Unlocking advanced CO2 separation via a scalable and nitrogen-rich MOF-cross-linked polydimethylsiloxane hollow fiber hybrid membrane

Abstract

Addressing the urgent need for innovative solutions to combat climate change, this study introduces a groundbreaking approach for the selective separation of carbon dioxide (CO₂) from the industrial flue and biogas streams. By leveraging the unique properties of Metal–Organic Frameworks (MOFs) and the versatility of polydimethylsiloxane (PDMS), we developed a hybrid membrane that stands at the forefront of CO₂ separation technology. At the core of our innovation is the strategic incorporation of a moisture-stable, Zn(II) (aminoiosphtalic)(4,4′,4′′-(1H-imidazole-2,4,5-triyl)tripyridine) MOF into a cross-linked polymethylsiloxane layer. This composite membrane, with a thickness of up to 25 μm, is fabricated over asymmetric polysulfone hollow fibers, resulting in a robust platform that showcases exceptional ideal selectivity and efficiency in CO₂ separation. This hybrid membrane distinguishes itself from other adsorbents by demonstrating CO₂ flux values ranging from 50 to 240 gas permeation unit under gauge pressures of 10–100 kPa, and achieving unparalleled ideal selectivity ratios of CO₂/N₂ ∼ 249 and CO₂/CH₄ ∼ 199 at a minimal pressure of 10 kPa. The membrane's exceptional recyclable performance, coupled with the simplicity of fabrication marks a significant advancement in the field of gas separation. The present findings pave the way for next-generation carbon capture technologies and align with the global imperative for cleaner industrial processes.