• Proceedings of the Korea Air Pollution Research Association Conference
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• 2001.11a
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• pp.225-226
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• 2001

휘발성 유기화합물(VOCs)은 광화학적 오존 형성으로 인한 간접 오염뿐만 아니라 그 자체가 독성을 지니고 있어 직접적으로도 인체에 유해한 영향을 줄 수 있으며, 유류 및 유기 용제를 사용하는 작업장에서뿐만 아니라 연소 관련 오염원이 없는 실내 환경에서도 일부 VOCs는 높은 농도를 나타낼 수 있으므로 작업장 및 실내 환경에서의 VOCs 처리에 대한 중요성이 증대되고 있다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.04a
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• pp.181-182
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• 2002

휘발성유기화합물(Volatile Organic Compounds: VOCs)은 석유화차광장, 정유공장, 도료공장, 도장공장 등의 제조공정 및 저장시설로부터 주로 발생되며, 증기압이 높아 대기 중으로 쉽게 증발되고 대기 중에서 질소산화물들과 광화학반응을 일으켜 광화학스모그를 유발시키는 물질로 대기 중의 오존층을 파괴하고 인체에 매우 유해한 물질로 알려져 있다. (중략)

• Economic and Environmental Geology
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• v.43 no.6
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• pp.565-571
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• 2010

An innovative application of surfactant-enhanced air sparging(SEAS) technique was developed in this study. Using a laboratory-scale physical model packed with water-saturated sand, air sparging was implemented to remove water-dissolved toluene that was introduced into a specific depth of the system with finite vertical width prior to sparging. An anionic surfactant(Sodium dodecylbenzene sulfonate) was introduced into the contaminated layer as in dissolved form in the toluene-contaminated solution for SEAS, whereas no surfactant was applied in the control experiment. Due to the suppressed surface tension of water in the surfactant(and toluene)-containing region, the toluene removal rate increased significantly compared to those without surfactant. More than 70% of the dissolved toluene was removed from the contaminated layer for SEAS application while less than 20% of toluene was removed for the experiment without surfactant. Air intrusion into the contaminated layer during sparging was found to be more effective than that without surfactant, enhancing air contact with toluene-contaminated water, which resulted in improved volatilization of contaminant. This new method is expected to open a new option for remediation of VOC(volatile organic compound)-contaminated aquifer.

• Journal of Korean Society for Atmospheric Environment
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• v.18 no.1
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• pp.51-58
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• 2002

Destruction process of toluene using a wire-cylindrical BBD (Dielectric Barrier Discharge) reactor packed with catalysts was investigated to characterize the synergetic effects of non-thermal plasma and catalyst process. The catalysts used in the present study were ${\gamma}$-Al$_2$BO$_3$ and Pt/${\gamma}$-Al$_2$O$_3$. Under the numerous test conditions, specific energy density (SED (J/L)) and the conversion of toluene, defined as (1 -[C$_{f}$]/[C$_{i}$]), were measured. The test results showed that toluene decomposition efficiency followed the pseudo-first order in the case of plasma only process. The pseudo-first order process, however, was modified to pseudo-zeroth order reaction in the case of catalyst-assisted plasma process. This modification of the reaction order was verified based on a simple kinetic model proposed in the present study. Owing to the modification of reaction order, which resulted from the catalytic process, the specific energy to achieve the high removal efficiencies, i.e. 80~90%, was reduced significantly.y.y.

• Journal of Microbiology and Biotechnology
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• v.19 no.9
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• pp.1028-1033
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• 2009

In this study, the dynamics of living cells (LC) and dead cells (DC) in a laboratory-scale biofilm membrane bioreactor for waste gas treatment was examined. Toluene was used as a model pollutant. The bacterial cells were enumerated as fluoromicroscopic counts during a 140 operating day period using BacLight nucleic acid staining in combination with epifluorescence and confocal laser scanning microscopy (CSLM). Overall, five different phases could be distinguished during the biofilm development: (A) cell attachment, (B) pollutant limitation, (C) biofilm establishment and colonization, (D) colonized biofilm, and (E) biofilm erosion. The bioreactor was operated under different conditions by applying different pollutant concentrations. An optimum toluene removal of 89% was observed at a loading rate of 14.4 kg $m^{-3}d^{-1}$. A direct correlation between the biodegradation rate of the reactor and the dynamics of biofilm development could be demonstrated. This study shows the first description of biofilm development during gaseous toluene degradation in MBR.

• Microbiology and Biotechnology Letters
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• v.22 no.6
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• pp.685-691
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• 1994

The biodegradation of aromatic compounds by mixed and monoculture was investigated in an artificial wastewater containing 500 mg/l of benzene(B), phenol(P), and toluene(T) in various combinations. None of three strains utilized P-xylene(X) as a carbon source, but they grew well on p-xylene in mixtures with benzene and toluene. In the mixed culture on mixed substrate, the length of lag phase was different depending on the nature of mixture. Cell growths of Flavobac- terium sp. BEN2 and Acinetobacter sp. GEM63 were inhibited in the presence of a 500 mg/l of phenol. When the mixed culture of three strains was cultured in a bench-scale reactor containing artificial wastewater, each of benzene, phenol, and toluene was not detected at 30 hrs, 50 hrs, and 12 hrs after incubation in the treatment. The removal rates of COD$_{t}$(total COD) and COD$_{s}$,(soluble COD) of upper phase after centrifugation during early 50 hrs were ca. 80% and ca. 93.8%, respectively.

• Journal of odor and indoor environment
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• v.17 no.4
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• pp.396-403
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• 2018

In this study, volatile organic compounds (VOCs) emitted from printing industries were analyzed, and an inorganic adsorbent, ${\gamma}-alumina$, was selected for the effective control of the VOC emissions. Printing processes commonly require inks, thinners, and cleaners, and they were mixed organic solvents containing aromatic compounds, ketones, and alcohols. Therefore, toluene, methyl ethyl ketone (MEK), and isopropyl alcohol (IPA) were selected as model compounds for this study. The adsorptive properties using ${\gamma}-alumina$ were determined for the model compounds. Both batch isotherm and continuous flow column tests demonstrated that the adsorption capacity of MEK and IPA was 3~4 times higher than that of toluene. The column test performed at an inlet toluene concentration of 100 ppm showed that an 80% breakthrough for toluene was observed after 3 hours, but both MEK and IPA were continuously adsorbed during the same time period. A numerical model simulated that the ${\gamma}-alumina$ could remove toluene at a loading rate of 0.4 mg/min only for a 4-hour period, which might be too short of a duration for real applications. Consequently, lifetime enhancement for ${\gamma}-alumina$ must be implemented, and ozone oxidation and regeneration would be feasible options.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2005.11a
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• pp.501-503
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• 2005

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2008.04a
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• pp.124-125
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• 2008

• Proceedings of the Microbiological Society of Korea Conference
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• 1999.04a
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• pp.52.2-52.2
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• 1999