Unexpectedly Strong Size-Sieving Ability in Carbonized Polybenzimidazole for Membrane H₂/CO₂ Separation

Journal Article · Thu Nov 21 00:00:00 EST 2019 · ACS Applied Materials and Interfaces

DOI:https://doi.org/10.1021/acsami.9b16966· OSTI ID:1601453

Omidvar, Maryam ^[1]; Nguyen, Hien ^[2]; Huang, Liang ^[2]; Doherty, Cara M. ^[3]; Hill, Anita J. ^[3]; Stafford, Christopher M. ^[4]; Feng, Xianshe ^[5]; Swihart, Mark T. ^[2]; Lin, Haiqing ^[2]

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1. State Univ. of New York (SUNY), Buffalo, NY (United States); University at Buffalo, SUNY
2. State Univ. of New York (SUNY), Buffalo, NY (United States)
3. Commonwealth Scientific and Industrial Research Organization (CSIRO) Future Industries, Clayton, SV (Australia)
4. National Inst. of Standards and Technology (NIST), Gaithersburg, MD (United States)
5. Univ. of Waterloo, ON (Canada)

Polymers with high permeability and strong size-sieving ability are needed for H₂/CO₂ separation at temperatures ranging from 100 to 300 °C to enable an energy-efficient precombustion CO₂ capture process. However, such polymers usually suffer from a permeability/selectivity tradeoff, that is, polymers with high permeability tend to exhibit a weak size-sieving ability and thus low selectivity. In this work, we demonstrate that carbonization of a suitable polymer precursor (i.e., polybenzimidazole or PBI) generates microcavities (leading to high H₂ permeability) and ultramicroporous channels (leading to strong size-sieving ability and thus high H₂/CO₂ selectivity). Specifically, carbonization of PBI at 900 °C (CMS@900) doubles H₂ permeability and increases H₂/CO₂ selectivity from 14 to 80 at 150 °C. When tested with simulated syngas-containing equimolar H₂ and CO₂ in the presence of water vapor for 120 h, CMS@900 exhibits stable H₂ permeability of ≈36 barrer and H₂/CO₂ selectivity of ≈53 at 150 °C, above Robeson’s 2008 upper bound and demonstrating robustness against physical aging and CO₂ plasticization.

• Research Organization: State Univ. of New York (SUNY), Buffalo, NY (United States)
• Sponsoring Organization: USDOE Office of Fossil Energy (FE), Clean Coal and Carbon Management
• Grant/Contract Number: FE0031636
• OSTI ID: 1601453
• Alternate ID(s): OSTI ID: 1864402
• Journal Information: ACS Applied Materials and Interfaces, Journal Name: ACS Applied Materials and Interfaces Journal Issue: 50 Vol. 11; ISSN 1944-8244
• Publisher: American Chemical Society (ACS)
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
H2/CO2 separation
carbon capture
carbon molecular sieve membranes
hydrogen production
polybenzimidazole