Silicate-Enabled Mechanochemical Mineralization of Polymeric and Nonpolymeric PFAS into Sodium Fluoride

Per- and polyfluoroalkyl substances (PFAS) are persistent environmental pollutants, some associated with detrimental impacts on human health upon chronic exposure. Many processes have been reported to destroy PFAS, although high-temperature thermal methods such as incineration or pyrolysis are still the most commonly used for bulk waste. Herein, we report a highly effective mechanochemical process designed to destroy polymeric and nonpolymeric PFAS with recovery of fluorine as NaF, a salt endorsed by international organizations for public oral health. The process consists of ball milling PFAS with commercially available sodium silicate, an inexpensive and easy-to-handle reagent found to be superior to sodium phosphate or carbonate. This approach represents a promising step toward remediating the global PFAS crisis with a circular fluorine economy in mind.