• Prospectives of Industrial Chemistry
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• v.19 no.5
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• pp.1-11
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• 2016

우리나라는 1970년대를 기점으로 하여 급격한 경제성장과 산업기술의 발전이 이루어졌다. 경제성장과 함께 주택의 보급 또한 급격하게 증가하게 되었고, 주택의 보급을 위한 건축자재 및 생활용품의 개발이 급속도로 이루어졌다. 이에 따라 실내에서 사용하는 기구 및 건축재료가 매우 다양해졌으며, 이로 인한 새로운 오염물질의 배출이 급격히 증가하게 되었다. 최근 새로운 기술로 소개되고 있는 촉매 산화법의 경우 제거하려는 대상 실내대기오염물질을 촉매를 이용하여 CO₂나 H₂O 등으로 산화시켜 제거하는 방법이며, 최근 많은 연구가 활발하게 수행되고 있다. 촉매를 이용하는 촉매 산화법은 광촉매 산화법과, 촉매의 성능만을 이용하여 대상물질을 산화하는 촉매산화법으로 구분된다. 광촉매 산화법은 특정 파장에서 반응하는 촉매에 자외선을 조사하여 실내오염물질을 산화제거하는 방법으로, 산화성능이 우수하여 여러 가지 실내오염가스에 적용되고 있으나, 별도의 광원이 필요하며, 포름알데히드 산화 시 CO₂와 H₂O 이외에도 dichloroacetyl chloride (C₂HCl₃O), trichloroethylene (C₂HCl₃), phosgene (COCl₂) 등과 같은 부수적인 2차 유해물질이 발생함에 따라 이를 처리하기 위한 대책이 수반되어야 한다. 반면, 촉매 산화법의 경우 별도의 광원이나 에너지원 없이, 촉매를 이용하여 대기오염물질을 인체에 무해한 물질로 완전 산화시키는 방법으로써, 최근 많은 연구가 수행되어 상온에서 구동 가능한 촉매가 개발되었고, 이의 연구가 활발히 이루어지고 있다. 이에 상온산화촉매기술의 연구동향 및 사례를 확인하고, 향후 상온산화촉매기술이 나아가야 할 방향을 제시하고자 한다. 본 연구는 환경부 환경산업선진화기술개발사업의 지원을 받아 수행되었습니다(2016000140004).

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.05a
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• pp.50-50
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• 2015

양극산화를 통하여 타이타늄 산화물 나노튜뷰를 제조하고 전기화학적 촉매능을 향상시키기 위하여 다양한 방법의 촉매 도핑방법을 소개한다. 특히, 단일(single step) 양극산화법과 전기충격법(potential shock)를 통한 촉매도핑법을 비교하며 장횡비(high aspect ratio)가 높은 나노튜뷰에 균일하고 효율적인 촉매도핑법 및 도핑된 나노튜뷰를 활용한 물분해 실험결과를 소개한다.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.163.2-163.2
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• 2016

타이타늄과 탄소의 비율이 서로 다른 조건에서, 탄소가 도입된 산화타이타늄 (TiO2)을 수열합성법을 이용하여 합성하였다. TEM 이미지를 통하여 일정한 형태의 산화타이타늄이 합성된 것과, XRD 패턴 분석을 통하여 Anatase 형태임을 확인하였다. 본 연구에서는 탄소가 도입된 산화타이타늄을 이종상촉매로 사용하여 일차 및 이차 알코올 산화반응과 메틸렌 블루 분해 실험에 응용하였다.

• Journal of the Korean Applied Science and Technology
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• v.30 no.4
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• pp.649-655
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• 2013

Methanol was directly produced by the partial oxidation of methane with perovskite and mixed oxide catalysts. Perovskite ($ABO_3$) catalysts were prepared by the malic acid method with changing A and B site components. Three-component mixed oxide catalysts that have Mo and Bi as a main component were prepared by the co-precipitation method. Among the perovskite catalysts, $SrCrO_3$ showed the highest methanol selectivity of 11% at $400^{\circ}C$. For the three-component mixed oxide catalysts, there were no remarkable changes in methane conversion. Among the mixed oxide catalysts, Mo-Bi-Cr mixed oxide catalyst showed the highest methanol selectivity of 15.3% at $400^{\circ}C$. The catalytic activity and methanol selectivity of the three-component mixed oxide catalysts were directly proportional to the surface area of the catalysts.

• Applied Chemistry for Engineering
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• v.25 no.3
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• pp.237-241
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• 2014

Benzene is a hazardous air pollutant, classified as carcinogenic to humans, that requires special management. Benzene exists both indoors and outdoors and the control measure of indoor benzene is different from that of outdoor benzene. The removal of indoor benzene needs to be accomplished at low temperatures (normally below $100^{\circ}C$), while outdoor benzene is usually removed at much higher temperature ($300-400^{\circ}C$) by using catalytic oxidation. This review paper summarizes the recent trend in catalytic treatment of airborne benzene, focusing on catalytic oxidation and catalytic ozone oxidation. Particular attention is paid to Mn-based catalysts for low-temperature oxidation of benzene, which are more economical than the other noble-metal catalysts. Various methods are used to generate more efficient Mn-based catalysts for benzene removal. Ozone oxidation is attracting particularly significant attention because it can remove benzene effectively below $100^{\circ}C$, even at room temperature.

• Korean Chemical Engineering Research
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• v.50 no.1
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• pp.41-49
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• 2012

This study was aimed at the development of catalysts for the direct methanol synthesis by partial oxidation of methane. Mo-Bi-V-Al mixed oxide catalysts were prepared and characterized and used in the direct methanol synthesis reaction. The catalysts prepared by the sol-gel method had much larger surface areas than those prepared by the co-precipitation method. The larger the surface area was, the less the methanol selectivity was. The catalysts having larger surface area facilitate the complete oxidation of methane, decreasing the selectivity of methanol. The catalysts prepared by the sol-gel method showed higher methanol selectivity of 13% at $20^{\circ}C$ lower temperature than those prepared by the co-precipitation method. Through XRD analysis, it was revealed that the structures of the catalysts prepared by the two methods were different. In the reaction, methanol selectivity increased and carbon dioxide selectivity decreased with pressure due to the suppression of complete oxidation reaction at a high pressure.

• Korean Chemical Engineering Research
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• v.53 no.3
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• pp.391-396
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• 2015

To investigate the effect of the catalyst synthesis method on the oxidative dehydrogenation (ODH) of nbutenes, $BiFe_{0.65}MoP_{0.1}$ oxide catalysts were prepared with various synthesis methods such as co-precipitation, citric acid method, hydrothermal method, and surfactant templated method. The catalysts were characterized by X-ray Diffraction (XRD), $N_2$ sorption, and $NH_3/1$-butene-temperature programmed desorption ($NH_3/1$-butene-TPD) to correlate with catalytic activity in ODH reaction. Among the catalysts studied here, $BiFe_{0.65}MoP_{0.1}$ oxide catalyst prepared with co-precipitation method marked the highest activity showing 1-butene conversion, 79.5%, butadiene selectivity, 85.1% and yield, 67.7% after reaction for 14 h. From the result of $NH_3$-TPD, the catalytic activity is closely related to the acidity of the $BiFe_{0.65}MoP_{0.1}$-x oxide catalyst and acidity of the $BiFe_{0.65}MoP_{0.1}$ oxde catalyst prepared with co-precipitation method was higher than that of other catalysts. In addition, combined with the 1-butene TPD, the higher catalytic activity is closely related to the amount of weakly adsorbed intermediate (< $200^{\circ}C$) and the desorbing temperature of strongly adsorbed intermediates (> $200^{\circ}C$).

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.228.1-228.1
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• 2010

선택적 CO 산화반응(PrOx)을 위한 Ru이 고분산 담지된 $Ru/{\alpha}-Al_2O_3$ 촉매를 증착-침전법(deposition-precipitation)으로 제조하였다. 용액의 pH와 aging 시간에 따른 Ru 입자의 크기 변화와 분산도의 영향을 살펴보았으며 함침법(impregnation)으로 비교 촉매를 제조하였다. 촉매의 특성분석은 BET, TPR, CO-Chemisorption분석을 수행하여 촉매의 비표면적, 환원특성, 분산도를 알 수 있었다. 특성분석결과, 증착-침전법으로 제조한 $Ru/{\alpha}-Al_2O_3$ 촉매가 함침법으로 제조한 촉매에 비해 분산도가 높았으며, pH별 촉매 제조에서는 pH6.5로 제조한 촉매가 22.06%로 가장 높은 분산도를 보였다. 또한, 담체의 비표면적 영향에 따른 Ru 입자의 분산도를 살펴보기 위해 ${\gamma}-Al_2O_3$와 ${\alpha}-Al_2O_3$ 담체를 적용한 결과, 비표면적이 작은 ${\alpha}-Al_2O_3$ 담체 표면에서 Ru 분산도가 ${\gamma}-Al_2O_3$ 담체에 비해 높았다. 이는 기공이 발달하여 비표면적이 넓은 ${\gamma}-Al_2O_3$ 담체는 소량의 Ru을 고분산 담지 시 담체 표면보다는 기공 내에 담지 되는 양이 많아 실제 반응 시 반응에 참여하는 표면 활성 금속양이 적음을 알 수 있다. 특히, 선택적 산화반응과 같이 표면에서 빠른 반응이 일어나는 경우, 기공 내부의 활성금속이 반응에 참여하기 어려워 반응 활성이 낮음을 PrOx 반응실험을 통해 확인할 수 있었다. PrOx test 조건은 GHSV 250000~60000, 온도는 80~200도, 람다값은 2~4로 성능 비교하여 실험 하였다. PrOx의 성능평가 결과 담체를 ${\alpha}-Al_2O_3$를 사용하여 deposition-precipitation방법으로 제조한 pH6.5 촉매에서 $100{\sim}160^{\circ}C$에서 90%의 가장 높은 CO conversion을 가지고 18%의 선택도를 가졌다.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.3
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• pp.249-256
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• 2006

Catalytic combustion of toluene was investigated on the Cu-Mn oxide catalysts prepared by the impregnation(Imp) and the deposition-precipitation(DP) methods. The mixing of copper and manganese has been found to enhance the activity of catalysts. It is then found that catalytic efficiency of the Cu-Mn oxide catalyst prepared by the DP method on combustion of toluene is much higher than that of the Cu-Mn oxide catalyst prepared by Imp method with the same chemical composition. The catalyst prepared by the deposition-precipitation method observed no change of toluene conversion at time on stream during 10 days and at the addition of water vapor. On the basis of catalyst characterization data, it has been suggested that the catalysts prepared by the DP method showed uniform distribution and smaller particle size on the surface of catalyst and then enhanced reduction capability of catalysts. Therefore, we think that the DP method leads on progressive capacity of catalyst and promotes stability of catalyst. It was also presumed that catalytic conversion of toluene on the Cu-Mn oxide catalyst depends on redox reaction and $Cu_{1.5}Mn_{1.5}O_4$ spinel phase acts as the major active sites of catalyst.

• Journal of the Korean Applied Science and Technology
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• v.34 no.4
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• pp.883-891
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• 2017

For the preferential oxidation of CO contained in the fuel of polymer electrolyte membrane fuel cell (PEMFC), CuO-$CeO_2$ mixed oxide catalysts were prepared by the sol-gel and co-precipitation methods to replace noble metal catalysts. In the catalyst preparation by the sol-gel method, Cu/Ce ratio and hydrolysis ratio were changed. The catalytic activity of the prepared catalysts was compared with the catalytic activity of the noble metal catalyst($Pt/{\gamma}-Al_2O_3$). Among the catalysts prepared with different Cu/Ce ratios, the catalyst whose Cu/Ce ratio was 4:16 showed the highest CO conversion (90%) and selectivity (60%) at $150^{\circ}C$. As the hydrolysis ratio was increased in the catalyst preparation, surface area increased, and catalytic activity also increased. The highest CO conversions with the CuO-$CeO_2$ mixed oxide catalyst prepared by the co-precipitation method and the noble metal catalyst (1wt% $Pt/{\gamma}-Al_2O_3$) were 82 and 81% at $150^{\circ}C$, respectively, whereas the highest CO conversion with the CuO-$CeO_2$ mixed oxide catalyst prepared by the sol-gel method was 90% at the same temperature. This indicates that the catalyst prepared by the sol-gel method shows higher catalytic activity than the catalysts prepared by the co-precipitation method and the noble metal catalyst. From the CO-TPD experiment, it was found that the catalyst having CO desorption peak at a lower temperature ($140^{\circ}C$) revealed higher catalytic activity.