• 한국환경과학회지
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• 제5권6호
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• pp.749-755
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• 1996

In order to grasp a characterization of low boiling point chlorinated organic compounds, this study which were carried out at the 8 stations for precipitation samples in the Pusan area during the period from February to September 1995. As a result, low boiling chlorinated organic compounds were estimated that it was dissolved by a portion of precipitation, and it be able to shift at the surface of the each. Concentration of low boiling point chlorinated organic compounds in precipitation are increased with increase of temperature, and estimated that air pollution compounds of as a rule in atmosphere.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 총회 및 춘계학술발표회
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• pp.58-61
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• 2002

An alternative to pump and treat groundwater remediation is the use of reactive barriers. Zero valent iron (ZVI) is particularly useful as a reductant of chlorinated hydrocarbons because of its low cost and lack of toxicity ZVI can drive the dechlorination of chlorinated organic compounds and the reduction of chromium from the Cr(Ⅵ) to the Cr(III) state. The contaminants in subsurface environment usually exist as the mixed compounds. Therefore, the objective of this research is to study the effect of the other compounds on TCE removal by ZVI. The removal mechanism of TCE by ZVI is separated the dechlorination and sorption. TCE removal by ZVI slightly increased in presence of naphthalene as the non-reduced compound. TCE removal by ZVI remarkable decreased in presence of carbon tetrachloride, nitrate, and chromate as the reduced compounds. This research suggests that the effect of the coexisted compounds on the removal chlorinated compounds by reactive barrier technology should be considered for practical application.

• 생명과학회지
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• 제24권8호
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• pp.887-894
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• 2014

유기염소계 난분해성 산업폐수처리에 효과적인 미생물제제 개발을 위하여 PCP (pentachlorophenol)와 TCE (trichloroethylene) 등과 같은 유기계 염소화합물이 오염되어있는 토양 및 산업폐수로부터 PCP 분해활성이 높은 GP5, GP19와 TCE 분해활성이 높은 GA6, GA15를 분리하였다. 이들 분리균주 GP5, GP19, GA6, GA15등은 Acetobactor sp., Pseudomonas sp., Arthrobacer sp., Xanthomonas sp.과 유사한 것으로 나타나 최종적으로 Acetobacter sp. GP5, Pseudomonas sp. GP19, Arthrobacer sp. GA6, Xanthomoas sp. GA15로 명명하였다. 유기염소계 산업폐수의 처리를 위한 복합미생물제제 OC17은 PCP와 TCE를 분해하는 4개의 분리 분리균주와 방향족화합물 분해균주인 Acinetobacter sp. KN11, Neisseria sp. GN13의 배양액을 혼합하여 제조하였다. 복합미생물제제 OC17은 $2.8{\times}10^9CFU/g$의 균체수를 갖고 있으며, 밀도는 $0.299g/cm^3$, 수분함량은 26.8%를 나타내었다. 복합미생물 제제 OC17은 PCP 500 mg/l가 포함되어있는 인공폐수를 이용한 실험에서 배양 65시간에 87%의 분해효율을 나타내었고, TCE (300 uM)의 분해효율은 배양 50시간에 90%의 분해효율을 나타내었다. 복합미생물제제 OC17을 이용한 유기 염소계 산업폐수의 처리효율 시험을 위한 연속배양 실험 에서 10일간 처리 하였을 때 91%의 COD 제거효율을 나타내었다.

• Journal of the Korean Wood Science and Technology
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• 제12권2호
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• pp.27-34
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• 1984

In order to investigate the acidic chlorinated compounds in pulp bleaching spent liquor, the lignin model compounds, coniferyl alcohol(mp $74^{\circ}C$), ${\omega}$-(2-methoxyphenoxy)-acetoguaiacone(mp $93^{\circ}C$) and dehydrodiisoeugenol(mp $133^{\circ}C$), were synthesized and chlorinated by chlorine in glacial acetic acid. From the chlorinated products, the following chlorine-containing aromatic compounds were identified by TLC. In coniferyl alcohol the chlorine-substituted compounds at 4-, 5-and 4,5-position of aromatic nucleus were identified and in ${\beta}$-0-4 type the compounds substituted chlorine for alkyl group and/or hydrogen at land 1,4-position of aromatic nucleus expected to be formed by electrophilic displacement from ${\omega}$-(2-methoxyphenoxy)-acetoguaiacone were not identified but the chlorine-substituted compounds at 4-, 5-, 6- and 5,6-position of aromatic nucleus were identified.

• 한국토양환경학회지
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• 제4권3호
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• pp.85-93
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• 1999

유기 염소계 화합물과 니트로기 방향족 화합물 같은 난분해성 유해물질을 처리함에 있어, 0가 철 분말의 사용은 최근에 가장 활발히 논의되고 있는 기술 가운데 하나이다. 본 연구에서는 나노크기의 0가 철 분말을 실험실에서 만들어 유기 염소계 화합물의 탈염소화 반응과 니트로기 방향족 화합물의 니트로기 변환실험을 혐기성 회분식 반응조에서 실시하였다. 매우 큰 비표면적과 높은 반응성을 가지고 있는 나노크기 0가 철 입자는 10mg/$\ell$로 농도수용액상에 존재하는 TCE, 클로로포름, 니트로 벤젠, 니트로 톨루엔, 디니트로 밴젠, 디니트로 톨루엔등의 물질을 상온.상압의 조건에서 빨리 제거할 수 있었다. 본 연구에서는 반응 시간 30분 안에 TCE는 에탄으로, 클로로포름은 메탄으로 탈염소화 되었고, 니트로기 방향족 화합물의 니트로기는 모두 아민기로 변환되었다. 이러한 결과들은 유기 염소계 화합물과 니트로기 방향족 화합물 같은 난분해성 유해물질로 오염된 지하수나토양을 복원함에 있어, 나노크기의 0가 철 분말을 이용한 화학적 처리기술의 잠재성을 나타내주는 것이다.

• 한국환경성돌연변이발암원학회지
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• 제21권2호
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• pp.118-121
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• 2001

The predictive screening of various molecular descriptors for predicting carcinogenic, mutagenic, teratogenic and alkylation activity of chlorinated disinfection byproducts (DBPs) has been investigated for the application of quantitative structure-activity relationships (QSAR). The toxicity index for 29 compounds were computed by the PASS program and active values were employed in this study. Studies show that different descriptors account for the model equation of each genotoxic endpoint and that thermodynamic descriptors significantly played a major role on prediction of endpoints of chlorinated aliphatic compounds.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 1995년도 춘계학술발표회 초록집
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• pp.31-40
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• 1995

The degradation of aqueous chlorinated compounds such as trichloroethylene (TCE), tetrachloroethylene (PCE) and dichloroacetic acid (DCA) to $CO_2$ and HCl was accomplished in the presence of UV light and suspended TiO$_2$ slurries. The decomposition of chlorinated hydrocarbons at 253.7 m irradiation was more effective than that at 360 nm irradiation. Our results show that 253.7 nm irradiation alone can be used for decomposing some chlorinated hydrocarbons such as PCE and TCE.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권1호
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• pp.78-84
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• 2013

This study was conducted in order to evaluate the removal process for long-term contamination sources including chlorinated hydrocarbons (TCE and PCE) and explosive compounds (TNT, RDX, and HMX) in underground water using a pulsed-UV system. Crystallized cells containing the contaminants were placed 10, 20, and 40 cm away from a lamp that emits pulsed-UV rays in order to examine how the removal efficiency is influenced by the distance between the source of the light and the compounds. Chlorinated hydrocarbons were completely removed in 30 minutes with a distance of 10 cm, while PCE was completely removed even with a distance of 20 cm. In the case of explosive compounds, removal efficiencies slightly varied depending on the compounds. The majority of the compounds were perfectly removed with a contact time of 10 minutes. In particular, for RDX, the results showed that complete removal was obtained within one minute, regardless of the distance from the UV source. The amount of light energy is in inverse proportion to the distance, and thus the energy reaching the compounds severely diminishes as the distance increases. Therefore, the removal efficiency decreased with increasing distance in the system.

• Membrane and Water Treatment
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• 제13권2호
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• pp.85-95
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• 2022

Tetrachloroethylene (PCE) and trichloroethylene (TCE), critical pollutants to human health and groundwater ecosystems, are managed by groundwater quality standards (GQS) in South Korea. However, there are no GQSs for their by-products, such as cis-dichloroethylene (DCE) and vinyl chloride (VC) produced through the dechlorination process of PCE and TCE. Therefore, in this study, we monitored PCE, TCE, cis-DCE, and VC in 111 national groundwater wells for three years (2016 to 2018) to evaluate their distributions, a biological dechlorination possibility, and human risk assessment. The detection frequency of them was 30.2% for PCE, 45.1% for TCE, 43.9% for cis-DCE and 13.4% for VC. The four chlorinated compounds were commonly detected in 21 out of 111 wells. In the results of statistical analysis with 21 wells data, DO and ORP also had a negative correlation with four organic chlorinated compounds, while EC and sulfate has a positive correlation with the compounds. This indicates that the 21 wells were relatively met with suitable environments for a biological dechlorination reaction compared to the other wells. Finally, cis-DCE had a non-carcinogenic risk of 10^-1 and the carcinogenic risk of VC was 10^-6 or higher. Through this study, the distribution status of the four chlorinated compounds in groundwater in South Korea and the necessity of preparing plans to manage cis-DCE and VC were confirmed.

• 한국물환경학회지
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• 제24권1호
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• pp.118-122
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• 2008

Degradations of phenol and chlorinated compounds mixtures were studied with ultrasound of 20 kHz and 0.57, 1.14 W/mL. In presence of carbon tetrachloride (CT), degradation rate of phenol is faster than chloroform (CF), dichloromethane (DCM) and phenol solution. It is due to that CT generates of free chlorine (HOCl and $OCl^-$) from the sonochemical degradation and plays a role of hydrogen atom scavenger. CF and DCM are react with free chlorine, so amount of free chlorine is smaller than CT solution. The degradation rates of chlorinated compounds decreased with co-presence of phenol in the solution due to the distribution ultrasonic energy to both compounds. The measured chloride ion was lower than the theoretical concentration assuming complete degradation. This means not all the contaminants destructed went through complete degradation.