Membrane-Based Air Filtration Technology for Environmental Suspended Particulate Separation

As global air pollution problems become increasingly severe, membrane-based filtration technology has become an important research direction for separating environmental suspended matter (Particulate Matter, PM). A review paper published in December 2025 by Polymers (MDPI) systematically reviews the application and development trends of various membrane technologies in PM separation.

The research covers five major membrane technology types: The first type is nanofiber membranes (Nanofiber Membranes), manufactured through electrospinning, featuring high specific surface area and adjustable pore size, achieving over 99.9% filtration efficiency for PM2.5 while maintaining low pressure drop. The second type is microporous membranes (Microporous Membranes), such as PTFE and PVDF membranes, using precisely controlled pore sizes for surface filtration, capable of water washing and regeneration. The third type is Janus membranes, with different hydrophilicity properties on dual faces, simultaneously achieving particle filtration and moisture management.

The fourth type is photocatalytic membranes (Photocatalytic Membranes), integrating photocatalytic materials like TiO₂ or ZnO into filter membranes. While filtering particles, utilizing photocatalytic reactions to decompose VOCs and harmful gases, achieving "filtration plus purification" dual functionality. The fifth type is hollow fiber membranes (Hollow Fiber Membranes), using tubular structure to provide extreme filtration area ratio, particularly suitable for industrial-scale large-volume filtration applications.

The paper particularly emphasizes future development directions of membrane technology include: antimicrobial function integration (such as nano-silver or copper ion coatings), flame-retardant performance enhancement (meeting building ventilation safety requirements), and reusable design (reducing material costs and environmental burden). These research findings have important reference value for air filter manufacturers in new material development and product innovation.