Carbon hollow fiber membranes for a molecular sieve with precise-cutoff ultramicropores for superior hydrogen separation
Linfeng Lei, Fengjiao Pan, Arne Lindbråthen, Xiangping Zhang, Magne Hillestad, Yi Nie, Lu Bai, Xuezhong He, Michael D. Guiver
Abstract
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 2 separation. The membrane fabrication process does not require complex pretreatments to avoid pore collapse before the carbonization of cellulose precursors. A H 2 /CO 2 selectivity of 83.9 at 130 °C (H 2 /N 2 selectivity of >800, H 2 /CH 4 selectivity of >5700) demonstrates that the membrane provides a precise cutoff to discriminate between small gas molecules (H 2 ) 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 2 -related separations.