• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.2
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• pp.217-222
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• 1999

A squid viscera oil contains a high content of EPA, DHA, and other valuable polyunsaturated fatty acids. The extractions of squid viscera oil by supercritical carbon dioxide both with/without $3\%$ (v/v) ethanol were performed in a semicontinuous flow extractor at 8.3 to 13.8 MPa and 25 to $50^{\circ}C$. When ethanol was added to $SC-CO_2$, the extraction ratio of lipid increased. The extracts contained high content of unsaturated oils like DHA and EPA. The highest extraction yield of lipid from squid viscera oil extracted by supercritical carbon dioxide was obtained at 12.4 MPa and $40^{\circ}C$ with/without entrainer. The main fatty acids of squid viscera oil extracted by supercritical carbon dioxide were myristric acid (14:0), palmitic acid (16:0), palmitoleic acid (16:1), oleic acid (18:1), arachidic acid (20:0), eicosapentaenoic acid (20:5), and docosahaxaenoic acid (22:6).

• Environmental Mutagens and Carcinogens
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• v.26 no.4
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• pp.119-124
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• 2006

There are $10{\sim}30%$ polyphenol and $2{\sim}4%$ caffeine in green tea. Caffeine is a kind of alkaloid containing nitrogen which cause stimulation, impatience, headache, insomnia, low birth weight infant. Because of these negative effect, decaffeined beverage came out and decaffeined coffee already have a big market since 1970s. Having proving the physiologic functions of green tea, high consumption of coffee is shifting to green tea. Because of the carcinogenic effect of the organic solvents, decaffeine processing with supercritical carbon dioxide has industrialized and have an advantage in environment-friendly and minimized flavor loss. Decaffeined green tea using supercritical carbon dioxide is considered to be safe but there are not enough study. We investigated the chromosome aberration test with mammalian cell line, CHL. When the cells were treated with 5000, 2000, 1000 ${\mu}g/ml$ and compared with the negative controls, there were no significant(P>0.05) increased chromosome aberration. Same results was observed when adding S9 mixture or not. As a result, water extract of decaffeined green tea using supercritical carbon dioxide does not induce chromosome aberration.

• Korea-Australia Rheology Journal
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• v.18 no.2
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• pp.83-90
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• 2006

Supercritical carbon dioxide ($scCO_2$) has advantages of being incorporated in polymer with high solubility and of being recovered easily by depressurizing. $scCO_2$ reduces the viscosity of polymer melt and it is expected to be use as a plasticizing agent. In this work, we studied on the effect of $scCO_2$ on the rheological properties of polymer melts during extrusion process. Slit die attached to twin screw extruder was used to measure the viscosity of polymer melts plasticized by supercritical $CO_2$. A gas injection system was devised to accurately meter the supercritical $CO_2$ into the extruder barrel. Measurements of pressure drop within the die, confirmed the presence of a one phase mixture and a fully developed flow during the measurements. The viscosity measurement of polypropylene was performed at experimental conditions of various temperatures, pressures and $CO_2$ concentrations. We observed that melt viscosity of polymer was dramatically reduced by $CO_2$ addition.

• Clean Technology
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• v.24 no.1
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• pp.1-8
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• 2018

As the social demands for environmental pollution increase and regulations on the dyeing process wastewater are strengthened, supercritical dyeing process has been attracting attention as an alternative technology to reduce wastewater and energy consumption. In the supercritical dyeing process where carbon dioxide is used as a solvent instead of water as a solvent, there is no wastewater generated. The unfixed dyes can be reused later which makes the process environment-friendly. Also, after dyeing process, dried textiles can be obtained without additional drying process, which makes the process energy efficient. In this article, we have summarized the development of the supercritical dyeing process along with the research in Korea today and compared the principle of supercritical dyeing process with conventional dyeing process. To further explain the principle, studies of the distribution factor and mass transfer of dyes in supercritical carbon dioxide and fibers, as well as solubility between supercritical $CO_2$ and dyes are discussed. The dynamic behavior of dyes in supercritical dyeing apparatus and summary of the supercritical dyeing facilities developed around the world are also discussed. Finally, we suggest the direction of research and development for optimization of supercritical dyeing process and application to synthetic fibers and natural fibers except for polyester.

• Textile Coloration and Finishing
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• v.15 no.2
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• pp.93-101
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• 2003

To acquire dyeing ability on aramid(Nomex) spun yarn in supercritical fluid dyeing, supercritical fluid dying(SFD) machine of 3L scale was designed. C. I. Disperse Red 60 and Red 360 were used in this work. It was possible to increase dyeing ability and to get level dyeing of fiber by attaching assistance devices(controlling device of supercritical fluid, nozzle, cover of carrier, etc.) to SFD machine. Physical properties(tensile strength, elongation, shrinkage) of Nomex spun yam treated by SFD were not changed. K/S values of dyed Nomex spun yam with Red 360 were higher than that with Red 60 and color fastness of dyed Nomex spun yam by SFD was similar to that by conventional dyeing method.

• Proceedings of the KSME Conference
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• 2005.11a
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• pp.124.1-124.1
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• 2005

• Magazine of RCR
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• v.16 no.4
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• pp.37-43
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• 2021

• Proceedings of the Korean Nuclear Society Conference
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• 1999.05a
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• pp.336-336
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• 1999

• Proceedings of the Korean Fiber Society Conference
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• 2000.04a
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• pp.225-228
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• 2000

• Bulletin of the Korean Chemical Society
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• v.20 no.4
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• pp.405-407
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• 1999