Preparation of Hierarchical Aramid Fiber Filtration Material for High-Efficiency Water Filtration

Fiber filtration technology provides an effective solution for removing fine particulate contaminants from the primary coolant in nuclear power plants. To overcome the trade-off between filtration efficiency and resistance, a hierarchical aramid fiber filtration material was developed by blending aramid nanofibers with pristine aramid pulp. Structural analysis shows that nanofibrils graft onto microscale pulp fibers via hydrogen bonding, forming a robust network where microfibers act as scaffolds and nanofibrils create a dense filtration matrix. Filtration tests reveal that the hierarchical aramid fiber filter achieves outstanding filtration performance with a low resistance of under 1500 Pa. Specifically, it exhibits a 99.99% filtration efficiency against 0.3 μm NaCl aerosols and 99.23% against 0.3 μm polystyrene particles. Moreover, after cumulative γ-irradiation and immersion in simulated nuclear wastewater, the filter retained its fibrous structure, high filtration efficiency, and satisfactory mechanical properties, demonstrating remarkable durability. This study presents a strategy for the design of high-performance nuclear-grade water filtration materials.