• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.04a
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• pp.293-294
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• 2002

화석연료의 연소로부터 발생되는 질소산화물은 산성비, 광화학스모그 및 오존층 파괴에 관여하는 환경오염물질로서 대기오염의 주범이 되고 있다. 연소 후 배기가스 중의 질소산화물 제어를 위한 선택적 촉매환인공정(Selective Catalytic Reduction: SCR)은 안정적이며 고효율 설계가 가능하여 범용적으로 사용되고 있는 기술이다. SCR 공정은 최초 미국에서 개발되었으나 일본과 독일에서 발전시켜왔으며 국내에서도 공정의 핵심기술인 촉매에 대한 다양한 연구를 수행하여 일부에서는 상용화 수준에 이르고 있다. (중략)

• Proceedings of the Materials Research Society of Korea Conference
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• 1992.05a
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• pp.144-144
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• 1992

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1997.10a
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• pp.54-58
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• 1997

• Applied Chemistry for Engineering
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• v.9 no.1
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• pp.101-106
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• 1998

Two types of CoMo/zeolite as well as $NiMo/{\gamma}-Al_2O_3$ were prepared and their activities and selectivities of low-temperature dibenzothiophene(DBT) hydrodesulfurization(HDS) were studied in high pressure fixed bed reactor. The HDS activities of CoMo/zeolites were higher than that of $NiMo/{\gamma}-Al_2O_3$ at temperatures below $225^{\circ}C$ while they were lower than that of $NiMo/{\gamma}-Al_2O_3$ at temperatures higher than $275^{\circ}C$. The main products from $NiMo/{\gamma}-Al_2O_3$ were biphenyl and cyclohexylbenzene. The product distribution of CoMo/zeolite catalysts was different from that of $NiMo/{\gamma}-Al_2O_3$. It is speculated that DBT is converted to alkylcyclohexane over zeolite based catalysts through both alkylation and hydrogenation reactions. The crystal structure of molybdenum was $MoO_3$ in fresh zeolite support while mixtures of $MoO_3$ and $MoS_2$ were observed in the aged catalyst.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.97.1-97.1
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• 2011

저온에서 양이온 고분자막을 사용하는 고분자 연료전지의 경우 뛰어난 성능과 다양한 응용분야로 인해 많은 연구와 실증이 이루어지고 있지만 공기극에서의 느린 산소 환원반응으로 인해 백금과 같은 귀금속의 사용이 불가피하고 백금의 제한된 매장량과 높은 가격으로 인해 상용화가 늦어지고 있다. 그래서 많은 연구자들이 합금 촉매 또는 비귀금속 촉매를 이용한 전극 개발에 집중하고 있다. 알칼리 분위기에서 저가의 전이 금속들이 백금과 비슷한 활성을 보이고 고체 음이온 교환막이 개발됨에 따라 최근 알칼리 연료전지가 다시금 큰 주목을 받고 있다. 그러나 고분자 연료전지와는 달리 아직 촉매나 전해질막, 이오노머의 특성 및 메커니즘에 관해 별로 알려진 것이 없다. 본 연구에서는 직접 개발한 세공충진막 형태의 탄화수소계의 음이온 교환막과 비귀금속 공기극 촉매를 이용하여 막전극접합체(MEA)를 개발하였고 촉매 및 이오노머 함량과 같은 전극 조성, 막전극접합체의 제조 및 체결, 가습이나 가스조성 등의 단위전지 운전조건과 같은 다양한 변수에 대해에 최적 조건을 도출하고자 하였다. 공기극 촉매는 Cu-Fe/C를 이용한 상용 촉매를 이용하였고 이오노머의 경우는 탄화수소계의 상용 제품을 사용하였으며 음이온 교환막에 전극층을 형성하기 위해서는 스프레이 공정을 이용하였다. 단위전지를 통해 성능을 확인하였고 임피던스 및 CV를 통해 전기화학적인 특성을 규명하였다. 조건의 최적화를 통해 상당한 성능 향상을 이루었으나 추가적인 성능 향상 및 내구성 확보 등에 대해 계속적인 실험을 진행할 예정이다.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.4
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• pp.444-451
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• 2007

Catalytic oxidation characteristics of benzene as a VOC was investigated using a fixed bed reactor system over transition $metals/\gamma-Al_2O_3$ catalysts. As transition metals, eight metals including copper, nickel, manganese, iron etc. were adopted. The parametric tests were conducted at the reaction temperature range of $200\sim500^{\circ}C$, benzene concentration of $1,000\sim3,000$ ppm, and space velocity range of $5,000\sim60,000\;hr^{-l}$. The property analyses such as BET, SEM, XRD and the conversions of catalytic oxidation of VOC were examined. The experimental results showed that the conversion was increased with decreasing VOC concentration and space velocity. It was also found that $Cu/\gamma-Al_2O_3$ catalyst calcinated at $500^{\circ}C$ showed the highest activity for the oxidation of benzene and 15% metal loading was the optimum impregnation level.

• Applied Chemistry for Engineering
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• v.1 no.2
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• pp.240-248
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• 1990

The catalytic activity and selectivity of metal loaded H-mordenite for transalkylation of $C_9$ aromatics were studied in a continuous flow fixed bed reactor under high pressure. Nickel loaded H-mordenite(T-Ni) catalyst showed high activity and slow decay of activity. Molybdenum and nickel loaded H-mordenite(T-NiMo) catalyst also showed high activity and suppressed coking of hydrocarbons. The selectivity of xylene for T-Ni and T-NiMo catalysts decreased with temperature, but that for T catalyst(commercial grade) monotonically increased with temperature within the experimental range. The performance of T-Ni and T-NiMo catalysts was better than that of T catalyst in terms of initial activity and its decay. The addition of Mo improved slightly stability of T-Ni catalyst.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.2
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• pp.209-213
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• 2016

The characteristics of fluidization in a centrifugal fluidized bed with a 184 mm inner diameter, 50 mm width of the gas distributor was observed by photographs and experimental works using Cu-ZSM-5 zeolite catalysts with a mean diameter of $26{\mu}m$ and $32{\mu}m$ as bed materials at a rotor at 400rpm and 600rpm. Under these experimental ranges, the experimental results clearly showed the effects of the number of rotation of the rotor on the behavior of bubbles in the centrifugal fluidized bed. As the number of rotations of the rotor increased, the gas velocity at which bubbles begin to be formed also increased but the diameter of the bubbles decreased. In addition, the size of the bubbles in the centrifugal fluidized bed were relatively smaller than those in the conventional bubbling fluidized bed.

• Journal of the Microelectronics and Packaging Society
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• v.29 no.1
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• pp.61-66
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• 2022

This study is to increase the surface area and maximize the effect of the catalyst by coating a nanometersized metal catalyst material on the anode layer using atomic layer deposition (ALD) technology. ALD process is known to produce uniform films with well-controlled thickness at the atomic level on substrates. We measured the performance by coating metals (Ni) on Ni/YSZ, which is the most widely known anode material for solid oxide fuel cells. ALD coatings began to show a decrease in cell performance over 3 nm coatings.

• Transactions on Semiconductor Engineering
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• v.1 no.1
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• pp.9-13
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• 2023

An AlGaN/GaN heterojunction-based hydrogen sensor with SnO₂ nanoparticles/Pd catalyst layer was fabricated for room-temperature hydrogen detection. The fabricated sensor exhibited unstable drift in standby current when it was operated at room temperature. The instability in the sensing signal was dramatically improved when the sensor was operated under UV illumination.