• Proceedings of the Korea Air Pollution Research Association Conference
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• 한국대기환경학회 2002년도 추계학술대회 논문집
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• pp.417-418
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• 2002

열분해는 독성이 강한 염화탄화수소의 처리뿐만 아니라 염화물을 효과적으로 제거하여 이들로부터 유용한 탄화수소를 얻을 수 있는 반응이다 Biomass에 열분해를 적용하여 가스상, 액상, 고상형태의 유동한 부산물로 전환시키고 있으며 현재 액상생성물은 외국에서 큰 주목을 받고 있는 부산물이다. 1,1,2-trichloroethane(TCE)는 독성이 강한 휘발성 유기화합물(VOC)이며 발암물질이다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 한국대기환경학회 1992년도 제15회 대기보전학술연구발표회 요지집
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• pp.14-16
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• 1992

• Journal of Environmental Science International
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• 제5권5호
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• pp.569-577
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• 1996

pure compound chloromethanes; methyl chloride, methylene chloride, chloroform and The carbon tetrachloride were used as a model of chlorocarbon system with Cl/H ratio to investigate thermal stability and hydrodechlorination process of carbon tetrachloride under excess hydrogen atmosphere. The parent thermal stability on basis of temperature required for 99% destruction at 1 second no was evaluated as $875^{\circ}C$ for $CH_3Cl$, $780^{\circ}C$ for $CH_2Cl_2$, $675^{\circ}C$ for $CHCl_3$ and $635^{\circ}C$ for $CCl_4$. Chloroform was thermally less stable than $CCl_4$ at fairly low temperatures $(<570^{\circ}C).$ The lion of $CCl_4$ became more sensitive to increasing temperature, and $CCl_4$ was degraded CHCl3 at above $570^{\circ}C.$ The number and quantity of chlorinated products decreases with increasing temperature for the Product distribution of $CCl_4$ decomposition reaction system. Formation of non-chlorinated hydrocarbons such as $CH_4$, $C_2H_4$ and C_2H_6$ increased as the temperature rise and particularly small amount of methyl chloride was observed above $850^{\circ}C$ in $CC1_4$/$H_2$ reaction system. The less chlorinated products are more stable, with methyl chloride the most stable chlorocarbon in this reaction system.

• Clean Technology
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• 제16권3호
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• pp.198-205
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• 2010

Two sets of thermal reaction experiment for chlorinated hydrocarbons were performed using an isothermal tubular-flow reactor in order to investigate thermal decomposition, including product distribution of chlorinated hydrocarbons. The effects of $H_2$ or Ar as the reaction atmosphere on the thermal decomposition and product distribution for dichloromethane($CH_2Cl_2$) was examined. The experimental results showed that higher conversion of $CH_2Cl_2$ was obtained under $H_2$ atmosphere than under Ar atmosphere. This phenomenon indicates that reactive-gas $H_2$ reaction atmosphere was found to accelerate $CH_2Cl_2$ decomposition. The $H_2$ plays a key role in acceleration of $CH_2Cl_2$ decomposition and formation of dechlorinated light hydrocarbons, while reducing PAH and soot formation through hydrodechlorination process. It was also observed that $CH_3Cl,\;CH_4,\;C_2H_6,\;C_2H_4$ and HCl in $CH_2Cl_2/H_2$ reaction system were the major products with some minor products including chloroethylenes. The $CH_2Cl_2$/Ar reaction system gives poor carbon material balance above reaction temperature of $750^{\circ}C$. Chloroethylenes and soot were found to be the major products and small amounts of $CH_3Cl$ and $C_2H_2$ were formed above $750^{\circ}C$ in $CH_2Cl_2$/Ar. The thermal decomposition reactions of chloroform($CHCl_3$) with argon reaction atmosphere in the absence or the presence of $CH_4$ were carried out using the same tubular flow reactor. The slower $CH_3Cl$ decay occurred when $CH_4$ was added to $CH_3Cl$/Ar reaction system. This is because :$CCl_2$ diradicals that had been produced from $CHCl_3$ unimolecular dissociation reacted with $CH_4$. It appears that the added $CH_4$ worked as the :$CCl_2$ scavenger in the $CHCl_3$ decomposition process. The product distributions for $CHCl_3$ pyrolysis under argon bath gas were distinctly different for the two cases: one with $CH_4$ and the other without $CH_4$. The important pyrolytic reaction pathways to describe the important features of reagent decay and intermediate product distributions, based upon thermochemistry and kinetic principles, were proposed in this study.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 한국환경독성학회 2001년도 춘계심포지움 및 학술발표회
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• pp.36-41
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• 2001

환경변화 모니터링을 위한 지표생물로서의 척추동물의 중요성 생태계 에너지피라미드(energy pyamid)에서는 영양단계가 한 단계 올라갈 때마다 포식자들은 섭취한 먹이량의 약 90%를 생활에 필요한 호흡과 생리작용을 통해 소비하고 단지 10% 정도만이 다음 영양단계로 올라간다고 알려져 있다(Brum et al 1994). 그러나 염화탄화수소와 같은 오염물질들의 생체내에서의 대사효율은 다른 먹이의 약 20%에 불과하여 결국 50% 정도가 다음 단계의 소비자에게 전달되게 되는 셈이다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 한국대기환경학회 2000년도 추계학술대회 논문집
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• pp.245-246
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• 2000

산업의 발달로 인하여 유해폐기물의 양과 종류가 날로 증가하고 있다. 특히 본 연구에서 사용한 $CCl_4$는 염화탄화수소(chlorinated hydrocarbons, CHCs)(Elizabeth 와 Catherine) 계통의 대표적인 유해폐기물이며 플라스틱제조업, 제초제와 살충제를 제조하는 농약제조업, 유기용제 제조업 등에서 다량 배출되며 해마다 발생량이 증가하는 추세이다. 최근까지 대부분의 유해폐기물을 처리가격의 저렴성과 기술적으로 어려움이 적은 매립 및 밀봉등의 방법과 물리화학적 방법으로 처리하였으나 앞으로는 소각에 의한 처리방법이 증가되리라 예상된다. (중략)

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 한국안전학회 2002년도 춘계 학술논문발표회 논문집
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• pp.433-438
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• 2002

화재 및 폭발 특성치로 인화점, 최소발화온도, 폭발한계, 최소발화에너지, 연소열 등을 들 수 있다 이 가운데 폭발한계(explosive limits)는 가연성물질(가스 및 증기)을 다루는 공정 설계 시 고려해야 할 중요한 변수로써, 발화원이 존재할 때 가연성가스와 공기가 혼합하여 일정 농도범위 내에서만 연소가 이루어지는 혼합범위를 말한다/sup 1)/. 특히 폭발범위는 온도, 압력, 불활성가스의 농도, 화임전과 방향, 용기의 크기, 무리리적 상태 등에 의해 변한다/sup 2)/.(중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 한국대기환경학회 1999년도 추계학술대회 논문집
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• pp.94-95
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• 1999

불소나 염소가 수소대신에 치환 되어있는 활로겐화 화합물인 염화불화탄화수소(CFCs chlorofluoro carbons)는 오존층 파괴물질 그리고 지구온난화 기체물질로 널리 알려져있다. 이러한 CFCs는 Mauna Loa, Niwot Ridge, South Pole과 같은 지구배경농도지역에서 70년대 후반부터 지속적으로 측정되어 오고 있다. 대기중 CFCs농도는 일반적으로 수백 ppt 수준으로 매우낮아 측정이 매우 어려운 것으로 알려져왔다.(중략)

• Journal of the Korean Chemical Society
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• 제23권6호
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• pp.392-395
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• 1979

Some alkyl or aryl halides, such as ethyl bromide, butyl chloride, phenyl bromide and benzyl chloride, were reacted by Grignard's method with anhydrous tin tetrachloride in hydrocarbon media. When small amounts of ether were added into the Grignard reaction step, the reaction proceeded rather smoothly and gave good yields of corresponding organotin compounds.

• Journal of Korean Society of Environmental Engineers
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• 제30권7호
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• pp.735-742
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• 2008

In order to evaluate the levels and distribution patterns, the concentrations of PAHs and chlorophenols were investigated in sludge samples discharged from 6 WWTPs located along Nak-dong river and 7 STPs in Busan, Korea. Levels of 16 PAHs and 19 chlorophenols in sludge samples ranged from 1.28 to 44.9 mg/kg dry wt. and from 213 to 3,850 $\mu$g/kg dry wt., respectively. Levels of PAHs in sludge samples except I5 and S4 were detected lower than those of previous studies. The distribution patterns of PAHs and chlorophenols varied with industrial wastewater sludge samples because industrial wastewater sludge had different industrial input sources. However, the distribution patterns of PAHs and chlorophenols in sewage sludge were pretty similar. Phenanthrene, fluoranthene and pyrene were dominant and the fractions of these 3 PAHs relative to 16 PAHs in sewage sludge ranged from 30.8 to 50.7%. 2-chlorophenol is dominated in most sewage sludge samples and the fraction ranged from 36.0 to 66.8%.