• Membrane Journal
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• v.25 no.2
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• pp.107-114
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• 2015

PTMSP-NaA zeolite composite membranes were prepared by adding 0~50 wt% NaA zeolite to PTMSP. The membranes were characterized by FT-IR, $^1H$-NMR, GPC, DSC, TGA, SEM. The permeabilities of $H_2$ and $N_2$ gases through PTMSP-NaA zeolite composite membranes was studied as a function of NaA zeolite contents. According to TGA measurements, when zeolite was inserted into the polymer, weight loss temperature and weight loss wt% of PTMSP-NaA zeolite composite membranes were decreased. Based on SEM observation, NaA zeolite was dispersed in the PTMSP-NaA zeolite composite membrane with the size $2{\sim}5{\mu}m$. The permeability of PTMSP-NaA zeolite composite membranes increased added as NaA zeolite content increased. On the contrary, the selectivity ($H_2/N_2$) of the composite membranes decreased as NaA zeolite content increased. PTMSP-NaA zeolite composite membrane showed better permeability and selectivity ($H_2/N_2$) of $H_2$ and $N_2$ than PTMSP-NaY zeolite composite membrane.

• Membrane Journal
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• v.25 no.3
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• pp.295-300
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• 2015

PDMS-NaA zeolite membranes were prepared by adding 0~40 wt% NaA zeolite. Based on SEM observation, NaA zeolite was dispersed in the PDMS-NaA zeolite membranes with $2{\sim}5{\mu}m$. The permeabilities of $H_2$ and $N_2$ gases through PDMS-NaA zeolite membranes increased as NaA zeolite contents increased and $H_2$ gas had better permeabilities than $N_2$. The selectivity ($H_2/N_2$) of PDMS-NaA zeolite membranes increased as NaA zeolite contents increased.

• Korean Membrane Journal
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• v.2 no.1
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• pp.48-55
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• 2000

In order to improve organic vapor separation efficiency of polydimethylsiloxane (PDMS) membrane, various zeolites (zeolite 4A, zeolite 13X and natural zeolite) were introduced into a thin PDMS film. The measurements of permeability and selectivity of zeolite-filled PDMS membranes were carried out with a CO$_2$gas and a CO$_2$gas/acetic acid vapor mixture, respectively. The CO$_2$permeability of zeolite-filled membranes decreased with increasing zeolite content and then recovered up to 30 wt% content. The effect of zeolite type on the improvement of CO$_2$permeability was found to be in the order of zeolite 13X > natural zeolite > 4A. The CO$_2$selectivity of zeolite-filled membranes was enhanced up to 9 times compared with the selectivity of a pure (unfilled) PDMS membrane. The effect of zeolite type on the improvement of CO$_2$selectivity was found to be in the order of natural zeolite > zeolite 13X > zeolite 4A.

• Membrane Journal
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• v.22 no.5
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• pp.342-351
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• 2012

In this study, PTMSP[poly(1-trimethylsilyl-1-propyne)]/PDMS[poly(dimethylsioxane)]-NaY zeolite and PTMSP/PDMS-NaA zeolite composite membranes were made to incorporate zeolite into PTMSP/PDMS graft copolymer in order to improve the selectivity and thermal stability, the drop of permeability by physical aging effect during long period of time for the PTMSP membrane. To investigate the physico-chemical characteristics of composite membranes, the analytical methods such as FT-IR, $^1H$-NMR, TGA, SEM, and GPC have been utilized. The gas permeability and selectivity properties of $H_2$ and $N_2$ were evaluated. The permeability of the PTMSP/PDMS-NaY zeolite and PTMSP/PDMS-NaA zeolite composite membranes than PTMSP/PDMS graft copolymer membrane increased, increased as zeolite content increased. On the contrary, the selectivity ($H_2/N_2$) of the composite membranes decreased as zeolite content increased. PTMSP/PDMS-NaA zeolite composite membrane showed better permeability and separation factor than PTMSP/PDMS-NaY zeolite composite membrane.

• Proceedings of the Membrane Society of Korea Conference
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• 1997.10a
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• pp.5-8
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• 1997

Introduction : Membranes made from inorganic materials are generally superior to organo-polymeric materials in thermal and mechanical stability, and chemical resistance. Among inorganic materials zeolite is a promising candidate for a high performance membrane because of the unique characteristics of zeolite crystals such as molecular sieving, ion exchange, selective adsorption and catalysis. Although there are many recent reportsl on the preparation of zeolitc membranes and the gas permeation through the membranes, only a limited number of publications deal with pervaporation studies. Recently, we have reported a high pervaporation performance of NaA zeolite membrane for the separation of water/organic liquid mixtures. and of NaY zeolite menlbrane for the separation of methanol/MTBE. Here, preparation of zeolite (LTA, ZSM-5 and FAU) membranes and their permeation properties are discussed.

• Korean Chemical Engineering Research
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• v.43 no.6
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• pp.691-695
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• 2005

Zeolite membranes on various supports such as filter paper, cotton fiber, and glass fiber filter were prepared by secondary growth hydrothermal synthesis. First, zeolite NaA (${\approx}0.5{\mu}m$) and silicalite-1 (${\approx}0.2{\mu}m$) crystals were synthesized as zeolite seed crystals, and they were attached to the surfaces of the supports via chemical bonding. Zeolite NaA or silicalite-1 membranes could be synthesized on the supports coated with the seed crystals. The prepared zeolite membranes were observed by scanning electron microscope and analyzed by X-ray diffraction.

• Korean Chemical Engineering Research
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• v.44 no.3
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• pp.243-247
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• 2006

MFI zeolite membranes were prepared on anodic alumina (Anodisc) as support. First, silicalite-1(${\approx}1.2{\mu}m$) seed crystals were attached to the surface of the support via chemical bonding, and the a- and b-axis oriented zeolite membranes could be synthesized on the support coated with the monolayer of the seed crystals by secondary growth hydrothermal synthesis. The zeolite membranes prepared were characterized using scanning electron microscope and analyzed by X-ray diffraction.

• Membrane Journal
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• v.24 no.4
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• pp.285-291
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• 2014

The PTMSP[Poly(1-trimethylsilyl-1-propyne)]-NaY zeolite composite membranes were prepared by adding 0~50 wt% NaY zeolite to PTMSP. In order to investigate the characteristics of these membranes, we used the analytical methods such as FT-IR, $^1H$-NMR, GPC, DSC, TGA, and SEM. Gas permeation experiments were carried out at $23{\sim}26^{\circ}C$, $2kgf/cm^2$, and the permselectivity of $H_2$ and $N_2$ gases through the composite membranes was studied as a function of the NaY zeolite contents. According to TGA measurements, when NaY zeolite was inserted within the PTMSP, thermal stability of PTMSP was enhanced. Based on SEM observation, NaY zeolite was dispersed in the PTMSP-NaY zeolite composite membrane with a size of $1.5{\mu}m$. The permeability of $H_2$ and $N_2$ through the PTMSP-NaY zeolite composite membranes increased as NaY zeolite content increased. On the contrary, the selectivity($H_2/N_2$) of the PTMSP-NaY zeolite composite membranes decreased as zeolite content increased.

• Applied Chemistry for Engineering
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• v.16 no.1
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• pp.61-67
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• 2005

Zeolite membranes show better thermal, mechanical, chemical stabilities than polymer membranes. Water was separated from water/ethanol mixtures by pervaporation using the NaA and the NaY zeolite membranes synthesized in our laboratory. The effects of concentration of ethanol at the feed side and temperature were studied on the permeation flux and separation factor of water. The separation factors obtained with the NaA zeolite membrane was found to be 1000 times higher than those obtained with the NaY. However, the water flux through the NaA zeolite membrane was observed to be lower than 1/2 of that through the NaY zeolite membrane.

• Membrane Journal
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• v.25 no.1
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• pp.42-47
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• 2015

In this study, PEBAX[poly(ether-block-amide)]-NaY zeolite composite membranes were prepared, and those prepared membranes were studied on permeability of $C_3H_6$ and $C_3H_8$, and selectivity ($C_3H_6/C_3H_8$). NaY zeolite particles in PEBAX-NaY zeolite composite membranes was dispersed as aggregated particles with the size $0.5{\sim}2.5{\mu}m$ by SEM observation. TGA measurement showed the weight loss change resulted from the amount of NaY zeolite when NaY zeolite was added into PEBAX. By gas permeation experiment, the permeabilities of $C_3H_6$ and $C_3H_8$ were decreased by the more addition NaY zeolite in PEBAX. Overall, $C_3H_6$ was having higher permeability than $C_3H_8$. The selectivity $C_3H_6/C_3H_8$ was decreased by the more NaY zeolite in PEBAX.