Challenging the contamination of per- and polyfluoroalkyl substances in water: advanced oxidation or reduction?

Aerobic Biotransformation and Defluorination of Fluoroalkylether Substances (ether PFAS): Substrate Specificity, Pathways, and Applications

“…Up to28% increase in the total defluorination could be achieved by aerobic biological post-treatment, where many chemical treatment products with a -CH 2 - moiety were further biodegraded and defluorinated into short-chain perfluorinated acids. Compared to advanced oxidation processes (AOPs), which would result in the same short-chain perfluorinated end products, , the biological post-treatment is more cost-effective, particularly when there is high-level nonfluorinated dissolved organic carbon in the matrix that may severely affect the AOP performance. After the aerobic biological post-treatment, although the defluorination of GenX was still incomplete, it simplified the major end products to three short-chain PFCAs (i.e., PFPrA, 2,3,3,3-tetrafluoropropionic acid, and TFA), which could be further degraded by a secondary advanced reduction treatment. − TFA can be quickly and completely degraded by UV/sulfite treatment, while PFPrA and 2,3,3,3-tetrafluoropropionic acid may form the chemically stable trifluoropropionate, which can be completely destroyed in another round of aerobic biological post-treatment .…”

Effect of chain length, electrolyte composition and aerosolization on the removal of per- and polyfluoroalkyl substances during electrochemical oxidation

“…are currently being investigated and optimized. 1,4,[16][17][18][19] The aim of these technologies is to break down the PFAS molecules into less toxic, more manageable by-products.…”

Enhanced coagulation coupled with cyclic IX adsorption–ARP regeneration for removal of PFOA in drinking water treatment

“…ARPs involve a chemical degradation process that produces sufficient and highly reducing radicals capable of destroying contaminants in water (Cui et al, 2020). During the ARP treatment, the effective degradation of PFAS in water is principally attributed to the formation of hydrated electrons (e aq − ) (Amador et al, 2023; Bentel et al, 2019; Chen et al, 2022; Cui et al, 2020; Fennell, Mezyk, & McKay, 2022; Fennell, Odorisio, & McKay, 2022; Maza et al, 2023; Sun et al, 2018). As excess and solvated electrons, e aq − can be generated in electrically neutral water through multiple pathways such as direct pulse radiolysis, ionizing radiation, and photo‐detachment of certain solutes (e.g., sulfite [SO 3 2− ]) (Devonshire & Weiss, 1968; Herbert & Coons, 2017; Larsen et al, 2010).…”