A simple ZnO-embedded method to prepare flexible ZIF-8 composite PESf hollow fiber membrane

Abstract

Highly flexible PESf-HF(hollow fiber)-supported ZIF-8 membrane was synthesized through a ZnO-embedded homologous seed induction method involving preparation of ZnO-containing-PESf-HF and growth of ZIF-8 on the outer-surface of PESf-HF with I.D. and O.D. of ∼1.9 mm and ∼2.5 mm. ZIF-8 membrane exhibited favorable molecular-sieve property of H2 over other gases. ZnO particles inside PESf-HF were used as nucleation and anchoring sites for ZIF-8 membrane growth to embed the membrane into support, which enhanced the binding strength between membrane and PESf-HF, thus obtaining excellent membrane stability and reproducibility. Because of this, the membrane displayed constant H2 permeance (∼1.06 × 10−7 mol·m−2·s−1·Pa−1) and H2/CO2 ideal selectivity (∼5.46) during the 1800 min-run.