• Bulletin of the Korean Chemical Society
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• 제28권12호
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• pp.2288-2292
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• 2007

The catalytic activities of nickel-based catalysts were estimated for oxidizing acetaldehyde of VOCs exhausted from industrial facilities. The catalysts were prepared by sol-gel methods of SiO2 and SiO2-TiO2 as a xerogel followed by impregnating Al2O3 powder with the nickel nitrate precursor. The crystalline structure and catalytic properties for the catalysts were investigated by use of BET surface area, X-ray diffraction (XRD), Xray photoelectron spectroscopy (XPS) and temperature programmed reduction (TPR) techniques. These results show that nickel oxide is transformed to NiAl2O4 spinel structure at the calcination temperature of 400 °C in response to the steps with after- and co-impregnation of Al2O3 powder in sol-gel process. The NiAl2O4 could suppress the oxidation reaction of acetaldehyde by catalysts. The NiO is better dispersed on SiO2-TiO2/Al2O3 support than SiO2/Al2O3 and SiO2-TiO2-Al2O3 supports. From the testing results of catalytic activities for oxidation of acetaldehyde, Catalysts showed a big difference in conversion efficiencies with the way of the preparation of catalysts and the loading weight of nickel. The catalyst of 8 wt.% Ni/TiO2-SiO2/Al2O3 showed the best conversion efficiency on acetaldehyde oxidation with 100% conversion efficiency at 350 °C.

• Bulletin of the Korean Chemical Society
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• 제28권8호
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• pp.1273-1279
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• 2007

The NiSO4 supported on Fe2O3 catalysts were prepared by the impregnation method. No diffraction line of nickel sulfate was observed up to 30 wt %, indicating good dispersion of nickel sulfate on the surface of Fe2O3. The addition of nickel sulfate to Fe2O3 shifted the phase transition of Fe2O3 (from amorphous to hematite) to higher temperatures because of the interaction between nickel sulfate and Fe2O3. 20-NiSO4/Fe2O3 containing 20 wt % of NiSO4 and calcined at 500 oC exhibited a maximum catalytic activity for ethylene dimerization. The initial product of ethylene dimerization was found to be 1-butene and the initially produced 1-butene was also isomerized to 2-butene during the reaction. The catalytic activities were correlated with the acidity of catalysts measured by the ammonia chemisorption method.

• 한국수소및신에너지학회논문집
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• 제30권3호
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• pp.209-219
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• 2019

Methanol is a liquid fuel which could also be produced from renewable energy sources and has appreciably high energy density. In this work, we investigated the application of $Ce_{0.9}Gd_{0.1}O_{2-x}$ supported Cu and Ni catalysts for hydrogen production via methanol steam reforming. Catalysts were synthesized by solution combustion synthesis. The prepared catalysts with various active materials and Cu loading amounts were tested in a reactor at $200-300^{\circ}C$, 0-5 barg range and steam to methanol molar ratio was 1.5. The catalytic properties of Cu and Ni were compared, and the catalytic performance was shown to depend on the amounts of metal loading and operating conditions such as reaction temperature and pressure.

• 한국응용과학기술학회지
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• 제21권1호
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• pp.89-96
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• 2004

The effect of La promoter on the carbon deposition and catalytic activity in the synthesis gas production with supported Ni catalysts was investigated. Active component was Ni and support was $CeO_2$ and the promoter used was La. The reaction was carried out in a fixed bed reactor at 1 atm and $650{\sim}800^{\circ}C$. The catalysts were prepared by two methods, the impregnation method and urea method. The catalysts prepared by the urea method showed 10 times higher surface area than those of prepared by the impregnation method. By the introduction of La promoter in the catalyst system, carbon deposition was remarkably reduced from 16% to 2%. It appears that the promoter facilitates the formation of a stable fluoride-type phase, which reduces the carbon deposition. The best catalytic activity and CO and $H_2$ selectivities were obtained with 2.5wt% $Ni/Ce(La)O_x$ catalyst at $750^{\circ}C$, giving 90% methane conversion, 93 and.80% of CO and $H_2$ selectivities, respectively.

• 공업화학
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• 제9권7호
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• pp.1070-1078
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• 1998

농축상을 포함한 다원 반응계의 Gibbs Free Energy 최소화 계산을 수행하여 이산화탄소 개질반응에 대한 열역학적 분석을 수행하였으며, $Al_2O_3$, $La_2O_3$, ZSM-5, MCM-41, 그리고 KIT-1의 담체에 담지된 니켈 촉매와 상업용 개질 촉매 ICI 46-1상에서 이산화탄소에 의한 메탄의 개질 반응 실험을 수행하였다. 메탄의 이산화탄소에 의한 개질반응 열역학 계산은 $CH_4$, $CO_2$, CO, $H_2$, $H_2O$, C계에서 수행하는 것이 바람직하였고, 수증기나 산소의 첨가 효과는 이산화탄소의 개질 반응 기여도를 감소시키는 것으로 예상되었다. Ni/ZSM-5, Ni/MCM-41, Ni/KIT-1등 실리케이트 계열의 분자체 담체에 니켈을 담지시킨 촉매가 메탄과 이산화탄소의 전화율이 우수하며, 일산화탄소 수율도 높은 것을 알 수 있었다. 이산화탄소 개질 반응에 대한 코크의 침적은 칼슘 산화물을 첨가함으로써 감소되었으며, 10% Ni과 3% Ca를 담지시킨 Ni/Ca/KIT-1 촉매가 20시간 동안 $650^{\circ}C$ 이상에서 평형 전화율에 근접한 이산화탄소와 메탄의 전화율을 나타냄이 확인되었다. 또한 상대적으로 높은 공간 속도에도 우수한 활성을 나타내었다.

• 한국수소및신에너지학회논문집
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• 제25권4호
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• pp.344-354
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• 2014

Activated charcoal supported nickel molybdenum carbide (carburized Ni-Mo/AC) catalysts were prepared by wet-impregnation followed by temperature-programmed carburization using 20% $CH_4/H_2$ gas. The effects of pH and initial Ni/Mo mole ratio during wet-impregnation step on the characteristics of the carburized Ni-Mo/AC catalysts were investigated using ICP, XRD, XPS, BET and $CO_2$-TPD techniques, and correlated with the catalytic activity of the carburized Ni-Mo/AC in methane dry reforming reaction. Comparison of the results of methane dry reforming reaction kinetics with the results of characterization of the carburized Ni-Mo/AC catalyst showed that the catalytic activity in methane dry reforming reaction was higher at higher initial Ni/Mo mole ratio or at lower pH(3~natural value). This phenomenon was related to the crystal size of metallic Ni in the carburized Ni-Mo/AC catalyst.

• Bulletin of the Korean Chemical Society
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• 제22권12호
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• pp.1303-1308
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• 2001

A series of catalysts, NiSO4/TiO2, for ethylene dimerization was prepared by the impregnation method using aqueous solution of nickel sulfate. On the basis of the results obtained from X-ray diffraction, the addition of NiSO4 shifted the transition of TiO2 from the anatase to the rutile phase toward higher temperatures due to the interaction between NiSO4 and TiO2. Nickel sulfate supported on titania was found to be very active even at room temperature. The high catalytic activity of NiSO4/TiO2 closely correlated with the increase of acidity and acid strength due to the addition of NiSO4. It is suggested that the active sites responsible for ethylene dimerization consist of low valent nickel, Ni+, with an acid.

• 한국수소및신에너지학회논문집
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• 제14권1호
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• pp.69-80
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• 2003

Nickel catalyst has been used for natural gas reforming with carbon dioxide, In this study, catalyst support used was HY zeolite. The optimum loading of Ni in the catalysts was 13 wt%. The effect of promoters, such as Mg, Mn, and K, was also studied. The addition of promoters to Ni catalyst improved the stability of catalysts and carbon deposition on Ni catalyst was suppressed. The reforming reactivity of promoter-added Ni catalyst was higher than that of Ni catalyst without any promoters. SEM, XRD, BET, TGA and FTIR tests were tried to characterize the catalyst structure before and after reaction.

• Bulletin of the Korean Chemical Society
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• 제26권10호
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• pp.1512-1514
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• 2005

Catalytic properties of Ni-Zr$O_2$ catalysts prepared by coprecipitation have been studied for the gas-phase hydrogenation of 1,3-butadiene to butenes. The coprecipitation method led to the solid solution of Ni-Zr$O_2$, which contains highly resistant Ni species to thermal reduction with H2. Nickel species of the solid solution were highly dispersed in the ZrO2 lattice, so that the reduced catalysts were selective for hydrogenation of 1,3-butadiene to butenes (99.9%) even in the presence of 1-butene.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.166-166
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• 2013

Mesoporous $SiO_2$-supported Ni catalysts (Ni/$SiO_2$ and Ni/$TiO_2$/$SiO_2$) were fabricated by atomic layer deposition (ALD), and their catalytic activity and stability were investigated in carbon dioxide reforming of methane (CRM) reaction at $800^{\circ}C$ The Ni/$SiO_2$ catalysts showed high stability as a result of confinement of Ni particles with a mean size of ~10 nm within the pores of $SiO_2$ support. Besides, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and transmission electron microscopy (TEM) results showed that the Ni nanoparticles were partially buried inside the $SiO_2$ support. The strong interaction between Ni and the $SiO_2$ support could also be advantageous for long-term stability of the catalyst. In case of the Ni/$TiO_2$/$SiO_2$ catalyst, it was found that the catalytic activity of 10 nm-sized Ni nanoparticles was not much influenced by $TiO_2$ addition.