• 제목/요약/키워드: catalyst support

검색결과 364건 처리시간 0.031초

Se-TiO2 지지체를 이용한 V/W/TiO2 NH3-SCR 촉매의 반응 특성 연구 (The Study of Reaction Characteristics of V/W/TiO2 Catalyst Using Se-TiO2 Support On NH3-SCR Reaction)

  • 이연진;원종민;안석현;홍성창
    • 공업화학
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    • 제32권6호
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    • pp.599-606
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    • 2021
  • 본 연구는 질소산화물 제거를 위하여 암모니아를 환원제로 사용하는 선택적 촉매 환원법에 있어 지지체에 셀레늄을 첨가하여 300 ℃ 이하에서 V2O5/WO3/TiO2의 반응 활성을 증진시키기 위한 실험 및 반응특성 연구를 수행하였다. 졸-겔법으로 Se-TiO2 및 TiO2를 합성하였으며, 이를 지지체로 하여 V2O5/WO3/TiO2 및 V2O5/WO3/Se-TiO2 촉매를 제조하여 상용 촉매와 반응 활성을 비교하였다. 실험 결과, 졸-겔법으로 합성한 TiO2를 사용한 촉매의 탈질 효율이 상용 TiO2를 사용하여 제조한 촉매보다 낮은 결과를 보였으나 셀레늄을 첨가함에 따라 탈질 효율이 증진되었다. 따라서 BET, XRD, Raman, H2-TPR 및 FT-IR분석을 통하여 셀레늄의 첨가가 촉매의 구조에 미치는 영향을 분석하였으며 셀레늄 첨가에 의한 비표면적의 증가와 단량체 및 복합체 바나듐 종의 형성이 반응 특성에 미치는 영향을 확인하였다.

Preparation, Characterization and First Application of Aerosil Silica Supported Acidic Ionic Liquid as a Reusable Heterogeneous Catalyst for the Synthesis of 2,3-Dihydroquinazolin-4(1H)-ones

  • Yassaghi, Ghazaleh;Davoodnia, Abolghasem;Allameh, Sadegh;Zare-Bidaki, Atefeh;Tavakoli-Hoseini, Niloofar
    • Bulletin of the Korean Chemical Society
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    • 제33권8호
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    • pp.2724-2730
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    • 2012
  • A new heterogeneous acidic catalyst was successfully prepared by impregnation of silica (Aerosil 300) by an acidic ionic liquid, named 1-(4-sulfonic acid)butylpyridinium hydrogen sulfate [$PYC_4SO_3H$][$HSO_4$], and characterized using FT-IR spectroscopy, the $N_2$ adsorption/desorption analysis (BET), thermal analysis (TG/DTG), and X-ray diffraction (XRD) techniques. The amount of loaded acidic ionic liquid on Aerosil 300 support was determined by acid-base titration. This new solid acidic supported heterogeneous catalyst exhibits excellent activity in the synthesis of 2-aryl-2,3-dihydroquinazolin-4(1H)-ones by cyclocondensation reaction of 2-aminobenzamide with aromatic aldehydes under solvent-free conditions and the desired products were obtained in very short reaction times with high yields. This catalyst has the advantages of an easy catalyst separation from the reaction medium and lower problems of corrosion. Recycling of the catalyst and avoidance of using harmful organic solvent are other advantages of this simple procedure.

승용차용 세라믹 촉매 담체의 열적 내구성의 실험적 평가 (Experimental Estimation of Thermal Durability in Ceramic Catalyst Supports for Passenger Car)

  • 백석흠;김성용;승삼선;양협;주원식;조석수
    • 대한기계학회논문집A
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    • 제31권12호
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    • pp.1157-1164
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    • 2007
  • Ceramic honeycomb structures have performed successfully as catalyst supports for meeting hydrocarbon, carbon monoxide and nitrous emissions standards for gasoline-powered vehicles. Three-way catalyst converter has to withstand high temperature and thermal stress due to pressure fluctuations and vibrations. Thermal stress constitutes a major portion of the total stress which the ceramic catalyst support experiences in service. In this study, temperature distribution was measured at ceramic catalyst supports. Thermal durability was evaluated by power series dynamic fatigue damage model. Radial temperature gradient was higher than axial temperature gradient. Thermal stresses depended on direction of elastic modulus. Axial stresses are higher than tangential stresses. Tangential and axial stresses remained below thermal fatigue threshold in all engine operation ranges.

메탄의 이산화탄소 개질반응과 사용된 Ni 촉매 표면에서의 CNT 성장 ($CO_2$ reforming of $CH_4$ and growth of CNT on Ni catalyst)

  • 김희연;정남조;송광섭
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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    • pp.511-512
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    • 2008
  • For the $CO_2$ reforming of $CH_4$, Ni catalyst was supported on La-hexaaluminate or on $\gamma$-$Al_2O_3$. The catalytic activities of Ni/La-hexaaluminate catalysts were measured at $700^{\circ}C$ using gas chromatography (GC) for 72 h, and the reaction was maintained up to 72 hfor the investigation of catalyst deactivation. The surface of each catalyst after 72 h reaction was investigated using SEM and TEM, and the composition of the carbon deposits was investigated by using EA, TPO and TGA. Ni/La-hexaaluminate shows higher resistance to coke deposition than conventional Ni/$Al_2O_3$ which seems to be due to strong interaction between Ni and the support material. As a result of the reforming reaction, various types of carbon deposits were created on catalyst surface and the amounts of them were much smaller in the case of La-hexaaluminate than on $Al_2O_3$.

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$N_2O$ 추진제 분해 촉매의 고온 내열 특성 연구 (Study on the Characteristics of Thermal-resistance Catalyst for $N_2O$ Propellant Decomposition)

  • 백진오;김태규
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2010년도 제34회 춘계학술대회논문집
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    • pp.373-376
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    • 2010
  • 아산화질소를 추진제로 사용하기 위해 아산화질소의 촉매 분해 특성과 고온 하에서 내열성을 연구하였다. 기존의 Ru 촉매의 내열성을 개선하기 위해 추가적으로 $Al_2O_3$ 지지체에 Si를 담지시킨 후 Ru을 담지하였다. 관형 반응기를 이용하여 반응온도에 따른 아산화질소의 전환율을 측정하고, Si 첨가에 의한 분해특성에 대해서 연구하였다. 반응온도가 높을수록 전환율이 우수했고, Ru/$Al_2O_3$-Si 촉매가 Ru/$Al_2O_3$ 촉매보다 높은 전환율을 보였다.

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수전해용 Ir/TiO2 산소 발생 촉매의 제조 및 성능 평가 (Synthesis and Evaluation of Ir/TiO2 OER catalyst for PEM water electrolysis)

  • 송민아;정혜영;이해지;최윤기;문상봉
    • 한국수소및신에너지학회논문집
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    • 제27권5호
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    • pp.471-477
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    • 2016
  • In this research, the Ir supported $TiO_2$ (P25) catalyst was prepared by precipitation method for oxygen evolution reaction. The $Ir/TiO_2$ catalyst was synthesised by reduction reaction using reducing agent. Physiochemical characterizations of synthesized $Ir/TiO_2$ catalyst was studied by means of SEM, EDS mapping, TEM and XRD. The Electrochemical characterizations were tested by using the technique of CV and LSV by RDE and Potentiostat. Physicochemical properties were characterized with XRD where Iridium metal morphology and Ir(111) and Ir(222) peaks were founded. $Ir0.2Ru0.8O_2$ exhibited higher OER activity than $Ir0.5Ru0.5O_2$ followed by $Ir/TiO_2$ and $IrO_2$.

A Study on the Sulfur-Resistant Catalysts for Water Gas Shift Reaction IV. Modification of $CoMo/γ-Al_2O_3$ Catalyst with K

  • 박진남;김재현;이호인
    • Bulletin of the Korean Chemical Society
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    • 제21권12호
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    • pp.1239-1244
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    • 2000
  • A study of K addition to the catalyst of CoMo/ ${\gamma}-Al_2O_3$ was studied. The catalyst with 10 at% of K to Mo atoms in 3C10M, the catalyst added 3 wt% CoO to 10 wt% $MoO_3/{\gamma}-Al_2O_3$, showed the highest activity for water gas shift reaction. The addition of K retarded the reducibility of cobalt-molybdenum catalysts. It gave, however, good dispersion and large BET surface area to the catalysts which were attributed to the disappearance of polymolybdate clustyer such as $Mo_7O_{24}^{6-}$ and the formation of small Mo$O_4^{2-}$ cluster. It was confirmed by the analyses of pore size distribution, activation energy, Raman spectroscopy, and electron diffraction. The activation energies and the frequency factors of the catalysts 3C10M and 5KC10M (the catalyst added 5 at% K for Mo to the catalyst 3C10M) were 43.1 and 47.8 kJ/mole, and 4,297 and 13,505 $sec^{-1}$, respectively. These values were also well correlated with our suggestion. These phenomena were attributed to the direct interaction between K and CoMo oxides irrelevant to the support.

$Ni/\gamma -Al_2O_3$ Catalyst Prepared by Liquid Phase Oxidation for Carbon Dioxide Reforming of Methane

  • 정경수;조병율;이호인
    • Bulletin of the Korean Chemical Society
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    • 제20권1호
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    • pp.89-94
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    • 1999
  • Carbon dioxide reforming of methane on Ni/γ-Al2O3 catalyst was studied. A new 10 wt% Ni/γ-Al2O3 catalyst prepared by the liquid phase oxidation method (L10O) exhibited much higher activity as well as resistances to both sintering and coke formation during the reaction than the catalyst prepared by the conventional impregnation method (D10). The electrically strong attractive interaction between nickel and support during the liquid phase oxidation process and the resultant high nickel dispersion made the L10 have superior activity and stability to the D10. To elucidate the results, the experiments with nickel catalysts on the other supports as well as 7-AI203 were performed. The effect of sodium as a promoter was also studied.

수소제조를 위한 다공성 FeCrAl 금속 합금 Foam의 NiO 촉매 담지 및 미세구조 분석 (Synthesis and Microstructure Analysis of NiO Catalysts Coated on the FeCrAl Metal Alloy Foam for Hydrogen Production)

  • 이유진;안건형;박만호;이창우;최상현;정주용;조성종;이근재;안효진
    • 한국재료학회지
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    • 제24권8호
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    • pp.393-400
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    • 2014
  • NiO catalysts were successfully coated onto FeCrAl metal alloy foam as a catalyst support via a dip-coating method. To demonstrate the optimum amount of NiO catalyst on the FeCrAl metal alloy foam, the molar concentration of the Ni precursor in a coating solution was controlled, with five different amounts of 0.4 M, 0.6 M, 0.8 M, 1.0 M, and 1.2 M for a dip-coating process. The structural, morphological, and chemical bonding properties of the NiO-catalyst-coated FeCrAl metal alloy foam samples were assessed by means of field-emission scanning electron microscopy(FESEM), scanning electron microscopy-energy dispersive spectroscopy(SEM-EDS), X-ray diffraction(XRD), and X-ray photoelectron spectroscopy(XPS). In particular, when the FeCrAl metal alloy foam samples were coated using a coating solution with a 0.8 M Ni precursor, well-dispersed NiO catalysts on the FeCrAl metal alloy foam compared to the other samples were confirmed. Also, the XPS results exhibited the chemical bonding states of the NiO phases and the FeCrAl metal alloy foam. The results showed that a dip-coating method is one of best ways to coat well-dispersed NiO catalysts onto FeCrAl metal alloy foam.