• Title/Summary/Keyword: Ni-Catalyst

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Influence of Ni/CeO2-ZrO2 Catalysts on Methane Autothermal Reforming (메탄 자열개질 반응에 대한 Ni/CeO2-ZrO2 촉매의 영향)

  • Kang, Min Goo;Lee, Tae Jun;Lee, Jong Dae
    • Korean Chemical Engineering Research
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    • v.47 no.1
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    • pp.17-23
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    • 2009
  • The catalytic behavior of $Ni/Ce_XZr_{(1-X)}O_2$ loaded on the alumina coated honeycomb monolith was studied for the autothermal reforming reaction of methane. Among the catalysts with the different Ce/Zr ratios, the $Ni/Ce_{0.80}Zr_{0.20}O_2$ Catalyst showed the highest conversion of methane. By investigating the effect of Ni content on the $Ni/Ce_{0.80}Zr_{0.20}O_2$ catalysts, the catalyst loaded with 15wt% Ni had the highest activity. Also, $H_2$ yield was increased as $H_2O/CH_4$ ratio increased. Methane conversion was improved as $O_2/CH_4$ ratio was increased, whereas the yield of $H_2$ was decreased. Among the catalysts tested for 30 hours, $Ni(15wt%)/Ce_{0.80}Zr_{0.20}O_2$ showed the excellent conversion(${\geq}99%$) of methane and the stability at the condition of $GHSV=30,000h^{-1}$, feed ratio S/C/O=2/1/0.5 and reaction temperature $800^{\circ}C$.

Catalytic Combustion of Toluene Over NiO Supported on Mesoporous Silica Catalysts Prepared by Atomic Layer Deposition

  • Jeong, Myung-Geun;Jeong, Bora;Seo, Hyun Ook;Kim, Kwang-Dae;Park, Eun Ji;Sim, Jong Ki;Kim, Dae Han;Cho, Youn Kyuong;Yoon, Hye Soo;Lim, Dong Chan;Kim, Young Dok
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.165-165
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    • 2013
  • Nickel oxide was deposited on mesoporous silica by atomic layer deposition (ALD) consisting of sequential exposures to Ni(cp)2 and $H_2O$. NiO/silica samples were characterized by inductively coupled plasma-mass spectroscopy (ICP-MS), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), etc. The flow-type reactor was used to measure activity of NiO/silica catalyst for catalytic combustion of toluene. The activity of NiO/silica catalyst was evaluated in terms of toluene removal efficiency and selectivity to $CO_2$ and compared with those of bare nickel oxide nanoparticles. In order to investigate influence of reaction temperature on combustion aspect, the catalytic combustion experiments were carried out at various temperatures. We show that both bare and supported NiO can be efficient catalysts for total oxidation of toluene at a temperature as low as $250^{\circ}C$.

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Structural properties and field-emission characteristics of CNTs grown on Ni and Invar catalysts employing an ICP-CVD method (ICP-CVD 방법을 이용하여 Ni 및 Invar 촉매 위에 성장시킨 탄소나노튜브의 구조적 물성 및 전계방출 특성)

  • Hong, Seong-Tae;Kim, Jong-Pil;Park, Chang-Kyun;Uhm, Hyun-Seok;Park, Jin-Seok
    • Proceedings of the KIEE Conference
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    • 2004.07c
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    • pp.1597-1599
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    • 2004
  • Carbon nanotubes (CNTs) are grown on the TiN-coated silicon substrate by varying the thickness of Ni and Invar426 catalyst layers at 600$^{\circ}C$ using an inductively coupled plasma-chemical vapor deposition (ICP-CVD). The Ni and Invar426 catalysts are formed using an RF magnetron sputtering system with various deposition periods. Characterization using various techniques, such as FESEM, HRTEM, and Raman spectroscopy, shows that the physical dimension as well as the crystal quality of grown CNTs are strongly changed by the kind and thickness of catalyst materials. It is also seen that Ni catalysts would be more desirable for vertical-alignment of CNTs compared with Invar426 catalysts. However, the CNTs using Invar426 catalysts display much better electron emission capabilities than those using Ni catalysts. The physical reason for all the measured data obtained are discussed to establish the relationship between structural properties and field-emissive properties of CNTs.

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The Recovery Performance of Co, Ni, and Cu Ions Using Zeolites Synthesized from Inorganic Solid Wastes (무기물계 폐기물로 합성한 제올라이트의 코발트, 니켈, 구리 이온의 회수 성능)

  • Lee, ChangHan
    • Journal of Korean Society on Water Environment
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    • v.28 no.5
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    • pp.723-728
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    • 2012
  • In this study, zeolites were synthesized by a fusion and a hydrothermal methods using a coal fly ash and a waste catalyst. The recovery performance of metal ions on the structure property of synthetic zeolites was evaluated as comparing the adsorption kinetics (Lagergen 2nd order model) and isotherm (Langmuir model) of $Co^{2+},\;Ni^{2+}$, and $Cu^{2+}$ ions. The synthetic zeolites (Z-C1 and Z-W5) were similarly assigned to XRD peaks in a reagent grade Na-A zeolite (Z-WK : $Na_{12}Al_{12}Si_{12}O_{48}\;27.4H_2O$). Adsorption rates of Z-W5 and Z-C1 were in the order of $Cu^{2+}\;>\;Co^{2+}\;>\;Ni^{2+}\;and\;Ni^{2+}\;>\;Cu^{2+}\;>\;Co^{2+}$, respectively. They had influenced upon structure properties of zeolite. Selectivities of metal ions and maximum equilibrium adsorption capacities, $q_{max}$, in Z-C1 and Z-W5 were in the order of $Ni^{2+}$ (127.9 mg/g) > $Cu^{2+}$ (94.7 mg/g) > $Co^{2+}$ (82.6 mg/g) and $Cu^{2+}$ (141.3 mg/g) > $Co^{2+}$ (122.2 mg/g) > $Ni^{2+}$ (87.6 mg/g), respectively. The results show that the synthetic zeolites, Z-C1 and Z-W5, are able to recover metal ions selectively in wastewater.

Characterization of Nanostructure and Electronic Properties of Catalytically Grown Carbon Nanofiber (촉매법으로 제조한 나노탄소섬유의 미세구조 및 전기적 특성 제어 연구)

  • 김명수;우원준;송희석;임연수;이재춘
    • Journal of the Korean Ceramic Society
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    • v.37 no.4
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    • pp.345-353
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    • 2000
  • Carbon nanofibers were prepared from the decomposition of various carbon-containing gases over pure Ni, pure Fe and their alloys with Cu. They yields, properties, and structure of carbon nanofibers obtained from the various reaction conditions were analyzed. Type of reacting gas, reaction temperature and catalyst composition were changed as the reaction variable. With Ni-Cu catalysts, the maximum yields of carbon nanofibers were obtained at temperatures between 550 and 650$^{\circ}C$ according to the reacting gas mixtures of C2H2-H2, C2H4-H2 and C3H8-H2, and the surface areas of the carbon nanofibers produced were 20∼350㎡/g. In the case of CO-H2 mixture, the rapid deposition of carbon nanofibers occurred with Fe-Cu catalyst and the maximum yield were obtained around 550$^{\circ}C$ with the range of surface areas of 140∼170㎡/g. The electrical resistivity of carbon nanofiber regarded as the key property of filler for the application of electromagnetic interference shielding was very sensitive to the type of reactant gas and the catalyst composition ranging 0.07∼1.5Ωcm at a pressure of 10000 psi, and the resistivity of carbon nanofibers produced over pure nickel catalyst were lower than those over alloy catalysts. SEM observation showed that the carbon nanofibers produced had the diameters ranging 20∼300 nm and the straight structure of carbon nanofibers changed into the twisted or helical conformation by the variation of reacting gas and catalyst composition.

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Conversion of CO2 and CH4 through Hybrid Reactor Composed of Plasma and Catalyst at Atmospheric Pressure (상압 플라즈마-촉매 하이브리드 반응기를 통한 CO2와 CH4의 전환처리)

  • Kim, Tae Kyung;Nguyen, Duc Ba;Lee, Won Gyu
    • Applied Chemistry for Engineering
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    • v.25 no.5
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    • pp.497-502
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    • 2014
  • The conversion reaction of methane and carbon dioxide at an atmospheric pressure plasma reactor filled with Ni-$Al_2O_3$ and Ni-$MgAl_2O_4$ catalyst was performed. Effects of various process parameters such as the applied electric power, reaction gas flow rate, reactor temperature, mixing ratio of reactants and the presence of the catalyst on the reaction between methane and carbon dioxide were analyzed. From the analysis of the contribution of the catalyst in the reaction step, even if the temperature raised to $400^{\circ}C$, there was no spontaneous catalytic conversion of methane and carbon dioxide without plasma discharges. When the catalysts for the conversion of methane and carbon dioxide would be adopted to the plasma reactor, the careful selection of suitable catalysts and process parameters should be essential.