Hollow carbon fiber membranes for gas separation have been successfully fabricated for the first time by a special type of precursor. This precursor is dual-layer hollow fiber composed of a polysulfone-beta zeolite (PSF-beta) mixed matrix outer layer and a Matrimid inner layer. Pure gas permeation measurements show that the resultant hollow carbon fiber has O2/N2 and CO2/CH4 selectivities of 9.3 and 150, respectively; this performance is much better than that of the hollow carbon fiber derived from single-layer Matrimid hollow fiber. Mixed gas measurements show the CO2/CH4 selectivity of 128. After pyrolysis, the PSF-beta layer in the dual-layer precursor evolves into a continuous structure of closely packed zeolite particles embedded in the PSF carbon residue. TGA spectra suggest that the possible reason for the above observation is that the PSF-beta outer layer and Matrimid inner layer has significantly changed each other's pyrolysis dynamics and thermal degradation process.
ASJC Scopus subject areas
- Materials Chemistry