Enhancing hydrogen gas separation performance of thin film composite membrane through facilely blended polyvinyl alcohol and PEBAX

Polymeric membranes offer economic separation processes but are less explored for H-2 separation application. This work aims to unveil the H-2 separation potential of polymeric membrane by developing PVA-based reverse selective composite membrane. CO2-selective PEBAX was blended at different PVA:PEBAX ratio. The effect of PEBAX blending on membrane morphology, crystallinity and gas separation behavior was studied. Incorporation of PEBAX at <50 wt% resulted in composite with improved CO2 permeability but selectivity loss. Blending of >60 wt% PEBAX enhanced both permeance and selectivity of the resulted composite as the host matrix was dominated by this PEO containing material thus greatly enhancing polymer chain mobility and promoting CO2-solubility. The best composite which contains 60 wt% PEBAX exhibited CO2 permeability of 20.0 Barrer and CO2/H-2 selectivity of 7.6. This performance surpasses the Robeson's boundary and unleashes the potential of tailoring the properties of polymeric nanocomposite membrane for H-2 separation application through facile PVA/PEBAX blending. (c) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

The study developed a PVA-based reverse selective composite membrane by blending CO2-selective PEBAX, which improved both CO2 permeability and selectivity. The composite with 60 wt% PEBAX exhibited the best performance, surpassing traditional limits and offering a new approach for preparing polymeric membranes for H-2 separation applications.