• Journal of Environmental Health Sciences
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• v.19 no.2
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• pp.40-45
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• 1993

A solvent extraction system of copper-thiocyanate complex into various types of alkylamines such as secondary, tertiary and quaternary ammonium salt for the determination of trace copper by atomic absorption spectrometry is presented. The maximum extraction of copper shows at 0.1 M-thiocyanate and single extraction with 10 ml of 1% amine-MIBK from 50 ml of aqueous solution is enough to be quantitative for micro amounts of copper. The effect of amine diluents and of diverse ions are also examined.

• Bulletin of the Korean Chemical Society
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• v.32 no.9
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• pp.3429-3432
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• 2011

Distribution diagram of $FeCl_2$ in HCl solution indicated that $FeCl^+$ was a predominant species in strong HCl solution up to 10 M. Solvent extraction of $FeCl_2$ has been performed in the HCl concentration range from 5 to 9 M by using Alamine336 as an extractant. Interaction parameter of $FeCl^+$ for Bromley equation was estimated from our solvent extraction data. This parameter thus obtained in our study can be employed in calculating the activity coefficient of $FeCl^+$ in high concentration of HCl.

• Resources Recycling
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• v.27 no.3
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• pp.93-99
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• 2018

Effective extraction of platinum group elements by dissolving waste platinum scrap from the display industry and solvent extraction, was studied. The extracted platinum solution was prepared as a precursor solution for diesel automotive exhaust gas purification catalyst and its catalytic activity was tested. The behavior of aqueous species of platinum was investigated through solution chemistry and based on the existence and behavior of these chemical species, the possibility of extraction and separation was established. By dissolving waste scrap by electrochemical method, the dissolution time of scrap was shortened and the extraction efficiency was increased. Through separation and removal of rhodium component, solvent extraction by TBP, and stripping by hydrochloric acid, Pt-Chloride-$H_2O$ solution was prepared. And then, an platinum amine complex solution through amination reaction with this solution as a raw material was prepared. The possibility of producing high-value platinum compounds from platinum group waste scrap was investigated by preparing platinum amine complex solution and then examining the catalytic activity with this amine precursor on the combustion reaction of carbon black.

• Bulletin of the Korean Chemical Society
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• v.32 no.4
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• pp.1228-1230
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• 2011

A new amine receptor 2 utilizing anthracene and nitrophenyl group as signaling group was designed and synthesized. The receptor 2 only utilizes four amine N-H's and 9-anthracenyl hydrogen to bind anions. The receptor 2 can bind anions through hydrogen bonds with a selectivity of $CH_3CO_2^-$ > $H_2PO_4^-$ > $F^-$ > $C_6H_5CO_2^-$ > $Cl^-$ in highly polar solvent such as DMSO without protonation of amine.

• Bulletin of the Korean Chemical Society
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• v.31 no.5
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• pp.1155-1158
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• 2010

Microwave-assisted Michael reaction between EMME and various amines such as diphenylamine, 4-methyl-N-phenylbenzenamine, N-phenylnaphthalen-1-amine, dihexylamine, diisopropylamine, and 4-nitrobenzenamine were described. Solvent-free conditions on alumina as solid support in the presence of $K_2CO_3$ catalysts gave moderate to good yields (55 - 93%) of diethylmalonate analogues having enamine moieties under focused microwave irradiation.

• KEPCO Journal on Electric Power and Energy
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• v.2 no.1
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• pp.103-108
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• 2016

Carbon Capture and Storage technologies are recognized as key solution to meet greenhouse gas emission standards to avoid climate change. Although MEA (monoethanolamine) is an effective amine solvent in $CO_2$ capture process, the application is limited by high energy consumption, i.e., reduction of 10% of efficiency of coal-fired power plants. Therefore the development of new solvent and improvement of $CO_2$ capture process are positively necessary. In this study, improvement of $CO_2$ capture process was investigated and applied to Test Bed for reducing energy consumption. Previously reported technologies were examined and prospective methods were determined by simulation. Among the prospective methods, four applicable methods were selected for applying to 0.1 MW Test Bed, such as change of packing material in absorption column, installing the Intercooling System to absorption column, installing Rich Amine Heater and remodeling of Amines Heat Exchanger. After the improvement construction of 0.1 MW Test Bed, the effects of each suggested method were evaluated by experimental results.

• YAKHAK HOEJI
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• v.18 no.3
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• pp.183-189
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• 1974

Distribution coefficients between nitrobanzene solution and deionized water, show a straight line when the number of alkyl radicals against the logarithm of distribution coefficient of the salts was plotted. After extracting salts of the indicator and the cationic surfactants with organic solvents, and employing the colorimetric method was used. A calculation method of distribution coefficients of the salts in the organic solvent has been suggested and it could be used for the extraction equilibrium of the primary amine, $CH_{3}(CH_2)_{n}NH_3^+$ secondary amine, $CH_{3}(CH_2)_{n}NH_{2}(CH_3)^+$, tertiary amine $CH_{3}(CH_2)_{n}NH(CH_3)_2^+$ and quaternary ammonium, $CH_{3}(CH_2)_{n}N(CH_3)_3^+$MO$^-$salts, (n=3,5,7,11).

• Journal of the Korean Applied Science and Technology
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• v.27 no.3
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• pp.273-281
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• 2010

Nickel recovery method was studied by the wet process from the catalyst used in hydrogenation process. Nickel content in waste catalyst was about 16%. At the waste catalyst leaching system by the alkaline solution, selective leaching of nickel was possible by amine complex formation reaction from ammonia water and ammonium chloride mixed leachate. The best leaching condition of nickel from mixed leachate was acquired at the condition of pH 8. LIX65N as chelating solvent extractant was used to recover nickel from alkaline leachate. The purity of recovered nickel was higher than 99.5%, and the whole quantity of nickel was recovered from amine complex.

• Resources Recycling
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• v.26 no.2
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• pp.3-10
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• 2017

Rare earth elements with high purity are demanded for the manufacture of advanced materials. Light rare earth elements are contained in domestic monazite and Ni-MH batteries. In this paper, solvent extraction to separate the light rare earth elements from hydrochloric acid leaching solutions of these resources was discussed. A mixture of cationic and tertiary amine shows synergistic effect on the extraction of LREEs and the extent of pH decrease during extraction is reduced. The effect of solution pH on the extraction and synergism was reviewed. Acquisition of the operation data with mixer-settler on the separation of LREEs by this mixture is necessary to develop a process.

• Bulletin of the Korean Chemical Society
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• v.17 no.3
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• pp.234-238
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• 1996

Second-order rate constants have been measured spectrophotometrically for the reaction of p-nitrophenyl acetate (PNPA) with morpholine, piperazine and piperidine in MeCN-H2O mixtures of varying compositions. The rate of the present aminolysis decreases upon additions of MeCN into H2O up to near 30-40 mole % MeCN and remains nearly constant upon further additions of MeCN. The reaction of PNPA with anionic nucleophiles, such as HO-, p-chlorophenoxide and butane-2,3-dione monoximate, has also exhibited two distinguishable reactivity zones. However, the reactivity trend for the anionic nucleophiles is quite different from the one obtained for the amine system, e.g. an initial rate decrease in the H2O-rich region followed by an increasing rate trend upon further additions of MeCN in the MeCN-rich region. The rate behaviors shown by the amine system in the MeCN-rich and by the anionic system in the H2O-rich region are unexpected based on the Hughes-Ingold rules. The present unusual rate trends have been attributed to changes in the solvent structure and pKa of the nucleophiles upon the addition of MeCN into H2O. The effect of solvent appears to be more significant for the TS than the GS, and the TS structure is considered to become tighter in the higher MeCN concentration.