• Title/Summary/Keyword: 이온교환막

Search Result 194, Processing Time 0.02 seconds

Preparation and Electrochemical Applications of Pore-filled Ion-exchange Membranes with Well-adjusted Cross-linking Degrees: Part II. Reverse Electrodialysis (가교도가 조절된 세공충진 이온교환막의 제조 및 전기화학적 응용: Part II. 역 전기투석)

  • Song, Hyun-Bee;Moon, Ha-Neul;Kim, Do-Hyeong;Kang, Moon-Sung
    • Membrane Journal
    • /
    • v.27 no.5
    • /
    • pp.441-448
    • /
    • 2017
  • In this study, the effects of membrane characteristics on the power generation performance in reverse electrodialysis (RED) have been investigated with pore-filled ion-exchange membranes (PFIEMs) prepared by employing a porous polyethylene substrate and the mixtures of three cross-linking agents. As a result, it was confirmed through the correlation analyses that the cross-linking degree and free volume of the PFIEMs were effectively controlled by mixing the cross-linking agents having different molecular sizes, influencing complexly the electrochemical characteristics of the membranes and the power generation performance in RED. In particular, the pore-filled cation-exchange membranes at the optimum cross-linking conditions exhibited the power generation performance superior to that of the commercial membranes and the pore-filled anion-exchange membranes also showed the excellent performance close to that of the commercial membrane.

Development of a continuous electrolytic system with an ion exchange membrane for pH-control with only one discharge of electrolytic solution and its characteristics (단일 전해액 배출만을 가지는 pH조절용 연속식 이온 교환막 전해 시스템의 개발과 그 특성)

  • Kim Kwang-Wook;Kim In-Tae;Park Geun-Il;Lee Eil-Hee
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
    • /
    • v.3 no.4
    • /
    • pp.269-278
    • /
    • 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.

  • PDF

Preparation of Heterogeneous Ion Exchange Membranes and Evaluation of Desalination Performance in Capacitive Deionization (불균질 이온교환막의 제조와 축전식 탈염에서의 탈염 성능 평가)

  • Choi, Jae-Hwan;Lee, Joo-Bong
    • Membrane Journal
    • /
    • v.26 no.3
    • /
    • pp.229-237
    • /
    • 2016
  • We prepared heterogeneous ion exchange membranes (hetero-IEMs) for the application of membrane capacitive deionization (MCDI). Hetero-IEMs were fabricated by compressing the mixture of ion exchange resin powders and liner low density polyethylene (LLDPE). Characterization and MCDI desalination experiments were carried for the fabricated membranes. Electrical resistance of membrane decreased and water content increased with increasing the resin content in the hetero-IEMs. However, transport number indicating permselectivity of membrane was similar with that of commercial homogenesous ion exchange membrane. The results of MCDI desalination experiments showed that the adsorption amount for hetero-IEM was about 90% of that of homogeneous membrane due to the high electrical resistance of hetero-IEM. Although desalination performance of hetero-IEM decreased compared with homogeneous membrane, it was thought to be applicable to MCDI because of simple preparation and low price.

Research Trends and Prospects of Reverse Electrodialysis Membranes (역전기투석용 이온교환막의 연구동향 및 전망)

  • Hwang, Jin Pyo;Lee, Chang Hyun;Jeong, Yeon Tae
    • Membrane Journal
    • /
    • v.27 no.2
    • /
    • pp.109-120
    • /
    • 2017
  • The reverse electrodialysis (RED) is an energy generation system to convert chemical potential of saline water directly into electric energy via the combination of current derived from a redox couple electrolyte and ionic potential obtained when cation ($Na^+$) and anion ($Cl^-$) pass through cation exchange membrane (CEM) and anion exchange membrane (AEM) into fresh water, respectively. Ion exchange membrane, a key element of RED system, should satisfy requirements such as 1) low swelling behavior, 2) a certain level of ion exchange capacity, 3) high ion conductivity, and 4) high perm-selectivity to achieve high power density. In this paper, research trends and prospects of ionomer materials and ion exchange membranes are dealt with.

Development and Application of Cation-exchange Membranes Including Chelating Resin for Efficient Heavy-metal Ion Removal (효율적인 중금속 이온 제거를 위한 킬레이팅 수지를 포함한 양이온 교환막의 개발 및 응용)

  • Kim, Do-Hyeong;Choi, Young-Eun;Park, Jin-Soo;Kang, Moon-Sung
    • Membrane Journal
    • /
    • v.27 no.2
    • /
    • pp.129-137
    • /
    • 2017
  • In this study, we have developed cation-exchange membranes (CEMs) which can efficiently separate heavy-metal ions among the cations contained in a water system. Sulfonated polyetheretherketone (SPEEK) was used as a base polymer and a powdered chelating resin with strong binding ability to heavy-metal ions was added into it. In order to optimize the performance of the CEM, the content of chelating resin powder and the ion exchange capacity of SPEEK have been controlled. As a result, it was confirmed that the removal efficiency of heavy metal ion was improved by more than 20% by applying the CEM to membrane capacitive deionization (MCDI).

Recent Progress on Proton Exchange Membrane Based Water Electrolysis (수소이온 교환막 기반 수전해의 최근 연구 동향)

  • Yang, Seungmin;Rajkumar, Patel
    • Membrane Journal
    • /
    • v.32 no.5
    • /
    • pp.275-282
    • /
    • 2022
  • In contemporary days, hydrogen-based energies including batteries are renowned to be effective. And its effectiveness comes from the fact that it possesses high efficiency as an energy carrier. Eco-friendly and high purity of hydrogens comes out from water electrolysis. And among different types of electrolysis, proton exchange membrane (PEM) water electrolysis is considered the most renewable, cheap, and eco-friendly. It produces oxygen and hydrogens which are feasible in using as energies. Since it has such a number of benefits, increased research is going on in PEM electrolysis. Nafion is widely used as PEM, but high cost and various other disadvantages leads to the exploration of alternative materials. This review is broadly classified into Nafion and non Nafion based PEM for water electrolysis.

Preparation and Properties of Sufonated High Impact Polystyrene(HIPS) Cation Exchange Membrane Via Sulfonation (술폰화 반응에 의한 High impact polystyrene(HIPS) 양이온교환막의 제조 및 특성)

  • Kim, Yong-Tae;Kwak, Noh-Seok;Lee, Choul-Ho;Jin, Chang-Soo;Hwang, Taek-Sung
    • Korean Chemical Engineering Research
    • /
    • v.49 no.2
    • /
    • pp.211-217
    • /
    • 2011
  • In this study, ion exchange membranes were prepared using high impact polystyrene(HIPS) with various crosslinking and sulfonation time. Degree of sulfonation(DS) of sulfonated HIPS(SHIPS) membrane was increased with sulfonation time and decreased with crosslinking time. The highest value of DS was 66%. Also, water uptake and ion exchange capacity(IEC) of SHIPS membrane were decreased with degree of crosslinking and increased with sulfonation time. Then their values were 35.2% and 1.55 meq/g, respectively. Electrical resistance and ion conductivity of the membranes were showed more excellent value with sulfonation time. The maximum value of electrical resistance and ion conductivity were $0.4\Omega{\cdot}cm^{2}$ and 0.1 S/cm, respectively. It is indicated that the SHIPS membrane has the higher performance compare with Nafion 117. Durability of SHIPS membranes in a organic solvent was increased with increasing crosslinking time. The surface roughness of HIPS membranes were confirmed with SEM that was become uneven surface with progressing sulfonation.

Membrane Potential across Porous Anion-Exchange Membranes in Electrolyte Solution (전해질용액에서의 다공성 음이온교환막을 통한 막전위)

  • ;;Kiyono, Ryotaro;Tasaka, Masayasu
    • Proceedings of the Membrane Society of Korea Conference
    • /
    • 1997.04b
    • /
    • pp.21-22
    • /
    • 1997
  • 최근의 이온교환막은 종래의 양이온교환막의 표면에 polycation 등의 얇은 층을 덧붙인 다층막(multi-layer membrane)의 형태가 많이 이용되고 있으며, 정전기적 반발력의 차 등을 이용하여 원자가가 다른 이온들간의 투과성에 차를 부여하기 위하여 이용되고 있다. 이 때문에 polycation막을 통한 1가 이온과 2가 이온의 투과성을 연구하는 것은 우수한 이온교환막을 제작하는것 이상으로 중요하다. 본 연구에서는 고정전하농도(fixed charge density, $\Phi$ X)가 낮은 다공성 저전하음이온교환막을 제작하여, 양측에 대이온(counterion)은 같고 복이온(co-ion)이 다른 전해질용액을 두었을 경우에 관찰되는 막전위를 측정하였다. 이를 토대로 음이온교환막을 통한 막전위의 농도의존성에 관하여 검토하였으며, 비평형열역학(non-equilibrium thermodynamies)에 기초한 이론적 모델을 도입하여 실험치와 비교, 해석하였다.

  • PDF

Fouling of Ion Exchange Membranes and Their Fouling Mitigation (이온교환막의 막오염 및 오염저감)

  • 문승현;이홍주
    • Membrane Journal
    • /
    • v.12 no.2
    • /
    • pp.55-66
    • /
    • 2002
  • fouling phenomena of ion exchange membranes were reviewed for improved design and operation of electodialysis. The membrane fouling index for electrodialysis (EDMFI) was defined for the quantitative analysis of fouling potential as an analogy to the pressure-driven membrane process. fouling phenomena were compared in the electrodialysis experiments with inorganic foulant (silica sol) and organic foulants (humate and bovine serum albumin (BSA)), and their fouling potentials were analyzed using the fouling index. The comparison showed that the EDMFI could be used as a quantitative measure of the fouling tendency in electrodialysis processes. As a novel fouling mitigation method, square wave power was reported to be effective in electrodialysis with organic foulants. The square wave powers having the pulsed electric field enabled to reduce the membrane fouling significantly at an optimal frequency.

Molecular Dynamics (MD) Study of Proton Exchange Membranes for Fuel Cells (연료전지용 수소이온 교환막의 분자동역학 연구)

  • Park, Chi Hoon;Nam, Sang Yong;Hong, Young Taik
    • Membrane Journal
    • /
    • v.26 no.5
    • /
    • pp.329-336
    • /
    • 2016
  • Proton exchange membrane (PEM) is one of the key components of membrane-electrode assembly (MEA), which plays important role in fuel cell performance together with catalysts. It is widely accepted that water channel morphology inside PEMs as a proton pathway significantly affects the PEM performance. Molecular dynamics (MD) simulations are a very useful tool to understand molecular and atomic structures of materials, so that many related researches are currently being studied. In this paper, we summarize the current research trend in MD simulations, present which properties can be characterized, and finally introduce the usefulness of MD simulations to the researchers for proton exchange membranes.