• 제목/요약/키워드: $Pt/Al_2O_3-Ce_2O$

검색결과 19건 처리시간 0.025초

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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일단 WGS반응용 백금 담지 촉매 최적화 (Optimization of Supported Pt Catalysts for Single Stage Water Gas Shift Reaction)

  • 김기선;정대운;구기영;윤왕래;노현석
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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    • pp.156.2-156.2
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    • 2011
  • 본 연구에서는 일단 수성가스전이반응 (Single stage water gas shift reaction)을 위해 높은 활성을 가진 백금 담지 촉매를 함침법 (Incipient wetness impregnation method)으로 제조하여 높은 공간 속도 (Gas hourly space velocity) $45,515h^{-1}$에서 담체에 따른 촉매 활성을 평가하였다. 담체는 $CeO_2$, $ZrO_2$, MgO, MgO-$Al_2O_3$ (MgO = 30 wt%) 그리고 $Al_2O_3$를 사용하였으며 백금의 담지량은 1 wt%로 고정하였다. BET, XRD, TPR, CO-chemisorption 분석을 통하여 담체의 구조적 특성이 촉매 활성에 미치는 영향에 대하여 조사하였다.

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연료전지용 CO의 산화를 위한 백금/알루미나 촉매의 성능향상에 관한 연구 (Enhancement of Catalytic Activity of Pt/Alumina by a Novel Pretreatment Method for the CO Oxidation for Fuel Cell Applications)

  • 조명찬
    • 한국환경과학회지
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    • 제17권12호
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    • pp.1307-1314
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    • 2008
  • Hydrogen gas is used as a fuel for the proton exchange membrane fuel cell (PEMFC). Trace amount of carbon monoxide present in the reformate $H_2$ gas can poison the anode of the PEMFC. Therefore, preferential oxidation (PROX) of CO is essential for reducing the concentration of CO from a hydrogen-rich reformate gas. In this study, conventional Pt/$Al_2O_3$ catalyst was prepared for the preferential oxidation of CO. The effects of catalyst preparation method, additive, and hydrogen on the performances of PROX reaction of CO were investigated. Water treatment and addition of Ce enhanced catalytic activity of the Pt/$Al_2O_3$ catalyst at low temperature below $100^{\circ}C$.

Lead Tolerance of Noble Metal Catalysts for CO Oxidation

  • Chang, Tu-Won;Sohn, Youn-Soo
    • Bulletin of the Korean Chemical Society
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    • 제7권1호
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    • pp.12-15
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    • 1986
  • Lead tolerance of $Pt/Al_2O_3$ catalysts was evaluated for CO oxidation depending on the properties of the alumina supports and base metals added as promoter. Among the four different alumina supports, the support with a large macropore volume (0.45 cc/g) and 5% Ce has shown the best resistence to lead poisoning. Most of the base metals added to the Pt-catalysts were found to be ineffective for improving lead resistence, but boron has shown an excellent lead tolerence, although it decreases the initial catalytic activity.

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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PEMFC Operation Connected with Methanol Reformer System

  • Lee, Jung-Hyun;Park, Sang-Sun;Shul, Yong-Gun;Park, Jong-Man;Kim, Dong-Hyun;Kim, Ha-Suck;Yoo, Seung-Eul
    • Carbon letters
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    • 제9권4호
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    • pp.303-307
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    • 2008
  • The studies on integrated operation of fuel cell with fuel processor are very essential prior to its commercialization. In this study, Polymer Electrolyte Membrane Fuel Cell (PEMFC) was operated with a fuel processor, which is mainly composed of two parts, methanol steam reforming reaction and preferential oxidation (PROX). In fuel processor, ICI 33-5 (CuO 50%, ZnO 33%, $Al_2O_3$ 8%, BET surface area: $66\;m^2g^{-1}$) catalyst and CuO-$CeO_2$ catalyst were used for methanol steam reforming, preferential oxidation (PROX) respectively. PEMFC was operated by hydrogen fuel generated from fuel processor. The resulting gas from PROX reactor is used to operate PEMFC equipped with our prepared anode and cathode catalyst. PtRu/C catalyst gives more tolerance to CO.

암모니아로부터 수소 제조를 위한 다양한 촉매 활성 테스트에 관한 연구 (A Study on Activity Testing of Various Catalysts for Hydrogen Production from Ammonia)

  • 이재혁;신경하;강진실;신현희;박세연;최유진;송완규;안호근
    • 한국수소및신에너지학회논문집
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    • 제34권6호
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    • pp.587-593
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    • 2023
  • This research project focused on the production of hydrogen through ammonia decomposition reactions while investigating how the reactivity of this process varies when employing different catalysts. Several metal oxide supports (Al2O3, La2O3, CeO2) were utilized as catalysts, with active metals from both the transition metal group (Co, Ni, Fe, Cr, Cu) and the noble metal group (Ru, Rh, Pd, Pt) impregnated onto these supports. Furthermore, the study examined how the reactivity evolves with changes in reaction temperature when employing the prepared catalysts. Additionally, the research delved into the distinctive activation energies associated with each of the catalysts. In this research, In the noble metal catalyst system, the order of high activity for ammonia decomposition reaction to produce hydrogen is Ru > Rh > Pt ≈ Pd. In the transition metal catalyst system, the order of high activity is Co > Ni > Fe > Cr > Cu.

Overview of the Effect of Catalyst Formulation and Exhaust Gas Compositions on Soot Oxidation In DPF

  • Choi Byung Chul;FOSTER D.E.
    • Journal of Mechanical Science and Technology
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    • 제20권1호
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    • pp.1-12
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    • 2006
  • This work reviews the effects of catalyst formulation and exhaust gas composition on soot oxidation in CDPF (Catalytic Diesel Particulate Filter). DOC's (Diesel Oxidation Catalysts) have been loaded with Pt catalyst (Pt/$Al_{2}O_3$) for reduction of HC and CO. Recent CDPF's are coated with the Pt catalyst as well as additives like Mo, V, Ce, Co, Fe, La, Au, or Zr for the promotion of soot oxidation. Alkali (K, Na, Cs, Li) doping of metal catalyst tends to increase the activity of the catalysts in soot combustion. Effects of coexistence components are very important in the catalytic reaction of the soot. The soot oxidation rate of a few catalysts are improved by water vapor and NOx in the ambient. There are only a few reports available on the mechanism of the PM (particulate matter) oxidation on the catalysts. The mechanism of PM oxidation in the catalytic systems that meet new emission regulations of diesel engines has yet to be investigated. Future research will focus on catalysts that can not only oxidize PM at low temperature, but also reduce NOx, continuously self-cleaning diesel particulate filters, and selective catalysts for NOx reduction.