Effective removal of per- and polyfluoroalkyl substances (PFAS) from the environment has become a major focus of a number of research groups due to their high stability and persistence in the environment. In this study, we report a fundamental study of the removal of one of the most extensively produced PFAS, perfluorooctanoic acid (PFOA), using amphiphilic perfluoropolyether (PFPE)-containing block copolymers as effective sorbents. The results demonstrate interactions between PFOA and the PFPE blocks and that the extent of sorption is higher for the block copolymer with the shorter poly­(oligo­(ethylene glycol)­methyl ether acrylate) segments. High selectivity of sorption was further confirmed by the addition of 10% (v/v) fetal bovine serum to phosphate-buffered saline. The presence of dissolved proteins and other biomolecules did not interfere with the removal of PFOA from solution. Overall, the results provide important design parameters and a potential platform for preparing efficient sorbents for treating PFAS samples at environmentally relevant concentrations.

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The co-occurrence of various chemical and biological contaminants of emerging concerns has hindered the application of water recycling. This study aims to develop a heterogeneous photo-Fenton treatment by fabricating nano pyrite (FeS2) on graphene oxide (FeS2@GO) to simultaneously remove antibiotic resistant bacteria (ARB), antibiotic resistance genes (ARGs), and micropollutants (MPs). A facile and solvothermal process was used to synthesize new pyrite-based composites. The GO coated layer forms a strong chemical bond with nano pyrite, which enables to prevent the oxidation and photocorrosion of pyrite and promote the transfer of charge carriers. Low reagent doses of FeS2@GO catalyst (0.25 mg/L) and H2O2 (1.0 mM) were found to be efficient for removing 6-log of ARB and 7-log of extracellular ARG (e-ARG) after 30 and 7.5 min treatment, respectively, in synthetic wastewater. Bacterial regrowth was not observed even after a two-day incubation. Moreover, four recalcitrant MPs (sulfamethoxazole, carbamazepine, diclofenac, and mecoprop at an environmentally relevant concentration of 10 μg/L each) were completely removed after 10 min of treatment. The stable and recyclable composite generated more reactive species, including hydroxyl radicals (HO•), superoxide radicals (O2 • –), singlet oxygen (1O2). These findings highlight that the synthesized FeS2@GO catalyst is a promising heterogeneous photo-Fenton catalyst for the removal of emerging contaminants.

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