• Korean Chemical Engineering Research
• /
• v.52 no.5
• /
• pp.627-631
• /
• 2014

As an effective method for extraction of acrylic acid, aqueous two-phase systems based on morpholinium ionic liquids were used in this study. Effects of the alkyl chain length of cation in morpholinium ionic liquids on phase diagram and extraction efficiencies were investigated. Experimental results show that aqueous two phase systems can be formed by adding appropriate amount of morpholinium ionic liquids to aqueous $K_2HPO_4$ solutions. It can be found that the ability of morpholinium ionic liquids for phase separation followed the order [HMMor][Br]>[OMMor][Br]>[BMMor][Br]>[EMMor][Br]. There was little difference between binodal curves of imidazolium ionic liquids and those of morpholinium ionic liquids. 50~90% of the extraction efficiency was observed for acrylic acid by aqueous two phase extraction of acrylic acid with morpholinium ionic liquids. It can be concluded that morpholinium ionic liquids/$K_2HPO_4$ were effective for aqueous two phases extraction of acrylic acid comparing to imidazolium ionic liquids/$K_2HPO_4$ systems because of their lower cost.

• Journal of Industrial Technology
• /
• v.19
• /
• pp.189-195
• /
• 1999

A study on the separation Cu, Ni, and Co was carried out using LIX 84 leachate, chelate extractant. For this test, artificial test solution was prepared by varing concentrations of Cu, Ni, Co, $(NH_4)_2CO_3$ and $(NH_4)_2SO_4$. It found that pH of the solution was very important factor for the separation of nickel from copper. The results showed that nickel was effectively extracted from copper by using LIX 84 at pH 1.0 to 1.2. The volume ration or organic to aqueous phases was 1.0. According to the McCabe-Thiele diagram, the extraction rate of copper was 99 percents at the equal ratio of organic to aqueous phase in three stages.

• Biotechnology and Bioprocess Engineering:BBE
• /
• v.9 no.6
• /
• pp.454-458
• /
• 2004

A study of the POSE (predispersed solvent extraction) for succinic acid by colloidalliq­uid aphrons was conducted. The organic phase contaning TOA (tri-n-octylamine) and 1-octanol permits a selective extraction of succinic acid from its aqueous solution. There was no difference of the extractability of POSE and that of conventional mixer-settler type extraction. Taking into account the no mechanical mixing in POSE, it was concluded that the POSE process is more adaptive than the conventional mixer-settler type extraction process. From mass transfer analysis at the various concentration of TOA in counter-current continuous operation, the concentration of TOA had no influence on the mass transfer coefficient. The loading values in continuous POSE were almost same as those in batch operation.

• Journal of the Korean Society of Safety
• /
• v.2 no.1
• /
• pp.17-29
• /
• 1987

The extraction mechanism of Zinc from aqueous solution with D2EHPA (Di-2-Ethylhexyl Phosphoric Acid) dissolved in Kerosene was studied by the single drop method. The effect of the concentrations of reactant species on the extraction rate, Zinc and hydrogen ion in the continuous phase and D2EHPA in the dispersed, was studied for the drop rise period by the experiment. Then a theoretical analysis on the basis of Handlos-Baron modle was carried out. It becomes clear that the extraction rate was controlled by the neutral complex forming reaction at the drop surface from both analysises. From effect of the concentrations of species on the reaction rate, the extraction rate at the drop surface is considered to be as follows. $${\gamma}_{pn}=9.42{\times}10^{-7}\;\frac{[Zn^{2+}][(HR)_2]^{3/2}}{[H^+]^{3/2}}$$

• KSBB Journal
• /
• v.15 no.6
• /
• pp.649-657
• /
• 2000

The factors affecting the back-extraction efficiency of Bovine Serum Albumin (BSA, Mw. 65kDa, pl 4.9) solubilized in an AOT reverse micellar solution, prepared by the injection method, to an excess aqueous phase were investigated. In particular, the effects of pH, the types of salts, alcohols added as cosurfactants, and their concentrations in the aqueous phase were examined. Furthermore, by comparing the CD spectra of the back-extracted BSA and the feed BSA, the structural changes of BSA during the extraction process were determined. The addition of 1:1 salt such as KCl or NaCl to the aqueous phase resulted in almost a 100% extraction to the aqueous phase at a pH higher than its isoelectric point pl. This high efficiency of back-extraction might be due to the change in the interactions between the protein and micellar aggregates driven by the added salt. For 1:2 salts like $CaCl_2$ and $MgCl_2$, BSA was back-extracted with lower than 20% extraction efficiency. Maximum extraction efficiencies were attained at about pH=7 and pH=8 for monovalent and divalent salts, respectively. The addition of alcohols as cosurfactants led to an improvement in monovalent and divalent salts, respectively. From the CD spectra of BSA extracted to the aqueous phase, it was observed that denaturation of BSA was not significant. In certain back-extraction conditions, the extracted BSA showed even higher activity than the feed BSA.

• KSBB Journal
• /
• v.16 no.3
• /
• pp.241-245
• /
• 2001

Mass transfer rates have been measured for the extraction of enzyme from aqueous solution into a reverse-micelle phase at $25^{\circ}C$. The 420 mL vessel was carefully designed to maintain a planar interface between the aqueous and solvent phases, so allowing precise measurement of interfacial area, has been investigated. Sodium di-2-ethylhexyl sulfosuccinate(AOT) was the surfactant used. Factors varied included: agitator speed, pH, ionic strength and surfactant concentration. Samples were taken from the solvent phase at 15min intervals, and the amount of enzyme extracted was measured by UV absorption at 280 nm. The observed Sherwood numbers for the aqueous phase $Sh_1$were correlated interms of the aqueous phase Reynolds number $Re_1$, and modified Schmidt number $Sc_1$. $Sh_1=0.664Re_1^{0.5}Sc_1^{0.33}$

• Resources Recycling
• /
• v.26 no.5
• /
• pp.3-11
• /
• 2017

Solvent extraction is an important process to recover pure gold and silver from various leaching solutions. The present work reviews the aqueous chemistry and solvent extraction separation of gold (I, III) and silver (I) from several leaching systems such as cyanide, thiocyanate, thiosulfate, thiourea and chloride medium. The extraction and separation behavior of gold (I, III) and silver (I) by various single and mixtures was compared on the basis of extraction reaction and the selectivity from these mediums. The chloride medium is recommended for the separation of gold and silver by solvent extraction in terms of extraction and stripping efficiency.

• Fashion & Textile Research Journal
• /
• v.8 no.4
• /
• pp.465-470
• /
• 2006

Walnut hull is a by-product from the Walnut tree, used as natural dyestuff from ancient times. This study was done to examine the effects of extractive conditions on the properties of walnut hull extracts for making efficient use of the walnut hull as a natural colorant. Aqueous extracts of walnut hull were prepared at various extractive concentration, temperature and time. Then they were characterized using UV-Vis. Spectrophotometer, FT-IR Spectrometer, Prep Liquid Chromatography, and Energy dispersive X-ray spectrometer. The aqueous extracts have two absorbency peaks of UV-Vis. Spectrum, shoulder type peak in the range of 270-280 nm and broad type band around 420 nm. Intensity of absorbency is increased with increase of extraction concentration and time. However, Boiling temperature extraction method showed the most efficiency of all. Intensity of absorbency is also affected by extraction pH. The Prep LC examined two kinds of isolated colorant with different molecular weight. FT-IR spectra of hull extracts showed an absorption band around $3400cm^{-1}$, the peaks at $1700-1600cm^{-1}$, which are characteristic of aromatic compounds with unsaturated ketone and benzene ring. It showed that the extraction contained some mineral ions, such as K, Ca, Si, Mg.

• Food Science and Biotechnology
• /
• v.14 no.1
• /
• pp.6-10
• /
• 2005

Optimal extraction conditions such as pressures, temperatures, and modifiers on glycyrrhizin extraction from licorice were investigated using supercritical $CO_2\;(SC-CO_2)$ at 3 mL/min flow rate. Morphology of licorice tissue, after glycyrrhizin extraction, was examined by SEM, and absolute density ($g/cm^3$) measurement and glycyrrhizin content were determined by HPLC. Pure $SC-CO_2$ had no effect on glycyrrhizin extraction, but recovery of glycyrrhizin ($32.66{\pm}0.77%$) was enhanced when water was used as modifier. The highest recovery was $97.22{\pm}2.17%$ when 70% (v/v) aqueous methanol was added to 15% (v/v) $SC-CO_2$ at 50 MPa and $60^{\circ}C$. Under optimal extraction conditions, 30 MPa pressure and $60^{\circ}C$ heating temperature, glycyrrhizin recovery reached maximum ($102.67{\pm}1.13%$) within 60 min. Licorice tissue was severely damaged by excessive swelling, and absolute density of licorice residues was highest when aqueous methanol was used as a modifier.

• Resources Recycling
• /
• v.29 no.6
• /
• pp.79-87
• /
• 2020

The extraction and stripping of HCl from aqueous solutions by commercial extractants like LIX 63 and its mixture with TEHA/ Cyanex 923/ Aliquat 336 and ionic liquids like ALi-SCN, ALi-PC in kerosene was investigated. Among these extractants, ALi-PC showed the best extraction effectivity (above 80%), but it was difficult to strip HCl from the loaded phase. Although the extraction percentage of HCl by LIX 63 was not high, the stripping performance was above 81%. The addition of octanol to the organic phase led to negative effect on the extraction performance of HCl. The addition of C2H5OH into aqueous solutions significantly increased the extraction and stripping percentage of HCl by LIX 63, ALi-PC and ALi-SCN.