• Transactions of the Korean hydrogen and new energy society
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• v.15 no.3
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• pp.244-249
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• 2004

Pd catalyst have been used in hydrogenation, oxidation, and low temperature combustion reaction. Recently, it has been candidated as a possible reagents in the partial oxidation of methanol reformers of the fuel cell. Pd catalysts, even though it is very precious and expensive, catalytic functioning is good, but it still need to be improved in the matter of durability and low catalytic activity after calcination. In this study, we synthesize the improved Pd catalyst and study their chemical functioning.

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2892-2897
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• 2008

Plasma techniques have been proposed to generate a hydrogen enrich gas to investigate a feasibility of plasma techniques on a fuel reforming, we considered a dry reforming and a partial oxidation with methane in the atmospheric pressure. For these experiments, we employed an arc jet plasma reactor. The effects of input power and oxidizer in each process were investigated by product analysis, including carbon monoxide, hydrogen, ethylene, propane, and acetylene as well as methane and carbon dioxide. In both processes, input electrical power activated the reactions significantly. The increased ratio of the carbon dioxide to methane in the dry reforming doesn't affect to a methane conversion, whereas increased ratio of oxidizer to methane in the partial oxidation was very effective for the reaction. Moreover, for a simultaneous treatment of methane and carbon dioxide, a feasibility of a dry reforming combined with partial oxidation also has been investigated.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.2
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• pp.167-173
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• 2015

Green manure crops are organic materials that can supply organic matter and substitute chemical fertilizer, yet emit methane while being decomposed. Therefore, we experimented with different kinds of Green manure crops and tillage depth in order to decrease the amount of methane emitted when utilizing Green manure crops in paddy soil. The amount of methane emitted during the cultivation period of rice started to increase after transplanting and peaked at 63, and 74 days after transplanting, than decreased to almost none starting from 106 days. According to the kind of Green manure crop, it was highest in barley, then hairy vetch and chemical fertilizer. Depending on the tillage depth, the amount of methane emitted decreased by 22.5% in chemical fertilizer, 12.4% in hairy vetch and 11.7% in barley in 20cm tillage compared to 10cm tillage. The air temperature of methane test period was $30{\sim}40^{\circ}C$, and the soil temperature was more than about $2{\sim}10^{\circ}C$ lower than the air temperature. Due to the irrigation started before transplanting, the oxidation-reduction potential (Eh) of soil was rapidly reduced, and showed negative (-) values. Eh values mostly kept the range of -300~-500 mV during rice cultivation. It rapidly increased 106 days after transplanting. Rice yield the highest in hairy vetch and did not show differences according to tillage depth. Methane emission could be effectively reduced if the paddy soil was tilled by 20 cm during the application of hairy vetch.

• Proceedings of the Korean Nutrition Society Conference
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• 2003.10a
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• pp.155-155
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• 2003

• 한국전기화학회:학술대회논문집
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• 2000.10a
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• pp.55-55
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• 2000

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1998.10a
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• pp.213-215
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• 1998

• Journal of Advanced Marine Engineering and Technology
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• v.35 no.4
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• pp.406-413
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• 2011

Recently the fuel cell has been spotlighted as a technology to reduce greenhouse gases emission from a ship. In this research, internal reforming 500kW solid oxide fuel cell stacks fueled by methane for a ship were developed. Characteristics of power and efficiency depending on the number of cells in the stack, hydrogen conversion ratio, and active area of the cell are evaluated. Also the effects of air and methane supplying conditions on performance are analyzed. As a result, as the number of cells, hydrogen conversion ratio, active area of the cell, or supplied air flow rate increase, the stack power and efficiency increase. When the methane flow rate increases, the power increases. However the efficiency decreases. In addition, the case at the current of 976.4 A, voltage of 529.1 V, with corresponding power of 516.6 kW shows that the efficiency of fuel cell stack is 42.91%.

• Journal of the Korean Chemical Society
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• v.36 no.1
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• pp.147-156
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• 1992

Supported lead oxide catalysts were prepared by using ${\alpha}-,{\beta}-{\gamma}$-alumina, and MgO as a support. Among the supported lead oxide catalysts, MgO-supported catalyst showed the highest $C_2^+$ hydrocarbon selectivity for the methane conversion into $C_2^+$ hydrocarbons, but ${\gamma}$-alumina-supported PbO catalyst gave the highest $CO_2$ selectivity. And ${\alpha}$-alumina-supported catlyst showed the midium activity, whereas ${\beta}$-alumina-supported catalyst gave little activity. These reaction characteristics seemed to be largely dependent on the acticity of lattice oxygens in supported catalysts, which would be influnto be largely dependent on the activity of lattice oxygens in supported catalysts, which would be influenced in the interaction between the supports and lead oxides and the properties of supports. Especially, much higher ration of (002)/(111) peak intensities for PbO phase on MgO support than on the other supports in X-ray diffraction analysis was considered to be ab evidence that methane oxidative coupling of methane might be so-called structure-sensitive reaction, and this seemed to be an example of surface oxide-support interaction (SOSI) in the oxidative coupling reaction.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.5
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• pp.971-980
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• 2000

Mixed methanotrophs (MM) secreting soluble methane monooxygenase(sMMO) were immobilized on celite R-635 to degrade trichloroethylene(TCE) in methanotrophic consortium biofilm reactor(MCBR) system. Further neutralization of celite R-635 was not needed for immobilization because effluent pH was stabilized at neutral after 4 hour washing. It took 130 days to develop biofilm on celite R-635 and the color of the celite changed gradually from white to red. After biofilm developed, influent methane and oxygen were decreased from 2.5~4 and 8~10 ppm to 0.5~1 and 1~2 ppm, respectively, With influent 2 ppm of TCE and 10 hours of retention time, 79.9% of TCE was degraded in the MCBR system.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.231-231
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• 2010

아직까지 국내에서 사용하는 대부분의 에너지는 화석연료에 의존하고 있다. 지하자원에서 나오는 석탄, 석유와 같은 화석연료는 다른 에너지원에 비해 운송이 간편하고 쉽게 이용할 수 있는 장점이 있지만, 환경오염의 문제성과 오일가상승, 자원의양 및 저장장소가 한정되어 있다는 단점을 가지고 있다. 이에 따라 수소와 같은 대체에너지를 이용하여 환경오염을 예방하고 무한히 사용할 수 있는 에너지원을 개발하기 위한 대체 방안들이 연구되고 있다. 폐기물 가스화시 발생되는 합성가스(CO, $CO_2$, $CH_4$, $H_2$) 내 일차로 생성된 일산화탄소는 수증기와 반응함으로써 이산화탄소로 전환이 가능하다. 잔류 메탄은 이산화탄소를 이용하여 개질함으로써 합성가스내 수소농도를 높일 수 있다. 전환된 잔류가스(CO, $CO_2$, $H_2$)내 일산화탄소는 산소를 이용하여 이산화탄소로 산화시킬 수 있으며, 산화된 이산화탄소는 흡착제를 이용하여 제거가 가능하다. 본 연구에서는 실제 가스화시 발생되는 합성가스를 이용하기 위하여, RPF가스화시 발생되는 합성가스를 직접 포집하여 실험을 진행하였다. 합성가스내 소량의 메탄은 니켈촉매를 이용하여 수소로 전화시켰으며, 잔류하는 일산화탄소는 백금촉매, 이산화탄소는 탄산나트륨 흡착제를 이용하여 연속적으로 제거함으로써 순수한 수소를 제공하였다.