Abstract
The increasing demand for hydrogen production has necessitated the development of H2-selective membranes. Polyimides are excellent membrane materials for gas separation; however, commercial polyimides generally lack sufficient H2 selectivity due to their low H2 affinity. Understanding the relationship between gas transport properties and free volume microstructure is critical to advancing H2-selective membrane design. Herein, we report a facile material strategy to adjust the free volume characteristics and H2 separation performance via blending Matrimid (PI) and crosslinkable resorcinol-based phthalonitrile prepolymer (RPN) with electron donor/acceptor properties. The novel RPN30/PI70 membrane exhibits H2/N2 and H2/CO2 permselectivity of 1637 and 66.4, respectively, with H2 permeability of 2.7 Barrer in pure gas test, surpassing Robeson upper bounds (2008). The increased H2 permselectivity of RPN/PI membranes was attributed to the narrowed free volume size and distribution, giving rise to the considerably improved H2 solubility and selectivity of the blends. Moreover, the H2 permeability of crosslinked RPN30/PI70 membranes can be further improved via thermal treatment. The H2/CO2 mixed-gas test reveals that the H2 gas separation performance of the RPN30/PI70 membrane is influenced by plasticization effect and competitive sorption. This study demonstrates a new versatile strategy for designing high-performance hydrogen-selective polymeric membranes.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.