• Journal of Microbiology and Biotechnology
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• 제3권1호
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• pp.46-50
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• 1993

In 12:12 hour light/dark cycle cultivation of D. salina 1650, maximum specific growth rate of 0.59 (l/day) and 0.35 (g-crude hydrocarbons/l/day) were obtained. The cell growth was inhibited at above 15$\times$$10^{-4} (kcal/cm^2/h)$ of light intensity in an outdoor cultivation. It was also showed that temperature is one of the critical growth parameters in the outdoor cultivation. The hydrocarbon production from D. salina 1650 seems to be partially growth related production process, and these algal hydrocarbons can be used for subsituting petroleum directly or through cracking processes. The value of weight fraction carbon of D. salina 1650 was similar to that of Botryococcus braunii and so was the hydrocarbon productivity.

• Korean Chemical Engineering Research
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• 제57권4호
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• pp.565-574
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• 2019

Fischer-Tropsch 합성공정은 합성가스로부터 탄화수소를 합성하는 대표적인 방법이며, 주로 철(Fe)계와 코발트(Co)계 촉매로 알려져 있다. 현재 생성물에 따라 일부 기술(CTL, GTL 등)은 상용 규모로 운전되고 있으나, 경질탄화수소와 중간유분을 직접 생산하는 연구는 아직 상용화되지는 않았다. 그러므로, 본 연구에서는 국내에서 현재까지 경질탄화수소와 중간유분을 직접 생산하기 위한 연구들을 정리하였으며, 촉매의 제조법, 조촉매 첨가, 제올라이트의 조합과 같은 영향이 생성물의 선택도에 미치는 영향을 고찰하였다.

• 한국수소및신에너지학회논문집
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• 제35권1호
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• pp.27-33
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• 2024

In this study, we researched Ni-based bead catalysts for the catalytic thermal decomposition of light hydrocarbons. A Ni-based bead-type catalyst was prepared, and catalytic thermal decomposition performance of light hydrocarbons was evaluated. The 30Ni/Al₂O₃ catalyst exhibited the most superior performance, with the presence of both fibrous and carbon black forms on the catalyst surface. Catalytic performance was evaluated for particles sized between 150-250 and 500 ㎛, with excellent catalytic thermal decomposition properties in the 150-250 ㎛ range. After the reaction, carbon removal through collision between catalysts in the fluidized bed was observed. It was confirmed that as the particle size increases, the amount of carbon removed increases.

• 한국환경보건학회지
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• 제24권2호
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• pp.74-79
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• 1998

본 실험은 light hydrocarbon에 오염된 토양을 용매 추출할 때 계면활성제의 영향을 평가하고자 6가지의 계면활성제 (Witbreak DPG-482, Witbreak DRA-22, Witcomul 4016, Witcolate SL-1, Adsee 799, Triton X-100)와 2가지 용매(물, 메타놀)를 대상으로 실험하였다. Light hydrocarbon으로는 benzene, toluene, ethyl bnzene, o-xylene, m-xylene, p-xylene, n-propyl benzene, 1,2,4-trimethyl benzene, 그리고 n-butyl benzene등 9가지를 대상으로 하였다. 계면활성제중 Adsee-799과 Witbreadk DRA-22가 토양중 light hydrocarbon의 물추출 효율을 다소 증가시키는 것으로 나타나고 있으며, 나머지 계면활성제는 효과가 없었다. 또한 물중의 계면활성제의 농도가 0.5%이하에서는 효과가 없는 것으로 나타나고 있으며, 계면활성제의 농도가 4%일때 평균 10.8%의 추출증가 효과가 있었다. 메타놀을 추출용매로 사용할 때에는 Witbread DPG-782와 Witbreak DRA-22가 약 10%의 추출증가 효과를 나타내고 있었다.

• 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.

• 대한화학회지
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• 제55권5호
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• pp.824-829
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• 2011

In Fischer-Tropsch Synthesis, because of few reactants ($H_2$, CO), scarce operating parameters affected on efficiency especially the selectivity of products. In this research, effect of operating parameters on the selectivity of Co-Mn-$TiO_2$ Fischer-Tropsch synthesis catalyst were studied by design of experimental procedure and Taguchi method. According to this research, interactions between operating factors have a crucial effect on light products selectivity. Among these interactions, (temperature${\times}$feed ratio) has the main influence on light hydrocarbons selectivity. It was concluded that temperature and feed ratio ($H_2$/CO) were the most integral operating parameters for much greater selectivity of light hydrocarbons.

• Journal of Microbiology and Biotechnology
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• 제1권2호
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• pp.111-115
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• 1991

The green alga, Dunaliella salina under fed-batch cultivation produced 51.12 mg of hydrocarbon per liter with maintaining 0.313 (g dry wt/l). About 20% of hydrocarbon production yield based on dry biomass was obtained from both batch and fed-batch processes. Optimum culture conditions of light intensity, pH and salt concentration were obtained as 0.0080 (kJ/$cm^2$/h), 8.0 and 1.4 (g of NaCl/l), respectively by response surface analysis. The production of hydrocarbons in D. salina was closely correlated to cell growth. Fed-batch cultivation produced more hydrocarbons and maintained better cell growth than a batch process.

• 한국환경보건학회지
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• 제23권4호
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• pp.82-90
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• 1997

본 실험은 석유의 주요성분인 benzene, toluene, p,m,o-xylene, ethylbenzene, n-propylbenzene, 1,2,4-trimethylbenzene, n-butylbenzene 등 light hydrocarbon에 오염된 토양의 회복에 필요한 최적 용매추출 조건을 밝히기 위하여 실시하였다. 토양의 수분함량이 증가할수록 추출효율은 감소하였으며, Methanol을 용매로 사용하였을때에 BTEX화합물은 1시간 추출시 최고 추출효율에 도달하였으며 고분자 hydrocarbon은 4시간이상 추출시 최고 추출효율에 도달하였다. 2-Propanol을 추출용매로 사용할때는 모든 light hydrocarbon은 추출 4시간 경과시 최고의 추출효율을 나타냈다. 추출용매와 토양의 비율이 2:1일때 가장 경제적이고 효율적이고 추출이 이루어 졌으며, 0.4mg/g이상의 토양오염 농도에서 최적의 추출효과가 나타났다. 위의 최적조건으로 light hydrocarbon 오염토양을 batch extraction을 이용하여 추출하였을 때 평균 66%의 light hydrocarbon이 회수되었으며, 회수율은 토양의 종류, 추출용매의 종류 그리고 hydrocarbon의 종류에 따라 좌우되었다. 본 연구의 결과는 석유에 오염된 토양의 회복을 위한 토양세척에 사용될 수 있을 것으로 사료된다.

• 한국환경과학회지
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• 제27권11호
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• pp.967-974
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• 2018

In this study, we evaluated the photocatalytic oxidation efficiency of aromatic volatile hydrocarbons by using $WO_3$-doped $TiO_2$ nanotubes (WTNTs) under visible-light irradiation. One-dimensional WTNTs were synthesized by ultrasonic-assisted hydrothermal method and impregnation. XRD analysis revealed successful incorporation of $WO_3$ into $TiO_2$ nanotube (TNT) structures. UV-Vis spectra exhibited that the synthesized WTNT samples can be activated under visible light irradiation. FE-SEM and TEM images showed the one-dimensional structure of the prepared TNTs and WTNTs. The photocatalytic oxidation efficiencies of toluene, ethylbenzene, and o-xylene were higher using WTNT samples than undoped TNT. These results were explained based on the charge separation ability, adsorption capability, and light absorption of the sample photocatalysts. Among the different light sources, light-emitting-diodes (LEDs) are more highly energy-efficient than 8-W daylight used for the photocatalytic oxidation of toluene, ethylbenzene, and o-xylene, though the photocatalytic oxidation efficiency is higher for 8-W daylight.

• 한국연소학회지
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• 제4권2호
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• pp.23-33
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• 1999

A turbulent non-premixed ethylene flame, which was set up in a vertical wind tunnel, was examined to understand the effect of turbulent mixing on formations of soot and gaseous species in the flames. Temperature and velocity profiles were measured using uncoated thermocouples and LDV system. Gaseous samples were withdrawn by using a water cooled stainless iso-kinetic gas sampling probe. The samples for inorganic compounds and light hydrocarbons were collected with sampling bottles and were analyzed by a gas chromatography. The samples for aromatic hydrocarbons were collected on a sorbent tube and were analyzed on a GC/MS system. Some of main results were followed. CO and $CO_2$ were measured relatively in early part of flame and the concentration of CO was greater than that of $CO_2$ all over the early flame region due to the scavenging of the oxidizing species OH by soot particles. Aromatic hydrocarbons were measured at x/D=122 along the radial direction and main important species were benzene, xylene, toluene, styrene, indene, naphthalene. The peak points of these compounds occurred at r/D=0.8 apart from the center of flame, around in which the concentration of $C_2H_2$ decayed relatively rapidly from the maximum value.