• 한국전기화학회:학술대회논문집
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• 2001.06a
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• pp.71-76
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• 2001

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.11a
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• pp.371-374
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• 2008

The performance of several catalysts to decompose the high test peroxide (HTP) was described in this paper. Manganese oxide, Platinum and Iridium were coated on the gamma alumina. The response time of various catalysts was measured with a 50 Newton class thruster. Ir/$Al_2O_3$ that showed the fastest response time at the thruster, failed the reaction when continuous mode test was carried out with the thruster. Pt/$Al_2O_3$ and MnO_2/Al_2O_3$ can be substitutes to decompose the HTP. In addition, for larger thruster, MnO_2/Al_2O_3$ can be a good catalyst because its cost is below 5 % of Pt/$Al_2O_3$.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.49-53
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• 2002

워싱턴주 벤쿠버시 Bonneville 전력소 전주 보관 지역내 PCP와 creosote 오염토양 2g 당 0.020g heme에 0.108g $H_2O$$_2$을 혼합한 산화방법과 0.035g hemoglobin에 0.324g $H_2O$$_2$을 혼합한 산화방법을 비교ㆍ조사하였다. 오염토양에 $^{14}$ C-PCP을 첨가한 다음에 $^{14}$ C의 물질수지를 조사한 결과, 24시간동안 반응 후 $^{14}$ $CO_2$는 heme 과 hemoglobin반응에서는 각각 3.50g와 3.88% 생산되었다. $^{14}$ C 물질수지 분포는 heme 촉매 산화반응에서 용매 상에 43.01% 토양 상에는 46.03%이고, hemoglobin 촉매 산화반응에서는 용매 상에 39.21%와 토양 상에 51.25%로 비슷한 분포를 보였다. 실험실 규모 pan 실험에서 초기 PCP농도 273$\pm$20 mg/kg과 TPH 6379$\pm$45 mg/kg인 오염토양에서 hemoglobin 촉매 산화 반응이 초기반응을 제외하고 7일 이후 반응에서 heme 촉매 산화반응보다 빠르게 분해되었고, 35일 반응 이후 PCP는 10 mg/kg 이하의 값을 나타내었고, TPH도 유사한 결과를 보여 주었다. 그러므로 건조 hemoglobin과 과산화수소에 의한 PCP 오염토양 복원기술은 분해율이 높고 경제성을 가지고 있으므로 기존의 복원공정을 대안으로 제시될 수 있다.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.2
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• pp.184-190
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• 2005

A new VFAs production process from sewage sludge using Fenton's oxidation was investigated. Optimum concentrations of $H_2O_\;and\;Fe^{2+}$ as well as optimum reaction temperature for VFAs production were studied. In the presence of $Fe^{2+}$ as catalyst, the VFAs formation rate increased about 4 times compared to $H_2O_2$ oxidation process without $Fe^{2+}$. Optimum concentrations of $H_2O_2$ and $Fe^{2+}$ were 0.62 M and 0.007 M, respectively. VFAs formation reaction proceeded rapidly within 1 min and VFAs formed degraded partly to acetic acid and $CO_2$, which exhibited series reaction characteristics. Based on the economic aspect, reaction temperature of $25^{\circ}C$ and 10 min of reaction time were thought to be proper reaction conditions. The effect of initial pH in the range of $3{\sim}6.3$ on the VFAs formation was not observed.

• Korean Chemical Engineering Research
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• v.55 no.4
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• pp.567-573
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• 2017

In this work, tungsten oxide ($WO_x$) supported on SBA-15 (mesoporous silica) were prepared and applied for oxidative desulfurization of sulfur compounds in marine diesel containing about 230 ppmw of sulfur concentration. Prepared catalysts were examined by two steps; at first step, oxidation reaction carried out with hydrogen peroxide as oxidant and then the oxidized sulfur compounds were extracted by acetonitrile as solvent. Catalysts were characterized by using X-ray diffraction, X-ray fluorescence, X-ray photoelectron spectroscopy and $N_2$ adsorption-desorption isotherms. Tungsten oxide exists as monoclinic crystal system on SBA-15 and over about 10 wt% of the $WO_x$ loading took the form of multi-layers on SBA-15. The 13 wt% $WO_x$/SBA-15 catalyst exhibite highest activity, achieving about 76.3% sulfur removal in the reaction conditions, such as catalyst amount of 0.1 g, reaction temperature at $90^{\circ}C$, reaction time for 3 h and O/S molar ratio of 10. One time oxidation reaction is enough oxidize the sulfur compounds in marine diesel completely. The repetition experiment of extraction process indicated that sulfur removal could reach 94.4% after 5 times.

• Transactions of the Korean hydrogen and new energy society
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• v.22 no.4
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• pp.415-423
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• 2011

HI decomposition step certainly demand catalytic reaction for efficient production of hydrogen in SI process. Platinum catalyst can apply to HI decomposition reaction as well as hydrogenation or dehydrogenation. Generally, noble metal is used as catalyst which is loaded form for getting high dispersion and wide active area. In this study, Pt was loaded onto zirconia, ceria, alumina, and silica by impregnation method. HI decomposition reaction was carried out under the condition of $450^{\circ}C$, 1atm, and $167.76h^{-1}$ (WHSV) in a fixed bed reactor for measuring catalytic activity. And property of a catalyst was observed by BET, TEM, XRD and chemisoption analysis. On the basis of experimental results, we discussed about conversion of HI according to physical properties of the loaded Pt catalyst onto each support.

• Applied Chemistry for Engineering
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• v.25 no.3
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• pp.312-317
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• 2014

Catalytic combustion of benzene over CuO-$CeO_2$ mixed oxides prepared by co-precipitation method were investigated. The CuO-$CeO_2$ mixed oxides were also prepared using different precipitant and CuO precursor. They were characterized by XRD, BET, XPS and $H_2-TPR$. In the CuO-$CeO_2$ catalysts, characteristic copper oxide peaks were shown at $2{\Theta}=35.5^{\circ}$ and $38.5^{\circ}$ regardless of the precipitant. The Cu0.35 catalyst prepared using $NH_4OH$ as a precipitant revealed the highest activity on the combustion of benzene. In addition, the pretreatment with hydrogen enhanced the catalytic activity and the catalyst reduced at $400^{\circ}C$ showed the highest activity on the combustion of benzene.

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.463-466
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• 2006

직접 알콜 연료전지는 액체인 알콜을 직접 연료전지에 공급하여 연소시킴으로써 높은 효율을 갖는 휴대용전원으로 주목받는 장치이다. 직접 알콜 연료전지에 담지체로 사용되는 탄소 소재는 넓은 표면적과 우수한 전기전도도를 가지고 있다는 장점 있으나 금속 촉매와의 상호작용이 약하여 촉매 활성에 영향을 주지 못한다. 산화물을 담지체로 사용할 경우 이러한 금속-담지체 간의 상호작용으로 인한 촉매활성 증가 및 입자성장 억제의 효과를 기대할 수 있다. 본 연구에서는, 안티몬 도핑된 주석산화물 (Sb-doped SnO2 : ATO nanoparticle)을 직접 메탄올 연료전지용 담지체어 적용하였으며 합성 과정은 다음과 같다. SnC14 5H2O SbC13, NaOH, HCl 수용액 혼합물을 삼구 플라스크에 넣고 $100^{\circ}C$ 온도에서 환류(reflux) 시킨 후 세척 및 건조하여 Air 분위기에서 열처리하였다. 합성된 산화물 수용액에 폴리올 방법으로 합성된 백금 콜로이드를 담지하였으며, 세척과 건조를 통하여 산화물에 담지된 백금 촉매를 촉매를 합성하였다. 촉매의 구조분석을 위해 XRD, TEM을 사용하였으며, 전극촉매로서의 활성을 평가하기 위해 cyclic voltammetry을 평가하였다. 본 연구에서는 백금의 담지량에 따른 Costripping voltammetry특성과 메탄올 및 에탄올 산화 반응 특성에 대하여, 탄소를 담지체로 사용한 Pt/C 촉매와 비교 평가하였다. 알콜 산화반응 평가결과, 주석산화물에 담지한 촉매가 탄소를 담지체로 사용한 촉매보다 우수한 활성을 나타내었으며 활성증가는 메탄올에 비해 에탄올 산화 반응의 경우 크게 증가하였다. 막과 비교해 보았다. $ZrO_2$ 입자는 전도성이며 동시에 친수성을 나타내기 때문에 상용 막에 비하여 함수율 및 수소이온 전도도가 우수하게 나타났다. 복합막의 이러한 물성은 $100^{\circ}C$이상의 고온에서 전해질 막 내의 물 관리를 용이하게 한다. 단위 전지 운전 온도 $130^{\circ}C$, 상대습도 37%의 운전 조건에서도 상당히 우수한 전지 성능을 보임에 따라 고온/저가습 조건에서 상용 Nafion 112 막보다 우수한 막 특성을 나타냄을 확인하였다.소/배후방사능비는 각각 $2.18{\pm}0.03,\;2.56{\pm}0.11,\;3.08{\pm}0.18,\;3.77{\pm}0.17,\;4.70{\pm}0.45$ 그리고 $5.59{\pm}0.40$이었고, $^{67}Ga$-citrate의 경우 2시간, 24시간, 48시간에 $3.06{\pm}0.84,\;4.12{\pm}0.54\;4.55{\pm}0.74 $이었다. 결론 : Transferrin에 $^{99m}Tc$을 이용한 방사성표지가 성공적으로 이루어졌고, $^{99m}Tc$-transferrin의 표지효율은 8시간까지 95% 이상의 안정된 방사성표지효율을 보였다. $^{99m}Tc$-transferrin을 이용한 감염영상을 성공적으로 얻을 수 있었으며, $^{67}Ga$-citrate 영상과 비교하여 더 빠른 시간 안에 우수한 영상을 얻을 수 있었다. 그러므로 $^{99m}Tc$<

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2010.04a
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• pp.150-150
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• 2010

• Korean Chemical Engineering Research
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• v.57 no.5
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• pp.596-605
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• 2019

Proton-conducting perovskite ceramic materials are highly promising for solid electrolytes as well as catalysts at high temperatures. Therefore, they possess an outstanding potential for the membrane reactor in which both reaction and separation occur at a same time. Especially, in the case of hydrogen production catalyst, hydrogen separation, and the membrane reactor coupled with catalyst and separation, extensive results have been reported on the effect of the dopant in the solid electrolytes, temperature, and composition of reactants on the performance. In this review, the recent research trend on the application of proton-conducting ceramic materials to hydrogen production catalyst, hydrogen separation, and membrane reactor is surveyed. Moreover, the potential application and prospect of these materials to the next-generation hydrogen production and separation is discussed.