• Journal of the Mineralogical Society of Korea
• /
• v.30 no.4
• /
• pp.205-217
• /
• 2017

Mineral carbonation by indirect method has been studied by serpentinite as cation source. Through the carbonation of $CO_2$ and alkaline earth ions (calcium and magnesium) from serpentinite, the pure carbonates including $MgCO_3$ and $CaCO_3$ were synthesized. The extraction solvent used to extract magnesium (Mg) was ammonium sulfate ($(NH_4)_2SO_4$), and the investigated experimental factors were the concentration of $(NH_4)_2SO_4$, reaction temperature, and ratio of serpentinite to the extraction solvent. From this study, the Mg extraction efficiency of approximately 80 wt% was obtained under the conditions of 2 M $(NH_4)_2SO_4$, $300^{\circ}C$, and a ratio of 5 g of serpentinite/75 mL of extraction solvent. The Mg extraction efficiency was proportional to the concentration and reaction temperature. $NH_3$ produced from the Mg extraction of serpentinite was used as a pH swing agent for carbonation to increase the pH value. About 1.78 M of $NH_3$ as the form of $NH_4{^+}$ was recovered after Mg extraction from serpentinite. And, the main step in Mg extraction process of serpentinite was estimated by geochemical modeling.

• Food Engineering Progress
• /
• v.14 no.2
• /
• pp.92-98
• /
• 2010

In this study, various active functional components in Chinese Quince were extracted by solvent extraction method. A central composit design for optimization was applied to investigate the effects of independent variables such as solvent to sample ratio ($X_{1}$), extraction temperature ($X_{2}$), and extraction time ($X_{3}$) on the soluble solid contents ($Y_{1}$), total phenols ($Y_{2}$), electron donating ability ($Y_{3}$), browning color ($Y_{4}$) and reducing sugar contents ($Y_{5}$). It was found that extraction temperature and extraction time were the main effective factors in this extraction process. The maximum soluble solid contents of 35.77% was obtained at 26.38 mL/g ($X_{1}$), 72.82$^{\circ}C$ ($X_{2}$) and 74.86 min ($X_{3}$) in saddle point. Total phenols were rarely affected by solvent ratio and extraction time, but it was affected by extraction temperature. The maximum total phenols of 20.70% was obtained at 22.61 mL/g ($X_{1}$), 84.49$^{\circ}C$ ($X_{2}$), 77.25 min ($X_{3}$) in saddle point. The electron donating ability was affected by extraction time. The maximum electron donating ability of 94.12% was obtained at 10.65 mL/g ($X_{1}$), 67.78$^{\circ}C$ ($X_{2}$), 96.75 min ($X_{3}$) in saddle point. The maximum browning color of 0.32% was obtained at 23.77 mL/g ($X_{1}$), 87.27$^{\circ}C$ ($X_{2}$), 96.68 min ($X_{3}$) in saddle point. The maximum value of reducing sugar content of 10.55% was obtained at 26.83 mL/g ($X_{1}$), 82.167$^{\circ}C$ ($X_{2}$), 81.94 min ($X_{3}$). Reducing sugar content was affected by extraction time.

• Proceedings of the Korean Radioactive Waste Society Conference
• /
• 2008.05a
• /
• pp.87-88
• /
• 2008

• Food Science and Preservation
• /
• v.13 no.2
• /
• pp.216-222
• /
• 2006

Microwave energy (2450 MHz) was applied to extract health-effective component (HEC) from grape seed. Three different solvents approved for grape seed extract such as water, ethanol and acetone, were confirmed in their microwave-heating properties and by which extraction efficiencies were determined. Microwave-assisted extraction (MAE) was performed under different parameters; microwave power : (0, 50, 100 and 150), time : (1, 3, 5, 7, and 9 min), the sample to solvent ratio : (1:20, 1:10, 1:5 and 1:2.5), and particle size(whole, 20, 40 and 60 mesh) and the subsequent extracts were used for determining their physicochemical properties, such as total yield : (TY), total phenolics : (TP), catechin content : (CC), electron donating ability : (EDA), and browning color. The heating properties of solvent demonstrated the optimal ranges of microwave and time as 100 W and 2 to 6 min. The TY and HFC content were higher with increasing powers in water and ethanol solvent, while HFC content were lower in acetone at over 100 W. The longer of extraction time up to 5 min, the higher extraction efficiency. Based upon the overall MAE efficiency and solvent recovery, it was found optimal to use 10 times volume of ethanol for 10 mesh of seed particle at 100 W.

• Food Science and Preservation
• /
• v.12 no.1
• /
• pp.62-67
• /
• 2005

Microwave-assisted extraction (50 W, 2,450 MHz, MAE) with properties of selective heating and subsequent extraction for certain phytochemicals from natural materials was applied to pre-establish the extraction conditions for total yield total phenolics, and electron donating ability (EDA) from Brossica oleacea. The experiments with $50\%$ EtOH solvent showed that 20 mesh in particle size of cabbage flake $(moisture\;4.5\%)$ and 1:10 (g/mL) in the sample to solvent ratio for both raw $(moisture\;90.2\%)$ and flake cabbages were optimal for MAE efficiency. Under these conditions, total yield increased with extraction tim, which was highest for raw cabbage extract in $50\%\;EtOH$ solvent followed by $100\%\;EtOH$ and water. While that of flake cabbage extracts was highest in $50\%\;EtOH$ followed by water and $100\%\;EtOH$. The contents of total phenolics and EDA in extracts gradually increased after 3 min of MAE, which were highest when using $100\%\;EtOH$ solvent followed by $50\%\;EtOH$ and water in raw cabbage and $50\%\;EtOH$ followed by water and $100\%\;EtOH$ in flake cabbage, respectively.

• Resources Recycling
• /
• v.25 no.1
• /
• pp.60-67
• /
• 2016

A scale-up test with a continuous solvent extraction and electro-winning system was carried out to separate and recover copper from a synthetic sulfuric acid solution (Cu 10.5 g/L, Co 2.0 g/L, Ni 15.0 g/L, Fe 0.2 g/L). The solution was introduced into mixer-settlers with four stages of extraction and two stages of stripping for continuous countercurrent solvent extraction to separate copper from nickel and cobalt. The loading was carried out using 40% LIX 84-I(v/v) as extractant with a phase ratio of A : O = 1 : 1. Meanwhile, the stripping was undertaken at a phase ratio of A : O = 1 : 1.5 using depleted electrolyte containing 35.0 g/L Cu and 180 g/L $H_2SO_4$ as stripping solution. The extraction and stripping efficiencies were found to be 96.7% and 91.0%, respectively. The copper composition of the stripped solution (pregnant electrolyte) was 50.0 g/L Cu with impurities of 25 ppm nickel, 5 ppm cobalt and 3 ppm iron. In the electro-winning process, copper metal of 99.833 purity was yielded with current efficiency of 98.9% and current density of $1.50A/dm^2$.

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

• Polymer(Korea)
• /
• v.25 no.2
• /
• pp.151-160
• /
• 2001

Polymeric membranes consisting of poly(d,1-lactide) as a polymer matrix and crystallizable progesterone as a drug were prepared by coagulating polymeric solutions. The homogeneous casting solutions in dimethyformamide were solidified by using three different coagulating processes : solvent evaporation under vacuum, solvent extraction via immersion into the nonsolvent bath, or vapor exposure at high humidity condition. With solvent removal via evaporation under vacuum, the cast solution film was vitrified to form a homogeneous film containing progesterone of spherical shape distributed evenly in the film. Being prepared by solvent extraction via immersion into a water bath, the resulting membrane showed an asymmetric structure, with progesterone of big crystallites distributed unevenly in the structure. On the other hand, the coagulation under high humidity transformed the cast film into a sponge-like structure, where progesterone took a shape like flake.

• Resources Recycling
• /
• v.20 no.5
• /
• pp.46-51
• /
• 2011

An extraction study of neodymium (Nd) was investigated with different individual and mixer of extractants such as PC88A, D2EHPA, Cyanex 272, Versatic acid 10 and D2EHPA+Alamine-304-1, D2EHPA+Alamine-308, D2EHPA+TBP, D2EHPA+TOPO, PC88A+Alamine-336 and PC88A+TBP respectively. In all cases, it was observed that the extraction percentage of Nd increased with increasing equilibrium pH and extractant concentration but rather opposite observation was found that the extraction percentage of Nd decreased with increasing TBP concentration along with D2EHPA. Adding TBP to PC88A had no favorable effect on the extraction of Nd, whereas use of a mixture of PC88A with Alamine336, increased the extraction percentage of Nd under the same condition. Based on our experimental studies, this paper reports the results on the basic approach and extraction of neodymium.

• Analytical Science and Technology
• /
• v.7 no.3
• /
• pp.387-393
• /
• 1994

Quantitative analytical conditions for chromium using solvent extraction followed by atomic absorption spectrometry was studied. Trioctylamine(TOA) in tertiary amine or Trioctylmethylammoniumchloride(TOMAC) in quaternary ammonium salt, both containing octyl group was used as an anion exchangers. Absorbance were measured for the different kinds of acid added and as changing the concentration of acid by graphite furnace atomic absorption spectrometer. The maximum absorbance was obtained at the concentrations of HCl, 0.1M to 0.3M for TOA and 0.03M to 0.1M for TOMAC. Mole ratios over 1:1 of TOA or TOMAC dissolved in MIBK solution to chromium in sample shows optimum extraction efficiency while HCl was added to the MIBK. As a result of scrutinizing the extraction process, the methods employed in this experiment turned out to be better extraction efficiency for chromium, compared to similar extraction methods.