• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.11a
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• pp.255-256
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• 2000

휘발성 유기화합물(Volatile Organic Compounds : VOCs)은 각종 산업체에서 많이 사용되고 있는 용매와 화학 및 제약공장 플라스틱의 건조공정에서 배출되는 유기가스 등까지 매우 다양하며, 저비점 액체연료, 파라핀, 올레핀, 방향족 화합물등 우리 생활주변에서 흔하게 사용되는 탄화수소류들이 거의 VOCs이다. 이러한 VOCs를 제어하기 위하여 폭넓은 제어기술의 연구 및 개발이 진행되고 있다. (중략)

• Journal of the Korean Chemical Society
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• v.25 no.3
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• pp.172-176
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• 1981

The formation of $C_2-C_{10}$ hydrocarbons from methanol over shape-selective ZSM-5 zeolite catalysts is studied. It seems that $C_2-C_5$ olefins formed from methanol via dimethylether are transformed further to higher hydrocarbons containing higher concentration of aromatics by the acid sites of ZSM-5. Unique cross linked channel structure and its hydrophobicity seems to be mainly responsible for its high activity of ZSM-5 catalyst for the conversion of methanol.

• Journal of the Korean Society for Marine Environment & Energy
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• v.12 no.2
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• pp.68-74
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• 2009

Polycyclic aromatic hydrocarbons (PAHs), one of ubiquitous organic pollutants in marine environments, are major toxic components of petroleum and are produced during the incomplete combustion of organic materials. As shipyards are located inside of natural or artificial semi-enclosed bay, even a relatively weak environmental disturbance by ship-building activity can cause severe damage to marine ecosystem in the bay. Many studies of pollution in shipyard area have been focused on the antifouling agent, like tributyltin. This study aimed to investigate the effect of ship-building activity on PAH contamination. Total PAHs concentration was higher nearby and inside shipyard area than outside, implying that shipyard could be one of major source area of PAH contamination to pose harmful effects to surrounding environments. Through PAH profile and source recognition index, the source of PAHs inputs in this area was estimated to originate from both petrogenic and pyrogenic origin. PAH levels showed a significant correlation with total butyltins, indicating that ship-building activity influenced PAH concentration and distribution. Vertical distribution of PAHs historically confirmed the correlation between shipbuilding activity and PAHs contamination.

• Applied Chemistry for Engineering
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• v.28 no.4
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• pp.467-472
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• 2017

In this study, the reforming reaction of vacuum residue (VR) was carried out using aquathermolysis reaction. VR showed a prone to decrease the amount of resins and asphaltenes in the constituents, and to increase saturates and aromatics when reacting with steam at 30 bar and above $300^{\circ}C$ for 24 h. This tendency became more evident when the amount of steam used was excessive than the amount of VR. When the aquathermolysis reaction was performed at $300^{\circ}C$ and 30 bar for 48 h, the VR composition was changed from the initial state (S/A/R/A = 7.3%/43.7%/25.6%/23.5%) to final state (S/A/R/A = 6.8%/57%/12.2%/24.0%), and the contents of the resins decreased by 13% and the aromatic compounds increased by 13%. The viscosity decreased from 880,000 cp to 290,000 cp by 68%. When 10% of decalin, which is easy to provide hydrogen, was added, the viscosity decreased by 68% in 24 h. The VR composition showed a reduction in the contents of resins and asphaltenes from 49% to 17% from the initial state (S/A/R/A = 7.3%/43.7%/25.6%/23.5%) to the final state (S/A/R/A = 4.5%/63.5%/12.5%/20.0%), and the content of aromatics was maximized to 63.5%. The gas layer formed by the aquathermolysis reaction in the reactor chamber was collected and analyzed by GC-MS spectroscopy. As a result, various hydrocarbon compounds such as ethylbenzene, octane and dimethylbenzene were detected.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.167-168
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• 2003

광화학 스모그는 대기 중으로 배출된 일차 오염물질인 /NO$_{x}$와 휘발성 유기화합물(volatile organic compounds)이 햇빛에 의해 반응하여 오존과 그외 다른 광화학 물질들을(photochemical oxidants) 생성시키는 현상이다. 서울의 경우 이런 VOCs 중에서 가장 많은 양을 차지하는 톨루엔은 광화학 반응을 통해 이차 유기 에어로졸(secondary organic aerosols)을 생성하는 능력이 매우 높은 방향족 화합물이다(Na and Kim, 2001). 지금까지 톨루엔의 이차 유기 에어로졸 생성에 관한 연구와 다른 방향족 탄화수소에 관한 연구가 스모그 챔버 실험을 통해 많이 이루어져 왔다. (중략)

• Analytical Science and Technology
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• v.25 no.6
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• pp.467-475
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• 2012

A gas chromatography-mass spectrometric (GC-MS) method was developed for determining 17 hazard compounds containing phenols, polycyclic aromatic hydrocarbons and pesticides in surface water. A 1.0 L surface water sample was placed in a separatory funnel and saturated with NaCl, and the solution was extracted with 40 mL of methylene chloride. Under the established condition, the lowest quantification limit was 1.0-10 ng/L and the relative standard deviations were less than 22%. The method was used to analyze 70 surface water samples collected from 35 regions in Gum-River. The samples revealed the compounds concentrations in the range of 1.1-26,604 ng/L. Maximum concentrations of compounds detected were not exceeded guidelines established in other countries. The developed method may be valuable for monitoring hazards in water.

• The Journal of Engineering Geology
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• v.13 no.4
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• pp.389-404
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• 2003

VOCs were detected in the 21 groundwaters out of 37 groundwaters sampled from around the Hanam Industrial Complex and the Gwangju stream. Ten components of chlorinated aliphatic hydrocarbons of VOCs were detected in the 18 groundwater samples. Among them, total trihalomethanes (TTHM) concentration is in the range of $0.1~36.2{\;}\mu\textrm{g}/L$, CECs concentration is $2.3~190{\;}\mu\textrm{g}/L$, and chlorinated solvents concentration containing PCE, TCE, etc. is $0.1~124.2{\;}\mu\textrm{g}/L$ respectively. Ten components of the aromatic hydrocarbons of VOCs were detected in the 5 groundwater samples, but their concentration are less than $1{\;}\mu\textrm{g}/L$. Detection frequency and concentration of the chlorinated aliphatic hydrocarbons components from the groundwaters in the Hanam Industrial Complex are higher than those of nearby downtown Gwangju stream. VOCs components except for TCE are lower than the MCL of USGS drinking water standard. TCE concentration of the 2 groundwater samples is over MCL, whose concentrations are 5 and 25 times higher than MCL, respectively. TCE is detected from the H8 and H10 groundwater samples and CFCs is detected H8 and H11 groundwater samples in the Hanam Industrial Complex. TTHM in study area is estimated from leakage of the main waters or sewage waters. Because most of the studied groundwater is under an aerobic condition, aromatic hydrocarbons are well degraded. But chlorinated aliphatic hydrocarbons are degraded very slowly.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.323-324
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• 1999

비오염 전원지역 (remote rural)과 해안지역 (marine)은 도심과는 달리 직접적인 인위적 휘발성 유기 화합물의 배출원이 없거나 적은 곳이다. 이러한 특성은 장거리 이동되는 오염원의 발생지를 추적하거나 이동 특성을 연구하는데 도움이 된다. 또한 오염지역에서의 농도 수준을 결정하거나 농도 특성을 연구하는데 있어서 비오염 지역의 배경농도는 중요한 의미를 갖는다.(중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2001.11a
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• pp.37-38
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• 2001

Polycyclic Aromatic Hydrocarbons(다환방향족 탄화수소류, 이하 PAHs)는 두 개 이상의 벤젠 고리로 구성되어 있는 반휘발성 유기물질로서 가스상과 입자상에 모두 존재한다. PAHs는 주로 불완전 연소에 의해서 생성되며, 주요 고정 오염원은 주거 난방, 코크 산업, 소각이고, 주요 이동오염원은 자동차 엔진이다. PAHs에는 강한 발암성 혹은 돌연변이원성을 가진 화합물들이 포함되어 있고, 주변 대기에 널리 분포되어 있을 가능성이 높기 때문에 일반 대중이 쉽게 노출될 수 있다. (중략)

• Proceedings of the Korean Fiber Society Conference
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• 1996.10a
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• pp.124-130
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• 1996

The hydrocarbons containing more than 10 carbons(0.1% of total volume, C10+), residue of aromatization from aliphatic hydrocarbons, were condensated in the presence of catalyst aluminumchloride and cocatalyst nitrobenzene(NB) to be pitchs with desirable properties. The properties of pitch were affected by the concentration of cocatalyst chosen 20 and 30wt.%. The pitch with 30wt.% NB showed higher carbon yield and lower crystallinity than that with 20wt.% NB. The two pitches were heat treated at 1000C and measured of charge/discharge capacity of the carbon as an anode. The carbon prepared at 20wt.% NB exhibited excellent cyclic stability with a capacity of 218mAh/.g and that at 30wt.% exhibited rather low cyclic stability with higher capacity of 235mAh/g.