• Analytical Science and Technology
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• v.9 no.2
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• pp.168-178
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• 1996

Molecular structures of petroleum fractions(diesel fuel, bunker-C oil, lubricant base stocks) have been analyzed and compared in terms of the compositions (aromatics, naphtherucs, paraffinics), aromatics(benzene-nuclear and bonded alkyl groups), C2(methylene) carbon atoms % $C_{\alpha}$ and $C_{\beta}$ carbon stom % in alkyl groups and paraffins(branched and normal) by near-infrared and $^{13}C$-NMR spectroscopy.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.09a
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• pp.99-102
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• 2002

전기분해에 의한 부상현상을 이용하여 토양세정 후 발생되는 유출수 중의 유수를 분리하기 위한 적정 운전조건에 관하여 고찰하였다. 전압에 의한 유수분리 효율을 관찰한 결과, 전기분해 1시간 후 3V의 전압만으로도 88% 정도의 제거율을 나타내었으며 6V 이상의 전압에서는 90% 정도로 거의 비슷한 제거율을 나타내어 대부분의 에멀젼이 분리됨을 확인할 수 있었다. 동일조건에서는 전기분해 시간이 경과될 수록 분리효율이 향상되었으며, 전극 간격이 넓어질수록 같은 효율을 얻기 위해 소요되는 전압의 크기가 커짐을 알 수 있었다. 전기분해 시 양극에서는 OH$^{-}$의 방전으로 발생되는 산소에 의해 산화반응이 일어나며, 음극에서는 H$^{+}$가 방전되어 발생되는 수소에 의해 환원반응이 일어나며 미세한 기포가 형성된다. 유분의 부상분리 현상은 유분의 (-)charge와 전기분해에 의해서 발생되는 양이온의 결합으로 인한 중화반응 및 음극에서 발생되는 미세 수소기포로 인만 부상분리가 대부분을 차지하며, 전압 및 전기분해 시간이 증가하고 전극 간격이 좁을수록 음극에서 발생되는 미세기포의 양이 증가되어 부상효과가 크게 나타나는 것으로 판단된다. 전극 종류는 구리 > 알루미늄 > 철 > 티타늄 순으로 효율을 나타내었으며, 이는 양극으로 사용된 이러한 금속들의 전기전도도 차이에 의해 일어나는 현상으로 판단된다

• Proceedings of the Membrane Society of Korea Conference
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• 1997.04b
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• pp.43-44
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• 1997

세척제는 금속 표면에 도포되어 있는 왁스, 그리스, 방청유 등의 윤활유 및 금속 가공 중에 사용한 절삭유, 연마유 등의 유지성 물질을 제거하는 탈지 효과와 표면에 묻어 있는 오물을 제거하는 목적으로 우수한 세정력을 지니고 있다. 세척제는 현장의 세척조의 상태가 가동 시간이 길어짐에 따라 유분이 과포화하게 되고 한정된 계면활성제량 때문에 미처 Micelle을 형성하지 못한 광유중 일부는 에멀젼 내 Oil Drop 형태로 존재하고 나머지는 에멀젼층 위에 부유하게 된다. 따라서 세척제의 세정력을 유지하기 위하여는 주기적으로 세척액중의 유분을 제거하여야 한다. 본 연구에서는 한외여과막을 이용하여 세척수 중 존재하는 Oil 성분을 제거함으로써 세척수의 수명을 극대화시키고자 한다. 또한 한외여과시 동반되는 농도 분극화 현상을 줄이고 투과특성을 향상시키기 위하여 압축질소로 주기적으로 역세척하며 최적운전 조건을 확인하는데 있다.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.15 no.1
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• pp.63-70
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• 1989

• Proceedings of the Membrane Society of Korea Conference
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• 2002.07a
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• pp.47-57
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• 2002

• Journal of the Korean Society for Marine Environment & Energy
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• v.6 no.3
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• pp.45-53
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• 2003

Discharging untreated bilge to the ocean is a cause of marine pollution. In general, bilge water contains free and/or emulsified forms of oil. Free form of oil can easily be separated by gravimetric flotation and/or proper filtration processes. However, those simple physicochemical processes could not separate emulsified oil without adding proper chemicals. Electrolytic flotation is one of promising technologies able to fulfill the effluent standard requirement, which is below 15 ppm of oil content. In this research, Electrochemical process consisting of electrochemical flotation basin was studied for the treatment of emulsified oil. In order to estimate, the effectiveness of oil separation equipment influent concentration of oil and HRT(Hydraulic retention time) were considered. Also, lab-scale electrochemical process was designed and operated in the condition of various HRT, current density, and electrode gap. Through the research, following results were obtained. From the experiment of bench scale electrochemical treatment process, it was demonstrated that the emulsified oil was treated effectively and the removal efficiency of emulsified oil from wastewater was increased with HRT and current density.

• Korean Chemical Engineering Research
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• v.46 no.5
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• pp.845-851
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• 2008

Oxidative desulfurizaton of model sulfur compounds and Industrial diesel fuel(LCO; Light Cycle Oil) over Ti-grafted SBA-15 catalyst was studied in a batch reactor with tert-Butyl Hydroperoxide(TBHP) as oxidant. Effects of Ti loading, TBHP/Sulfur mole ratio, reaction temperature on ODS activity and kinetic parameters were investigated. Ti-grafted SBA-15 catalyst showed higher sulfur removal activity in the oxidative desulfurization reaction of refractory sulfur compounds(DBT and 4, 6-DMDBT) and LCO, suggesting that Ti-grafted SBA-15 catalyst could be a good candidate for ODS catalyst.

• Korean Chemical Engineering Research
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• v.46 no.4
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• pp.692-696
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• 2008

There is not much method of using C4 Raffinate III, despite having high olefin contents. The majority of the C4 Raffinate III have been converted into n-butane through hydrogenation, and sold as LPG. The C4 Raffinate III is rich 2-butenes with very low isobutene and isobutene contents. The 2-butenes are converted into 1-butene in the vicinity of thermodynamic equilibrium yield through positional isomerization with n-almumina catalyst calcinated at $400{\sim}600^{\circ}C$. The overall process is composed of isomerization-reactor, de-1-buteneizer to prepare the reactants and to enrich reactive products, and 1-butene column to product a high purity 1-butene. The production of 1-butene increases by 40~60 wt% with the selective positional isomerization from the existing separation method.

• Korean Chemical Engineering Research
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• v.57 no.4
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• pp.565-574
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• 2019

Fischer-Tropsch synthesis process is a typical method for synthesizing hydrocarbons from syngas and is mainly known as iron (Fe) and cobalt (Co) catalysts. Currently, some technologies such as CTL (Coal to Liquid) and GTL (Gas to Liquid) are operated on a commercial scale depending on the products, but the research to produce light hydrocarbons and middle distillates directly has not been commercialized. Therefore, in this study, domestic studies for direct production of light hydrocarbons and middle distillates are summarized and the effect of catalyst preparation, promoter addition, zeolite combination on product selectivity is investigated.

• Journal of Food Hygiene and Safety
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• v.20 no.3
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• pp.134-140
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• 2005

Boiling point and distillation range, melting range, and identification methods in general test method of Korea, Japan, Joint FAO/WHO Expert Committee of Food Additives (JECFA), and USA on chemical food additives were compared. Boiling point of propylene glycol was indicated as boiling point in Korea, distillate in Japan, distillation range in JECFA and USA, and its value was up to the standard. Distillation range of propionic acid was indicated as distillate in Korea and Japan, distillation range in JECFA and USA, and its value was up to the standard. There is no standard on distillation range of isopropyl alcohol in Japanese method. Test method of melting range on synthetic food additives was identical in all organizations, and there are 28 items to which this test method applies in Korean Food Additives Code. The standards on molting range of D-mannitol were different in various organizations, and in USA method there are no standards to which L-ascorbic acid, calciferol, and fumaric acid apply. Synthetic food additives performing the identification test were 251 items in Korean Food Additives Code, but there are no items to which manganese, glycerophosphate, bromate, thiosulfate, and bromide apply. Calcium benzoate was dissolved by heating in benzoate test and we could not identify the citrate in ferric citrate by method (2) of Korea and Japan. Identification test methods for ammonium, lactate, magnesium, copper, sulfate, phosphate, and zinc were identical in all organizations, and these could be identifed by current identification methods.