Poly- and perfluoroalkyl substances destruction via advanced reduction processes: assessing scientific and commercial progress and prospects

Abstract

Advanced reduction processes (ARPs) have demonstrated efficient degradation of poly- and perfluoroalkyl substances (PFAS). This paper describes the maturity level of more established ultraviolet (UV)-based ARPs, along with other reductive processes in the research stage. Commercial ARP vendors offer varying formats of UV-activated photosensitization of chemical additives to generate hydrated electrons in batch mode. These systems are typically coupled with preliminary separation processes and treat a concentrated PFAS waste stream. Other reduction approaches such as metal catalytic reduction have not yet left the academic space. Key areas of progress needed include cost-effective pretreatment approaches, and, relatedly, demonstration of ARPs in complex waste concentrates. Further improvement in reaction kinetics and developing an effective process for treating the most recalcitrant PFAS will also increase adoption of ARPs.