Fluoropolymer sorbent for efficient and selective capturing of per- and polyfluorinated compounds

Abstract Per- and poly-fluoroalkyl substances (PFAS) represent a group of compounds, such as perfluorooctanoic acid (PFOA) and perfluorooctylsulfonic acid (PFOS), that have raised environment and human health concerns. Opportunities exist for improved efficiency and scalable technologies over more broad-spectrum approaches for capture and utilization of these compounds from contaminated sources. In this study, we introduce a new type of reusable polymeric sorbent (perfluoropolyether-containing resin (PFPE-IEX+)) for rapid, efficient, and selective removal of multiple PFAS impurities from various contaminated water sources. The sorbent contains a hydrophobic polystyrenic backbone, with positively charged quaternary ammonium functional group and PFPE segments being crosslinked by divinylbenzene. The PFPE-IEX + resin shows superior PFAS sorption efficiency compared with commercially available sorbents in real PFAS contaminated media. The resin achieves > 98% removal efficiency and > 500 mg/g sorption capacity for all types of examined PFAS, including the short-chain heptafluorobutyric acid (PFBA) and hexafluoropropylene oxide dimer acid (HFPO-DA). We dedicated efforts to achieve efficient PFAS removal without breakthrough and subsequent resin regeneration with ~ 100% PFAS recovery in a proof-of-concept cartridge setup using real PFAS contaminated water sources, including potable water and landfill leachate. The recycled PFAS was then used as electrolyte additives to facilitate the formation of a ZnF2 rich protection layer on the anode surface to improve the cycling stability of aqueous zinc batteries. The outcomes of this study not only offer valuable guidance to the design and preparation of efficient sorbents applicable in cartridge-based PFAS removal from the environment, but also present an important strategy to reuse the recycled PFAS in battery systems to turn an environmental concern to a societal benefit to wealth.