• Analytical Science and Technology
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• v.19 no.6
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• pp.455-459
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• 2006

The extraction and separation of glabridin from licorice root by HPLC was performed in this work. First, by investigating the different extraction solvents, extraction methods and extraction times, a one-hour ultrasonic extraction procedure with ethyl acetate as the extraction solvent was optimized. Then the ethyl acetate extraction was applied to RP-HPLC for separation of glabridin. The column efficiencies and resolutions were experimentally investigated with different mobile phase compositions. Baseline separation of glabridin was obtained under the mobile phase composition of 50/50 vol.% (ACN/water). The retention time of glabridin was 20.3 min. The peak of glabridin was collected from the HPLC elution for several times and identified by LC/MS. Under the optimum extraction and HPLC separation methods, 1.26 g of glabridin per kg licorice root could be extracted.

• Resources Recycling
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• v.14 no.2
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• pp.33-42
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• 2005

Solvent extraction experiments have been performed to separate Nd and Sm from chloride solution with PC88A. The effect of the saponification of PC88A on the extraction and separation of the two metals were studied. In the experimental ranges conducted in this study, the distribution coefficients of Sm were higher than those of Nd and separation factor between them increased with the equilibrium pH of aqueous solution. Saponification of PC88A enhanced the distribution coefficients of Sm and Nd and the separation factor. A chemical model was developed to predict the distribution coefficients of metals and separation factor from the initial extraction conditions. The measured distribution coefficients of Nd and Sm with PC88A and saponified PC88A agreed well with those calculated in this study.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.20 no.6
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• pp.307-313
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• 2010

Quantitative analytical condition for lead and cadmium in copper contained carbon materials using solvent extraction followed by inductively coupled plasma-atomic emission spectrometry was studied. Copper contained carbon samples were dissolved by nitric acid-perchloric acid digestion. Lead and cadmium were determined after separation with KCN masked copper by an dithizone-chloroform solvent extraction. Recovery efficiency of analyte elements was satisfactory, and most of matrix elements causing interference could be effectively eliminated by the separation. Lead and cadmium were quantitatively determined without influence of sample matrix, by applying it procedure to artifact sample.

• Analytical Science and Technology
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• v.6 no.1
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• pp.21-27
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• 1993

Technical grade n-hexane whose purity is 54% has been purified for HPLC use. Methylcyclopentane, 2-methylpentane, and 3-methylpentane which are hardly isolated by fractional distillation were separated by the liquid-solid chromatography using molecular sieve 5A. UV and fluorescence impurities whose contents are critically regulated for HPLC solvent were removed by the adsorptive separation with alumina and silica gel. The present method also reduced the impurities of color(APHA), acidity, water, residue after evaporation, sulfur, and thiophene content, and the impurity contents were well within the specifications of HPLC solvent.

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

• Environmental Analysis Health and Toxicology
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• v.12 no.3_4
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• pp.75-84
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• 1997

Chromatographic retention behavior and separation of various phenol derivatives on a Partisil 10 ODS 3 column-with mobile phase containing $\alpha$-cyclodextrin-were systematically studied. The decrease in k' values caused by the addition of cyclodextrins in the mobile phase was based on the formation of an inclusion complex, resulting in weakening of the hydrophobic interaction between solutes and the stationary phase. The content of the organic solvent in the mobile phase also influenced k' values of the solutes, and k' values increased with a decrease of the content of organic solvent in the mobile phase. A simple equation has been derived that reveals the hyperbolic dependence of the capacity factor on the total concentration of cyclodextrin. A plot of the reciprocal of the capacity factor against (CD)$_T$ gives a straight line and the dissociation constant, K$_D$, of the inclusion complex can be calculated from the slope. The capacity factor decreased with increasing temperature. The enthalpy was calculated from the slope of van't Hoff plots. Under optimum conditions, some mixtures of phenol derivatives were able to separated successfully.

• Journal of Integrative Natural Science
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• v.10 no.1
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• pp.43-50
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• 2017

Synthetic resins were combined 1-aza-12-crown-4 macrocyclic ligand with styrene divinylbenzene copolymer having 1%, 2%, 8%, and 16% crosslink by a substitution reaction. These synthetic resins were confirmed by chlorine content, elementary analysis, SEM, surface area, and IR-spectrum. As the results of the effects of pH, crosslink of synthetic resin, and dielectric constant of a solvent on metal ion adsorption for resin adsorbent, the metal ions showed high adsorption at pH 3 or over. Adsorption selectivity for the resin in ethanol solvent was the order of uranium ($UO_2{^{2+}}$) > cobalt ($Co^{2+}$) > dysprosium ($Dy^{3+}$) ion, adsorbability of the metal ion was the crosslink in order of 1%, 2%, 8%, and 16% and it was increased with the lower dielectric constant. In addition, theses metal ions could be separated in the column with 1% crosslink resin by using nitric acid (pH 2.0) as an eluent.

• Clean Technology
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• v.24 no.1
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• pp.15-20
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• 2018

Hexafluoropropyleneoxide ($C_3F_6O$, HFPO) is highly expensive and it may be used as a raw material for the synthesis of various fluorine based compounds. Currently, extractive distillation method has gained considerable attention to collect the HFPO from a mixture of HFPO / hexafluoropropylene ($C_3F_6$, HFP). Optimized operating conditions are studied using a theoretical method for the extraction process. Among available solvents for the purification process, the use of 1,1-dichloro-1-fluoroethane exhibits a high purity of HFPO as a top product and minimize the required heat duty. Since the boiling point of the solvent increases as the pressure in the column increases, the enhanced extractive capability of the solvent led to the high purity of HFPO at the high pressure.

• Korean Journal of Metals and Materials
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• v.47 no.6
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• pp.349-355
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• 2009

In the solvent extraction of Ru(IV) with Alamine336, it was found that Ru took part in the reaction as $RuCl_{6}_^{2-}$ in the HCl concentration range of 1 to 5 M. Interaction parameter between hydrogen ion and $RuCl_{6}_^{2-}$ was estimated by applying Bromley equation to the extraction data. From the mixed solutions of Pd(II) and Ru(IV), the distribution coefficients of Pd were found to be higher than those of Ru in the experimental ranges. Separation factor between Pd and Ru rapidly increased with the decrease of Alamine336 concentration. About 60% of the Ru from the mixed solutions was extracted by TBP at 8.3 M HCl, while Pd was not extracted in the HCl concentration range of 1.6 to 8.3 M.

• Nuclear Engineering and Technology
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• v.55 no.2
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• pp.391-407
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• 2023

This article provides a survey of wet (aqueous) methods for recovery, separation, and purification of uranium from fission products in carbonate solutions during the reprocessing of spent nuclear fuel and methods for removal of radionuclides from alkaline radioactive waste. The main methods such as selective direct precipitation, ion exchange, and solvent extraction are considered. These methods were compared and evaluated for reprocessing of spent nuclear fuel in carbonate media according to novel alternative non-acidic methods and for treatment processes of alkaline radioactive waste.