Removal of persistent organic pollutants (POPs) from waters and wastewaters by the use of ionizing radiation

The most important advantages of the use of ionizing radiation over other AOPs are exceptionally efficient in situ generation of very reactive oxidizing free radicals OH from water radiolysis and very unique simultaneous generation of strongly reducing hydrated electrons. They allow to carry out Advanced Oxidation and Reduction Processes (AO/RPs) simultaneously. Carrying out only oxidative or reductive processes is also possible by the use of appropriate scavengers of free radicals in irradiated solutions. For the application of these processes for environmental protection purposes gamma-rays from radioisotope sources or beams of accelerated electrons are most commonly used. In the case of particularly resistant POPs some chemical additives to the irradiated solutions may enhance the yield of decomposition. This review based on 125 references reported so far presents the applications of the discussed technology in removing POPs from waters and wastewaters, including pesticides listed among POPs, dioxins, polychlorinated biphenyls, polycyclic aromatic hydrocarbons and selected perfluorinated surfactants