• Journal of Korean Society of Environmental Engineers
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• v.34 no.3
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• pp.162-167
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• 2012

The removal of orthophosphate ions from aqueous solutions by the anion exchange resin in the form of $Cl^-$ ion was investigated to elucidate the ion exchange mechanism which depends on the forms of orhthophoshate ions. In addition, the effects of alkalinity and other common anions were studied. The results showed that the orhthophosphate ions with the oxidation state of 2 and 3 ($HPO{_4}^{2-}$ and $PO{_4}^{3-}$) were effectively removed by the anion exchange resin, whereas the part of the $H_2PO_4{^-}$ ion passed through the ion exchange column. This suggested that the affinity of $H_2PO_4{^-}$ to the ion exchange resin was comparable with that of $Cl^-$ ion. In all cases, the effluent pHs have shown to be much lower than the calculated values, indicating that more $Cl^-$ ions than the orthophosphate equivalents in the influent were eluded. As the alkalinity increases, the decrease in pH was minimized. When the alkalinity was 100 mg/L ($CaCO_3$) or greater, 100 mg/L orthophosphate ions including $H_2PO_4{^-}$ were completely removed. The common anions such as $SO{_4}^{2-}$ and $NO_3{^-}$ were also removed by the anion exchange resin, and thus decreased the ion exchange capacity for the removal of orthophosphate.

• Proceedings of the Optical Society of Korea Conference
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• 2000.02a
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• pp.262-263
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• 2000

이온교환방법은 착색된 유리를 생산하기 위하여 수세기 전부터 연구되어 왔다. 1972년 Izawa와 Nagome가 silicate 유리에 Tl$^{+}$이온을 치환하여 평판 도파로를 만든 후, 이온교환은 도파로나 마이크로 렌즈제작 등에 활발하게 연구되어 왔다. 유리 도파로는 광의 진행손실이 적으며, 광섬유와의 우수한 호환성, 그리고, 제작이 용이하고 가격이 싼 장점 등으로 인하여 많은 연구가 진행되고 있는 재료이다. 그러나, 유리에 이온교환으로 광소자를 만들기 위해서는 굴절률변화를 정확하게 예측해야한다. 따라서, 유리에서 이온들의 확산특성을 정확하게 분석하고 실험적으로 확립하는 연구는 매우 중요하다고 하겠다. (중략)

• Journal of the Korea Academia-Industrial cooperation Society
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• v.5 no.2
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• pp.98-102
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• 2004

Ion exchange behavior and property change of soda-lime-silicate glass by advanced ion exchange process were investigated. Refractive index, specific gravity and optical transmittance were changed similarly to $K^+$ ion penetration depth, and amount of ion exchange increased with the increase of the time and temperature. Especially, thermal expansion decreased greatly because of the structural compaction and residual stress by ion exchange process.

• Journal of the Korean Chemical Society
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• v.39 no.5
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• pp.371-378
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• 1995

The triazacrown compound, 1,7-dioxa-4,10,13-triazacyclopentadecane trihydrobromide salt (Na3O2-3HBr) was synthesized. And this compound was used to synthesize the new ion exchanger, which combined with Merrifield peptide resin. This new ion exchanger had a capacity of 3.2 meq/g dry resin. And the distribution coefficients of alkali and alkaline earth metal ions on this ion exchanger in the various concentrations of hydrochloric acid were determined. The ion exchange behaviors of alkali and alkaline earth metal ions in the various hydrochloric acid concentrations are, also, discussed.

• Polymer(Korea)
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• v.24 no.6
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• pp.763-769
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• 2000

The multifunctional cation exchangers, sulfonated polypropylene-g-(acrylic acid/styrene) [PP-g-(AAc/Sty)] were synthesized by the irradiational grafting of AAc and Sty onto PP staple fabric with electron beam accelerator and its subsequent sulfonation. The highest degree of grafting obtained was 190% at a monomer mixture of 30 vol% AAc: 70 vol% Sty and a solvent mixture of 30 vol% water : 70 vol% methanol and the degree of grafting decreased with an increase of the AAc content in the monomer mixture at constant solvent content. Maximum ion exchange capacity of the copolymer was 4.6 meq/g. The Li$^{+}$ adsorption ability of the copolymer synthesized in the study was the best among PP-g- AAc, sulfonated PP-g-Sty, and sulfonated PP-g-(AAc/Sty).).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.3 no.3
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• pp.194-197
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• 2002

Ion exchange is a chemical reaction between the ions in solution phase and ions in solid phase and is widely used in softening, demineralization, removal and collection of specific ions, and ion migration in the ground water. The ion selectivity depends on the charge and the hydrated radius of ion. The objective of this study was to examine the applicability of anion selectivity obtained from the ion exchange equilibrium OH/sup -/ < F/sup -/ < HCO/sup -/ < Cl/sup -/ < Br/sup -/ ≤ NO₃/sup -/ < SO₄/sup 2-/ to the column ion exchange. The column ion exchange was facilitated in the lower charge of counter-ion in the background electrolyte.

• Proceedings of the KAIS Fall Conference
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• 2002.05a
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• pp.140-143
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• 2002

연속 이온교환 평형 모델을 개발하여 원자력발전소 탈염기의 성능을 평가한 결과 특정이온의 누출 현상과 유입수 및 유출수중 이온농도 비율이 운전조건에 따라서 달라짐을 확인하였다. 본 모델은 국부 불완전 평형을 고려할 수 없으나 다성분 존재하의 경쟁적 이온교환을 묘사할 수 있는 장점을 가지고 있다.

• Membrane Journal
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• v.33 no.3
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• pp.137-147
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• 2023

In this study, Br-PPO was developed by applying additive organic particles through a suspension polymerization synthesis method. The anion exchange membrane fuel cell system performance was evaluated using it to an anion exchange membrane. To improve the performance, organic ion exchange particles were prepared and added to the anion exchange membrane. Chemical structure analysis and synthesis were determined through FT-IR and NMR, and tensile strength and thermal stability were measured through TGA and UTM to determine whether it could be driven. Before the anion exchange membrane fuel cell test, the performance was evaluated by measuring the ion conductivity and ion exchange capacity. Finally, the Br-PPO-TMA-SDV (0.7%) anion exchange membrane with excellent ion conductivity and ion exchange capacity was introduced into the fuel cell system. Its performance was compared with FAA-3-50, a commercial membrane, to determine whether it could be introduced into a fuel cell system.

• Proceedings of the KAIS Fall Conference
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• 2006.05a
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• pp.596-598
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• 2006

본 논문에서는 수지 조성비 및 수지탑 배열이 이온교환 특성에 미치는 영향을 조사하기 위하여 전해질 농도는 $Na^+\;125ppm$, $Cl^-\;315ppm$ 유속은 500ml/min, 이온교환 수지는 ROHM&HAAS IR 120 양이온 수지와 ROHM&HAAS IRA 402 음이온 수지를 사용하였고, 수지탑 배열은 혼상-혼상-음이온, 혼상-음이온-혼상, 음이온-혼상-혼상 수지탑 순으로, 이온교환 수지탑의 양 음이온교환 수지의 조성 비율은 1:1, 1:2, 1:3 로 변화하여 실험한 결과 이온교환 수지의 조성비 변화에서는 양 음이온교환 수지 조성비 1:2의 경우 1:1, 1:3의 경우보다 파과시간이 연장되었다. 수지탑 배열이 음이온-혼상-혼상 수지탑인 경우 혼상-혼상-음이온 수지탑 배열과 파과시간을 비교해보면 약 60% 파과시간이 연장되었다. 따라서 수지탑 배열은 음이온-혼상-혼상 수지탑 순으로, 수지 조성비는 1:2일 때 가장 효율적인 것으로 나타났다.

• Applied Chemistry for Engineering
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• v.5 no.3
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• pp.406-412
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• 1994

The ion-exchange properties of $Ca^{2+}$ and $Mg^{2+}$ ions have been studied in ${\delta}-Na_2Si_2O_5$ synthesized from water glass. Results show that optimum temperature for synthesis of ${\delta}-Na_2Si_2O_5$ was $725^{\circ}C$. Ion-exchange isotherms for $Ca^{2+}$ and $Mg^{2+}$ exchange for $Na^+$ in the synthetic ${\delta}-Na_2Si_2O_5$ show that the ion-exchange capacity of magnesium is better than that of calcium, and the ion-exchange of magnesium is less sensitive for temperature than that of calcium. When initial pH of solution is increased between 2 and 6, the ion-exchange capacities of magnesium and calcium decrease a little. However, they are almost constant above pH 6 because of alkali buffer effect of ${\delta}-Na_2Si_2O_5$. In the thermodynamic studies, it was found that Gibbs free energies of reaction of calcium ion-exchange are larger than those of magnesium ion-exchange with inverse order of selectivity. The standard enthalpy and entropy of reaction of calcium ion-exchange are larger than those of magnesium ion-exchange.