• 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%.

• Resources Recycling
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• v.26 no.1
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• pp.37-42
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• 2017

It has been reported that aqueous indirect carbonation process of calcium silicate mineral could be one of the most promising methods for $CO_2$ sequestration. The process consists of two main steps, extraction of Ca from calcium silicate and carbonation of the extracted solution by $CO_2$. Many types of acids such as HCl and $HNO_3$ can be used in the extraction step of the process. In the case of using aqueous acetic acid solution as the extraction solvent, acetic acid can be reproduced at the carbonation step of the extracted solution by $CO_2$ and recycled to extraction step for reuse it. Industrial by-products such as iron and steel slags are potential raw materials of the indirect carbonation process due to their high contents of calcium silicate. In this study, in order to examine the extraction efficiency of domestic electric arc furnace steel slag by aqueous acetic acid solution, extraction experiments of the slag were performed by using the aqueous acetic acid solutions of varying extraction conditions ; acetic acid concentrations, extraction temperatures and times.

• Food Science and Biotechnology
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• v.14 no.1
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• pp.131-136
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• 2005

The selective extraction behavior of lactoferrin (Lf) from whey protein mixture was examined using reverse micelles formed by the cationic surfactant, cetyldimethylammonium bromide (CDAB). The major whey proteins, including ${\beta}$-lactoglobulin, ${\alpha}$-lactalbumin and bovine serum albumin, were solubilized from aqueous phase to organic phase while Lf was recovered in the aqueous phase. The solubilization behaviors of the proteins were manipulated by the process parameters such as the pH and salt concentration of the aqueous phase and the surfactant concentration in the organic phase. Efficient forward extraction was achieved with sodium borate buffer (50 mM, pH 9) containing 50 mM KCl and organic phase containing 100 mM CDAB. Based on SDS-PAGE and densitometry, about 96% of the initial Lf remained in the aqueous phase after forward extraction. The dialyzed Lf fully maintained its bacteriostatic activity against E. coli O157:H7.

• Journal of Institute of Convergence Technology
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• v.4 no.2
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• pp.23-26
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• 2014

As an effective separation method for biomolecules, aqueous two-phase systems based on ionic liquids were suggested. Hydrophobic ionic liquids are more expensive and viscous in spite of their usage in the ionic liquid/water biphasic extraction compared with hydrophilic ionic liquids. In case of aqueous two-phase systems using hydrophilic ionic liquids, they can be diluted in aqueous phase. Experimental results show that aqueous two phase systems can be formed by adding appropriate amount of ionic liquids to aqueous salts solutions. The viscosity of ionic liquid aqueous phase is proportional to the cation chain length in ionic liquids. It is founded that the ionic liquid based aqueous two phase systems are effective for the separation of biomolecules such as acrylic acid.

• Korean Journal of Food Science and Technology
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• v.23 no.6
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• pp.673-676
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• 1991

Lipids and protein were extracted simultaneously from soybean flour by aqeous processing. Extraction yields of lipids and protein were 62 and 68%, respectively, when 120-150 mesh full-fat soybean flour was dispersed in six times of water (w/w) at $40^{\circ}C$ and pH 8. Supplementary treatment for the higher extraction yields such as proteolytic enzymes treatment improved extraction yields of lipids and protein up to 86 and 89%, respectively. Ultrasonification also improved extraction yields of lipids and protein up to 90%. Red and yellow colors of aqeous-extracted soybean oil were slightly darker than those of hexane-extracted oil, but were much lighter in colors than those of Folch-extracted oil.

• Journal of Industrial and Engineering Chemistry
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• v.67
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• pp.109-122
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• 2018

This work highlights extraction and removal of Lignosulfonate using sunflower oil-Tri-n-octylamine (TOA) system in bulk liquid membrane transport. Maximum extraction and recovery percentages of 92.4% and 75.2% were achieved. Optimum manifold operating conditions were: 4 vol.% TOA, $2{\pm}0.1$ feed phase pH, 300 rpm stirring speed, at $40^{\circ}C$ with 0.2 (M) $Na_2SO_4$ solution. 1:2 (organic/aqueous) and 1:1 (aqueous/aqueous) phase ratios produced best results. Extraction (36.85 kJ/mol) was found to be intermediate controlled and stripping (54.79 kJ/mol) was chemical reaction controlled. Kinetic estimation of data with higher rate constants for stripping vis-${\grave{a}}$-vis extraction showed latter to be rate determining.

• Applied Chemistry for Engineering
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• v.9 no.7
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• pp.1036-1042
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• 1998

It was investigated that the extraction of Cr(VI) from aqueous solution into the organic TDA and the stripping(back extraction) of Cr(VI) from the Cr(VI)-TDA complex into NaOH aqueous solution by hydrophobic hollow fiber membrane. It was found that the mass transfer rates of stripping process were smaller than those of the extraction process. This result was expected that membrane resistance, neglected in the extraction process, acts on the stripping process when organic phase flow in the tube side of the hydrophobic membrane. Hollow fiber modules were made by potting the desired number(60, 100, 150, 300fibers). We also examined the effect of flow rates of aqueous and organic phase on the mass transfer rate in the membrane modules. From these experiments, we identified for the extraction process by using hydrophobic membrane, the effect of flow rate of aqueous phase on the mass transfer rate was significant, but that of organic phase was negligible one. In the stripping process, however, mass transfer rate depend neither flow rate of aqueous(stripping solution) phase nor that of organic(Cr-TDA complex) phase.

• Journal of Microbiology and Biotechnology
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• v.24 no.12
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• pp.1690-1698
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• 2014

Partial purification of glucoamylase from solid-state fermentation culture was, firstly, investigated by reverse micellar extraction (RME). To avoid back extraction problems, the glucoamylase was kept in the original aqueous phase, while the other undesired proteins/enzymes were moved to the reverse micellar organic phase. The individual and interaction effects of main factors (i.e., pH and NaCl concentration in the aqueous phase, and concentration of sodium bis-2-ethyl-hexyl-sulfosuccinate (AOT) in the organic phase) were studied using response surface methodology. The optimum conditions for the maximum recovery of the enzyme were pH 2.75, 100 mM NaCl, and 200 mM AOT. Furthermore, the optimum organic to aqueous volume ratio ($V_{org}/V_{aq}$) and appropriate number of sequential extraction stages were 2 and 3, respectively. Finally, 60% of the undesired enzymes including proteases and xylanases were removed from the aqueous phase, while 140% of glucoamylase activity was recovered in the aqueous phase and the purification factor of glucoamylase was found to be 3.0-fold.

• Fibers and Polymers
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• v.4 no.1
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• pp.27-31
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• 2003

A major concern in solvent extraction process is the loss of extractant into the aqueous phase due to its slight solubility in the aqueous phase. Similarly, in membrane extraction processes, extractant loss through extractant leakage from the membrane into the aqueous phase is also a concern. Several published membrane extraction studies using Aliquat 336 ai the extractant, have expressed this concern, but none has studied extractant leakage quantitatively. It is the authors' opinion that the extractant leakage should be considered at a technical parameter of a membrane. In our laboratory active progress has been made in using Aliquat 336 ‘entangled’ into the polymer membranes to remove heavy metal ions from wastewater samples. In this work, we studied the loss of Aliquat 336 from the point of view of its solubility in aqueous solutions. The results showed that the solubilities or Aliquat 3,36 in an aqueous phase acidified with 2 M HCI it about 0.1 g/100 m/ of the solution. This figure provides a useful guideline for evaluating the leakage of the Aliquatoat 336 extractant from the membranes.

• Korean Chemical Engineering Research
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• v.51 no.1
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• pp.53-57
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• 2013

For the purpose of development of the extraction process of lithium ion from concentrated water eliminated from desalination process, an experimental research on the solvent extraction of lithium ion from aqueous solutions was performed. The effects of operating parameters, such as concentration of extractant, ratio of extracting solution/aqueous solution, pH of aqueous solution, were examined. The effect of sodium chloride, the major component of sea water, was also examined. Lithium ion in aqueous solutions of pH=10.2~10.6 adjusted by ammonia solution was most effectively extracted by extracting solution composed of 0.02 M TTA and 0.04 M TOPO in kerosine. The addition of sodium chloride in lithium aqueous solution significantly interfered the extraction of lithium ion.