본 연구에서는 우리 나라의 대표적인 향신료 중의 하나인 건고추의 휘발성 유기성분을 n-pentane과 diethylether 혼합용매를 추출용매로 사용하여 연속증류추출장치로 휘발성 유기화합물을 추출하고 이를 GC/MS로 사용하여 분석확인하였다. 건고추와 조사된 건고추에서 확인된 성분은 각각 61종과 62종으로, 관능기별 상대 면적비는 대체적으로 terpene류, aldehyde류가 두드러지는 경향을 보여 건고추의 주요 휘발성 유기화합물에 크게 영

The feasibility and efficiency of the hydrogen peroxide produced by an electrolysis cell reactor was investigated. From regulating voltages for the given reaction time, the concentration of the hydrogen peroxide was gradually increased with increasing voltages. Optimal voltage range was found to be 10～15 V. The concentration of hydrogen peroxide was much higher with oxygen gas than without oxygen gas in the cathodic chamber. But there was a little difference in the generating rate of hydrogen peroxide regardless of the presence of nitrogen gas. Under given conditions, the maximum value of ICE(Instantaneous Current Efficiency) was about 38%, and then current density was 74 mA/cm2. The specific energy consumption was 0.694[㎾h/kg-H2O2]. Since Esp (Specific Energy Consumption)was very little value, It did not demand high energy in this system. Using the hydrogen peroxide gained in the experiment, Fenton's reaction was conducted and the removal of nitrobenzene, 3-chlorophenol and dye wastewater was studied. This results were very similar to the Fenton's reaction by using commercial hydrogen peroxide.

수리조선소에서 발생하는 TBT 함유 선박세척폐수의 용매추출 처리기술을 개발하기 위한 기초연구로서 인공 선박세척폐수를 이용하여 선박용 및 자동차용 디젤, 벙커 B유, 신너, 톨루엔, 에테르 등의 여러 가지 용매들의 TBT 추출효율을 비교하였으며, 추출효율에 대한 추출용매의 양 및 교반시간, 강도, pH 등의 추출조건의 영향을 평가하였다. 선박용 경유는 신나, 병커B 등에 비해 상대적으로 우수한 TBT 추출효율을 보였으며, 적정 추출용매 주입량은 폐수 IL 당 용매 10mL로 평가되었다 TBT 추출을 위한 교반강도가 50rpm에서 250rpm으로 증가함에 따라 잔류 TBT 농도는 약 120ppb에서 2.8ppb로 크게 감소하였다 잔류 TBT는 추출 1시간이후 크게 감소하였으며, 5시간 이후부터는 다시 증가하였다. 추출효율에 대한 Ph의 영향은 크지 않았으나, pH 6∼7의 약산성영역에서 양호한 추출효율을 보였다.

This study focuses on the measurement of airborne Volatile Organic Compounds (VOCs) in the Kumi electronic industrial complex during the time periods of August and September, 2002 and January and February, 2003. This study was based on the US-EPA method TO-14 while the VOCs were analyzed with GC/MSD. The toluene level revealed high concentration at all measurement sites. The areal rank of average concentrations of VOCs is as follows : industry1>industry2>urban>middle>residential. Concentrations of VOCs in Kumi electronic industrial ones were generally higher than at Yeochon and Ulsan industrial complexes. Dichloromethane and trichloroethylene, which are used as a cleaner in the process of electronic industries, were observed 4 to 8 times higher than those of other areas. Among the aromatic compounds, toluene showed the highest level, while the concentrations of dichloromethane and trichloroethylene were higher than those of other halogen compounds. In Kumi, toluene, trichloroethylene, and dichloromethane were confirmed as the major compounds of VOCs by this research.

Volatile organic compounds (VOCs) are present in essentially all natural and synthetic materials from petrol to flowers. In this study, indoor and outdoor VOCs concentrations of houses, offices and internet-cafes were measured and compared simultaneously with personal exposures of each 50 participants in Asan and Seoul, respectively. Also, factors that influence personal VOCs exposure were statistically analyzed using questionnaires in relation to house characteristics, time activities, and health effects. All VOCs concentrations were measured by OVM passive samplers (3M) and analyzed with GC/MS. Target pollutants among VOCs were Toluene, o-Xylene, m/p-Xylene, Ethylbenzene, MIBK, n-Octane, Styrene, Trichloroethylene, and 1,2-Dichlorobenzene. Indoor and outdoor VOCs concentrations measured in Seoul were significantly higher than those in Asan except Ethylbenzene. Residential indoor/outdoor (I/O) ratios for all target compounds ranged from 0.94 to 1.51 and I/O ratios of Asan were a little higher than those of Seoul. Relationship between personal VOCs exposure, and indoor and outdoor VOCs concentrations suggested that time-activity pattern could affect the high exposure to air pollutant. Factors that influence indoor VOCs level and personal exposure with regard to house characteristics in houses were building age, inside smoking and house type. In addition insecticide and cosmetics interestingly affected the VOCs personal exposure. Higher exposure to VOCs might be caused to be exciting increase and memory reduction, considering the relationship between measured VOCs concentrations and questionnaire (p<0.05).

The emission of volatile organic compounds (VOCs) generated from painting and coating processes is a worldwide problem as contributing factors to the development of photochemical smog and other environmental problems. Common methods of reducing VOC emissions are adsorption on activated carbon, membrane separation, absorption, incineration, or catalytic oxidation. In this article, the environmental issues caused by VOC emissions and the trend of legislation against such emissions will be surveyed first. Several conventional control technologies will then be summarized and the characteristics of each process will be introduced. Lastly, some examples will be described to show the hybrid processes which have been industrially applied for the recovery of VOC.

This work aims the search of environmentally friendly pre-treatment technologies to develop chromate replacements for metal finishing industries due to its toxicological properties. Since the corrosion resistance of steel was strongly related to water permeation, galvanized steel sheets were treated with various hydrophobic silane compounds and water-suspended polymer solution. Also, plasma gas discharge was applied to modify the surface of a polymer coated-steel sheet to be hydrophobic. The surface hydrophobicity of materials was introduced by CF3H plasma exposure. The corrosion property before and after the plasma treatment was investigated in a slat spray tester with 3.5 wt.% NaCl at 35 ℃. The results showed that both silane/polymer double coatings and plasma treatment of the galvanized steel exhibited significant retardation of corrosion.

The purpose of this study was to develop the preliminary source fingerprints of volatile organic compounds (VOC). The source categories studied were vehicles, gasoline vapor, gasoline storage tank, coating, dry cleaning and road covering. The source samples were collected using 6L electro-polished stainless steel canisters for about 20 seconds. From this study, the main component emitted from VOC sources in Korea was toluene. The toluene proportion for road covering, vehicles, coating and gasoline vapor were 35, 18, 16 and 5%, respectively. The C2-C5 alkane and alkene compounds were mainly emitted from vehicles, gasoline vapor and gasoline storage tank. The main compounds of coating were m/p-xylene(34%), toluene(16%), 1,2,4-TMB(10%) and o-xylene(9%), which are aromatic hydrocarbons. In the case of dry cleaning, nonane(41%), 1,2,4-TMB (22%) and 1,3,5-TMB(13%) were mainly emitted.

The cork have been preferred over the conventional materials, zeolite, ceramics, and lignite as a biofilter medium. During the 6 months of operation, the performance of the cork biofilter was considered good with 150ppm of mixture BTX vapor efficiencies greater than 90% at 60 second of EBCT. It was observed 56 % of removal efficiency under tranisition conditions at first stage, and then the removal efficiency was increased to above 90 %, and the sustainability of removal efficiency was maintained. At second stage, the performance of cork biofilter was not decreased 90 % efficiency with 150 ppm BTX at 30 sec. EBCT. The production of CO2 due to microbial respiration was increased to the 40 % on the operation of cork biofilter

A numerical model is investigated to predict a behavior of the gaseous volatile organic compounds and a subsurface contamination caused by them in the unsaturated zone. Two dimensional advective-dispersion equation caused by a density difference and two dimensional diffusion equation are computed by a finite difference method in the numerical model. A laboratory experiment is also carried out to compare the results of the numerical model. The dimensions of the experimental plume are 1.2m in length, 0.5m in height, and 0.05m in thickness. In comparing the result of 2 methods used in the numerical model with the one of the experiment respectively, the one of the advective-dispersion equation shows better than the one the diffusion equation.

This study was carried out to evaluate the pollutant removal efficiencies of the advanced drinking water treatment using ozonation process. For raw water, Nakdong River was used. By conducting batch test of ozonation, the following results were obtained. When ozone dosage of 5 mg/ℓ was used, ozone transfer and utilization efficiencies of the ozonation were 94 to 92%, respectively. Removal efficiencies of single VOC compound or mixed VOC compounds in the raw water were 80% to 90% by the ozonation with 2 mg/ℓ dosage and 10 minutes contact time. Removal efficiencies of ABS by the ozonation with 1 mg/ℓ, 3 mg/ℓ dosage and 20 minutes contact time were 83% to 96% , respectively. Almost 67% of chlorophyll-a at the concentration of 38.4㎍/ℓ was removed by ozonation at ozone dosage of 1 ㎎/ℓ for 20 min. Considering the efficiency of ozone utilization and water treatment, the most effective ozonation could be obtained with high ozone dosage and short contact time.

This study analyzed concentrations of volatile organic compounds (VOCs) produced from incineration of papers at 600 ℃. The papers used in this study included A4 papers (new, printed with ink-jet, printed with carbon), newspapers (printed with bean oil, printed with a general newspaper ink), packaging box, document envelope, single-use paper cup, and cosmetic tissue. Papers were heated from room temperature upto 600℃ providing air inside of the electric furnace and then they were oxidized for 80 minutes at 600℃ maintaining the same air supply. VOCs emitted from the incineration process were sampled using an air sampling pump and bags for 160 minutes and then the components and concentrations of the VOCs were analyzed by a GC-MS. The most prominent chemical structure of the Vous identified from incineration of the papers was furans and then furans were followed by aromatics and aliphatic alkenes. About 40 % of the identified VOCs contained double bonds, which have relatively a high ozone (ground level) formation potential, within their molecular structure. Also, some cancer suspecting compounds like benzene, dichloromethane and chloroform were identified.

UV photolysis process is little known in parts of air pollution treatment, so there are not many applications in field. Therefore we have to do more experiment and study application possibility for treatment of VOCs(Volatile organic compounds). To solve these problems, we have been studying for simultaneous application of this technology. It has shown that concentration of TCE and B.T.X., diameter of reactor and wavelength of lamp have effected on decomposition efficiency. Analysis of TCE and B.T.X. concentration was carried out by GC-FID. A cylinderical reactor consisting of a quartz tube and a centrally located lamp(ψ25mm) was used. The length and diameter of reactor were 1800mm, 75mm. It has shown that the generated ozone concentration goes up 250ppm when using 64watt ozone lamp. When using Photolysis process only, the rates of fractional conversion of each material are TCE 79%, Benzene 65%, Toluene 68%, Xylene 76%. This phenomenon can be rationalized in terms of the different bond energy that indicates how easily VOCs species can be decomposed.

In this study, the distribution characteristics of volatile organic compounds (VOCs) were investigated on the seasonal basis across spring, summer, and fall during the year of 1998. According to this analysis, most VOC species investigated exhibited strong temporal trends. Over diurnal scale, there distribution characteristics were affected by seasonal factors strongly. While they showed high day/night ratio pattern during spring, the pattern was reversed during fall. When the seasonal mean values were compared between the two seasons, the spring values were systematically higher than their counterparts in most cases. In addition when our VOC measurement data were compared with those reported from elsewhere, we were able to conclude that the VOC levels in the study area are comparable to the level weakly impacted by the regional emissions of VOCs. Although our data are not sufficient enough to systematically explain the atmospheric distribution and behavior of VOCs, the findings of strong correlations among some of VOC species suggests strong need for investigating their interactions in the earth's atmosphere.