• Applied Chemistry for Engineering
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• v.8 no.3
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• pp.357-364
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• 1997

The objective of this study was to find optimum nonionic surfactants for clean up of soils contaminated by hydrocarbon oils. PIT(phase inversion temperature) measurements in ternary systems containing pure hydrocarbons, pure nonionic surfactants, and water were carried out and interfacial tensions were measured as a function of time for n-hexadecane oil drops brought into contact with various mixtures of nonionic surfactant and water. Batch surfactant washing experiments were performed based on the measurement, results of PIT and interfacial tension and the results showed that maximum removal of n-hexadecane occurred at the PIT of the system. For the $C_{12}E_5(C_{12}H_{25}O(CH_2CH_2O)_5H)$ system, maximum n-hexadecane removal of 73.4% occurred at the PIT of $52^{\circ}C$. In contrast, n-hexadecane removal at $25^{\circ}C$ and at $60^{\circ}C$, each corresponding to the conditions of below PIT and above PIT of the system, was found to be 57.1% and 57.0% respectively. The maximum removal of a hydrocarbon at the PIT of a system, where the hydrophilic and hydrophobic properties are balanced, was found to be due to the existence of high oil solubilization into a middle-phase microemulsion and ultralow interfacial of the order of $10^{-2}$ to $10^{-3}$ dyne/cm between middle-phase microemulsion and excess oil phase.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.12
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• pp.2247-2254
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• 2000

This study was carried out to investigate the reaction characteristics of NOx with reagents to grope the power consumption rate reduction and NOx removal rate improvement for the non-thermal plasma denitrification process. The experiments were performed using the real flue gas and wire-plate type plasma reactor. and the flow rate of real flue gas is $20Nm^3/hr$. Paraffinic and olefinic hydrocarbons and ammonia were used as reagents. Olefinic hydrocarbon oxidizes NO more actively than paraffinic hydrocarbon under the non-thermal plasma conditions, resulting in the generation of large amount of $NO_2$ and a very small amount of CO. When the initial NOx concentration increases. oxidation rate of NO decreases and the consumption rate of olefinic hydrocarbon increases significantly. On the other hand. $NH_3$ did not promote reduction reaction with NO under non-thermal plasma conditions. however, there was a tendency that the NHa was effective to remove the $NO_2$ oxidized by olefinic hydrocarbon.

• Korean Chemical Engineering Research
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• v.52 no.2
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• pp.219-225
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• 2014

In this study, effect of cosurfactant on the solubilization rate of n-octane, n-decane and n-dodecane oil was performed by micellar solutions of polymeric nonionic surfactant Pluronic L64($EO_{13}PO_{30}EO_{13}$) at room temperature. It has been found that the solubilization rate of a hydrocarbon oil was enhanced with an increase in both chain length and amount of alcohol added. In case of addition of a short chain alcohol such as 1-butanol, the solubilization rate of a hydrocarbon oil was slightly increased since most of alcohol molecules remained in an aqueous surfactant solution. On the other hand, the addition of a relatively long chain alcohol such as 1-hexanol and 1-octanol produced a big increase in solubilization rate of a hydrocarbon oil mainly due to incorporation of alcohol molecules into micelles and thus producing more flexible micellar packing density. Dynamic interfacial tension measurements showed the same trend found in solubilization rate measurement. Both interfacial tension value at equilibrium and time required to reach equilibrium decreased with an increase in chain length of an alcohol.

• Applied Chemistry for Engineering
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• v.20 no.5
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• pp.473-478
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• 2009

Phase equilibrium and dynamic behavior studies were performed on systems containing $C_{10}E_5$ nonionic surfactant solutions and nonpolar hydrocarbon oils. The phase behavior showed an oil in water (O/W) microemulsion (${\mu}E$) in equilibrium with excess oil phase at low temperatures and a water in oil (W/O) ${\mu}E$ in equilibrium with excess water phase at high temperatures. For intermediate temperatures a three-phase region containing excess water, excess oil, and a middle-phase microemulsion was observed and the transition temperature was found to increase with an increase in the chain length of a hydrocarbon oil. Dynamic behavior at low temperatures showed that an oil drop size decreased linearly with time due to solubilization into micelles and the solubilization rate decreased with an increase in the chain length of a hydrocarbon oil. On the other hand, both spontaneous emulsification of water into oil phase and expansion of oil drop were observed because of diffusion of surfactant and water into oil phase. Under conditions of a 3 phase region including a middle-phase ${\mu}E$, both rapid solubilization and emulsification of oil into aqueous solutions were found mainly due to the existence of ultra-low interfacial tension. Interfacial tensions were measured as a function of time for n-decane oil drops brought into contact with 1 wt% surfactant solution at $25^{\circ}C$. Both equilibrium interfacial tension and equilibration time increased with an increase in the chain length of a hydrocarbon oil.

• Journal of Life Science
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• v.21 no.11
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• pp.1599-1606
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• 2011

To evaluate the effects of microorganism agents on oil biodegradation, treatability and microcosm studies were conducted. Petroleum oil degrading bacteria were isolated from enriched cultures of oil-contaminated sediment samples using a mineral salts medium (MSM) containing 0.5% Arabian heavy crude oil as the sole carbon source. After a 5 day-incubation period using MSM, mixed microorganisms of three species (strains BS1, BS2 and BS4) degraded 48.4% of aliphatic hydrocarbons and 30.5% of aromatic hydrocarbons. Treatability and microcosm tests were performed in the three different treatment conditions (AO: Arabian heavy crude oil, AO+IN: Arabian heavy crude oil+inorganic nutrient, AO+IN+MM: Arabian heavy crude oil+inorganic nutrient+mixed microorganism agents). Among these, significantly enhanced biodegradation of aliphatic hydrocarbons were observed in AO+IN and AO+IN+MM conditions, without showing any different biodegradation rates in either condition. However, the degradation rates of aromatic hydrocarbons in an AO+IN+MM condition were increased by 50% in the treatability test and by 13% in the microcosm test compared to those in an AO+IN condition. Taken together, it can be concluded that mixed microorganism agents enhance the biodegradation of aliphatic and aromatic hydrocarbons in laboratory, a treatability test, and a microcosm test. This agent could especially be a useful tool in the application of bioremediation for removal of aromatic hydrocarbons.

• Geophysics and Geophysical Exploration
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• v.9 no.2
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• pp.163-170
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• 2006

The shortage of proven hydrocarbon reserves has resulted in exploration progressing from the offshore into progressively deeper water of the continental shelf. Despite the success of seismic acquisition at ever greater depths, there are marine geological terrenes in which the interpretation of seismic data is difficult, such regions dominated by scattering or high reflectivity that is characteristic of carbonate reefs, volcanic cover and submarine permafrost. A marine controlled-source electromagnetic (CSEM) method has recently been applied to the oil and gas exploration thanks to its high-resistivity characteristics of the hydrocarbon. In particular, this method produces better results in terms of sensitivity under the deep water environment rather than the shallow water. Only in the last five years has the relevance of CSEM been recognized by oil companies who now use it to help them make exploration drilling decisions. Initial results are most promising and several contractors now offer magnetotelluric and CSEM services.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.114.2-114.2
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• 2010

Fisher-Tropsch 반응을 통하여 생성되는 왁스는 황 또는 질소 성분을 포함하지 않으며 또한 방향족 및 중금속 성분이 없기 때문에 청정 수송유로써 사용이 가능하다는 장점이 있다. 그러나 Fisher-Tropsch 왁스는 그 분자량이 매우 큰 사슬형 탄화수소이기 때문에 수소첨가 분해반응을 통하여 중질유 range의 탄소수를 갖는 탄화수소로의 전환 기술이 반드시 필요하다. 이러한 수소첨가 분해반응에 사용되는 촉매는 강한 산점을 지니고 있는 양이온 교환 지르코니아가 대표적이라 할 수 있는데 최근 들어 강한 산점과 높은 산밀도, 그리고 기공의 모양과 크기에 따라 특정 반응이 제어되거나 활성화되는 형상선택성을 가지고 있기 때문에 다양한 반응에 촉매로 사용되는 제올라이트에 Pt 등의 귀금속을 담지한 촉매를 사용하여 Fisher-Tropsch 왁스의 전환율 및 중질유분의 선택도를 높이는 기술에 대한 연구가 활발히 진행되고 있다. 따라서 본 연구에서는 다양한 제올라이트 촉매에 귀금속을 담지하여 촉매를 제조하고 1L 급 고압 배치형 반응기를 이용하여 Fisher-Tropsch 왁스의 수소첨가 분해반응에 의한 중질유 제조 실험을 수행하고 그 결과를 고찰하였다.

• Applied Chemistry for Engineering
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• v.1 no.1
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• pp.100-105
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• 1990

Small amounts of potassium were added to the titania - supported cobalt catalysts in order to produce higher and olefinic hydrocarbons in CO hydrogenation. Titania and potassium played important roles not only for the enhancement of the production of higher and olefinic hydrocarbons, but also for the prevention of the catalyst deactivation by carbon deposits. Titania support induced the so - called SMSI, and potassium seemed to act as an electronic modifier, giving rise to an electron enrichment of the metallic phase.

• Proceedings of the KIEE Conference
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• summer
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• pp.602-603
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• 2004

전력용 변압기에 아크나 코로나가 발생하여 국부가열이 존재하면 절연유나 절연지가 분해하여 저분자의 탄화수소, 수소, 탄화가스, 일산화탄소 둥이 발생하여 절연유에 용해된다. 절연유에 용해된 가스를 실시간 분석하여 변압기의 이상을 조기에 발견하여 운전의 효율성을 높이고 고장을 사전에 예방하기 위한 기술이 전개되고 있다. 경제적인 측면에서 단일 수소가스 검출센서가 널리 보급되어 실용화되고 있는 실증이다. 이 논문에서는 전력용 변압기의 국부적 고온인 경우의 가열온도, 가열시간 및 방전에 대하여 수소가스 주도형 센서의 응답특성에 관하여 고찰하였다.

• 월간산업보건
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• s.71
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• pp.22-30
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• 1994