The ultimate goal for treatment of per- and polyfluoroalkyl substances (PFASs) is to both remove and destroy the chemicals. Achieving the goal of removal remains poorly defined, but most experts agree that it will require meeting stringent standards (e.g., low ng/L concentration) for not only commonly mentioned PFASs like PFOS and PFOA, but the class of chemicals as a whole. Removal can be achieved by a variety of adsorption and membrane separations technologies, with granular activated carbon (GAC) adsorption, anion exchange resins (AER) being the only technologies currently adopted at full scale. A range of other adsorbents, membrane processes, and innovative foam fractionation processes are also being studied. Each process has distinct advantages and disadvantages, achieve varying levels of PFAS concentration, and concentrate PFAS to varying degrees within residual byproduct streams. Researchers  have also been investigating the effectiveness of different destructive treatment technologies for PFAS-contaminated water. This is challenging due to the recalcitrant nature of PFASs. To date, the most effective approaches include thermochemical, electrocatalytic, and photochemical and plasma-based technologies. Published reports indicate varying levels of success, but collectively results show energy requirements that exceed the most costly water treatment processes (e.g., seawater desalination). As a result, none have been adopted as a primary treatment technology at full scale. A more promising strategy involves coupling separations processes (to achieve treatment goals while simultaneously concentrating the PFAS contaminants into smaller volumes) with destructive treatment of the resulting byproduct streams. This presentation will summarize the state of the science and compare alternatives for both (1) separation/concentration of PFASs, and (2) destructive treatment of PFAS-contaminated concentrate streams, using work from recent laboratory and pilot studies as examples. Research needs and opportunities will also be discussed.

Developing and evaluating hybrid concentration-destruction treatment trains for water contaminated with per- and polyfluoroalkyl substances (PFASs)

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.