• 분석과학
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• 제18권2호
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• pp.130-138
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• 2005

VOCs (Volatile Organic Compounds)는 대기오염의 주원인으로서 인식되어왔다. 촉매산화는 저온에서 높은 효율을 나타내기 때문에 VOCs 제거를 위한 가장 중요한 처리기술중 하나이다. 이 연구에서는 $TiO_2$ 담체에 Pt, Ir 그리고 Pt-Ir을 담시지켜 촉매를 제조하였다. 반응물로서 Xylene을 사용하였다. 단일 또는 두 가지 이상의 촉매들은 함침법에 의해 준비하였고, X-ray diffraction (XRD), X-ray photo electron spectroscopy (XPS), transmittence electron microscophy (TEM) 분석을 통하여 특성화하였다. 그 결과 Pt 촉매는 Ir 촉매에 비해 더 높은 전환율을 나타내었고, Pt-Ir 촉매는 가장 높은 전환율을 나타내었다. VOCs 산화에서, Pt-Ir 촉매는 다양한 활성점을 나타내었고 그것은 Pt의 metal 영역을 강화시켰다. 따라서 두 가지 금속으로 이루어진 촉매가 단일 금속으로 이루어진 촉매에 비해 VOCs 전환율이 더 높았다. 동역학적으로 VOCs 산화는 1차 반응이다. 이 연구에서 Pt에 Ir을 소량 첨가함으로써 VOCs 산화반응에 효과적이었다.

• 보존과학연구
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• 통권35호
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• pp.25-44
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• 2014

이 연구에서는 유물 전시관을 대상으로 Active type과 Passive type에 의한 VOCs의 측정 분석법을 사용하여 전시실 내 외의 연중, 계절별 농도를 조사하고 측정방법에 따른 농도 비교를 통해 측정방법 간의 상관성을 비교하였다. 그 결과, Active type에 의한 전시실 TVOC의 연중 평균 농도는 $906.5{\mu}g/m^3$으로 대부분 조사 기간 동안 환경부 기준을 1.8배 이상 초과하였다. Active type에 의한 전시실의 ${\Sigma}VOCs$ 농도는 Passive type 보다 높았다. 일부 VOCs는 시간의 경과에 따라 감소하나 일시적인 상승 경향을 나타내기도 했다. Active type에 의한 전시관의 연평균 I/O비는 TVOC 9.0, ${\Sigma}VOCs$는 34.0으로 조사되어 ${\Sigma}VOCs$가 전시실 내부에서 다량 발생하는 것을 확인하였다. 두 방법 간의 상관성 분석 결과, ${\Sigma}VOCs$의 상관계수는 0.367이었으며 톨루엔은 0.567로 두 분석 방법 간의 연관성이 가장 큰 것으로 조사되었다.

• 한국환경보건학회지
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• 제46권3호
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• pp.256-266
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• 2020

Objectives: The concentrations and distribution characteristics of volatile organic compounds (VOCs) in an industrial complex and surrouding affected residential areas were investigated in an effort to support the efficient management of VOCs. Methods: The atmospheric concentrations of VOCs were analyzed at sites around the Sihwa-Banwol complex located in the cities of Siheung and Ansan and in the surrounding affected residential areas. The appearance of VOCs and the characteristics of their temporal and spatial distribution were evaluated. Results: The total VOC concentrations in the industrial complex were detected at 1.9-2.3 times higher than in the affected areas, but the daily VOCs distributions showed similar patterns in both sites. In particular, it was confirmed that the composition ratio of the VOCs and concentration fluctuations over time in the affected areas are similar to those in the adjacent industrial complex. VOC levels in the affected areas were higher than in residential areas in cities without an industrial complex. Conclusions: VOCs in residential areas near an industrial complex were highly distributed due to the influence of continuous pollutant emissions from the industrial complex. Therefore, the management of VOCs in the atmosphere of the affected area is important for identifying and managing the sources of VOCs detected in high concentrations in the industrial complex.

• 한국대기환경학회지
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• 제24권3호
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• pp.275-283
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• 2008

Since mobile source is a major source of VOCs, quantifying emissions from motor vehicles is an important factor to control VOCs in atmosphere. In this study, in order to evaluate tailpipe VOCs emissions from motor vehicles, mass emissions of non-methane volatile organic compounds from 45 vehicles were determined. Measurements were made on a chassis dynamometer using CVS-75 mode and speed specific drive modes. Target VOCs are 53 compounds determined as the volatile ozone precursors. The individual VOCs composition of vehicle emission and emission rates were also determined. In case of gasoline vehicles, VOCs emission from over 80,000 km vehicles were about 46% larger than less 80,000 km vehicles. The difference in benzene and toluene according to driving mileage was 44% and 26% respectively. The composition of VOCs were different by fuel type. The order of VOCs composition was paraffins>aromatics>olefins in gasoline vehicle emissions, paraffins>olefins>aromatics in light duty diesel vehicle emissions. The VOCs emissions were decreased as vehicle speed increasing. These results will be used to calculate total VOCs emissions from automobiles in the future.

• 한국대기환경학회지
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• 제21권1호
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• pp.83-96
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• 2005

The purposes of this study were to characterize the local levels of VOCs (volatile organic compounds), to develop source profiles of VOCs, and to quantify the source contribution of VOCs using the CMB (chemical mass balance) model. The concentration of VOCs had been measured every 6-day duration in the SRO monitoring site in the Yeosu Petrochemical Industrial Complex from September 2000 to August 2002. The total of 35 target VOCs, which were included in the TO-14 designated from the U.S. EPA, was selected to be monitored in the study area. During a 24-h period, the ambient VOCs were sampled by using canisters placing about 10 ～ 15 m above the ground level. The collected canisters were then analyzed by a GC-MS in the laboratory. Aside from ambient sampling at the SRO site, the VOCs had been intensively and massively measured from 8 direct sources and 4 general sources in the study area. The results obtained in the study were as follows; first, the annual mean concentrations of the target VOCs were widely distributed regardless of monitoring sites in the Yeosu Petrochemical Industrial Complex. In particular, the concentrations of BTX (Benzene, Toluene, Xylene), vinyl chloride were higher than other target compounds. Second, based on these source sample data, source profiles for VOCs were developed to apply a receptor model, the CMB model. Third, the results of source apportionment study for the VOCs in the SRO Site were as follows; The source of petrochemical plant was apportioned by 31.3% in terms of VOCs mass. The site was also affected by 16.7% from wastewater treatment plant, 14.0% from iron mills, 8.4% from refineries, 4.4% from oil storage, 3.8% from automobiles, 2.3% from fertilizer, 2.3% from painting, 2.2% from waste incinerator, 0.6% from graphic art, and 0.4% from gasoline vapor sources.

• 한국도시환경학회지
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• 제18권4호
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• pp.503-509
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• 2018

본 연구에서는 양자전이 비행시간질량분석기(PTR-ToF-MS)를 이용하여 반도체 공정의 작업환경(PHOTO, FPD, OLED, WET 공정)에서 VOCs를 실시간으로 모니터링하였다. 작업환경에서 평균 VOCs 농도는 PHOTO 6.5 ppm, FPH 6.4 ppm, WET 2.0 ppm, OLED 1.3 ppm이었다. VOCs 중 methyl ethyl ketone이 2.8 ppm (69%), acetaldehyde가 0.5 ppm (13.2%)로 나타났다. 반도체 공정 특성에 따라 다양한 VOCs 가 작업환경에서 관측되었다. 관측된 VOCs 농도는 작업환경기준보다 낮지만, 이러한 VOCs를 지속적으로 모니터링하여 효과적으로 관리해 나갈 필요가 있다.

• 한국환경보건학회:학술대회논문집
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• 한국환경보건학회 2004년도 International Conference Global Environmental Problems and their Health Consequences
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• pp.139-141
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• 2004

Emission of volatile organic compounds (VOCs) are one of the popular issues of air pollution in Korea, especially in Ulsan city, where much chemical plants are located. It is necessary to detect the VOCs precisely in order to control the air pollution during the plant operation. In general, to examine the concentration of VOCs, gas chromatography (GC) is used. However, most plant operators are using the easy operating handy VOCs detector, which is imported, because GC is difficult to treat and the installation price is high although it is very useful equipment. Therefore, the development of the VOCs detector becomes one of the urgent issues. In this study, sensing characteristics of selected VOCs for the development of VOCs detector was investigated. Semiconductor sensor and several VOCs such as aliphatic, aromatic, and non-homogeneous hydrocarbons were used for the experiment. Through the various experiments, sensor used in the experiment has shown high linearity and sensitivity for most VOCs in the range of 1 -500 ppm concentration.

• 한국환경과학회지
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• 제18권3호
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• pp.283-288
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• 2009

This is a study on the volatile organic compounds(VOCs) concentrator with zeolite adsorptive honey rotor and catalytic combustion system for abating VOCs emitted from printing industry. VOCs emitted from the printing industry is mainly caused by organic solvent of printing ink. The content of organic solvents in printing ink varies from 40% to 75% and its content in the gravure ink is higher than that in any other ink. The average concentrations of each VOCs are 139 ppm for toluene, 152.1 ppm for MEK, 256.9 ppm for methanol and 42.9 ppm for isopropyl alcohol. We used zeolite honeycomb for absorbent of VOCs concentrator and palladium for catalyst combustion system. This system abated over 96% of emitted total VOCs, 98% of toluene, 100% of MEK, 92% of methanol and, 100% of isopropyl alcohol. It is concluded that the low-leveled high-volume VOCs emitted from printing process were removed almost by concentrator with zeolite adsorptive honey rotor and catalytic combustion system.

• 대한환경공학회지
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• 제32권4호
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• pp.393-398
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• 2010

본 연구에서는 2007년 12월 태안반도의 원유유출 사고 당시 대기중 방출된 휘발성유기화합물의 농도를 추정하고자 원유유출 모의시험 챔버를 제작하였다. 이 챔버를 이용하여 온도와 기류를 변수로 두고, 시간에 따른 총 VOCs 농도와 개별 VOCs 농도의 변화를 측정 분석 하였다. 기류가 강할수록 VOCs의 농도가 낮고 온도가 높을수록 VOCs의 농도가 높다는 것을 알 수 있었다. 또한, 총 휘발성유기화합물(TVOCs)은 원유가 유출된 직후 6일이 지나면서 초기농도 대비 90% 이상이 감소하는 것으로 나타났다.

• 환경위생공학
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• 제17권1호
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• pp.52-56
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• 2002

The study was carried out to evaluate the characteristics of biodegradation by Pseudomonas putida G7 in soil column. The reactor system was used to investigate mass transfer of VOCs as Toluene in a column of unsaturated soil. Determination of the fate of VOCs in unsaturated soil is necessary to evaluate the feasibility of natural attenuation as a VOCs remediation strategy. The objective of this study was to develop a mechanistically based mathematical model that would consider the interdependence of VOC transport, microbial activity, and sorptive interactions in a moist, unsaturated soil. Because the focus of the model was on description of natural attenuation, the advective VOCs transport that is induced in engineered remediation processes such as vapor extraction was not considered. It can be concluded that the coefficient for gas liquid mass-transfer was found to be a key parameter controlling the ability of bacteria to VOCs. Finally, it appeared that bioremediation technology of VOCs which are difficult to be decomposed by chemical methods.