Per- and polyfluoroalkyl substances (PFAS) were first developed in the 1940s and have since been used for a broad range of uses in consumer and industrial products. Their tendency to bioaccumulate in water causes negative environmental and health impacts, necessitating worldwide PFAS monitoring and remediation efforts. While traditional sorbent materials, such as activated carbon and ion exchange resins, are being used to remove PFAS from municipal drinking water, the materials are not easily regenerated in situ. Zeolites have been identified as effective and selective sorbent materials for PFAS, and they have the potential to be regenerated on location. Zeolites have a wide range of pore openings and tunable properties, making them ideal for removing both short- and long-chain PFAS from the environment. Furthermore, the ion exchange of zeolites can increase their own catalytic or adsorptive capability. In this presentation, experimental data for calcium exchanged zeolite CP814E is discussed. Adsorption properties change with varying calcium loadings, with the adsorption of PFAS increasing after ion exchange from the hydrogen form. The highest calcium loadings showed 2-5 fold increases in adsorption for PFCAs but were not as high for PFASs. From single adsorption isotherms, the best performing Ca-Beta was tested in real water samples, resulting in high adsorption of long-chain PFAS, with lower adsorption of short-chain PFAS. Thermal and solvent regeneration of these zeolites was also tested and findings demonstrated ability to recover adsorptive capacity.
