Methods and systems of PFAS destruction including recovery and recycling of reactants. The method may include combining water including PFAS with fresh reactants including photosensitizer, sulfite salt and base to form an initial treatment solution having a pH of about 10 or more, irradiating the initial treatment solution with UV light in a photoreactor to destroy a portion of the PFAS and form treatment effluent, passing the treatment effluent through an ion selective membrane, combining the reject solution with water including PFAS to form a subsequent treatment solution, irradiating the subsequent treatment solution with UV light in the photoreactor to destroy a portion of the PFAS and form a treatment effluent, and repeating the process to recycle the recovered reactants one or more additional times. After the recovered reactants are recycled multiple times, they may be purged.

The present disclosure includes systems, devices, and methods for a reactor, such as a sonication reactor, for destruction of Per- and polyfluoroalkyl substances (PFASs). In one aspect of the disclosure, the reactor includes a housing having a base and one or more walls that cooperate to define a chamber and a transducer disposed the chamber. The transducer is configured to generate a plurality of sound waves such that when PFAS solution is disposed within the chamber, the sound waves propagate through the liquid and at least some of the one or more PFAS compounds are pyrolyzed or otherwise degraded. Other aspects and features are also claimed and described.

A method for removing PFAS from a PFAS-containing aqueous phase, comprising adding to said aqueous phase a surfactant composition comprising at least one cationic surfactant, to allow the surfactant to form micelles in said aqueous phase, and bringing said micelle-containing aqueous phase in contact with an ultrafiltration membrane under pressure, to obtain a permeate flow aqueous phase having a reduced concentration of PFAS.

A decontamination method for subsurface aquifers having per- and polyfluoroalkyl substances (PFAS) contaminants by injecting gas through a screened well or open tube through a porous media to form buoyant material where the PFAS contaminants accumulate on and/or in the buoyant material and rise to the water table or top of the aquifer with PFAS that desorbs from the buoyant material and concentrates in the shallow groundwater, and extracting or sequestering the groundwater near the water table or top of the confined aquifer and/or collecting the buoyant material for treatment. The method may include treatment of aquifer material consisting of gravel, sand, silt, clay, or fractured geologic media, or combination, and extraction through phytoremediation, groundwater extraction wells, wellpoint systems, or groundwater extraction trenches and include a seal and/or check valve near the water table in the trench to selectively permit water and buoyant material to flow upward.

Processes and apparatuses for degrading PFAS into calcium fluoride, carbon dioxide, and water. PFAS are heated and introduced to a calcium base which will degrade the PFAS. The PFAS may be in a stream that is a PFAS enriched stream formed by desorbing the PFAS from an adsorbent which removed the PFAS from a contaminant stream. The PFAS may be desorbed in the presence of the calcium base. The calcium base may be calcium hydroxide, calcium oxide, calcium carbonate, or combinations thereof.