• Title/Summary/Keyword: anion-exchange

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A Study on the Variation of Anion Exchange Membrane of Hydrogen Generator of Alkaline Electrolysis (알칼리 수전해 수소제조의 이온 교환막 변화 분석)

  • Byun, Chang-Sub;Lim, Soo-Gon;Kim, Su-Kon;Shin, Hoon-Kyu
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.26 no.7
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    • pp.563-566
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    • 2013
  • We investigated the variation of anion exchange membrane of hydrogen generator of alkaline electrolysis. We detected the variation of elements and change of anion exchange membrane using EDS and FE-SEM. We detected two different sites of membrane because of different structure of membrane. $Sp_1$ shows that the distribution ratio of C, O, Al is 98% very higher than $Sp_2$ of 78%. Especially, the main elements of STS316 which is P, S, Fe, Ni were more detected at $Sp_2$ than $Sp_1$. We think that this result depends on the structure of membrane. This also affect the resistance, lifetime of membrane and decrease the efficiency of hydrogen production. We hope that this article is a foundation of developing of hydrogen production technology.

Basic Study for Development of Denitrogenation Process by Ion Exchange(IV) -A Kinetic Study in Continuous Column and an Economic Analysis- (이온교환법에 의한 탈질소 공정개발의 기초연구(IV) -연속식 반응기에서의 속도론과 경제성 분석-)

  • Lee, Min-Gyu;Ju, Chang-Sik;Chae, Yong-Gon;Kim, Sung-Il;Lee, Dong-Hwan;Yoon, Tae-Kyung
    • Journal of Environmental Science International
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    • v.9 no.3
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    • pp.261-266
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    • 2000
  • A kinetic study for nitrate removal by anion exchange resin was performed using continuous column reactors. Kinetic approach from the packed bed showed the reaction rate constant k$_1$ was 0.07~0.17 $\ell$/mgㆍhr and maximum exchange quantity q$_{o}$ was 27.75~31.81 mg/g. The results from the continuous column well agreed with that from the batch reactor. An economic analysis of the water treatment plant by anion exchange resin with a regenerating system was performed to design plant and process. Based on the treatment of 20 mg/$\ell$ nitrate-contained wastewater of 10,000 gallons per day to 2 mg/$\ell$, total capital cost and total annual cost are estimated to be 836 million wons and 211 million wons, respectively.y.

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Characteristics of Selectivity in Anion Exchanges (음이온 선택도 특성)

  • 이석중;안현경;이인형
    • 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.

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Removal of different anionic dyes from aqueous solution by anion exchange membrane

  • Khan, Muhammad Ali;Khan, Muhammad Imran;Zafar, Shagufta
    • Membrane and Water Treatment
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    • v.8 no.3
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    • pp.259-277
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    • 2017
  • Adsorption is a widely used technique for the removal of dyes from wastewaters by variety of adsorbents. In this work, the main focus is on the potential assessment of anion exchange membrane for the removal of different dyes using batch system and investigation of experimental data by applying various kinetic and thermodynamic models. The removal of anionic dyes i.e., Eosin-B, Eriochrome Black-T and Congo Red by anion exchange membrane BII from aqueous solution was carried out and effect of various parameters such as contact time, membrane dosage, temperature and ionic strength on the percentage removal of anionic dyes was studied. The experimental data was assessed by kinetic models namely pseudo-first-order, pseudo-second-order, Elovich liquid film diffusion, Bangham and the modified Freundlich models equation have been used to analyze the experimental data. These results indicate that the adsorption of these anionic dyes on BII follows pseudo-second-order kinetics with maximum values of regression coefficient (0.992-0.998) for all the systems. The adsorption of dyes was more suitable to be controlled by a liquid film diffusion mechanism. The adsorptive removal of dye Eosin-B and Eriochrome Black-T were decreased with temperature and thermodynamic parameters such as free energy (${\Delta}G^o$), enthalpy (${\Delta}H^o$) and entropy (${\Delta}S^o$) for adsorption of dyes on membrane BII were calculated at 298 K, 308 K and 318 K. The values of enthalpy and entropy were negative for EB and EBT representing that the adsorption of these dyes on BII is physiosorptive and exothermic in nature. Whereas the positive values of enthalpy and entropy for CR adsorption on BII, indicating that its adsorption is endothermic and spontaneous in nature. It is evident from this study that anion exchange membrane has shown good potential for the removal of dyes from aqueous solution and it can be used as adsorbent for dues removal on commercial levels.

Preparation and Characterization of Heterogeneous Anion Exchange Membrane for Recovery of Sulfate Ion from Waste Water (폐수 중 황산이온 회수를 위한 불균질 음이온교환막의 제조 및 특성)

  • Choi, Kuk-Jong;Choi, Jae-Hwan;Hwang, Eui-Hwan;Rhee, Young-Woo;Hwang, Taek-Sung
    • Polymer(Korea)
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    • v.31 no.3
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    • pp.247-254
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    • 2007
  • Heterogeneous anion exchange membranes were prepared by compression molding for the recovery of sulfate ion from waste water. The swelling ratio, transport number, and ion exchange capacity of the heterogeneous anion exchange membranes were increased and their electrical resistances were decreased as the amount of ion exchange resin content in the matrix was raised. The tensile strength of the heterogeneous anion exchange membrane was decreased with increasing the amount of ion exchange resin in the LLDPE. The tensile strength for the LDPE heterogeneous membrane containing 30 wt% anion exchange resin showed the highest value. The water content increased with increasing amount of ion exchange resin in the membrane. Moreover the highest transport number of the membrane was 0.86. The electrical resistance of LDPE matrix membrane with 50 wt% resin showed $46.5{\Omega}{\cdot}cm^2$. Current efficiency of electrodialysis for sulfate ion showed the highest value at the current density of $125 mA/cm^2$ in 0.5 mol/L sulfuric acids solution.

Removal of Orthophosphate Ions from Aqueous Solutions Using the Anion Exchange Resin in the Form of $Cl^-$ Ion ($Cl^-$ 형태의 음이온 교환 수지를 이용한 오쏘인산 이온의 제거에 관한 연구)

  • Kim, Ki-Chul;Park, Su-Jin;Cha, Ran;Jeong, Tae-Young;Chung, Hyung-Keun
    • 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.

A Study on Ion Exchange Characteristics with Composition and Concentration of Electrolyte, Ratio of Ion Exchange Resin (전해질 성분 및 농도, 이온교환 수지 비율에 따른 이온교환 특성 연구)

  • Ahn Hyun-Kyoung;Rhee In-Hyoung;Yoon Hyoung-Jun;Jeong Hyun-Jun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.7 no.4
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    • pp.727-732
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    • 2006
  • The object of this study was to investigate the influence of composition and concentration of electrolyte, ratio of cation to anion exchange resin of mixed ion exchange column in the performance of ion exchange. Also this work examined the removal capability of suspended solids by ion exchange resin and the effect of particule on the characteristics of ion exchange. Breakthrough time was extended as the amount of ions and particles present in liquid was decreased. The case of anion, the breakthrough sequence is $Cl^{-}, but the case of cation, the breakthrough sequence is $Na^{+}. As for the ratio of cation to anion exchange resin of 1:2, the breakthrough time was prolonged compared with that of 1:1 and 1:3. For the electrolyte of equal concentration containing suspended solid, breakthrough time was contracted less than 20%. It results in the increase in the removal capacity of cation exchange resin. For the higher ratio of cation exchange resin, suspended solids are shorten the cation's breakthrough time so that the runtime of ion exchange resin tower is increased.

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Study on Anion Exchange Membrane for the Alkaline Electrolysis (알칼리 수전해용 음이온교환막에 관한 연구)

  • Choi, Ho-Sang;Rhyu, Chul-Hwe;Lee, Sung-Un;Byun, Chang-Sub;Hwang, Gab-Jin
    • Transactions of the Korean hydrogen and new energy society
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    • v.22 no.2
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    • pp.184-190
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    • 2011
  • The membrane properties (membrane resistance and ion exchange capacity) of the five types of commercial anion exchange membrane, i.e. IOMAC, AHT, APS, AHA, AFN, were evaluated for the application in the alkaline electrolysis. The membrane resistance decreased in the order; in 1M KOH: AHT>IOMAC>AHA>AFN>APS; in 1M NaOH: AHT>IOMAC>AHA>APS>AFN. The ion exchange capacity decreased in the order: AFN>APS>AHT>AHA>IOMAC. The membrane life was determined from the change of membrane resistance in 1M KOH and NaOH with an increase of soaking time in 20 wt% KOH and 30 wt% NaOH solution. AHA membrane had a good membrane life in 20 wt% NaOH with its unchanged membrane resistance. And, AFN and AHA membrane had a good membrane life in 30 wt% NaOH with its unchanged membrane resistance.

Basic Study for Development of Denitrogenation Process by Ion Exchange(III) - A kinetic study in the batch reactor - (이온교환법에 의한 탈질소 공정개발의 기초연구(III) - 회분식 반응기에서의 반응속도론-)

  • 채용곤;이동환;김승일;윤태경;홍성수;이민규
    • Journal of Environmental Science International
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    • v.9 no.2
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    • pp.165-171
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    • 2000
  • A kinetic study for anion exchange was performed for commercially available Cl- type anion exchange resin in use to remove nitrate in water. The obtained results from the batch reactor were applied to the Langmuir and Freundlich models. The constants for Lagmuir model were qmax =29.82 and b=0.202, and for Freundlich model were K=5.509 and n=1.772. Langmuir model showed betterfit than Frendlich model for the experimental results. Ion exchange reaction rate was also calculated and the the approximate first-order reaction, rate constant k1 was 0.16 L/mg.hr. Effective diffusion coefficient was obtained in the range from $9.67$\times$10^{-8} cm^2/sec$ for initial concentration change, and from $6.09$\times$10^{-7} to 3.98$\times$10^{-6} cm^2/sec$ for reaction temperature change. Activation energy during the diffusion was calculated as 26 kcal/mol.

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