• Transactions of the Korean hydrogen and new energy society
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• v.19 no.6
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• pp.520-528
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• 2008

2-step methane reforming, consisting of syn-gas production and water splitting step, was carried out over Cu-ferrite/$ZrO_2$. To improve the reactivity over Cu-ferrite/$ZrO_2$ presenting low reactivity in 2-step methane reforming, the addition of Ni was considered. As the results, the added Ni to Cu-ferrite/$ZrO_2$ improved the reactivity in syn-gas production step. However, (Cu, Ni) ferrite/$ZrO_2$ showed carbon deposition in syn-gas production step when an excess Ni was added. Furthermore, (Cu, Ni) ferrite/$ZrO_2$ showed the high durability without the deactivation of the medium during repeated ten cycles, although it showed more deposited carbon than the medium without Ni.

• Transactions of the Korean hydrogen and new energy society
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• v.25 no.4
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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.

• Membrane Journal
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• v.31 no.2
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• pp.133-144
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• 2021

Alkaline water electrolysis system is the oldest technology among various hydrogen production processes to produce green hydrogen with the least amount of greenhouse gas generated. Alkaline water electrolysis (AWE) system is used in alkaline atmosphere condition. In comparison to polymer electrolyte membrane water electrolysis (PEMWE), this system can utilize stable transition metals such as nickel, cobalt, and silver, as electrode catalysts. AWE is relatively inexpensive, and can easily be scaled up to large scale. The system is a mature technology, as it has been in operation since the beginning of the 20th century in MW-scale for hydrogen generation, and there are currently more than 20 commercial manufacturers. In this review, the basic principles of AWE, along with catalysts, electrodes, and diaphragm membranes, are summarized. Particularly, the research and development trends of the diaphragm membrane unit, which is the core component of an AWE, are discussed in detail.

• New & Renewable Energy
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• v.4 no.2
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• pp.39-44
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• 2008

Partial oxidation of methane was carried out by ceria-promoted Ni-substituted hydrotalcite-derived catalysts ($Ce_xNi_3$-HTlc ; x=$0.3{\sim}1.2$) in a fixed-bed reactor. The Ce/Ni ratio of 0.3/3 in the catalyst showed the best catalytic activity but the Ce/Ni ratio became higher above 0.3/3, the catalyst became less active in short-term tests. No ceria promoted catalyst was started to decrease $CH_4$ conversion after 20 h but the Ce/Ni ratio 0.3/3 catalyst was kept its stability in long-term tests.

• Journal of the Korean Chemical Society
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• v.54 no.1
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• pp.27-37
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• 2010

The reaction of 1,1'-bis(dimethylhydrosilyl)ferrocene with alkynes in the presence of a catalytic amount of ($C_2H_4$)Pt$(PPh_3)_2$ leads to the acyclic mixture of monohydrosilylated and/or dihydrosilylated compounds. But the analogous reactions in the presence of Ni$(PEt_3)_4$ catalyst yield monohydrosilylated compounds or dihydrosilylated products. The monohydrosilylated products were generated from the reactions of alkenes with the silylated ferrocene using nickel catalyst.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2008.04a
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• pp.123-126
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• 2008

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.186-189
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• 2008

Solar simulator를 이용한 메탄의 수증기 개질은 집광된 태양에너지를 이용하기 위한 목적으로 수행되었다. 본 연구에서는 이와 같은 태양열에너지의 화학적 축열을 실시하기 위해 Solar Simulator를 이용한 메탄의 수증기 개질을 연구하였다. 태양열 모사 램프로 1.2kW급 Xenon-arc lamp를 사용하였다. 반응기는 앞면의 Quartz Window와 촉매지지층으로 구성되어 있다. 램프의 빛은 Quartz Window를 통하여 촉매층에 직접적으로 방사되고, 방사된 빛으로 촉매지지층에서 흡열반응이 일어난다.메탄의 수증기개질 반응은 고온에서 일어나기 때문에 촉매지지체를 열에 강한 SiC로 만들어진 Ceramic foam을 사용하였다. 이 촉매지지체에 촉매를 Wash-coat하여 사용하였으며, 담지된 촉매는 Ni을 활성성분으로 하는 ICI 46-6을 사용하였다. 반응기는 318 SUS 재질로 제작되었으며, 반응기 외부는 Insulation을 하여 열손실을 감소시켰다. 실험은 온도와 공간속도에 따른 Solar Steam reforming의 반응특성을 분석하였다.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1306-1307
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• 2011

Recently, the small scale photovoltaic (PV) electronic devices are drawing attention as the upcoming PV generation system. The PV system is commonly used in small scale PV applications such as LED lighting and cell phone. This paper proposes photovoltaic output sensorless (POS) maximum power point tracking (MPPT) control for a small scale charging system of PV-nickel metal hydride battery using field-programmable gate array (FPGA) controller. A converter is connected to a small scale PV cell and battery, and performs the POS MPPT at the battery terminal current instead of being at the PV cell output voltage and current. The FPGA controller and converter operate based on POS MPPT method. The experimental results show that the nickel metal hydride battery is charged by the maximum PV output power.

• 한국연소학회:학술대회논문집
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• 2007.05a
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• pp.37-44
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• 2007

A nickel foam, one of metal foams was seleced as a catalyst support instead of conventional ceramic materials. $Al_2O_3$ was coated on the surface of nickel foam to increase the surface area. $Al_2O_3$ coating process was based on sol-gel process. SEM image was obtained and $Al_2O_3$ coverage was confirmed. Combustion experiments were carried out using SUS combustor and $H_2$/air mixture. Temperatures were measured with different equivalence ratios and $H_2$ flow rates. $H_2$ conversion rates were calculated by the analysis of product gas using gas chromatography. Catalytic combustion of $H_2$ was complete and stable with Pt/$Al_2O_3$ coated nickel foam and influences of water vapor were confirmed during the beginning of combustion.

• Proceedings of the Materials Research Society of Korea Conference
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• 2010.05a
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• pp.50.2-50.2
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• 2010

니켈기 초내열합금 Inconel 617은 수소생산용 초고온 가스 냉각로의 열 교환기와 고온 가스관 등의 고온 배관용 후보재료로써, Cr, Mo, 와 W등의 첨가물이 함유된 고용 강화된 합금으로, 우수한 고온 강도, 크립 저항성, 내부식성 및 내산화성을 가지고 있는 것으로 알려져 있다. 본 연구에서는 결정립 미세화가 고온열화에 의해 입계를 따라 형성되는 internal oxide에 미치는 영향에 대해 평가하였고, 이러한 internal oxide가 인장응력 하에서 크렉 형성 및 전파에 미치는 영향을 평가하기 위하여 3-point bending test를 수행하였다. 미세한 결정립을 가지는 Inconel 617은 냉간압연 후 재결정을 통해 확보하였으며, as-received(AR)과 grain-refined(GR) Inconel 617은 $950^{\circ}C$에서 2000시간 동안 He분위기 하에서 열화시험을 수행하였다. AR과 GR에 형성된 internal oxide은 깊이와 분포 등의 뚜렷한 차이를 보였으며, 이러한 차이로 인해 인장응력 하에서 크렉 전파의 큰 차이를 나타내었다.