Title: Benchmark CO₂ separation achieved by highly fluorinated nanoporous molecular sieve membranes from nonporous precursor via in situ cross-linking

Abstract

Molecular sieve membranes with rigid micropores and CO₂-philic functionalities within the architectures are promising candidates in CO₂ separation. However, the development of ctieve approaches for their fabrication still remains a significant challenge. In this study, an in situ cross-linking strategy is developed for the preparation of nanoporous fluorinated moleffecular sieve membranes using commercially available dense and non-porous polystyrene (M_PS) as a precursor template. Based on the dehydrative Friedel-Crafts reactions with highly fluorinated benzylic alcohols, M_PS membranes are cross-linked in situ upon exposure to Brønsted acid (CF₃SO₃H), affording fluorinated microporous polymeric membranes with surface areas up to 523 m² g^–1 and the presence of micropores centered at 1.1–1.3 nm as well as ultra-micropores (~0.6 nm). The obtained modified membranes exhibit good ideal CO₂ permeability of 797 barrer and CO₂/N₂ selectivity of 28.5. In addition, high fluorine content (up to 28.5 wt%) and good thermal stability made the cross-linked membranes promising candidates to produce fluorinated carbon molecular sieve membranes with improved textural properties, exhibiting surface areas up to 1020 m² g^–1 and ultra-micropores of ~0.4 nm. These membranes achieve superior CO₂/N₂ separation performances exceeding the Robeson upper bound limit (2008).

Authors:

Yang, Zhenzhen ^[1]; Guo, Wei ^[2]; Chen, Hao ^[2]; Kobayashi, Takeshi  ^[3];

• Search DOE PAGES for author "Kobayashi, Takeshi"
• Search DOE PAGES for ORCID "0000-0002-6366-0925"

Suo, Xian ^[2]; Wang, Tao  ^[1];

• Search DOE PAGES for author "Wang, Tao"
• Search DOE PAGES for ORCID "0000-0001-5004-160X"

Wang, Song ^[4]; Cheng, Long ^[5]; Liu, Gongping ^[5]; Jin, Wanqin ^[5]; Mahurin, Shannon M.  ^[1];

• Search DOE PAGES for author "Mahurin, Shannon M."
• Search DOE PAGES for ORCID "0000-0003-3792-1631"

Jiang, De-en ^[4]; Popovs, Ilja  ^[1];

• Search DOE PAGES for author "Popovs, Ilja"
• Search DOE PAGES for ORCID "0000-0002-9767-3353"

Dai, Sheng  ^[6]

• Search DOE PAGES for author "Dai, Sheng"
• Search DOE PAGES for ORCID "0000-0002-8046-3931"

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+ Show Author Affiliations

1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Chemical Sciences Division
2. Univ. of Tennessee, Knoxville, TN (United States)
3. Ames Lab., and Iowa State Univ., Ames, IA (United States)
4. Univ. of California, Riverside, CA (United States)
5. Nanjing Tech University (China)
6. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Chemical Sciences Division; Univ. of Tennessee, Knoxville, TN (United States)

Publication Date:

Sun Aug 08 00:00:00 EDT 2021

Research Org.:

Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ames Lab., Ames, IA (United States)

Sponsoring Org.:

USDOE Office of Science (SC), Basic Energy Sciences (BES). Chemical Sciences, Geosciences & Biosciences Division; USDOE Office of Science (SC), Basic Energy Sciences (BES)

OSTI Identifier:

1814265

Alternate Identifier(s):

OSTI ID: 1817629; OSTI ID: 1868614

Report Number(s):

IS-J-10,566
Journal ID: ISSN 0376-7388

Grant/Contract Number:  

AC05-00OR22725; AC02-07CH11358

Resource Type:

Accepted Manuscript

Journal Name:

Journal of Membrane Science

Additional Journal Information:

Journal Volume: 638; Journal ID: ISSN 0376-7388

Publisher:

Elsevier

Country of Publication:

United States

Language:

English

Subject:

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; molecular sieve membrane; cross-linking; ultramicropore; fluorine; CO2 separation