Unlocking Advanced CO2 Separation via 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 to 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 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 selectivity ratios of CO2/N2 ~ 249 and CO2/CH4 ~199 at the 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.