• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.3
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• pp.83-90
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• 2004

Plasma/catalyst combined reactor was designed to overcome the limits of plasma and catalyst technologies. Optimum reductant and catalyst was selected from screening test. Experiments about the concentrations of reactant and $H_2O$ and the effect of temperature were carried out. Hydrocarbons with double bond such as propylene and so on were more reactive than any other reductants in plasma/catalyst condition. Photocatalyst, especially hombikat >$TiO_2$ with the largest surface area among the catalysts tested, showed the highest DeNOx efficiency in plasma/catalyst reaction. As the concentration of $H_2O$ increased, the removal of NO was enhanced. The increased concentration of >$O_2$ promoted the reaction of NO which was oxidized to$NO_2$.

• Applied Chemistry for Engineering
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• v.25 no.5
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• pp.531-537
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• 2014

A catalytic plasma reactor was employed for the oxidation of isopropyl alcohol (IPA) classified as a volatile organic compound (VOC). Copper oxide (Cu : 0.5% (w/w)) supported on a multichannel porous ceramic consisting of ${\alpha}-Al_2O_3$ was used as a catalyst, which was directly exposed to the plasma created in it. The effects of discharge voltage and reaction temperature on the concentrations of IPA and its byproducts were examined to understand the behavior of the catalytic plasma reactor. Without thermal insulation, the reactor temperature increased up to $120^{\circ}C$ at an applied voltage of 17 kV (discharge power : 28 W), and the IPA at a flow rate of $1L\;min^{-1}$ ($O_2$ : 10% (v/v); IPA : 1000 ppm) was completely removed. At temperatures below $120^{\circ}C$, however, besides the desirable product $CO_2$, several unwanted byproducts such as acetone, formaldehyde and CO were also formed from IPA. On the other hand, when the reactor was thermally insulated, the plasma discharge increased the temperature up to $265^{\circ}C$ under the same condition and most of IPA was oxidized to $CO_2$. Without loading CuO on the ceramic support, the plasma discharge in the thermally insulated reactor produced nearly equal amounts of $CO_2$ and CO. On comparison, with the catalyst alone (temperature : $265^{\circ}C$), more than 70% of the removed IPA was simply converted into another type of VOC (acetone), indicating that the catalyst assisted by the plasma is more effective in the oxidation of IPA than that of the catalyst-alone process.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.143-144
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• 2003

최근 들어 플라즈마 촉매 복합공정을 이용하여 NOx를 제거시키기 위한 연구가 활발히 이루어지고 있다. 저온 플라즈마 공정중 하나인 DBD (Dielectric barrier discharge) 공정 내에서 NO는 NO$_2$로 매우 효과적으로 전환된다. 촉매공정의 경우 NO보다 NO$_2$가 주입되는 경우 NOx 제거 효율이 높고 촉매의 피독 현상도 줄어들게 된다. 따라서 DBD를 이용하여 NO의 전환율을 높일 수 있다면 플라즈마 촉매 복합공정의 NOx 제거 효율은 매우 높아진다. DBD 반응기 내에서 NO를 NO2로 전환시키는데 가장 중요한 역할을 하는 것 중 하나는 오존 (O$_3$)이다. (중략)

• Applied Chemistry for Engineering
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• v.16 no.3
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• pp.413-421
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• 2005

This study focused on the decomposition of toluene in a plasma-photocatalytic hybrid system. Hexagonally packed meso-structured Mn-titanosilicates (Mn-Ti-MCM-41), as the photocatalysts, have been prepared by the hydrothermal method. The physical properties of the photocatalysts were characterized using XRD, XPS, TEM, BET/ICP, and $NH_3$/Toluene-TPD. Experiments were carried out at the applied voltage of 9.0 kV and at room temperature of $20^{\circ}C$. In the plasma only system, the activity of the toluene decomposition was higher than that in the photocatalytic system. However, the amount of by-products, such as phenol, $C_2{\sim}C_4$ alkene, was also increased in the plasma only system. However, the by-products decreased remarkably in a plasma-photocatalytic hybrid system. When Mn5mol%-Ti-MCM-41 was used as a photocatalyst in a plasma-photocatalytic hybrid system, the $CO_2$ selectivity in products was increased dramatically compared to other catalysts. It was confirmed that a plasma-photocatalytic hybrid system was better for toluene decomposition compared to photocatalytic and plasma only systems.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2002.05a
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• pp.197-201
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• 2002

최근 산업의 발달과 더불어 대기오염 물질이 증가되는 반면에 쾌적한 환경에 대한 욕구로 환경 규제기준이 강화되고 있다. 특히 화석연료를 연소시킬 때 배출되는 질소산화물은 산성비, 호흡기질환, 도시의 스모그 현상 등을 일으키는 주범으로 1999년부터 배출 규제치가 강화되었다. 따라서 경제적이고 효율적인 유해 배가스 처리기술들의 개발 필요성이 대두되고 있다.(중략)

• Applied Chemistry for Engineering
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• v.28 no.2
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• pp.193-197
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• 2017

In this study, we report on the catalyst process installed in conjunction with a wet plasma electrostatic precipitator to remove the oil mist and fine dust emitted from large-size grill restaurants. The multi-stage catalyst module reduced odor through catalytic reaction of acetaldehyde on catalysts even at an ambient temperature with ozone as an oxidant readily produced in a wet plasma electrostatic precipitator. Two types of manganese-based catalysts, $Mn_2O_3$ and $CuMnO_x$ were fabricated by extrusion molding for structured catalysts in practical applications, and the optimum conditions for high removal efficiencies of acetaldehyde and ozone were determined. When two optimized catalysts were applied in a two-stage catalyst module, the removal efficiency of acetaldehyde and ozone were ${\geq}85%$ and 100% respectively at the space velocity of $10,000h^{-1}$ and the reaction temperature of $100^{\circ}C$.