High-Efficiency Capture and Recovery of Anionic Perfluoroalkyl Substances from Water Using PVA/PDDA Nanofibrous Membranes with Near-Zero Energy Consumption

Poly- and perfluoroalkyl substances (PFASs) have caused severe public concerns due to their toxicity and extensive occurrence in the aquatic environment. This study reports a highly porous amine-functionalized membrane for the rapid capture of GenX and other anionic PFASs [e.g., perfluorooctanesulfonate (PFOS) and perfluorooctanoic acid (PFOA)] from contaminated water with near-zero energy consumption. The optimized membrane, prepared by electrospinning of polydiallyldimethylammonium chloride using cross-linked poly(vinyl alcohol) as a binder, had a high water permeability of similar to 2700 L m(-2) h(-1) kPa(-1). This high permeability enabled rapid gravity-driven filtration of contaminated water with a merely 5 cm water head, corresponding to an estimated energy consumption of as little as 2.7 x 10(-4) kWh/m(3). Meanwhile, the membrane showed highly efficient capture of GenX (>97%), PFOS (>99%), and PFOA (>99%). A large capture capacity of 1.2 x 10(6) mu g/m(2) was demonstrated for GenX. The captured GenX was recovered and concentrated with a small-volume NaCl/methanol solution, which simultaneously regenerated the membrane for its reuse. Over a 12-cycle capture-recovery test, the membrane demonstrated a high GenX recovery ratio of 94% and a volumetric concentration factor of 40. Our study provides a promising strategy for effective capture and recovery of GenX to enable its sustainable control and remediation.

Automated summary

This study introduces a highly porous amine-functionalized membrane for rapid capture of GenX and other anionic PFASs from contaminated water, with near-zero energy consumption. The membrane demonstrated high water permeability and efficient capture of pollutants, with a promising strategy for sustainable control and remediation.