Efficient adsorptive removal of short-chain perfluoroalkyl acids using reed straw-derived biochar (RESCA)

Drinking water and groundwater treatment of perfluoroalkyl acids (PFAAs) heavily relies on adsorption-based approaches using carbonaceous materials, such as granular activated carbon (GAC). Application GAC is restricted by its inefficiency to remove short-chain PFAAs that have prevalently emerged substitutes and/or metabolites long-chain polyfluoroalkyl substances (PFAS). Here, we synthesized reed straw-derived biochar (RESCA) exhibiting exceptional removal efficiencies (>92%) toward at environment-relevant concentrations (e.g., 1 ?g/L). Pseudo-second-order kinetic constants RESCA were 1.13 1.23 L/(mg h) for perfluorobutanoic acid (PFBA) perfluorobutanesulfonic (PFBS), respectively, over six times greater than GAC. SEM imaging BET analysis revealed the combination highly hydrophobic surface scattered distribution mesopores (2–10 nm in diameter) was associated with rapid adsorption PFAAs. RESCA-packed filters demonstrated effective mixture three influent flow rate up 45 mL/min. In contrast, GAC-packed significantly less efficient PFAAs, which also negatively affected increase rate. Efficacy validated four PFAA-spiked samples from different sites. Dissolved organic matter (DOC) >8 mg/L can affect RESCA. Feasibility scaling system investigated breakthrough simulation. Overall, represents a green adsorbent alternative feasible scalable wide spectrum chain lengths functional moieties.