Desorption from PFAS-Contaminated Zeolite

Per- and polyfluoroalkyl substances (PFAS), or "forever chemicals," are persistent man-made chemicals in the environment. Their negative health effects and widespread water contamination have led to their regulation in public drinking water treatment facilities. While activated carbon is common for PFAS removal, its limited effectiveness, end-of-life issues, and economic inefficiencies necessitate research into alternative materials. Zeolites, a type of molecular sieve, with their microporous structure, have proven to adsorb a wide range of PFAS. Though more expensive than activated carbon, zeolites can be integrated into existing processes and are more easily regenerable. This reduces the long-term demand for materials, disposal costs, and environmental concerns associated with end-of-life. Supercritical carbon dioxide is being explored as an effective and "green" solvent for zeolite regeneration. Ongoing research focuses on its ability to remove various PFAS from zeolite CP814E*, with NSF (National Sanitation Foundation)-approved additives such as acetic acid and ammonium hydroxide also being evaluated. PFAS quantification is performed using LC-MS/MS analysis. If successful, future work will involve scaling up designs and life cycle comparisons with other regeneration methods.