Carbon hollow fiber membranes for a molecular sieve with precise-cutoff ultramicropores for superior hydrogen separation.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 33431865.
- Also identified by DOI 10.1038/s41467-020-20628-9 and PMC identifier 7801458.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Carbon molecular sieve (CMS) membranes with rigid and uniform pore structures are ideal candidates for high temperature- and pressure-demanded separations, such as hydrogen purification from the steam methane reforming process. Here, we report a facile and scalable method for the fabrication of cellulose-based asymmetric carbon hollow fiber membranes (CHFMs) with ultramicropores of 3-4 Å for superior H<sub>2</sub> separation. The membrane fabrication process does not require complex pretreatments to avoid pore collapse before the carbonization of cellulose precursors. A H<sub>2</sub>/CO<sub>2</sub> selectivity of 83.9 at 130 °C (H<sub>2</sub>/N<sub>2</sub> selectivity of >800, H<sub>2</sub>/CH<sub>4</sub> selectivity of >5700) demonstrates that the membrane provides a precise cutoff to discriminate between small gas molecules (H<sub>2</sub>) and larger gas molecules. In addition, the membrane exhibits superior mixed gas separation performances combined with water vapor- and high pressure-resistant stability. The present approach for the fabrication of high-performance CMS membranes derived from cellulose precursors opens a new avenue for H<sub>2</sub>-related separations.