• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.1255-1260
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• 2004

Decomposition of ozone at room temperature was investigated comparatively with commercial monolithic ozone decomposition catalyst (ODC, $MnO_2$) and monolithic photo catalyst ($TiO_2$). The effects of residence time, UV (ultraviolet) light dependence and ozone concentration on the conversion was presented. UV ray was irradiated using BLB (black light blue) lamp ($315{\sim}400$ nm), supplied with a constant intensity in the reactor. The concentration of ozone in the square-shape reactor can be controlled by combining the DBD (dielectric barrier discharge) reactor with an AC high voltage supply system. The catalytic performance, in presence of UV irradiation did not show significant changes for $MnO_2$ catalyst. $TiO_2$ catalyst was the different case, which showed higher decomposition activity in presence of UV irradiation. Deactivation of catalyst detected by real-time ozone monitor for 120 hours with a constant inlet ozone concentration.

• 산업기술연구
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• 제26권A호
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• pp.199-205
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• 2006

Ozone alone and catalytic ozone processes were introduced for treatment of humic acid, which is representative refractory organic compound. The treatment efficiencies of humic acid in each process were analyzed in pH variation, DOC removal, and $UV_{254}$ decrease. Mn loaded GAC catalyst was prepared by loading potassium permanganate onto the granular activated carbon surface. BCM-GAC and BCM-Silica gel catalyst were prepared by BCM. $UV_{254}$ decrease in all processes was comparatively high with efficiency over 87%. DOC removal in ozone/GAC process was the highest with 78%, and removal rates for other processes followed the order ozone/BCM-GAC(62%) > ozone/BCM-silica gel(45%) > ozone/silica gel(43%) > ozone/Mn Loaded GAC(42%) > ozone alone(37%).

• 전기전자학회논문지
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• 제23권2호
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• pp.431-437
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• 2019

논문은 유전체 볼 충진 배리어 방전 리액터를 이용하여 오존 생성 및 TCE 분해 특성에 대하여 논하였다. 오존 발생량은 $Al_2O_3$ 또는 $TiO_2$ 유전체 볼을 충진한 경우가 유전체 볼을 충진하지 않은 배리어 방전리액터에 비하여 크게 증가됨을 보였으며, 이러한 방전구조는 오존 생성량을 증가시키기에 적절한 것으로 판단되었다. 또한, TCE 분해효율과 COx 전환율은 $MnO_2$ 충진 방전리액터를 사용한 경우가 높았으며, 이것은 방전공간에 위치한 촉매 표면에서 오존 분해에 따른 화학반응에 기인된 것으로 파악되었다. 촉매 표면 화학반응을 파악하기 위하여 Al2O3 유전체 볼 충진 방전리액터와 촉매 리액터를 직렬로 배치하여 TCE 분해 효율이 100[%]에 도달하였음을 확인하였으며, $MnO_2$ 촉매는 오존 분해에 매우 좋은 재료이며, 이러한 오존 분해 촉매 반응을 이용하여 TCE와 같은 VOCs 분해에 유용하게 활용될 것으로 사료된다.

• 한국전기전자재료학회논문지
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• 제34권1호
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• pp.56-62
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• 2021

In this study, we created a DBD plasma device and a MnO2 catalyst mesh filter for evaluating ozone reduction of devices via the catalyst method. The DBD plasma device was manufactured by applying Ag paste to soda lime glass via the screen-printing method. The MnO2 catalyst mesh filter was manufactured by mixing MnO2 powder with binder with a 10% difference in concentration from 10% to 50% and then applying it using the dip-coating method. Finally, we sintered a MnO2 catalyst mesh filter in an electric furnace. We evaluated the characteristics of ozone generation according to the Ar gas flow of DBD plasma devices, the opening ratio, and ozone reduction performance of the MnO2 catalyst filters. Ozone reduction performance was approximately 20.4% at MnO2 10 wt%, 37.8% at MnO2 30 wt% and 50% at MnO2 50 wt%.

• 공업화학
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• 제24권2호
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• pp.161-164
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• 2013

본 연구에서는, 폐건전지로부터 회수된 특정 성분들을 이용하여 오존분해 촉매로서의 적용성을 평가하였다. 폐건전지에서 축출된 성분 중, Mn의 함량이 오존분해 반응에 주요 인자임을 보였다. 또한, Zn 함량에 따라 deactivation rate와 높은 상관성을 나타냈으며, K 함량은 오존분해 반응과 상관성이 없음을 나타냈다. 그리고 $TiO_2$를 첨가하여 제조한 촉매는 Mn 함량의 감소로 인한 효율 저하를 나타냈으며, Mn 구조상의 특징은 오존분해 반응과 상관성이 없음을 나타냈다.

• 전기학회논문지
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• 제59권5호
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• pp.932-938
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• 2010

This paper proposed the effective treatment method for organic substances using the barrier discharge plasma process and catalytic chemical reaction followed from ozone decomposition. The decomposition by the plasma process of organic substances such as trichloroethylene, methyl alcohol, acetone, and dichloromethane carried out, and ozone is generated effectively at the same time. By passing through catalysts, ozone easily decomposed and further decomposed organic substances. And, 2-dimensional distribution of ozone using the optical measurement method is performed to identify the catalytic surface chemical reaction. In addition, CO is easily oxidized into $CO_2$ by this chemical reaction, which might be induced oxygen atom radicals formed at the surface of catalyst from ozone decomposition.

• 대한기계학회논문집B
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• 제27권4호
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• pp.524-533
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• 2003

DBD(Dielectric Barrier Discharge) plasma in air is well established for the production of large quantities of ozone and is more recently being applied to aftertreatment processes for HAPs(Hazardous Air Pollutants). Aim of this work is to determine design and operating parameters of a hybrid air cleaning system. DBD and ESP(Electrostatic Precipitator) are used as nano particle charger and collector, respectively. Pelletized MnO$_2$ catalyst or activated carbon is used fer ozone decomposition or adsorption material. AC voltage of 7～10 KV(rms) and 60 Hz is used as DBD plasma source. DC - 8 KV is applied to the ESP for particle collection. The overall particle collection efficiency for the hybrid system is over 85 % under 0.64 m/s face velocity. Ozone decomposition efficiency with pelletized MnO$_2$ catalyst or activated carbon packed bed is over 90 % when the face velocity is under 0.4 m/s in dry air.

• 공업화학
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• 제28권2호
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• pp.193-197
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• 2017

본 연구에서는 대형 직화구이 음식점으로부터 배출되는 유증기 및 미세먼지 제거를 위해 습식 플라즈마 전기집진 공정을 적용할 경우, 집진공정 후단에서 나오는 잔여 오존을 활용하여 제거되지 않은 아세트알데히드와 오존을 제거함으로써 복합악취를 저감할 수 있는 오존 산화 촉매 공정을 개발하였다. 망간산화물 기반 촉매는 분말 촉매 제조 후 압출하여 펠렛 형태로 성형하였으며, 성형촉매 상에서 아세트알데히드와 오존 모두 높은 제거율을 나타낼 수 있도록 최적 조건을 도출하고자 하였다. 제조한 $Mn_2O_3$와 $CuMnO_x$ 촉매는 각각의 성능을 평가하였으며, 이 두 가지 촉매를 2단으로 적용하였을 때 공간속도 $10,000h^{-1}$, 반응온도 $100^{\circ}C$인 조건에서 아세트알데히드는 85% 이상, 오존은 100% 저감시킬 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제31권10호
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• pp.2830-2834
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• 2010

The degradation efficiencies of phenol in aqueous solution were studied by semi-continuous experiments in the processes of ozone alone, ozone/bulky $Co_3O_4$ and ozone/$Co_3O_4$ nanoparticles. Catalyst samples (bulky $Co_3O_4$ and $Co_3O_4$ nanoparticles) were characterized by X-ray diffraction and transmission electron microscopy. The Brunauer-Emmett-Teller surface area, $pH_{pzc}$ and the density of surface hydroxyl groups of the two catalyst samples were also measured. The catalytic activity of $Co_3O_4$ nanoparticles was investigated for the removal of phenol in aqueous solutions under different reaction temperatures. Tert-butyl alcohol had little effect on the catalytic ozonation processes. Based on these results, the possible catalytic ozonation mechanism of phenol by $Co_3O_4$ nanoparticles was proposed as a reaction process between ozone molecules and pollutants.

• KIEE International Transactions on Electrophysics and Applications
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• 제3C권3호
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• pp.77-80
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• 2003

An innovative ozonizer has been developed using a high frequency, surface discharge and a high purity Ti-Si-AI ceramic catalyst as a dielectric component. Using a type of thin film, a thin cylindrical compound ceramic catalyst layer was adhered to the outside surface of its inner electrode. An alternating current (AC) exciting voltage with frequencies from 0.6 KHz to 1.0 KHz and peak-to-peak voltages of 4-6 ㎸ was applied between the electrodes to produce a stable high-frequency silent discharge. A substantial reduction of the exciting voltage was also enabled by means of a thin Ti-Si-Al ceramic catalyst tube. As a result, the ozonizer can effortlessly obtain the required ozone concentration (50-60 g/$m^2$ for oxygen) and high ozone efficiency consumption power (180 g/kWh for oxygen) with-out the assistance of any particular methods. For purposes of this experiment, oxygen gas temperature was set at 2$0^{\circ}C$, with an inner reactor pressure of 1.6 atm at 600 Hz and a flow rate of 2 l/min.