• Title, Summary, Keyword: Anion exchange

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Anion Exchange Membrane Having Permselectivity specific Anion in Electrodialysis

  • Sata, Toshikatsu
    • Proceedings of the Membrane Society of Korea Conference
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    • pp.1-6
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    • 1998
  • To change permselectivity between anions through the anion exchange membrane in electrodialysis, the various modified anion exchange membranes were prepared: highly crosslinked anion exchange membranes, anion exchange membranes having benzyl trialkylammonium groups with different carbon number of alkyl chain as anion exchange groups and anion exchange membranes having pyridinium groups with a hydrophilic or hydrophobic substituent at a different position as anion exchange groups. It became clear from the evaluation of these membranes that the degree of the hydrophilicity of the anion exchange membranes greatly affects the permselectivity between two artions. To increase the hydrophiticity of the anion exchange membranes further, electrodialysis was carried out in the presence of ethylene glycols and the permeation of strongly hydrated anions increased and that of less-hydrated anions decreased. It became clear that the change in the permselectivity between two artions is due to the change in the affinity of anions to the membranes, not the change in mobility ratio of the anions in the membranes phase.

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Preparation of an Anion Exchange Membrane Using the Blending Polymer of Poly(ether sulfone) (PES) and Poly(phenylene sulfide sulfone) (PPSS) (폴리에테르설폰-폴리페닐렌설파이드설폰 블렌딩 고분자를 이용한 음이온교환막의 제조)

  • Lee, Kyung-Han;Han, Joo-Young;Ryu, Cheol-Hwi;Hwang, Gab-Jin
    • Membrane Journal
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    • v.29 no.3
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    • pp.155-163
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    • 2019
  • The anion exchange membrane using the blending polymer of poly(ether sulfone) and poly(phenylene sulfide sulfone) was prepared. It was confirmed by EDXS and FT-IR analysis that the prepared anion exchange membrane had the -N- as an anion exchange group. The ionic conductivity in 1 mol/L $H_2SO_4$ aqueous solution was measured. The ionic conductivity of the prepared anion exchange membrane was 0.015~0.083 S/cm, and had a high value compared with AFN and APS as a commercial anion exchange membrane. Permeabilities of the vanadium ions through the prepared anion exchange membrane were tested to evaluate the possibility as a separator in vanadium redox flow battery. Vanadium ion permeation rate in the prepared anion exchange membrane had a low value compared with Nafion 117 as a commercial cation exchange and AFN as a commercial anion exchange membrane.

Influence of Quaternary Ammonium Anion Exchange Moieties onto Mechanical Properties of Radiation-grafting Anion Exchange Membranes (방사선그라프팅 음이온교환막의 기계적 물성에 대한 4차 암모늄 음이온교환기의 영향)

  • Ko, Beom-Seok;Sohn, Joon-Yong;Shin, Junhwa
    • Journal of Radiation Industry
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    • v.6 no.1
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    • pp.49-54
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    • 2012
  • Various anion exchange membranes were prepared by radiation graft copolymerization of vinylbenzyl chloride onto fluorinated films and subsequent quaternization with various tertiary amines such as trimethylamine, N,N-dimethylbuthylamine, N,N-dimethylaniline, and N-methylpiperidine. The quaternizations of the anion exchange membranes were confirmed by measuring of the ion exchange capacities of the membranes. The mechanical properties and the water uptakes were also measured. The elongation at break was found to be largely dependent on the fluorinated film, the quateranry ammonium, and the degree of grafting. The results indicate that the poly (ethylene-alt-tetrafluoroethylene) with quaternized trimethylamine moiety exhibits higher flexible property compared to the other prepared anion exchange membranes.

Adsorption of Selenium in Industrial Wastewater Using Anion Exchange Resin and Activated Carbon (음이온교환수지와 활성탄을 이용한 산업 폐수 중 셀레늄의 흡착)

  • Han, Sang-Uk;Park, Jin-Do;Lee, Hak-Sung
    • Journal of Environmental Science International
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    • v.18 no.12
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    • pp.1411-1416
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    • 2009
  • Several adsorbents were tried to remove the selenium ions from industrial wastewater and the following ascending order of the adsorption performance for the selenium at pH 9 was observed: cation exchange resin < chelate resin < zeolite < brown marine algae < granular activated carbon < anion exchange resin. Initial concentration of selenium(146 mg/L) in industrial wastewater was reduced to 63 mg/L of selenium at pH 9 by neutralization process. The maximum uptake of Se calculated from the Langmuir isotherm with anion exchange resin was 0.091 mmol/g at pH 10 and that with granular activated carbon was 0.083 mmol/g at pH 6. The affinity coefficients of Se ion towards anion exchange resin and granular activated carbon were 3.263 L/mmol at pH 10 and 0.873 L/mmol at pH 6, respectively. The sorption performance of anion exchange resin at the low concentration of Se, namely, was much better than that of granular activated carbon. The Se ions from industrial wastewater throughout neutralization process and two steps of adsorption using anion exchange resin was removed to 97.7%.

Study on the Preparation of Polyvinyl Chloride Anion Exchange Membrane as a Separator in the Alkaline Water Electrolysis (알칼리 수전해용 격막으로서 폴리염화비닐(polyvinyl chloride) 음이온교환막의 제조에 관한 연구)

  • Park, Jong-Ho;Bong, Soo-Yeon;Ryu, Cheol-Hwi;Hwang, Gab-Jin
    • Membrane Journal
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    • v.23 no.6
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    • pp.469-474
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    • 2013
  • An anion exchange membrane was prepared for a separator in the alkaline water electrolysis. An anion exchange membrane was prepared by the chloromethylation and amination of polyvinyl chloride (PVC) used as a base polymer. The membrane properties of the prepared anion exchange membrane such as the membrane resistance and ion exchange capacity were measured. The minimum membrane resistance of the prepared anion exchange membrane was $2.9{\Omega}{\cdot}cm^2$ in 1M NaOH aq. solution. This membrane had 2.17 meq./g-dry-membrane and 43.4% for the ion exchange capacity and water content, respectively. The membrane properties of the prepared anion exchange membrane was compared with that of the commercial anion exchange membrane. The membrane resistance decreased in the order; AHT>IOMAC> Homemade membrane> AHA>APS=AFN. The ion exchange capacity decreased in the order; Homemade membrane>AFN>APS>AHT>AHA>IOMAC.

The Effect of Ion Exchange Membrane on the Electrical Conduction in Metal Fuel Cell (금속연료전지에서 이온교환막이 전기전도에 미치는 영향)

  • Kim, Yong-Hyuk
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.59 no.12
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    • pp.2235-2239
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    • 2010
  • In this study, The cation exchange membrane and the anion exchange membrane affect in electrical conduction of metal fuel cell was investigated. Magnesium material as anode electrode and the NaCl solution dissolved with 5~15wt% as electrolyte were used for the metal fuel cell. It was found that magnesium slag where flows toward the air electrode was suppressed by using ion exchange membrane. The open circuit voltage variation during discharge has very flat pattern by using ion exchange membrane, but the case which is not the exchange membrane, the open circuit voltage increased according to time. When using the anion exchange membrane, the electric current was higher case of the cation exchange membrane, as a result of higher equivalent conductivity in anion Cl-. The cation exchange membrane was observed with the fact that the output power is excellent in compared with anion exchange membrane.

Problems and Solutions of Anion Exchange Membranes for Anion Exchange Membrane Fuel Cell (AEMFC) (음이온교환막연료전지용 음이온교환막의 문제점과 해결방안)

  • Son, Tae Yang;Kim, Tae Hyun;Kim, Hyoung Juhn;Nam, Sang Yong
    • Applied Chemistry for Engineering
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    • v.29 no.5
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    • pp.489-496
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    • 2018
  • Fuel cells are seen as eco-friendly energy resources that convert chemical energy into electrical energy. However, proton exchange membrane fuel cells (PEMFCs) have problems such as the use of expensive platinum catalysts for the reduction of conductivity under high temperature humidification conditions. Thus, an anion exchange membrane fuel cell (AEMFC) is attracting a great attention. Anion exchange fuel cells use non - Pt catalysts and have the advantage of better efficiency because of the lower activation energy of the oxygen reduction reaction. However, there are various problems to be solved including problems such as the electrode damage and reduction of ion conductivity by being exposed to the carbon dioxide. Therefore, this mini review proposes various solutions for different problems of anion exchange fuel cells through a wide range of research papers.

Anion Exchange Reaction Dynamics in Cesium Lead Halide Perovskite Quantum Dots (Cesium Lead Halide 페로브스카이트 양자점의 음이온 교환 반응 동역학)

  • Lee, See Maek;Jung, Hyunsung;Park, Woonik;Lim, Hyunseob;Bang, Jiwon
    • Journal of the Korean institute of surface engineering
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    • v.51 no.5
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    • pp.257-262
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    • 2018
  • Cesium lead halide perovskite quantum dots (QDs) have recently emerged as highly promising opto-electronic materials. Despite the relative facile anion exchange reactions in cesium lead halide perovskite QDs, in depth study of the anion exchange reactions such as reaction kinetics are required that can provide insight into the crystal transformation in the cesium lead halide perovskite QDs. Herein, we investigated the anion exchange reaction from $CsPbI_3$ QDs to $CsPbBr_3$ QDs with varying the particle size of the starting $CsPbI_3$ QDs. By characterizing the PL spectra in the anion exchange reaction process, we observed that discontinuous PL peak shifts during I-to-Br anion exchange reaction in starting $CsPbI_3$ QDs over a critical size. Origin of the discontinuous I-to-Br anion exchange kinetics are mainly due to thermodynamically unstable nature of the $CsPb(Br/I)_3$ alloy QDs.

Basic Study for Development of Denitrogenation Process by ion Exchange(II) (이온교환법에 의한 탈질소 공정개발의 기초연구(II))

  • 이민규;주창식
    • Journal of Environmental Science International
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    • v.7 no.1
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    • pp.89-95
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    • 1998
  • Ion exchange performance to remove nitrate in water was studied using commercially available strong base anion exchange resin of Cl- type in the batch and continuous column reactors. The performance was tested using the effluent concentration histories for continuous column or equilibrium conquilibrium between resin and solution. Anion exchange resin used in this study was more effective than activated carbon or zeolite for nitrate removal. With large resin amount or low initial concentration, nitrate removal characteristics for a typical gel-type resin was Increased. On considering the relation between the breakthrough capacity and nitrate concentration of the influent, the use of anion exchange resin were suitable for the hi선or order water treatment. The nitrate removal of above 90% could be possible until the effluent of above 650 BV was passed to the column. Thus, the commercially available strong base anion exchange resin of $Cl^-$ type used in thins study could be effectively used as economic material for treatment of the groundwater. The breakthrough curves showed the sequence of resin selectivity as $SO_4^{2-}$ > $NO_3$ > $NO^{2-}$ > $HCO_3^-$. The results of this study could be scaled up and used as a design tool for the water purification system of the real groundwater and surface water treatment processes.

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Crosslinking of Poly(2,6-dimethyl-1,4-phenylene oxide) Anion Exchange Membranes (폴리페닐렌 옥사이드 음이온 교환막의 가교결합)

  • Lee, Seung-Gwan;Kim, Mi-Yang;So, Won-Wook;Kang, Kyung-Seok;Kim, Kwang-Je
    • Membrane Journal
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    • v.28 no.5
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    • pp.326-331
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    • 2018
  • Crosslinking of poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) anion exchange membranes, which can be used for capacitive deionization (CDI), was investigated. PPO Anion exchange polymer was prepared through bromination and amination reaction steps and crosslinked with bisphenol A diglycidylether (BADGE), m-phenylenediamine (m-PDA), and hexamethylenediamine (HMDA). The gelation time by crosslinking was short in the order of HMDA > m-PDA > BADGE. The anion exchange membranes crosslinked at room temperature over a certain amount of crosslinking agent did not dissolve in an aprotic solvent such as 1-methylpyrrolidone (NMP) and the chemical durability of their membranes to organic solvent increased. The ion exchange capacity and water uptake of anion exchange membranes crosslinked with different crosslinker (BADGE) contents were measured and compared. The CDI performance of the crosslinked PPO anion exchange membrane immersed in the HMDA solution was almost the same as that of the non - crosslinked membrane except for the initial stage of the adsorption step.