Recent progress and prospects of polymeric hollow fiber membranes for gas application, and water vapor and particulate matter removal

The increasing challenges in meeting the clean air demand have fuelled growing environmental awareness to secure effective air purification and separation techniques. Membrane separation has drawn interdisciplinary attention and has emerged as an indispensable gas purification technology. Nevertheless, the permeance/selectivity trade-off relationship, plasticization and physical aging are the main challenges in developing a promising membrane. There has been a substantial advancement in hollow fiber membranes in the last 10 years, owing to the attractive characteristics that favor industrial applications. In this review, we provide a critical summary of the latest discoveries of state-of-the-art polymeric hollow fiber membranes. The theoretical principles of spinning parameters and fabrication strategies on the membranes' final morphology and separation performance will be presented and discussed according to respective gas separation applications, namely CO2 capture, air purification, and hydrogen and propane/propylene separation. Besides, the latest progress in sulfur dioxide, hydrogen sulfide, water vapor and particulate matter removal will be discussed. The emerging R&D areas, particularly CO2-induced plasticization, physical aging and green solvents, will be highlighted. Lastly, this review will be concluded with challenges, perspectives and future directions. It is anticipated that this comprehensive review may stimulate a new research platform for developing next-generation gas separation hollow fiber membranes for sustainable energy and environmental applications.