• 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.

• 청정기술
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• 제23권3호
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• pp.314-324
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• 2017

To verify the viability of Co, Ru and Zr-based catalyst for $CO_2$ (dry) reforming reaction, catalysts were fabricated using cordierite, silicon carbide and rota monolithic substrates, and they were compared with the conventional $Co-Ru-Zr/SiO_2$ catalyst in terms of performance and durability. Cordierite monolith was showed high activity with the least amount of active component. In addition, when Cordierite monolith was coated with Co-Ru-Zr in various ways, most excellent performance was showed at a precursor solution coating method. In particular, when 0.9 wt% Co-Ru-Zr/Cordierite was used for reaction, it was observed that 95% $CO_2$ conversion was maintained for 300 h at $900^{\circ}C$.

• Bulletin of the Korean Chemical Society
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• 제32권10호
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• pp.3660-3665
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• 2011

CO-tolerant PtMo/C alloy electrocatalyst was prepared by a colloidal method, and its electrocatalytic activity toward CO oxidation was investigated. Electrochemical study revealed that the alloy catalyst significantly enhanced catalytic activity toward the electro-oxidation of CO compared to Pt/C counterpart. Cyclic voltammetry suggested that Mo plays an important role in promoting CO electro-oxidation by facilitating the formation of active oxygen species. The effect of Mo on the electronic structure of Pt was investigated using X-ray absorption spectroscopy to elucidate the synergetic effect of alloying. Our in-depth spectroscopic analysis revealed that CO is less strongly adsorbed on PtMo/C catalyst than on Pt/C catalyst due to the modulation of the electronic structure of Pt d-band. Our investigation shows that the enhanced CO electrooxidation in PtMo alloy electrocatalyst is originated from two factors; one comes from the facile formation of active oxygen species, and the other from the weak interaction between Pt and CO.

• Bulletin of the Korean Chemical Society
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• 제25권8호
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• pp.1253-1256
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• 2004

• 오토저널
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• 제3권1호
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• pp.46-53
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• 1981

This paper describes emission control of hydrocarbon and carbon-monoxide due to oxidizing catalyst. The experiment was performed on a precious metal pelleted catalyst(Pt). The factors of the efficiency for purification due to oxidizing catalyst are space velocity, temperature, composition of exhaust gas and supplementary air. The experiment was carried out to control the factors of efficiency for purification. The results of experimental study show that temperature of catalytic converter, supplementary air and space velocity affected the efficiency for purification of hydrocarbon and carbon monoxide.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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• pp.670-673
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• 2002

We have investigated the catalyst effect on the growth and structure of CNTs using thermal chemical vapor deposition. The respective growth rate of CNTs shows that the performance of catalysts is in the order of nickel (Ni)>cobalt (Co)>iron (Fe). The average diameter of CNTs follows the sequence of Fe, Co, and Ni catalysts. The structure of CNTs reveals almost same morphology regardless of catalyst but the crystallinity of CNTs is largely dependent on catalyst. The crystallinity of CNTs synthesized from Fe catalyst is higher than that from Ni or Co catalyst. We demonstrate that the growth rate, the diameter, and the crystallinity of CNTs can be manipulated by selecting the catalysts.

• 한국전기전자재료학회논문지
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• 제21권5호
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• pp.447-452
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• 2008

We synthesized nano-sized $La_{1-x}Sr_xCoO_3$ ($x=0.1{\sim}0.4$) cathode catalyst for the zinc air secondary batteries by citrate method, And we measured the cathode's electrochemical characteristics according to content of strontium compose the cathode catalyst. We controlled the pH of precursor solution by 10 in the process of manufacturing the precursor, We heat treated the prepared precursor at various calcination temperature ($500{\sim}900^{\circ}C$), and examined the optimum calcinations temperature by XRD analysis and electrochemical evaluation. We examined the ORR (oxygen reduction reaction) and OER (oxygen evolution reaction) performance of the prepared $La_{1-x}Sr_xCoO_3$ catalyst powder. When we consider ORR and OER performance simultaneously, $La_{0.7}Sr_{0.3}CoO_3$ catalyst has shown the best performance because of its lowest voltage deference between charge and discharge.

• 공업화학
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• 제3권1호
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• pp.72-80
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• 1992

상이동촉매를 사용하여 Group 6의 $M(CO)_4$(2, 2'-bipyridine)[M=Cr, Mo, W]을 $M(CO)_6$의 CO 리간드를 2개의 비공유 전자쌍 주게인 2, 2'-bipyridine으로 치환하여 합성할 때 촉매의 종류와 용매가 생성물의 수율에 미치는 영향을 고찰하였다. 촉매는 형태, 중심양이온 및 음이온의 종류, 양이온에 결합된 알킬기와 아릴기의 종류, 그리고 사슬길이가 다른 다양한 촉매를 사용하였다.

• 한국수소및신에너지학회논문집
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• 제22권2호
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• pp.249-256
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• 2011

In this study, the Ni-based catalysts for the production of synthetic natural gas were prepared by various preparation methods such as the co-precipitation, precipitation, impregnation and physical mixing methods. The ranges of the reaction conditions were the temperatures of 250~$350^{\circ}C$, $H_2$/CO mole ratio of 3.0, the pressures of 1 atm and the space velocity of 20000 $ml/g_{-cat{\cdot}}{\cdot}h$. It was found that the catalyst prepared by precipitation method had higher CO conversion than the catalyst prepared by co-precipitation method. While the catalyst prepared by precipitation method had the formation of NiO structure, the catalyst prepared by co-precipitation method had the formation of $NiAl_2O_4$ structure. It was confirmed that Ni-based catalyst prepared by the physical mixing method had the lowest CO conversion because it was deactivated by the production of $Ni_3C$ during the methanation. As a result, it was shown clearly that Ni-based catalysts prepared by impregnation method expressed the highest catalytic activity in CO methanation.

• 한국대기환경학회지
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• 제21권6호
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• pp.667-673
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• 2005

An EBeam (electron beam)-catalyst coupling technique has been developed to control aromatic volatile organic compounds (VOCs) by annexing the catalyst with already existing EBeam technology. In this study, toluene emitted from various industrial coating processes was selected as a representative VOC. The concentration of toluene of concern was 200 ppm. There was an increase in the removal efficieny of toluene by increasing the absorbed dose (kGy) in the EBeam-only and the EBeam-catalyst coupling systems. Compared to EBeam-only system under the same existing EBeam-Pt $1\%$ coupling conditions, EBeam-Pt $1\%$ coupling system revealed 36, 29, 30$\%$ increase in toluene treatmenet at (5, 6.7, 8.7 kGy), respectively. In addition, $O_{3}$ was decreased and CO, $CO_{2}$ were increased by increasing the absorbed dose (kGy) in the EBeam-catalyst (Pt $1\%$, Cu $1\%$) coupling systems. Therefore, it was concluded that the EBeam-catalyst coupling system had a synergy effect on toluene control, compared to the EBeam-only system.