Membrane-based technologies for per- and poly-fluoroalkyl substances (PFASs) removal from water: Removal mechanisms, applications, challenges and perspectives

Abstract

Water purification from per- and poly-fluoroalkyl substances (PFASs), as a group of persistent and mobile fluoro-organic contaminants, is receiving increasing attention worldwide due to the ubiquitous presence of these highly toxic compounds. To reduce the risk of exposure of human life to PFASs and their dispersion in the environment, various techniques, primarily based on membrane technologies, have been rapidly developed. Here we critically review and analyze the current state-of-the-art of membrane-based techniques for PFASs removal, including direct membrane filtrations, adsorption-based membranes, and hybrid membrane processes. Membranes performance, treatment efficiencies, characteristic parameters and mechanisms for PFASs removal are discussed in detail. We highlight and discuss advantages and limitations, as well as challenges and prospects of individual membrane-based PFASs treatments, pointing towards the practical and sustainable application of these technologies.

Keywords: Adsorption membrane; Hybrid membrane processes; Mechanisms; Nanofiltration; PFASs; Reverse osmosis.