• 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%).

• 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.

• 산업기술연구
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• 제27권A호
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• pp.25-29
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• 2007

Ozone alone, Ozone/GAC, Ozone/$H_2O_2$ and Ozone/GAC/$H_2O_2$ processes were introduced for treatment of humic acid, which is a representative refractory organic compound. $H_2O_2$ and GAC used as catalysts for experiment. The treatment efficiencies of humic acid in each process were analyzed for pH variation, DOC removal, and $UV_{254}$ decrease. $UV_{254}$ decrease in Ozone/GAC and Ozone/GAC/$H_2O_2$ processes were the highest with about 93%, and Ozone alone and Ozone/$H_2O_2$ processes were 88%. DOC removal in Ozone/GAC/$H_2O_2$ process was the highest with 71%. Removal by Ozone/GAC, Ozone alone, and Ozone/$H_2O_2$ processes were 66%, 39%, and 47%, respectively.

• 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.

• 한국환경과학회지
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• 제15권3호
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• pp.193-201
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• 2006

Advanced oxidation processes involving $O_3/H_2O_2$ and $O_3/catalyst$ were used to compare the degradability and the effect of pH on the oxidation of 1,4-dioxane, Oxidation processes were carried out in a bubble column reactor under different pH. Initial hydrogen peroxide concentration was 3.52 mM in $O_3/H_2O_2$ process and 115 g/L (0.65 wt.%) of activated carbon impregnated with palladium was packed in $O_3/catalyst$ column. 1,4-dioxane concentration was reduced steadily with reaction time in $O_3/H_2O_2$ oxidation process, however, in case of $O_3/catalyst$ process, about $50{\sim}75%$ of 1,4-dioxane was degraded only in 5 minutes after reaction. Overall reaction efficiency of $O_3/catalyst$ was also higher than that of $O_3/H_2O_2$ process. TOC and $COD_{cr}$ were analyzed in order to examine the oxidation characteristics with $O_3/H_2O_2\;and\;O_3/catalyst$ process. The results of $COD_{cr}$ removal efficiency and ${\Delta}TOC/{\Delta}ThOC$ ratio in $O_3/catalyst$ process gave that this process could more proceed the oxidation reaction than $O_3/H_2O_2$ oxidation process. Therefore, it was considered that $O_3/catalyst$ advanced oxidation process could be used as a effective oxidation process for removing non-degradable toxic organic materials.

• 산업기술연구
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• 제28권A호
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• pp.23-26
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• 2008

Ozone/GAC and ozone-GAC 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. $UV_{254}$ decrease in all processes was comparatively high with efficiency over 92%. $UV_{254}$ decrease in ozone alone process was 85%. DOC removal in Ozone-GAC process was the highest with 75%. Removal by Ozone/GAC, Ozone alone processes were 71% and 33% respectively.

• 조명전기설비학회논문지
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• 제25권10호
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• pp.116-124
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• 2011

In this work, the effect of the initial concentration of methanol and ethanol, and the addition of oxygen molecules were discussed to improve the hydrogen generation using non-thermal plasma reactor effectively. In addition, the effect of ozone decomposition catalyst of manganese dioxide and its quantity was investigated. First, hydrogen concentration increased until an initial concentration of about 40,000[ppm] of methanol and thereafter it was saturated. Henceforth, hydrogen concentration decreased with increasing the oxygen percent on the carrier gas of nitrogen about both substances. Related with the effect of catalyst, it increased upto 60[g], but it was not changed largely after that. Consequently, it is confirmed that the hybrid process using plasma process and catalytic surface chemical reaction is a very promising way to increase the efficiency of hydrogen generation as investigated in this work.

• 공업화학
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• 제20권1호
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• pp.87-93
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• 2009

팔라듐 금속을 활성탄과 알루미나에 담지시켜 Pd/AC (Pd/활성탄), Pd/AO (Pd/알루미나) 촉매를 제조하고, 오존/촉매공정에 적용하여 담지체의 종류에 따른 촉매 특성을 비교하였다. 담지체를 달리한 촉매 일정량을 오존포화수에 투입하고 오존분해능을 비교해 본 결과, 담지체의 종류에 따른 효율의 변화는 없었다. 오존단독공정과 Pd/AC, Pd/AO 촉매를 이용한 오존/촉매공정에서 dichloroacetic acid (DCAA)의 분해율 및 산화특성(TOC, $COD_{Cr}$)을 비교해 본 결과, 오존/촉매공정의 제거효율이 높았으며, 담지체에 따른 특성변화는 거의 없었다. DCAA 농도를 일정하게 하고 오존공급량을 변화시켜 제거율을 확인한 결과, 어느 수준까지는 오존공급량 증가에 따라 제거율이 상승하였지만, 1.0 L/min 이상의 오존공급량에서는 공급량에 비례하여 제거율이 상승하지 않았다. 이러한 원인은 DCAA의 완전산화에 의해 생성된 중탄산염과 분해과정에서 발생된 염소이온이 하이드록실 라디칼(${\cdot}OH$)의 스케빈저(scavenger)로 작용한 것 같았다.

• 한국환경과학회지
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• 제18권4호
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• pp.445-450
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• 2009

In this study, the fundamental experiments were performed for catalytic oxidation of NO (50 ppm) on $MnO_2$ in the presence of ozone. The experiments were carried out at various catalytic temperatures ($30-120^{\circ}C$) and ozone concentrations (50-150 ppm) to investigate the behavior of NO oxidation. The honeycomb type $MnO_2$ catalyst was rectangular with a cell density of 300 cells per square inch. Due to $O_3$ injection, NO reacted with $O_3$ to form $NO_2$, which was adsorbed at the $MnO_2$ surface. The excessive ozone was decomposed to $O^*$ onto the $MnO_2$ catalyst bed, and then that $O^*$ was reacted with $NO_2$ to form $NO_3^-$. It was found that the optimal $O_3$/NO ratio for catalytic oxidation of NO on $MnO_2$ was 2.0, and the NO removal efficiency on $MnO_2$ was 83% at $30^{\circ}C$. As a result, NO was converted mainly to $NO_3^-$.

• 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.