Ex Situ Treatment of PFAS-Impacted Groundwater Using Ion Exchange with Regeneration

APTIM Authors/Contributors

Abstract

This project aimed to develop treatment trains for PFAS-contaminated groundwater consisting of ion exchange (IX) using novel resins coupled with sonochemical destruction of PFAS in waste regeneration brine. While the project focused on ion exchange to remove PFOA and PFOS, it also examined the treatment of the broader range of PFAS (shorter- and longer-chain perfluoroalkyl acids and sulfonates) and precursors (fluorotelomer sulfonates). The technical approach consisted of lab experiments to identify and test new IX resins combined with a small-scale field study to demonstrate their effectiveness in removing a broad range of PFAS from groundwater, relative to granular activated carbon. Sonochemical destruction of PFAS in anion exchange regeneration wastes and the potential factors that could impact PFAS destruction were also examined. An Excel-based tool was also developed to guide which media or combination of media would be cost-effective for PFAS removal under various conditions. The main benefits were (1) the development and validation of efficient IX resins and resin systems for removing a broad range of PFAS and precursor compounds from groundwater; (2) the development and testing of resin regeneration waste treatment approaches to destroy accumulated PFAS and precursors in regenerant waste; (3) field pilot testing the treatment train, and; (4) preparing a tool that provides technical and cost guidance for IX resin or GAC treatment based on a given site’s PFAS contamination profile and groundwater chemistry.

• Executive Summary
• Guidance 
• Final Report