• Bulletin of the Korean Chemical Society
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• 제34권7호
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• pp.2105-2110
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• 2013

Carbon-fiber-supported NiO catalytic filters for oxidation of volatile organic compounds were prepared by electroless Ni-P plating and subsequent annealing processes. Surface structure and crystallinity of NiO film on carbon fiber could be modified by post-annealing at different temperatures (500 and $650^{\circ}C$). Catalytic thermal decompositions of toluene over these catalytic filters were investigated. $500^{\circ}C$-annealed sample showed a higher catalytic reactivity toward toluene decomposition than $650^{\circ}C$-annealed one under same conditions, despite of its lower surface area and toluene adsorption capacity. X-ray diffraction and X-ray photoelectron spectroscopy studies suggest that amorphous structures of NiO on $500^{\circ}C$-annealed catalyst caused the higher reactivity for oxidation of toluene than that of $650^{\circ}C$-annealed sample with a higher crystallinity.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.217-217
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• 2013

Carbon-fiber-supported NiO catalytic filters for oxidation of volatile organic compounds were prepared by electroless Ni-P plating and subsequent annealing processes. Surface structure and crystallinity of NiO film on carbon fiber could be modified by post-annealing at different temperatures (500 and $650^{\circ}C$. Catalytic thermal decompositions of toluene over these catalytic filters were investigated. $500^{\circ}C$ annealed sample showed a higher catalytic reactivity toward toluene decomposition than $650^{\circ}C$ annealed one under same conditions, despite of its lower surface area and toluene adsorption capacity. X-ray diffraction and X-ray photoelectron spectroscopy studies suggested that amorphous structures of NiO on $500^{\circ}C$ annealed catalyst caused the higher reactivity for oxidation of toluene than that of $650^{\circ}C$ annealed sample with a higher crystallinity.

• 한국수소및신에너지학회논문집
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• 제34권5호
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• pp.535-548
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• 2023

The intermittent nature of renewable energy is a challenge to overcome for safety and stable performance in water electrolysis systems linked to renewable energy. Oxygen removal using the catalyst is suitable for maintaining the oxygen concentration in hydrogen below the explosive level (4%) even in intermittent power supply. Metals such as Pd, Pt, and Ni are expected to be effective materials due to their hydrogen affinity. The oxygen removal performance was compared under high hydrogen concentration conditions by loading on γ-Al₂O₃ with high reactivity and large surface area. The characteristics of the catalyst before and after the reaction were analyzed through X-ray diffraction, transmission electron microscope, H₂-temperature programmed reduction, X-ray photoelectron spectroscope, etc. The Pd catalyst that showed the best performance was able to lower 2% oxygen to less than 5 ppm. Changes in catalyst characteristics after the reaction indicate that oxygen vacancies are related to oxygen removal performance and catalyst deactivation.

• Bulletin of the Korean Chemical Society
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• 제35권11호
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• pp.3205-3208
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• 2014

Catalytic gasification of cellulose was carried out in a U-type fixed reactor with Ni loaded MSU-F catalyst (Ni/MSU-F) and Ni loaded ${\gamma}-Al_2O_3$ (Ni/${\gamma}-Al_2O_3$). The characteristics of the catalysts were analyzed by using X-ray diffraction, $H_2$-temperature programmed reduction, and Brunauer-Emmett-Teller analyses. The operation conditions of catalytic gasification reactions were $750^{\circ}$ and 0.2 equivalence ratio. Air was used as gasification agent. Catalytic gasification characteristics, such as gas yield and gas composition ($H_2$, CO, $CO_2$, $C_1-C_4$), were measured and calculated. The gas yield of Ni/MSU-F was much higher than that of Ni/${\gamma}-Al_2O_3$. Especially high amount of hydrogen was produced by Ni/MSU-F.

• 한국진공학회지
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• 제22권6호
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• pp.277-284
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• 2013

아세틸렌과 수소기체를 원료기체로 하고 육불화황을 첨가기체로 하여 열화학 기상 증착하에서 탄소코일을 합성하였다. 이 때 산화실리콘 기판위의 니켈막을 탄소코일 성장의 촉매로 사용하였다. 성장된 탄소코일의 생성밀도, 형상, 기하구조 등을 수소 플라즈마 전처리의 유무에 따라 조사하였다. 상대적으로 짧은 시간(1분)의 수소 플라즈마 전처리는 탄소 마이크로 코일을 우세하게 성장시켰다. 긴 시간(30분)동안의 수소플라즈마 전처리는 탄소마이크로 성장 축을 따라 수많은 탄소 나노코일이 들어붙어 있는 특이한 구조를 보였다. 이 특이한 구조는 매우 작은 니켈 촉매의 알갱이를 효과적으로 지지할 수 있는 촉매 지지대로서의 역할을 할 수 있을 것으로 예견되었다.

• 한국응용과학기술학회지
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• 제28권3호
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• pp.321-328
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• 2011

The autothermal reforming reaction of methane was investigated to produce hyd rogen with Ni/$CeO_2-ZrO_2$, Ni/$Al_2O_3$-MgO and Ni-Ru/$Al_2O_3$-MgO catalysts. Honeycomb metalli c monolith was applied in order to obtain high catalytic activity and stability in autothermal r eforming. The catalysts were characterized by XRD, BET and SEM. The influence of various catalysts on hydrogen production was studied for the feed ratio($O_2/CH_4$, $H_2O/CH_4$). The $O_2/CH_4$ and $H_2O/CH_4$ ratio governed the methane conversion and temperature profile of reactor. Th e reactor temperature increased as the reaction shifted from endothermic to exothermic reactio n with increasing $O_2/CH_4$ ratio. Among the catalysts used in the experiment, the Ni-Ru/$Al_2O_3$-MgO catalyst showed the highest activity. The 60% of $CH_4$ conversion was obtained, and th e reactor temperature was maintained $600^{\circ}C$ at the condition of GHSV=$10000h^{-1}$ and feed ratio S/C/O=0.5/1/0.5.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2012년도 춘계학술발표회 논문집
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• pp.218-219
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• 2012

Carbon coils could be synthesized using $C_2H_2/H_2$ as source gases and $SF_6$ as an incorporated additive gas under thermal chemical vapor deposition system. Prior to the carbon coils deposition reaction, two kinds of samples having different combination of Ni catalyst and substrate were employed, namely a commercially-made $Al_2O_3$ ceramic boat with Ni powders and a commercially-made $Al_2O_3$ substrate with Ni layer. By using a commercially-made $Al_2O_3$ ceramic boat, the production yield of carbon coils could be enhanced as much as 10 times higher than that of $Al_2O_3$ substrate. Furthermore, the dominant formation of the microsized carbon coils could be obtained by using $Al_2O_3$ ceramic boat.

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2003년도 추계총회 및 연구발표회 초록집
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• pp.151.1-151
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• 2003

• 한국수소및신에너지학회논문집
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• 제19권1호
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• pp.10-17
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• 2008

This study has been focused on the partial oxidation(POX) of n-octane over Rh-containing catalysts supported on alumina. The catalysts for this reaction were prepared by incipient wetness(IW) and co-gel(CG) methods, followed by the calcination at $900{\circ}C$ or $1,200{\circ}C$. When applied to the POX of n-octane carried out at $600{\circ}C$ with C/O=3 and GHSV=3,450/h, the catalyst prepared by the CG method and calcined at $1,200{\circ}C$ showed the best activity, yielding 42% syngas($H_2$+CO) with the $H_2$/CO ratio of $2{\sim}2.4$. To enhance the activity and stability of catalysts, bimetallic catalysts were synthesized by the CG method. As a result, the performance of Rh-Ni/$Al_2O_3$ catalyst was superior to that of Rh/$Al_2O_3$ catalyst in terms of the catalyst stability, due to the retarding effect on the Rh-to-$Rh_2O_3$ transition by the addition of Ni. This result was confirmed by XRD, TEM, and TPR characterizations.

• Bulletin of the Korean Chemical Society
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• 제35권9호
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• pp.2615-2620
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• 2014

Ni/$La_2O_3$ with a high dispersion was prepared by reduction of $La_2O_3$ perovskite oxide to examine the catalytic activity for the $CO_2-CH_4$ reaction. The Ni/$La_2O_3$ catalyst was found to be highly active for the reaction. The ratios of $H_2$/CO were measured in a flow of the reaction mixture containing $CO_2/CH_4$/Ar using an on-line gas chromatography system operated at 1 atm and found to be varied with temperature between 0.66 and 1 in the temperature range of $500-800^{\circ}C$. A kinetic study of the catalytic reaction was performed in a static reactor at 40 Torr total pressure of $CO_2/CH_4/N_2$ by using a photoacoustic spectroscopy technique. The $CO_2$ photoacoustic signal varying with the concentration of $CO_2$ during the catalytic reaction was recorded as a function of time. Rates of $CO_2$ disappearance in the temperature range of $550-700^{\circ}C$ were obtained from the changes in the $CO_2$ photoacoustic signal at early reaction stage. The plot of ln rate vs. 1/T showed linear lines below and above $610^{\circ}C$. Apparent activation energies were determined to be 10.4 kcal/mol in the temperature range of $550-610^{\circ}C$ and 14.6 kcal/mol in the temperature range of $610-700^{\circ}C$. From the initial rates measured at $640^{\circ}C$ under various partial pressures of $CO_2$ and $CH_4$, the reaction orders were determined to be 0.43 with respect to $CO_2$ and 0.33 with respect to $CH_4$. The kinetic results were compared with those reported previously and used to infer a reaction mechanism for the Ni/$La_2O_3$-catalyzed $CO_2-CH_4$ reaction.