Use of materials containing zerovalent iron nanoparticles for PFAS removal from water. A critical review

Abstract

Per- and polyfluoroalkyl substances (PFAS) are a large, complex group of synthetic chemicals widely used in consumer products around the world since the ‘50s. PFAS molecules have a chain of linked carbon and fluorine atoms and, due to the very strong C—F bonds, these chemicals do not degrade easily in the environment, are environmentally persistent and people and animals are exposed to them with multiple health effects. For these reasons, these “forever chemicals” have been declared priority pollutants. Several technologies such as adsorption, ion exchange, coagulation, sand filtration, nanofiltration, reverse osmosis, biological treatments and advanced oxidation/reduction processes have been tested to remove these very persistent and dangerous pollutants from water, with different results. Nanotechnology for water treatment is a convenient way of removing pollutants, especially through the use of nanosized iron particles. This review focuses on the possible use of zerovalent iron nanoparticles for removal of PFAS in water. As main conclusions, systems must be anaerobic and bare nanoparticles should be modified for their use in the PFAS treatment to promote a good removal.