• Title/Summary/Keyword: Supercritical Methanol

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Extraction of Genistein from Sophora flavescens with Supercritical Carbon Dioxide (초임계유체를 이용한 고삼으로부터 Genistein의 추출)

  • Han, Chang-Nam;Kang, Choon-Hyoung
    • Korean Chemical Engineering Research
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    • v.53 no.4
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    • pp.445-449
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    • 2015
  • This study was directed to finding an optimum extraction condition of genistein from the S. flavescens with supercritical carbon dioxide as a solvent. In this effort, effects of the extraction conditions including pressure, temperature and a co-solvent on the extraction efficiency were investigated. The aqueous ethanol and methanol solutions were used as co-solvents while the tested operating pressure and temperature ranges were from 200 bar to 300 bar and from 308.15 K to 323.15 K, respectively. The concentration of genistein was determined by means of HPLC equipped with a UV detector. From the results, it was observed that an increase in pressure led to the higher extraction efficiency. Further, methanol showed better performance as a co-slovent than ethanol. The DPPH radical scavenging activities were measured to compare antioxidant activities of S. flavescens extracts.

Influence of Reaction Parameters on Preparation of Biodiesel from Rapeseed Oil using Supercritical Methanol (초임계 메탄올을 이용한 유채유 바이오디젤 제조에 대한 반응인자들의 영향)

  • Lim, Seon-Muk;Shin, Hee-Yong;Oh, Sea Cheon;Bae, Seong-Youl
    • Applied Chemistry for Engineering
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    • v.21 no.2
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    • pp.174-177
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    • 2010
  • In this study, non-catalytic transesterification from rapeseed oil using supercritical methanol was carried out by varying the operation parameters such as temperature ($320{\sim}365{^{\circ}C}$), time (0~20 min), pressure (10~35 MPa), molar ratio of oil to methanol (1 : 15~60) and agitation speed (0~500 rpm). In order to evaluate the effects of reaction parameters on the content of fatty acid methyl esters (FAMEs), we carried out the study using a batch reactor. The content of FAMEs increased when the temperature increased. However, the content of FAMEs decreased with temperature above $335^{\circ}C$ and time above 5 min. The content of FAMEs increased with increasing the molar ratio of methanol to oil but the content of FAMEs was slightly affected by molar ratio of oil to methanol above 1 : 45 and pressure above 20 MPa. It was found that the agitation speed above 100 rpm slightly affected the content of FAMEs. The highest content of FAMEs in biodiesel (95%) was obtained under the reaction conditions: temperature of 335 ${^{\circ}C}$, time of 10 min, pressure of 20 MPa, molar ratio of 1 : 45 (oil to methanol) and agitation speed of 250 rpm.

Studies on the supercritical fluid extraction of taxol from yew tree (초임계 유체를 이용한 주목 수피로부터 taxol의 추출에 관한 연구)

  • 서정혁;조병관변상요김공환
    • KSBB Journal
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    • v.11 no.1
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    • pp.71-76
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    • 1996
  • Studies were carried out to examine some factors affecting the supercritical carbon dioxide extraction of taxol from the bark of Taxus cuspidata using a continuous packed bed extractor. The factors investigated in this study were pressure, temperature, volume of carbon dioxide, and co-solvent. It was found out that the amount of taxol extracted was not significantly affected by the operating pressure in the absence of a co-solvent although it increased by about 20% at 5500 psig. With $24\ell$ of carbon dioxide the saturated amount of taxol was extracted at 318K and 5500psig. Methanol was found to be the most effective co-solvent in terms of amount of taxol extracted among six different co-solvents used. When methanol was used as a co-solvent the effect of operating pressure became significant; approximately 50% increase in the amount of taxol extracted was observed at 3000 psig as compared to at 2500 or 3500psig. The optimum methanol concentration in supercritical fluid was 13% (w/w)at 308K, 3000psig.

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Extraction of Glycyrrhizic Acid from Licorice using Supercritical Carbon Dioxide/Aqueous Ethanol (초임계 이산화탄소/에탄올을 이용한 감초의 Glycyrrhizic acid 추출)

  • 김현석;김병용;이상윤;김우식;이은규;유종훈;임교빈
    • KSBB Journal
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    • v.18 no.5
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    • pp.347-351
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    • 2003
  • The extraction of glycyrrhizic acid from licorice using supercritical carbon dioxide (SCCO$_2$) was investigated with respect to the effects of extraction parameters such as the kind and amount of modifier, temperature, pressure, and extraction time. The conventional organic solvent extraction was also conducted for a quantitative comparison. The content of glycyrrhizic acid in crude extracts was analyzed by HPLC and the yield of glycyrrhizic acid was computed as a weight percent recovery. The optimal pressure and temperature for SCCO$_2$ extraction were found to be 40 MPa and 80$^{\circ}C$, respectively, when SCCO$_2$ was modified with 70% aqueous ethanol. Under the same pressure and temperature, the highest recovery was attained to be 104.57% in the first 60 min when the concentration of 60%, aqueous ethanol in SCCO$_2$ was 15%.

Supercritical $CO_2$ Extraction of Genistein from Soybean (초임계 $CO_2$를 이용한 대두 Genistein의 추출)

  • Bu, Seong-Jun;Byeon, Sang-Yo
    • KSBB Journal
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    • v.14 no.4
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    • pp.490-494
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    • 1999
  • This study was carried out to examine some factors affecting the supercritical carbon dioxide extraction of genistein from soybean. The factors investigated in this study were pressure, temperature, flow rate of carbon dioxide, and concentration of modifier. It was foumd out that genistein is not extracted in the absence of modifier. Ethanol was found to be more effective modifier than methanol. 70% of genistein was extracted at 35$^{\circ}C$, 300bar and ethanol 15% (w/v) as compared with the performances of organic solvent extraction.

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Effect of Additives on the Contents of Fatty Acid Methyl Esters of Biodiesel Fuel in the Transesterification of Palm oil with Supercritical Methanol (팜유로부터 바이오디젤 연료를 합성하는 초임계유체반응에서 지방산메틸에스테르의 함량에 미치는 첨가물의 영향)

  • Lee, Hong-shik;Choi, Joon-hyuk;Shin, Young Ho;Lim, Youngsub;Han, Chonghun;Kim, Hwayong;Lee, Youn-Woo
    • Korean Chemical Engineering Research
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    • v.46 no.4
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    • pp.747-751
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    • 2008
  • The effect of additives in the synthesis of biodiesel fuel using supercritical methanol was studied in order to examine the possibility of application of spent vegetable oil as a raw material, which has high contents of water or free fatty acid. The experiments were performed by varying the contents of water, free fatty acid or antioxidants respectively in a batch reactor. The contents of fatty acid methyl ester was analyzed by a gas chromatography. As the water contents increased, the contents of fatty acid methyl ester decreased, however, the decrease was very little compared with the alkaline and acid catalyst. The effect of the contents of free fatty acid, vitamin E, and ${\beta}$-carotene was negligible.

Synthesis of Dimethyl Carbonate from Methanol and Supercritical Carbon Dioxide over K2CO3/ZrO2 Catalysts (메탄올과 초임계 이산화탄소로부터 K2CO3/ZrO2 촉매를 이용한 디메틸카보네이트 (Dimethyl Carbonate) 합성)

  • Hong, Seung Tae;Park, Hyung Sang;Lim, Jong Sung;Yoo, Ki-Pung
    • Korean Chemical Engineering Research
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    • v.46 no.3
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    • pp.550-554
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    • 2008
  • The synthesis of dimethyl carbonate (DMC) from methanol and supercritical carbon dioxide over $K_2CO_3/ZrO_2$ catalysts have been studied. The catalysts were prepared by impregnating $ZrO_2$ with an aqueous $K_2CO_3$ solution. The optimum calcination temperature to disperse K species on the $ZrO_2$ surface was found to be 673 K. Monoclinic $ZrO_2$ was not active, as itself, for the DMC production. However, when the $K_2CO_3$ was impregnated on the $ZrO_2$, the catalytic performance was improved. Besides the catalyst, $CH_3I$ was used as a promoter. The $CH_3I$ promoter as well as the $K_2CO_3/ZrO_2$ catalyst was found to take an important role to improve the production of DMC. The optimum quantities for the catalyst and the promoter were estimated. The effect of the catalyst and the promoter for the DMC synthesis from methanol and supercritical carbon dioxide was investigated and the reaction mechanism was proposed.

Influence of Reaction Parameters on Preparation of Biodiesel from Palm Oil using Supercritical Methanol (초임계 메탄올을 이용한 팜유 바이오디젤 제조에 관한 반응인자들의 영향)

  • Ryu, Jae-Hun;Lee, Si-Hong;Shin, Hee-Yong;Bae, Seong-Youl
    • Korean Chemical Engineering Research
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    • v.47 no.5
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    • pp.651-654
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    • 2009
  • In this study, non-catalytic transesterification using supercritical methanol was performed for preparation of biodiesel from palm oil. In order to investigate the effects of reaction parameters such as molar ratio of methanol to oil(30:1~60:1), pressure(8~25 MPa), temperature($320{\sim}350^{\circ}C$), agitation speed(0~1,000 rpm) and time(0~20 min) on the content of fatty acid methyl esters(FAMEs), we carried out the study using a batch reactor. With increasing molar ratio of methanol to oil, the content of FAMEs increased. However, the content of FAMEs was little affected by molar ratio above 45 and pressure above 20 MPa. The content of FAMEs increased when the temperature increased. However, the content of FAMEs decreased with temperature above at $350^{\circ}C$ and with time above 5 min. It was found that the agitation speed above 500 rpm scarcely affected the content of FAMEs. The highest content of FAMEs in biodiesel(95%) was obtained under the reaction conditions: temperature of $335^{\circ}C$, pressure of 20 MPa, molar ratio of 45:1(methanol to palm oil), agitation speed of 500 rpm and time of 10 min.

Effects of Modifiers on the Supercritical $CO_{2}$ Extraction of Glycyrrhizin from Licorice and the Morphology of Licorice Tissue after Extraction

  • Kim Hyun Seok;Lee Sang Yun;Kim Byung Yong;Lee Eun Kyu;Ryu Jong Hoon;Lim Gio Bin
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.9 no.6
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    • pp.447-453
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    • 2004
  • Optimal conditions for the supercritical carbon dioxide $(scCO_{2})$ extraction of glycyr­rhizin from licorice (Glycyrrhiza glabra) were investigated, with an emphasis on the types and levels of modifiers. The morphology of the licorice tissue remaining after the $scCO_{2} $ extraction of glycyrrhizin was examined by scanning electron microscopy, coupled with measurements of ab­solute density. Conventional organic solvent extraction was also carried out for purpose of quantitative comparison. At 50 MPa and $60^{circ}C$ glycyrrhizin could not be extracted with pure $scCO_{2}$, while a considerable amount of glycyrrhizin was extracted when water was added to $scCO_{2}$ as a modifier. The highest recovery was found to be about $97\%$ when $70\%$ aqueous methanol was added to $scCO_{2}$ at a concentration of $15\%$. The optimal pressure and temperature for the supercritical fluid extraction of glycyrrhizin were observed to be 30 M Pa and $60^{circ}C$, respectively. Under these conditions, the percentage recovery of glycyrrhizin attained a maximum value of 102.67\pm$ $1.13\%$ within 60 min. Furthermore, in the case of $scCO_{2}$ modified with $70\%$ aqueous methanol, the licorice tissue obtained after extraction was found to be severely de­graded by excessive swelling, and the absolute density of the licorice residues was observed to be the highest.

Preparation of L-PLA Microparticles using Pure and Cosolvent-modified Supercritical Carbon Dioxide (순수 초임계 이산화탄소와 극성 공용매로 변형된 초임계 이산화탄소를 이용한 L-PLA 미세입자 제조)

  • 김재훈;이상윤;김병용;유종훈;임교빈
    • KSBB Journal
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    • v.18 no.5
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    • pp.385-392
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    • 2003
  • Biodegradable poly (L-lactide) (L-PLA) solution in methylene chloride was precipitated into microparticles by using supercritical carbon dioxide modified with polar cosolvents. The effects of the amount of polar cosolvents, solution concentration, temperature, and solution flow rate on the formation of microparticles were investigated. The mean particle size was found to increase with the increase of solution concentration and flow rate. It was also observed that the particle size not only increases but the size distribution also becomes less uniform as the temperature increases. The percent recovery of microparticles was found to be 30∼40% at all experimental conditions. The supercritical carbon dioxide modified with methanol and ethanol was employed to enhance the recovery, resulting in significant improvement up to about 80 and 70%, for methanol and ethanol, respectively. Furthermore, the mean diameter of L-PLA microparticles was found to be less than 1 $\mu\textrm{m}$ for both cosolvents.