• Proceedings of the Membrane Society of Korea Conference
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• 2004.11a
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• pp.103-106
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• 2004

• Membrane Journal
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• v.12 no.4
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• pp.247-254
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• 2002

In order to develop the ion exchange membranes which would be used in direct methanol fuel cell (DMFC), the polysulfone polymer was sulfonated using chlorosulfonic acid (CSA) and trimethylchlorosilane(TMCS). It has been characterized in terms of ion conductivities, methanol crossover, swelling degree and ion exchange capacities for the heat untreated and treated membranes at $150^{\circ}C.$ Typically, the methanol permeability and ion conductivity at the mole ratio of 1.4 between polysulfone repeating unit and sulfonating agents showed $2.87{\times}10^{-7}\; cm^2/s$(without heat treatment), $1.52{\times}10^{-7}\; cm^2/s$(with heat treatment) and $1.10{\times}10^{-2}\; S/cm$(without heat treatment), $0.87{\times}10^{-2}\;$ S/cm(with heat treatment), respectively. After the mole ration of 1.4 both values indicated mild increase.

• Applied Chemistry for Engineering
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• v.21 no.1
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• pp.52-57
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• 2010

Although chemical sedimentation and ion exchange are usually applied to the treatment of heavy metal ions and radioactive cations, they have some serious disadvantages like a great consumption of chemicals, the disposal of valuable metals, and the secondary pollution of soil by the solid-waste. The advanced countries recently have studied the electrochemical ion exchange, combined electrochemical reduction and ion exchange, for the development of the alternative technique. This study has been performed to investigate the optimum condition for the preparation of the nickel hexacyanoferrate (NiHCNFe) which is an electrochemical ion exchanger. NiHCNFe film was deposited on the surface of nickel plate by chemical method or electrochemical method. The morphology and composition of NiHCNFe were observed by SEM and EDS, respectively. The peak current density of NiHCNFe was measured from the cyclic voltammograms of the continuous oxidation-reduction reaction in a parallel plane ion exchange electrode reactor. It was found that the chemical preparation method was better than the electrochemical method. The concentrated NiHCNFe was apparently deposited on nickel plate when dipping in the preparing solution for 118 h, especially. It also had a best durable performance as an ion exchange electrode.

• Membrane Journal
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• v.30 no.4
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• pp.276-281
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• 2020

A research was conducted on the removal of ion from the solution involving the alkali metal ion and chlorine ion using ion exchange resin. The cation exchange resin and anion exchange resin was used for the remove of metal ion (Na⁺ and K⁺) and chlorine ion (Cl^-), respectively. In the case of solution A (involving 36,633 ppm of Na⁺ and 57,921 ppm of Cl^-), the Na⁺ ion and Cl^- ion were removed over 99% within 20 min. In the case of solution B (involving 1,638 ppm of K⁺), the K⁺ ion was removed over 99% within 3 min.

• Membrane Journal
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• v.13 no.1
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• pp.47-53
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• 2003

Poly(ether ether ketone)(PEEK) was sulfonated using sulfuric acid and blended with polysulfone with various ratios. The blended polymer electrolyte membranes were characterized in terms of methanol permeability, proton conductivity and ion exchange capacity. As the amount of sulfonated PEEK increased, both methanol permeability and proton conductivity increased. This was due to the increase of ion exchange capacity. The experimental results indicated that the blend membrane with 20% polysulfone was the best choice In terms of the ratio of proton conductivity to methanol permeability.

• Proceedings of the Membrane Society of Korea Conference
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• 1996.10a
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• pp.80-81
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• 1996

일반적으로 고분자전해질은 고유의 독특한 특성으로 고분자 분리막, 이온교환수지, 의료용고분자등에 널리 응용이 되고 있다. 이러한 고분자전해질은 음이온성과 양이온성이 있으며, 그 이온적성질으로 인하여 반대의 전하를 띄는 고분자전해질들끼리 결합하는 성질을 가지고 있다. 이러한 고분자전해질 착체는 고분자전해질과는 또 다른 고유한 특성을 나타내고 있으며, 특히 고분자분리막과 의료용재료 분야에 응용가능성이 큰 물질이다. 특히 양이온성과 음이온성을 동시에 보유하고 있는 구조적 특성에 의하여 산성과 염기성 모두에서 감응성을 나타낼 수 있다. 일반적으로 고분자 겔의 경우 산성 또는 염기성 영역에서 해리되는 특성에 의하여 pH 감응성을 나타내지만 한쪽 영역에서만 특성을 나타내고 있다. 본 실험에서는 키토산과 폴리아크릴산으로 제조된 고분자전해질착체를 이용하여 pH변화에 따른 함수거동을 관찰함으로써 양쪽의 pH 감응성을 고찰해보고자 하였다.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.3 no.4
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• pp.269-278
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• 2005

In order to produce only a pH-controlled solution without discharging any unwanted solution, this work has developed a continuous electrolytic system with a pH-adjustment reservoir being placed before an ion exchange membrane-equipped electrolyzer, where as a target solution was fed into the pH-adjustment reservoir, some portion of the solution in the pH-adjustment reservoir was circulated through the cathodic or anodic chamber of the electrolyzer depending on the type of the ion exchange membrane used, and some other portion of the solution in the pH-adjustment reservoir was discharged from the electrolytic system through the other counter chamber with its pH being controlled. The internal circulation of the pH-adjustment reservoir solution through the anodic chamber in the case of using a cation exchange membrane and that through the cathodic chamber in the case of using an anion exchange membrane could make the solution discharged from the other counter chamber effectively acidic and basic, respectively. The phenomena of the pH being controlled in the system could be explained by the electro-migration of the ion species in the solution through the ion exchange membrane under a cell potential difference between anode and cathode and its consequently-occurring non-charge equilibriums and electrolytic water- split reactions in the anodic and cathodic chambers.

• Membrane Journal
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• v.26 no.1
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• pp.43-54
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• 2016

In this study, we have prepared engineering polymer-based ionomers and pore-filled ion-exchange membranes (PFIEMs) employing a porous polyethylene substrate and combined them to fabricate the ionomer-PFIEM composite membranes for the reverse electrodialysis (RED) application. Both the electrochemical properties comparable to those of the commercial ion-exchange membranes (AMX/CMX, Astom Corp., Japan) and the physical stability adaptable to the practical uses have been achieved by integrating the ionomers having a high ion conductivity and the PFIEMs with an excellent mechanical strength. The RED performances have been evaluated by employing the prepared ionomer-PFIEM composite membranes and therefore excellent power generation performances were shown as the levels of 86.4% and 104.8% for the anion-exchange membrane and cation-exchange membrane, respectively, compared with those of the commercial membranes.

• Applied Chemistry for Engineering
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• v.16 no.1
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• pp.144-149
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• 2005

Sulfonated poly(ether ether ketone) (SPEEK) was blended with poly(ether sulfone) (PES) at various compositions. To investigate the possibility of using the blend membranes as polymer electrolyte membranes for direct methanol fuel cell, the blend membranes were characterized in terms of methanol permeability, proton conductivity, ion exchange capacity, and water content. Both proton conductivity and methanol permeability of SPEEK were relatively high. As the amount of PES increased, methanol permeability decreased more rapidly compared to proton conductivity. The experimental results indicated that the blend membrane with 40 wt% PES was the best choice in terms of the ratio of proton conductivity to methanol permeability.

• Membrane Journal
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• v.34 no.1
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• pp.10-19
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• 2024

The bipolar membrane is an ion exchange membrane consisting of a cation exchange layer, an anion exchange layer, and an interface layer, and is a membrane that generates protons and hydroxide ions based on water dissociation characteristics. Using these properties, research is being conducted in various application fields such as the chemical industry, food processing, environmental protection, and energy conversion and storage. This paper investigated the concept of bipolar membrane, water dissociation mechanism, and water dissociation catalyst to provide a comprehensive understanding of bipolar membrane technology, were investigated. Lastly, we also investigated the bipolar membrane process that has been recently applied to energy technology.