Nanoporous layered silicate AMH-3/cellulose acetate nanocomposite membranes for gas separations

Handle URI:
http://hdl.handle.net/10754/598946
Title:
Nanoporous layered silicate AMH-3/cellulose acetate nanocomposite membranes for gas separations
Authors:
Kim, Wun-gwi; Lee, Jong Suk; Bucknall, David G.; Koros, William J.; Nair, Sankar
Abstract:
Nanoporous layered silicate/polymer composite membranes are of interest because they can exploit the high aspect ratio of exfoliated selective flakes/layers to enhance molecular sieving and create a highly tortuous transport path for the slower molecules. In this work, we combine membrane synthesis, detailed microstructural characterization, and mixed gas permeation measurements to demonstrate that nanoporous flake/polymer membranes allows significant improvement in gas permeability while maintaining selectivity. We begin with the primary-amine-intercalated porous layered silicate SAMH-3 and show that it can be exfoliated using a high shear rate generated by a high-speed mixer. The exfoliated SAMH-3 flakes were used to form SAMH-3/cellulose acetate (CA) membranes. Their microstructure was analyzed by small angle X-ray scattering (SAXS), revealing a high degree of exfoliation of AMH-3 layers in the CA membrane with a small number of layers (4-8) in the exfoliated flakes. TEM analysis visualized the thickness of the flakes as 15-30nm, and is consistent with the SAXS analysis. The CO2/CH4 gas separation performance of the CA membrane was significantly increased by incorporating only 2-6wt% of SAMH-3 flakes. There was a large increase in CO2 permeability with maintenance of selectivity. This cannot be explained by conventional models of transport in flake-containing membranes, and indicates complex transport paths in the membrane. It is also in contrast to the much higher loadings of isotropic particles required for similar enhancements. The present approach may allow avoidance of particle aggregation and poor interfacial adhesion associated with larger quantities of inorganic fillers. © 2013 Elsevier B.V.
Citation:
Kim W, Lee JS, Bucknall DG, Koros WJ, Nair S (2013) Nanoporous layered silicate AMH-3/cellulose acetate nanocomposite membranes for gas separations. Journal of Membrane Science 441: 129–136. Available: http://dx.doi.org/10.1016/j.memsci.2013.03.044.
Publisher:
Elsevier BV
Journal:
Journal of Membrane Science
KAUST Grant Number:
KUS-I1-011-21
Issue Date:
Aug-2013
DOI:
10.1016/j.memsci.2013.03.044
Type:
Article
ISSN:
0376-7388
Sponsors:
This publication is based on work supported by Award No. KUS-I1-011-21, made by King Abdullah University of Science and Technology (KAUST). We acknowledge J.-H. Kang (Georgia Tech) for assistance with preparing Figs. 1 and 7.
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Publications Acknowledging KAUST Support

Full metadata record

DC FieldValue Language
dc.contributor.authorKim, Wun-gwien
dc.contributor.authorLee, Jong Suken
dc.contributor.authorBucknall, David G.en
dc.contributor.authorKoros, William J.en
dc.contributor.authorNair, Sankaren
dc.date.accessioned2016-02-25T13:44:14Zen
dc.date.available2016-02-25T13:44:14Zen
dc.date.issued2013-08en
dc.identifier.citationKim W, Lee JS, Bucknall DG, Koros WJ, Nair S (2013) Nanoporous layered silicate AMH-3/cellulose acetate nanocomposite membranes for gas separations. Journal of Membrane Science 441: 129–136. Available: http://dx.doi.org/10.1016/j.memsci.2013.03.044.en
dc.identifier.issn0376-7388en
dc.identifier.doi10.1016/j.memsci.2013.03.044en
dc.identifier.urihttp://hdl.handle.net/10754/598946en
dc.description.abstractNanoporous layered silicate/polymer composite membranes are of interest because they can exploit the high aspect ratio of exfoliated selective flakes/layers to enhance molecular sieving and create a highly tortuous transport path for the slower molecules. In this work, we combine membrane synthesis, detailed microstructural characterization, and mixed gas permeation measurements to demonstrate that nanoporous flake/polymer membranes allows significant improvement in gas permeability while maintaining selectivity. We begin with the primary-amine-intercalated porous layered silicate SAMH-3 and show that it can be exfoliated using a high shear rate generated by a high-speed mixer. The exfoliated SAMH-3 flakes were used to form SAMH-3/cellulose acetate (CA) membranes. Their microstructure was analyzed by small angle X-ray scattering (SAXS), revealing a high degree of exfoliation of AMH-3 layers in the CA membrane with a small number of layers (4-8) in the exfoliated flakes. TEM analysis visualized the thickness of the flakes as 15-30nm, and is consistent with the SAXS analysis. The CO2/CH4 gas separation performance of the CA membrane was significantly increased by incorporating only 2-6wt% of SAMH-3 flakes. There was a large increase in CO2 permeability with maintenance of selectivity. This cannot be explained by conventional models of transport in flake-containing membranes, and indicates complex transport paths in the membrane. It is also in contrast to the much higher loadings of isotropic particles required for similar enhancements. The present approach may allow avoidance of particle aggregation and poor interfacial adhesion associated with larger quantities of inorganic fillers. © 2013 Elsevier B.V.en
dc.description.sponsorshipThis publication is based on work supported by Award No. KUS-I1-011-21, made by King Abdullah University of Science and Technology (KAUST). We acknowledge J.-H. Kang (Georgia Tech) for assistance with preparing Figs. 1 and 7.en
dc.publisherElsevier BVen
dc.subjectAMH-3en
dc.subjectCO2 separationen
dc.subjectComposite membraneen
dc.subjectExfoliationen
dc.subjectInterfaceen
dc.subjectLayered silicatesen
dc.titleNanoporous layered silicate AMH-3/cellulose acetate nanocomposite membranes for gas separationsen
dc.typeArticleen
dc.identifier.journalJournal of Membrane Scienceen
dc.contributor.institutionGeorgia Institute of Technology, Atlanta, United Statesen
dc.contributor.institutionKorea Institute of Science and Technology, Seoul, South Koreaen
kaust.grant.numberKUS-I1-011-21en
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