Prediction of the Impact of Hydrochemistry on PFAS Removal Using Ion Exchange Resins

Ion exchange resins have emerged as an effective method for perfluoroalkyl and polyfluoroalkyl substances (PFAS) removal from contaminated water. However, their efficiency can vary depending on hydrochemical conditions and PFAS. This study investigates PFAS removal using the ion-exchange resin MIEXⓇ GOLD under a range of solution conditions and develops a predictive model to simulate the effects of salt type and concentration on PFAS removal for a wide range of ion exchange resins. Removal efficiency depends on PFAS head groups and chain length, with more hydrophobic PFAS exhibiting greater uptake by MIEXⓇ. Organic matter had a negligible impact on PFAS removal, while removal efficiency was impacted negatively by the presence of inorganic salts, suggesting competition for ion exchange sites between PFAS and salt anions. The model successfully simulated PFAS removal for a range of ion exchange resins, including when it was extended to predict PFAS removal across a wide range of water compositions (e.g., salts) and PFAS in cases when model parameters have not been measured. This research provides valuable insights into the effectiveness of ion exchange resins for PFAS removal, contributing to the optimization of water treatment processes.