• Korean Chemical Engineering Research
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• 제46권5호
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• pp.965-970
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• 2008

접촉분해경유의 산화반응후 포함된 산화황화합물을 분리하기위해 다양한 용매를 사용하여 용매추출에 관한 연구를 수행하였다. 용매로는 극성을 가진 물, N-메틸피놀리논, 에틸아세테이트, 디메틸포름아마이드, 이소프로필알코올, 아세토니트릴, 메탄올등을 사용하였다. 실험결과, 접촉분해경유와 용매와의 층분리는 적절한 양의 물을 첨가한 경우에 이루어졌으며, 물과 N-메틸피놀리논을 혼합한 혼합용매가 접촉분해경유로부터 산화황화합물의 선택적인 분리에 가장 적절하였다. 또한 접촉분해경유로부터 황화합물을 99.5% 이상으로 제거하기 위해선, 4단 정도의 평형추출이 필요하였다.

• 한국산업보건학회지
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• 제26권3호
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• pp.307-316
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• 2016

Objectives: In general, NIOSH method 5506 is most widely used for the occupational exposure measurement of PAHs, but 2-4 ring PAHs have poor desorption efficiency, especially for a filter. The purpose of this study was to determine a method to increase the desorption efficiency of 16-PAHs using an ultrasonic extraction procedure. Methods: Test samples prepared spiked XAD-2 tubes and PTFE filters in the range of $0.01-1.0{\mu}g/mL$ for desorption efficiency study. Four different extraction solvents, acetonitrile, acetone, tetrahydrofuran and dichloromethane, were tested in order to select the most suitable solvent for the extraction of the 16 PAHs. The addition of dimethyl sulfoxide and sonication time were considered in order to determine the method with the highest extraction efficiency. All samples were made in three sets and analysis was replicated seven times by HPLC. Results: Acetonitrile and acetone were the optimized as an extraction solvent and desorption efficiency of 2-ring PAHs such as naphthalene, acenaphthylene were increased 3~19% with dimethyl sulfoxide for XAD-2. Acetone was the best extraction solvent for PTFE filter and the desorption efficiency was increased 3~13% for 2- to 4-ring PAHs. The optimum sonication time was 60 minutes and desorption efficiency increased with extraction time. Conclusions: As a result, the best extraction solvent was acetone with dimethyl sulfoxide for ultrasonic extraction procedure and the desorption efficiency of this method was better than NIOSH 5506's. This study could be applied as a method for occupational exposure measurement of PAHs.

• Food Science and Biotechnology
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• 제18권4호
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• pp.996-1000
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• 2009

Sapium japonicum was extracted by a pressurized liquid. Operating parameters such as the type and the ratio of solvent to water, temperature, pressure, and number of extractions were investigated as the main variables that influence the extraction efficiencies of total phenolics (TP). MeOH extracted the highest level of TP as 50.4 mg GAE/g compared to 48.8 and 27.2 mg GAE/g with $H_2O$ and EtOH, respectively. $EtOH:H_2O$ (40:60, v/v) was found to be the best solvent for TP extraction as 90.3 mg GAE/g compared to 85.0 and 84.3 mg GAE/g in 40:60 and 60:40 of $MeOH:H_2O$, respectively. TP were increased with the increase of the number of extraction steps. TP content was increased by 11% as the extraction temperature was increased from 40 (97.4) to $50{\circ}C$ (108.3 mg GAE/g). The optimum extraction conditions of TP were; extraction solvent, $EtOH:H_2O$ (40:60, v/v); temperature, $50{\circ}C$; pressure, 10.2 MPa; 2 extraction steps.

• 한국군사과학기술학회지
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• 제9권3호
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• pp.123-131
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• 2006

This paper reports the apparatus and method for the safe treatment of pentachlorophenol(PCP)-treated ammunition box by solvent extraction. Experimental variables were chosen as the composition of solvents, types of substance(chips and sawdust), temperatures and sonication to obtain maximum PCP removal from wood samples of the dismantled ammunition box. Up to 99% of PCP in the wood chip was extracted within 2 hours at room temperature when using methanol as the solvent. The extraction volume ratio of methanol per dried sample was about 10. Type of samples, extraction temperature and sonification showed little effects on PCP extraction. Based on this study, a resource recycling system for the treatment of ammunition boxes was recommended.

• Biotechnology and Bioprocess Engineering:BBE
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• 제9권3호
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• pp.207-211
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• 2004

Predispersed solvent extraction (PDSE) of succinic acid with Tri-n-octylamine (TOA) dissolved in 1-octanol from aqueous solutions of 50 g/L succinic acid was examined. It was found that the equilibrium data in PDSE was equal to that in conventional solvent extraction in spite of the lack of mechanical mixing in PDSE. The influence of salts on succinic acid extraction and the stability of colloidal liquid aphrons (CLAs) were also investigated. Results indicated that in the presence of sodium chloride, less succinic acid was extracted by CLAs and the stability of CLAs decreased. However, the stability of CLAs was sufficient to make PDSE practically applicable to real fermentation broth, considering the concentration range of salts in the fermentation process for succinic acid.

• Natural Product Sciences
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• 제19권2호
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• pp.166-172
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• 2013

Caffeine and epigallocatechin gallate (EGCG) are major constituents of green tea, the leaves of Camellia sinensis (Theaceae). Although EGCG is well known for diverse beneficial effect, caffeine is sometimes harmful with adverse effects. Therefore, the extraction efficiency was investigated using different extraction method such as extraction solvent, extraction time, extraction method, and repeated extraction. The content of EGCG and caffeine in green tea extract was quantitated by HPLC analysis. The extraction condition exerted difference on the extraction yield. The content of EGCG was also affected by different extraction condition. Especially, the extraction solvent greatly affected the content of EGCG in the extract. However, the content of caffeine was less affected compared to that of EGCG. The inhibitory effect of green tea extract on pancreatic lipase was almost similar regardless of extraction condition. Taken together, optimization of extraction condition will provide best efficacy for further development of green tea as anti-obesity therapeutics.

• Bulletin of the Korean Chemical Society
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• 제23권10호
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• pp.1381-1391
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• 2002

The solvent sublation using ion pairs of metal-2-naphthoate(2-HNph) and tetrabutyl ammonium ($TBA^+$) ion has been studied for the concentration and determination of ultra trace Bi(III), In(III) and Tl(Ⅲ) ions in water samples. The partition coefficients ($K_p$) and the extraction percentages of 2-HNph and the ion pairs to methyl isobutyl ketone (MIBK) were obtained as basic data. After the ion pair $TBA^+$·M$(Nph)_4^-$ was formed in water samples, the analytes were concentrated by the solvent sublation and the elements were determined by GF-AAS. The pH of the sample solution, the amount of the ligand and counter ion added and stirring time were optimized for the efficient formation of the ion pair. The type and amount of optimum surfactant, bubbling time with nitrogen and the type of solvent were investigated for the solvent sublation as well. 10.0 mL of 0.1 M 2-HNph and 2.0 mL of 0.1 M $TBA^+$ were added to a 1.0 L sample solution at pH 5.0. After 2.0 mL of 0.2%(w/v) Triton X-100 was added, the ion pairs were extracted into 20.0 mL MIBK in a flotation cell by bubbling. The analytes were determined by a calibration curve method with measured absorbances in MIBK, and the recovery was 80-120%.

• 한국응용과학기술학회지
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• 제41권2호
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• pp.520-529
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• 2024

Lycium barbarum extract has a high potential to be developed as a health functional food due to the various health-promoting effects of Lycium barbarum. This study analyzed changes in nutritional and functional components depending on the extraction solvent (purified water and a mixture of purified water and alcohol) and the condition of the sample. The nutritional components (carbohydrates, protein, fat, ash), organic acids, amino acids, total phenolic compounds, and total flavonoids of the extract produced during the extraction process were analyzed. The nutritional composition and functional substances of the extracts showed some differences depending on the type of solvent and the condition of the sample. The amounts of crude protein (7.61%), crude fat (1.63%), carbohydrate (90.22%), and ash (0.54%) of dried Lycium barbarum extract using purified water as a solvent were similar to those of the powder sample extract. The highest content of citric acid was 4.31 mg/mL, similar to the case of acetic acid, when the powder sample used a mixture of purified water and alcohol as a solvent. The highest amino acid content was 357.39 mg/mL when the powder sample was mixed with purified water and alcohol as a solvent. The total amount of phenolic compounds was 686.16 g/L when the powder sample was extracted with a mixture of purified water and alcohol as a solvent. The highest total flavonoid content was 111.32 g/L when the powder sample was extracted with a mixture of purified water and alcohol as a solvent.

• 폴리머
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• 제32권1호
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• pp.13-18
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• 2008

전기 전자재료 중 고분자에 포함된 브롬계 난연제의 분석에 있어 용출이 어려운 4가지 재질 PC(polycar-bonate) PP(polypropylene), PET(poly(ethylene terephthalate)), PBT(poly(butylene terephthalate))에 대하여 추출방법 및 헥산/에세톤, THF, 톨루엔, THF/톨루엔에 대한 용매 특이성과 그 특성을 고찰하였다. 각 고분자에서의 deca-BDE(decabromo diphenyl ether)의 함량을 속슬렛, 초음파. 가속용매, 마이크로파, 초임계 유체 추출법을 사용하여 이들 방법의 효율을 정량분석 하였다. 초음파 추출은 낮은 고분자의 용해도 때문에 낮은 추출효율을 보여 사용한 고분자의 경우에 있어서 추출방법으로는 적합하지 않았으며, 나머지 3가지 방법에서는 톨루엔 사용시 약 80% 이상의 높은 추출효율을 보였다. 초임계 유체 추출은 고분자의 난연제 추출에 시도되지 않았던 방법이었으나, 본 실험에서 PP와 PC의 추출에서는 100%에 가까운 매우 높은 추출효율을 보였다.

• KSBB Journal
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• 제23권4호
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• pp.281-284
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• 2008

본 연구에서는 식물세포배양액에서 회수한 식물세포인 biomass로부터 항암제 paclitaxel을 효율적으로 회수하기 위해, microwave를 이용한 추출 (MAE) 방법을 도입하여 기존의 유기용매 추출 (CSE) 방법과 추출효율을 비교하였다. CSE 방법에서 추출온도 25, $30^{\circ}C$에서는 추출시간 (3, 6, 10 min)에 대해 추출효율이 온도에 영향을 받지 않은 반면, 40, $50^{\circ}C$에서는 추출시간 10 min에서 paclitaxel 수율이 감소하는 경향을 보여 온도에 영향을 받음을 알 수 있었다. CSE 방법의 경우 총 4회의 추출로 식물세포 내 대부분의 paclitaxel을 회수 (>99%) 가능한 반면 MAE 방법의 경우 1회의 추출로 식물세포 내 대부분의 paclitaxel을 회수 (>99%) 가능하였다. MAE 방법이 CSE 방법보다 paclitaxel를 회수하는데 있어서 높은 추출효율, 공정시간 단축, 에너지 절감 효과가 있음을 알 수 있었다. 또한 MAE 공정에서 최적의 biomass/methanol의 비율은 1/1 (w/v)임을 알 수 있었다.