Water and Remediation Catalog.

Authors: Bahareh Tajdini, Hooman Vatankhah, Ethan R. Pezoulas, Chuhui Zhang, Christopher P Higgins, Christopher Bellona

DOI: https://doi.org/10.1016/j.watres.2024.122774

Synopsis:

• A comparative RSSCT study on AFFF-contaminated groundwater investigating efficacy of commercial adsorbent: GAC, surface modified clay (SMC), and anionic exchange resin (AER) for treatment of cationic, zwitterionic, and anionic PFAS, expanding beyond the typical 40 PFAS monitored in the USEPA Methods
• SMC was found to perform similarly to AER regarding cationic, zwitterionic, and anionic PFAS, where linear sulfonate PFAS were found to have the highest affinity for SMC’s. Both sorbents were found to have negligible removal of net (+) PFAS due to primarily ionic interactions with SMC and AER.
• SMC sorbents regularly outperformed GAC for anionic PFAS removal, including ultra short chain iterations
• Recommendation from Author: in AFFF-impacted waters, a combination system of GAC and SMC would be a strong strategy to sequester all three categories of PFAS, cationic, zwitterionic, and anionic, at all relevant chain lengths

Brief: This new publication on surface modified clay (SMC) adsorbent displayed comparable adsorption behavior to anion exchange resins in AFFF-impacted groundwater samples through RSSCT analyses, with favorable sorbtion to anionic and net negative PFAS. Based on these results, a system with tandem GAC and SMC could be a strong candidate to ensure removal of a wide range of PFAS beyond the USEPA 40.