid as intermediates were detected during catalytic wet air oxidation of ethylene glycol.

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촉매화학기상증착법에 의한 단일벽 탄소나노튜브의 합성과 미세구조 (Synthesis and Microstructure of Single-Walled Carbon Nanotubes by Catalytic Chemical Vapor Deposition Method)

  • 김종식;김관하;김창일
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제55권7호
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    • pp.359-363
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    • 2006
  • Single-walled carbon nanotubes (SWCNTs) with few defects and very small amount of amorphous carbon coating have been synthesized by catalytic decomposition of methane in $H_2$ over well-dispersed metal particles supported on MgO. The yield of SWCNTs was estimated to be 88.5% and the purities of SWCNTs thus obtained were more than 90%. Peak of the radial breathing mode in the Raman spectrum demonstrated that the diameters of synthesized CNTs are in the range 0.4-2.0 nm. Our results also indicated that MgO support materials are useful to a large-scale synthesis of high-quality SWCNTs. Increasing temperature could remarkably increase the yield and also improve the quality of SWCNTs from catalytic decomposition of methane. The morphologies and microstructures of the synthesized carbon materials were characterized by scanning electron microscopy (SEM), Thermogravimetric analysis (TGA), Raman spectroscopy, and X-ray diffraction (XRD).

유동층 반응기에서 카본블랙 촉매를 이용한 프로판의 촉매 분해에 의한 수소생산 연구 (Hydrogen production by catalytic decomposition of propane over carbon black catalyst in a fluidized bed)

  • 윤용희;이승철;한귀영
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2007년도 춘계학술대회
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    • pp.81-85
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    • 2007
  • A fluidized bed reactor is made with quartz. The size of FBR is 0.055 m I.D. and 1.0 m in height. The FBR was employed for the thermocatalytic decomposition of propane to produce hydrogen without $CO_{2}$. The fluidized bed was proposed for the continuous withdraw of product carbons from the reactor. Carbon black DCC-N330 is used to decompose the propane gas. The propane decomposition reaction over carbon black catalyst in a fluidized bed reactor was carried out the temperature range of 600 ${\sim}$ 800 $^{\circ}C$, propane gas velocity of 1.0 ${\sim}$ 4.0$U_{mf}$($1U_{mf}$ = 0.61cm/s) and the catalyst loading of 100 ${\sim}$ 200g. Production of $H_{2}$ such as other reaction temperature, gas velocity, catalytic loading on the reaction rates was investigated. The carbon depositied on the catalyst surface was observed by FE-SEM. The particle size of the carbon black was observed by Particle size analyzer. Resulting production in the experiment was not only hydrogen but also several by-products such as methane, ethylene, ethane, and propylene.

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$N_2O$ 단일 추진제 추력기 개발을 위한 촉매 분해 시험 (Catalytic decomposition of $N_2O$ to develop monopropellant thruster)

  • 진정근;;안성용;권세진
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2009년도 제33회 추계학술대회논문집
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    • pp.269-272
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    • 2009
  • 친환경 추진제인 $N_2O$ 단일추진제 추력기 개발을 위하여 $N_2O$ 촉매 분해 시험을 수행하였다. 백금(Pt), 이리듐(Ir)을 알루미나 펠렛에 코팅한 촉매를 삽입하여 압력을 달리하고 분해 반응이 시작되는 최저 예열 온도를 측정하였다. 실험 결과 Ir이 $N_2O$ 분해 반응에 더 적합하며 최저 요구 예열 온도도 낮게 나타났다. 또한 요구 예열 온도는 챔버 압력이 증가함에 따라 감소하였다. 그러나 지속적인 분해 반응시험을 통해 Ir의 산화 반응에 의한 반응성 저하 현상이 나타남을 실험적으로 확인하였다.

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Ca(OH)2촉매를 이용한 플라즈마 반응에 의한 황산화물의 제거에 관한 연구 (A study of decomposition of sulfur oxides using Calcium hydroxide catalyst by plasma reactions)

  • 김다영;우인성;이선희;김도현;김병철
    • 대한안전경영과학회:학술대회논문집
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    • 대한안전경영과학회 2013년 추계학술대회
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    • pp.547-560
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    • 2013
  • In this study, the air pollutant removal such as sulfur oxides was studied. A combination of the plasma discharge in the reactor by the reaction surface discharge reactor Calcium hydroxides catalytic reactor and air pollutants, hazardous gas SOx, changes in gas concentration, change in frequency, the thickness of the electrode, kinds of electrodes and the addition of simulated composite catalyst composed of a variety of gases, including decomposition experiments were performed by varying the process parameters. The experimental results showed the removal efficiency of 98% in the decomposition of sulfur oxides removal experiment when Calcium hydroxides catalysts and the tungsten(W) electrodes were used. It was increased 3% more than if you do not have the catalytic. If added to methane gas was added the removal efficiency increased decomposition.

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Synthesis of Carbon Nanotubes from Catalytic Decomposition of C2H2 through Pd/Al2O3 Catalysts

  • Han, Ju-Tack;Woo, Ja-Hee;Kim, Hae-Sic;Jee, Jong-Gi
    • Bulletin of the Korean Chemical Society
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    • 제24권12호
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    • pp.1771-1774
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    • 2003
  • CNTs have been synthesized by catalytic $C_2H_2$ decomposition through $Pd/Al_2O_3$ at low temperature. The CNTs were grown to a length of about 10 ${\mu}$m and diameter 150-200 nm with multiwalled structure. Pd catalysts have two major roles; one is the active catalyst for $C_2H_2$ decomposition, the other is a nucleation site of CNT's growth.

Numerical study on the design of urea decomposition chamber in LP SCR system

  • Um, Hyung Sik;Kim, Daehee;Kim, Keon Ho
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제11권1호
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    • pp.307-313
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    • 2019
  • In order to design efficient Urea Decomposition Chamber (UDC) for the Low Pressure (LP) Selective Catalytic Reduction (SCR) system, numerical simulations were conducted with respect to various design parameters. The design parameters examined in this simulation include the chamber diameter, inlet and outlet shape of chamber, and urea injection point. Reaction kinetics for the urea decomposition was proposed and validated with the experimental data in the range of $300{\sim}450^{\circ}C$. The effects of design parameters on the performance of UDC were evaluated by the calculated urea conversion and pressure drop. As a result, the local optimum design values were derived by the parametric study.

폐건전지에서 회수된 Mn을 이용한 오존분해 특성 연구 (A Study on the Charateristics for Ozone Decomposition over Recovered Mn from Spent Betteries)

  • 김거종;홍성창
    • 공업화학
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    • 제24권2호
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    • pp.161-164
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    • 2013
  • 본 연구에서는, 폐건전지로부터 회수된 특정 성분들을 이용하여 오존분해 촉매로서의 적용성을 평가하였다. 폐건전지에서 축출된 성분 중, Mn의 함량이 오존분해 반응에 주요 인자임을 보였다. 또한, Zn 함량에 따라 deactivation rate와 높은 상관성을 나타냈으며, K 함량은 오존분해 반응과 상관성이 없음을 나타냈다. 그리고 $TiO_2$를 첨가하여 제조한 촉매는 Mn 함량의 감소로 인한 효율 저하를 나타냈으며, Mn 구조상의 특징은 오존분해 반응과 상관성이 없음을 나타냈다.

유동층 반응기에서 카본블랙 촉매를 이용한 프로판의 촉매 분해에 의한 수소생산 연구 (Hydrogen production by catalytic decomposition of propane over carbon black catalyst in a fluidized bed)

  • 정재욱;남우석;윤기준;이동현;한귀영
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2006년도 춘계학술대회
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    • pp.85-88
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    • 2006
  • A fluidized bed reactor made of quartz with 0.055m I.D. and 1.0m in height was employed for the thermocatalytic decomposition of propane to produce $CO_2$-free hydrogen. The fluidized bed was proposed for the continuous withdraw of product carbons from the reactor. The propane decomposition rate used carbon black N33O as a catalyst. The propane decomposition reaction was carried out at the temperature range of $600{\sim}800^{\circ}C$, paropane gas velocity of $1.0 U_{mf}\;3.0U_{mf}$ and the operating pressure of 1.0 atm. Effect of operating parameters such as reaction temperature, gas velocity on the reaction rates was investigated. The carbon which was by-product of methane decomposition reaction was deposited on the catalyst surface that was observed by SEM. Resulting production in our experiment were not only hydrogen but also several by products such as methane, ethylene, ethane, and propylene.

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