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Title: Ultem®/ZIF-8 mixed matrix membranes for gas separation: Transport and physical properties

Mixed matrix membranes are promising options for improving gas separation processes. Zeolitic imidazolate frameworks (ZIFs) have a porous structure similar to conventional zeolites, being capable in principle of separating gases based on their differences in kinetic diameter while offering the advantage of having a partial organic character. This partial organic nature improves the compatibility between the sieve and the polymer, and a combination of the mentioned characteristics makes these hybrid materials interesting for the preparation of mixed matrix gas separation membranes. In this context the present work reports the preparation of Ultem®/ZIF-8 mixed matrix membranes and their permeabilities to pure CO2, N2 and CH4 gases. A significant increase in permeability with increase in CO2/N2 selectivity was observed for the mixed matrix systems as compared to the properties of the neat Ultem®. Sorption results allowed to speculate that the ZIF-8 framework is not completely stable dimensionally, what influences the separation process by allowing gases with higher kinetic diameter than its nominal aperture to be sorbed and to diffuse through the crystal. Lastly, sorption and diffusion selectivities indicate that the higher separation performance of the mixed matrix membranes is governed by the diffusion process associated with the influence of gas molecule´s geometry.
 [1] ;  [2] ;  [1]
  1. Univ. Federal de Sao Carlos, Sao Carlos (Brazil)
  2. Georgia Inst. of Technology, Atlanta, GA (United States)
Publication Date:
OSTI Identifier:
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Materials Research (Sao Carlos, Online)
Additional Journal Information:
Journal Name: Materials Research (Sao Carlos, Online); Journal Volume: 19; Journal Issue: 1; Journal ID: ISSN 1980-5373
Univerisdade Federale de Sao Carlos
Research Org:
Georgia Tech Research Corporation, Atlanta, GA (United States)
Sponsoring Org:
USDOE Advanced Research Projects Agency - Energy (ARPA-E)
Country of Publication:
United States
36 MATERIALS SCIENCE ZIF-8; mixed matrix membranes; gas separation; gas permeation; gas sorption