• Title/Summary/Keyword: membrane transport

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Intrinsic Permeation Properties of Graphene Oxide Membranes for Gas and Ion Separations (그래핀옥사이드 멤브레인의 기체 및 이온 투과 특성)

  • Kim, Hyo Won
    • Membrane Journal
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    • v.32 no.1
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    • pp.1-12
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    • 2022
  • Graphene oxide (GO) has been considered as a promising membrane material, because of its easy processability and distinct properties, including controllable pore size distribution and diffusion channels. Particularly, the feasibility has been proposed a number of simulation results and proof-of-concept experimental approaches towards GO membranes. That is, GO already shows many outstanding intrinsic properties suitable for promising membrane platforms, such as the minimum membrane thickness and the ability to generate nanopores in the two-dimensional lattices or to create slit-like nanochannels between adjacent sheets. This review will be addressed the important experimental development in GO-based membranes for gas and ion separations, emphasizing on intrinsic transport phenomena, and critical issues for practical applications.

Transport Properties of Crosslinked Poly Vinyl Alcohol Membrane in Pervaporation

  • Lee, Chul-Haeng;Hong, Won-Hi
    • Proceedings of the Membrane Society of Korea Conference
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    • 1996.10a
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    • pp.92-93
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    • 1996
  • PVA membrane was widely used in the dehydration pervaporation process. PVA membrane showed remakable selectivity towed water and an excellent film-forming polymer, with a good resistance to orgamic solvents but it has poor stability in aqueous mixtures. Generally the PVA is manufactured by the hydrolysis reaction from poly vinyl acetate(PVAc) and so the degree of PVA hydrolysis is a major parameter for properties of PVA membrane such as the crystallinity and polarity.

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Separation of Two Amino Acids by Microemulsion Bulk Liquid Membrane

  • Salabat, Alireza;Sanij, Fereshteh Dehghani
    • Bulletin of the Korean Chemical Society
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    • v.33 no.10
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    • pp.3387-3390
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    • 2012
  • In this research work the potentialities of microemulsion bulk liquid membrane for the selective transport of L-tryptophan (L-Trp) and L-tyrosine (L-Tyr) are investigated at 298.15 K. Reversed micelle formed by sodium bis(2-ethylhexyl)sulfosuccinate (AOT) in dichloroethane, was used as mobile carrier to transport amino acids between a source and a receiving aqueous phase. The effects of pH, surfactant concentration and initial amino acid concentration on the extraction efficiency and transfer rate of the amino acids were studied. It is verified that for a mixture of two amino acids, L-Trp can be extracted selectively by using this type of the bulk liquid membrane with optimized condition.

Mechanisms of gas permeation through microporous membranes - A review

  • Hwang, Sun-Tak
    • Proceedings of the Membrane Society of Korea Conference
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    • 1995.09a
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    • pp.1-13
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    • 1995
  • A review is presented for various gas tranport mechanisms through microporous membranes of both polymeric and inorganic materials. Different transport modes manifest depending on the pore size and the flow regime, which is a function of pressure, temperature, and the inateraction between gas molecules and the pore walls. For microporous membranes whose pores are small and the intenal surface area huge, the surface diffusion becomes a significant factor. If the pores become even smaller, them the transport mechanism will be more of an activated diffusion type. When conditions are right capillary condensation will take place to create an enormous capillary pressure gradient, which will greatly enhance the permeation flux. At the same time the capillary condensate of the heavier component may block the membrane pores denying the passage of the lighter gas molecules. All of these phenomena will influence the separation of mixtures.

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Proton Exchange Membranes using Polymer Blends of PVA(Polyvinyl alcohol)/PSSA-MA(Polystyrene sulfonic acid-co-maleic acid)

  • Knag, Moon-Sung;Kim, Jong-Hak;Kim, Hyunyoo;Jongok Won;Moon, Seung-Hyeon;Kang, Yong-Soo
    • Proceedings of the Membrane Society of Korea Conference
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    • 2004.05a
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    • pp.29-32
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    • 2004
  • Reduction of methanol crossover in proton exchange membranes (PEMs) can be achieved by 1) the selection of materials, 2) the morphology control, and 3) the adequate crosslinking [1, 2]. The selection of polymer matrix of PEM for direct methanol fuel cells (DMFCs) is very important because the proton conductivity and methanol permeability are largely dependent upon the properties of polymers.(omitted)

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Effect of Amino Acids in Silver Polymer Electrolyte Membranes on Facilitated Olefin Transport

  • Kang, Sang-Wook;Kim, Jong-Hak;Jongok Won;Kookheon Char;Kang, Yong-Soo
    • Proceedings of the Membrane Society of Korea Conference
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    • 2004.05a
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    • pp.78-81
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    • 2004
  • Here the effect of various amino acids on the separation performance for these two contrastive membranes is investigated. It was especially focused on the structures of amino acids, and their effects on the silver ion activity as well as the interaction between polymer electrolytes and amino acid. The amino acids studied include asparagine, valine, glutamic acid and lysine.(omitted)

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The Structural Transitions of $\pi$-Complexes of Poly(styrene-b-butadiene-b-styrene) Block Copolymers with Silver Salts and Their Relation to Facilitated Olefin Transport

  • Lee, Dong-Hoon;Kim, Jong-Hak;Jongok Won;Kang, Yong-Soo
    • Proceedings of the Membrane Society of Korea Conference
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    • 2004.05a
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    • pp.211-215
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    • 2004
  • Olefins are the most important feedstock in the petrochemical industry and thus the separation of olefin/paraffin mixtures is crucial to that industry. At present, this separation is mostly carried out using cryogenic distillation processes that require enormous capital investment and have high operational costs.(omitted)

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Multicomponent Nanostructured Materials for Separation Membranes

  • Peinemann, Klaus-Viktor
    • Proceedings of the Membrane Society of Korea Conference
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    • 2004.05a
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    • pp.11-11
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    • 2004
  • Under the coordination of GKSS a new European project in the field of membrane development started recently. This project focuses on the development of novel nanostructured materials for selective material transport and separation. Two classes of materials will be developed in this project: nanostructured organic/inorganic hybrid materials and functional self-organized supramolecular copolymers.(omitted)

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The Effect of LSC/GDC (50 : 50 vol%) Active Layers on Oxygen Transport Properties of LSCF/GDC (20 : 80 vol%) Dual-phase Membrane (LSC/GDC (50 : 50 vol%) 활성층이 LSCF/GDC (20 : 80 vol%) 복합 분리막의 산소투과 거동에 미치는 영향)

  • Cha, Da-Som;Yoo, Chung-Yul;Joo, Jong Hoon;Yu, Ji Haeng;Han, Moon-Hee;Cho, Churl-Hee
    • Membrane Journal
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    • v.24 no.5
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    • pp.367-374
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    • 2014
  • In the present study, disc-type LSCF/GDC (20 : 80 vol%) dual-phase membranes having porous LSC/GDC (50 : 50 vol%) active layers were prepared and effect of active layers on oxygen ion transport behavior was investigated. Introduction of active layers improved drastically oxygen flux due to enhanced electron conductivity and oxygen surface exchange activity. As firing temperature of active layer increased from $900^{\circ}C$ to $1000^{\circ}C$, oxygen flux increased due to improved contact between membrane and active layer or between grains of active layer. The enhanced contact would improve oxygen ion and electron transports from active layer to membrane. Also, as thickness of active layer increased from 10 to $20{\mu}m$, oxygen flux decreased since thick active layer rather prevented oxygen molecules diffusing through the pores. And, STF infiltration improved oxygen flux due to enhanced oxygen reduction reaction rate. The experimental data announces that coating and property control of active layer is an effective method to improve oxygen flux of dual-phase oxygen transport membrane.