The goal of this project is to advance the application of novel high-capacity sorbents for sustainable treatment of per- polyfluoroalkyl substances (PFAS) in waters impacted by aqueous film-forming foam (AFFF). Specific objectives include the following:

• Adaptation of novel sorbents to enable flow-through treatment of impacted water;
• Evaluation of their sorption capacity and kinetics in single compound and complex AFFF-containing matrices;
• Development of sustainable sorbent regeneration approaches; and
• Evaluation of long-term sorption and regeneration capacity in multi-cycle regeneration tests.

This work will have two key focus areas:

1. Improving sorption capacity of PFAS of interest, as well as PFAS precursors and the challenging-to-treat short-chain PFAS (e.g., perfluorobutanoic acid, perfluorobutanesulfonic acid) relative to standard granular activated carbon and ion exchange resins; and
2. Improving sustainable management of PFAS-containing sorptive media using safe and effective regeneration approaches. Media regeneration approaches will consider design and operation characteristics of follow-on destructive treatment of concentrated PFAS (e.g., plasma, sonolysis, electrochemical treatment).

Three novel sorbent types will be prepared, characterized, and comparatively evaluated for their capacity to remove PFAS from water, and to be regenerated for their reuse. Sorbents include lanthanide-based, metal-organic framework-based, and reduced graphene oxide-supported nanoscale zero valent iron-based media. Preliminary evaluations demonstrate significantly higher sorption capacity relative to standard activated carbon and ion exchange resins, and they are effective over a broad range of PFAS chain lengths. This research focuses on optimizing the sorbents’ PFAS removal, conducting a thorough characterization of PFAS sorption capacity and kinetics in batch and flow-through systems, and optimizing regeneration approaches to remove PFAS from sorptive media, enabling reuse of the media and ultimate destruction of PFAS. Finally, life cycle costs and benefits of the three media will be compared alongside those of activated carbon and ion exchange resins.

The goal of this work is to identify at least one combination of sorptive media and regeneration approach that offers improved sorption over activated carbon and ion exchange resins for a broader suite of PFAS at lower cost and with lower life cycle impacts. More selective and higher capacity regenerable sorbents will decrease costs associated with treatment of PFAS-impacted water. Sorptive media can be used in a range of contexts for PFAS treatment in situ or ex situ – independently or as part of a treatment train. Additionally, because PFAS can be readily disassociated from these regenerable sorbents, the PFAS separated by and concentrated onto the sorbents can be removed using a limited volume and destroyed by a follow-on destructive treatment technology, offering a permanent solution. (Anticipated Project Completion - 2025)