• Journal of the Korean Chemical Society
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• v.36 no.5
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• pp.692-696
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• 1992

$NH_4^+ form cation exchange resin was used to separate one rare earth element from the rare earth mixture solution using Ln-EDTA eluent. Rare earth mixture solution was passed through the resin bed and eluted with 0.1M La-EDTA solution as an eluent. In here all the rare earth element except lanthanum ion are eluted and lanthanum ion absorbed in resin bed is eluted using 0.1M EDTA solution. If Ce-EDTA solution instead of La-EDTA solution was used as an eluent, all the rare earth element except cerium ion are eluted and cerium ion is eluted with 0.1M EDTA solution. This method can be applied to separate the individual rare earth element from the mixture. The separation mechanism is as follows: Absorption : 3RNH_4 ＋ Ln^{3+} = R_3Ln ＋ 3NH_4^+, La-EDTA elution : R_3Ln ＋ La-Y- = R_3La ＋ Ln-Y-, EDTA elution : R_3La ＋ HY^3- = La_-Y ＋ RH ＋ 2R^-.$

• Korean Journal of Food Science and Technology
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• v.22 no.6
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• pp.711-715
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• 1990

Continuous column chromatographic separation of lysozyme from egg white was investigated. A weak acid type cation exchange resin, Duolite C-464, was used because of high lysozyme recovery and ease of column operation in this experiment. The resin was equilibrated at $pH\;7.9{\pm}0.1$ in Na+form. Continuous lysozyme separation was processed by repeating cycles(one cycle : resin equilibration, flow egg white, rinse, lysozyme elution) in automated preparative Liquid Chromatography(LC) system(column size ; i.d. 50 mm, resin bed volumn ; 1020 ml). At comparison of UV levels in rinse end point and elution end point of every cycle, the UV levels of rinse end point are maintained below 30% for 19 cycles and that of elution end point are also maintained below 30% for 17 cycles, stably, but was increased above 50% after 18 cycle. That indicated the eluting ability of lysozyme was reduced conspicuously after 18 cycle in continuous cycling process. The recovery of lysozyme was maintained above 90% from one to 17 cycle, but was decreased to 72% and 65% in 18 cycle and 19 cycle, respectively.

• Korean Journal of Environmental Agriculture
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• v.24 no.3
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• pp.253-260
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• 2005

Salt accumulation in the plastic film house soils under continuous cultivation condition causes problems such as salt damages to plants, nitrate accumulation in vegetables, groundwater contamination, etc. due to excess application of fertilizers. Objective of this research was to find an optimum adsorbent to reduce salt concentration in the soil solution of plastic film house soils, where crop injuries have been observed due to the salt accumulation. The soils were significantly high in available P $(1,431{\sim}6,516mg\;kg^{-1}),\;NO_3-N\;(117.60{\sim}395.73mg\;kg^{-1})$, exchangeable Ca $(4.06{\sim}11.07\;cmol_c\;kg^{-1})$ and Mg $(2.59{\sim}18.76\;cmol_c\;kg^{-1})$, as compared to those of the average upland soils in Korea. Soils were treated with each of adsorbent such as ion-exchange resin, zeolite, rice bran, etc. at 2% level and prepared into saturated-paste samples. After equilibrium, soil solution was vacuum-extracted from the soil and measured for changes of the pH, EC, and concentrations of $Ca^{2+},\;Mg^{2+},\;K^+,\;Na^+,\;{NH_4}^+,\;{PO_4}^{3-}\;and\;{NO_3}^-$. Rice bran effectively removed ${PO_4}^{3-}\;and\;{NO_3}^-$ in the soil solution up to 100%. Efficiency was decreased in the orders of rice bran > ion-exchange resin > zeolite. Removal efficiencies of zeolite and ion-exchange resin for $Ca^{2+}$ were ranged from 1 to 65% and from 7 to 61%, respectively. Ion-exchange resin was also effective for removing $Mg^{2+},\;K^+,\;Na^+,\;and\;{NH_4}^+$. Overall results demonstrated that rice bran and ion-exchange resin could be applicable for salt accumulated soil to remove the respective anion and cation.

• Applied Chemistry for Engineering
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• v.9 no.2
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• pp.249-254
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• 1998

To synthesize cation exchange resin which has thermal stability, the sulfonated poly(ether ether sulfone) (SPEES) was obtained by sulfonation after synthesis of poly(ether ether sulfone) (PEES). It was prepared from hydroquinone and dichlorophenyl sulfone. From FT-IR results, the sulfonation was confirmed by the bands of asymmetric O=S=O stretching of $SO_3Na$ Na group at $1140cm^{-1}$ and S-C stretching at $621cm^{-1}$. The optimum condition of the sulfonation of PEES, based on IR absorbance, was 3 hr of reaction time, $30^{\circ}C$ of reaction temperature, and chlorosulfonic acid of 150 mol%. Ion exchange capacities calculated by the IR absorbance of PEES sulfonated in optimum condition was 6.2 meq/g, which was nearly similar to the ion exchange capacity calculated by titration. When the metal ion was adsorved, small brain, lump, hulled millet shape and compact surface, were observed in the morphology of SPEES.

• Journal of the Korean Chemical Society
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• v.30 no.5
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• pp.449-455
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• 1986

Various polymer metal complexes have been synthesized from anhydrous $AlCl_3,\;FeCl_3,\;SbCl_5,\;SnCl_4\;and\;ZnCl_2$ with cation exchange resin in carbon disulfide solvent. The forms of the surfaces and sectioned beads of these polymer metal complexes have been observed using scanning electron probe microanalyzer. To examine the catalytic activity of polymer metal complexes, the esterification of various dibasic acids with alcohols have been carried out. Polymer metal complexes were found to be the effective catalyst for esterification of dibasic carboxylic acids.

• Journal of the Korean Society of Food Science and Nutrition
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• v.3 no.1
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• pp.69-76
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• 1974

The method of amino acid sequence determination from the C-terminal amino acid is proposed and mass spectrometric identification of thiohydantoins described previously. In this paper was discussed the fragmentation of thiohydantoin-ring by deutero substitution and model tripeptide have been degraded through three stages each, with interpretable results. The conditions employed in this method are mild enough for biological materials. The main features of the method are the following. 1. Thiohydantoins were formed in a non-aqueous medium a mixture of acetic anhydride, acetic acid and ammonium thiocyanate. 2. Mass sepectra of thiohydantoins derived from 20 amino acids were obtained with a mass spectrometer, JEOL model JMS-06H. 3. Cleavage of peptidyl thiohydantoin was made with an acidic from of a cation-exchange resin. (Amberlite IR-120) 4. Separation of the cleaved thiohydantoin and the parent peptide less one amino acid moiety was made by chromatography on a Sephadex G-10 column. 5. The peptide fraction was concentrated by freezedrying. 6. Thiohydantoin derivative of carboxyl terminal amino acid residue was introduced with a direct inlet probe in methanol solution.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.6 no.1
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• pp.138-143
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• 1996

After oral administration of 14C-labelled $N^G$-mono[methyl-14C]-L-arginine into rats, 38.2 % and 14.7 % of the administered radioactivity bad been recovered in the urine and stool during 10 days. In the urine, 59.4 % of the radioactivity was recovered in the first 24-hours and used for the indentification of the formation of methylamine. The strong cation-exchange resin column chromatography showed 6.3 %, 7.4 %, 4.9 %, and 81.5 % of the distributions of radioactivity of the neutral, monomethylamine, basic, and uneluted portions, respectively. The radioactivity of monomethylamine portion reeluted into the column chromatography was 39.5 %. The radioactivities corresponding monomethylamine in the column chromatography, thin-layer chromatography, and thin-layer electrophoresis were 39.5 %, 37.3 %, and 28.8 % of the recovered radioactivity, respectively.

• Bulletin of the Korean Chemical Society
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• v.29 no.1
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• pp.57-60
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• 2008

Catalytic oligomerization of isobutene to produce triisobutenes has been performed over a cation-exchange resin (Amberlyst-35) by using commercial C4 feeds. The catalytic activity in the oligomerization was retained without deactivation up to 90 h of reaction in a simulated reaction feed without butadiene, but its activity was significantly affected by the presence of butadiene in commercial C4 feeds. The isobutene conversion with time-on-stream was significantly decreased in the presence of butadiene, indicating the catalyst deactivation by butadiene. However, the stable activity for trimerization was accomplished when the oligomerization was carried out after eliminating butadiene by hydrogenation of the feeds. This work demonstrates that butadiene plays a role as a catalyst poison on the solid acid catalyst, so that its removal in the reactant feed is essential for practical application of trimerization.

• Journal of the Korean Chemical Society
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• v.22 no.1
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• pp.25-29
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• 1978

Cobalt(III) complex containing ethylenediamine-triacetate and trimethylenediamine has been isolated from the reaction of ethylenediamine-tetraacetatocobaltate(III) with trimethylene-diamine in aqueous solution by Dowex 50W-X8, cation exchange resin in $H^+$ form. The ethylenediamine-triacetate($EDTRA^{3-}$) ligand coordinates to the cobalt(III) ion as a quadridentate with a free acetate branch. It has been observed that the complex has trans(O-O) (1) structure via the elemental analysis, UV, IR and NMR data.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.4
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• pp.555-560
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• 2000

Anthocyanin pigments of purple-fleshed sweet potato (Ipomoea batatas) were extracted with methanol containing 1% HCL and purified with Amberlite IRC-50 cation exchange resin column chromatography. ndividual pigments were isolated by paper chromatography. Among the four bands obtained by paper chromatography, three major bands were identified to be pure pigments by HPLC system. Two pigments were identified through the analysis of acyl moiety, sugar moiety, alkaline degradation products of aglycone, Rf value of paper chromatogram and retention time of HPLC. The anthocyanin pigments of purple-fleshed weet potato seemed to be composed of peonidin-3-diglucoside-5-glucoside acylated with caffeic or ferulic acids.