Title: Fluidic Processing of High-Performance ZIF-8 Membranes on Polymeric Hollow Fibers: Mechanistic Insights and Microstructure Control

Abstract

Recently, a methodology for fabricating polycrystalline metal-organic framework (MOF) membranes has been introduced – referred to as interfacial microfluidic membrane processing – which allows parallelizable fabrication of MOF membranes inside polymeric hollow fibers of microscopic diameter. Such hollow fiber membranes, when bundled together into modules, are an attractive way to scale molecular sieving membranes. The understanding and engineering of fluidic processing techniques for MOF membrane fabrication are in their infancy. Here in this work, a detailed mechanistic understanding of MOF (ZIF-8) membrane growth under microfluidic conditions in polyamide-imide hollow fibers is reported, without any intermediate steps (such as seeding or surface modification) or post-synthesis treatments. A key finding is that interfacial membrane formation in the hollow fiber occurs via an initial formation of two distinct layers and the subsequent rearrangement into a single layer. This understanding is used to show how nonisothermal processing allows fabrication of thinner (5 μm) ZIF-8 films for higher throughput, and furthermore how engineering the polymeric hollow fiber support microstructure allows control of defects in the ZIF-8 membranes. Finally, the performance of these engineered ZIF-8 membranes is then characterized, which have H₂/C₃H₈ and C₃H₆/C₃H₈ mixture separation factors as high as 2018 and 65, respectively, and C₃H₆more » permeances as high as 66 GPU.« less

Authors:

Eum, Kiwon ^[1]; Rownaghi, Ali ^[2]; Choi, Dalsu ^[1]; Bhave, Ramesh R. ^[3]; Jones, Christopher W. ^[1]; Nair, Sankar ^[1]

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+ Show Author Affiliations

1. Georgia Inst. of Technology, Atlanta, GA (United States). School of Chemical and Biomolecular Engineering
2. Georgia Inst. of Technology, Atlanta, GA (United States). School of Chemical and Biomolecular Engineering; Missouri Univ. of Science and Technology, Rolla, MO (United States). Department of Chemical and Biochemical Engineering
3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science and Technology Division

Publication Date:

Wed Jun 01 00:00:00 EDT 2016

Research Org.:

Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)

Sponsoring Org.:

USDOE; Work for Others (WFO)

OSTI Identifier:

1356956

Grant/Contract Number:  

AC05-00OR22725

Resource Type:

Accepted Manuscript

Journal Name:

Advanced Functional Materials

Additional Journal Information:

Journal Volume: 26; Journal Issue: 28; Journal ID: ISSN 1616-301X

Publisher:

Wiley

Country of Publication:

United States

Language:

English

Subject:

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; 36 MATERIALS SCIENCE