Insight into electro-Fenton and photo-Fenton for the degradation of antibiotics: Mechanism study and research gaps

With the development of the degradation of persistent organic pollutants in the wastewater, antibiotics have been considered as emerging pollutants. Their lasting effects on the entire ecosystems directly resulted in irreversible damage all over the world. Electro-Fenton, photo-Fenton, photoelectro-Fenton and solar photoelectro-Fenton processes have been adopted to the elimination of antibiotics for the considerable efficiency. The mechanism, advantage, disadvantage, and the impacts of key parameters for each method are discussed based on the recent works, respectively. The cost aspects of electro-Fenton and photo-Fenton are analyzed for practical application. The degradation pathway as well as the toxicity evaluation of the antibiotics is reviewed. Finally, research needs and unfilled gaps have been proposed, including blocks from unpredicted impurities, pilot-scale study for the remediation of polluted water, pretreatment of antibiotic effluent, cognition of high-performance electrode, and characterization of intermediates. All of them suggested that electro-Fenton and photo-Fenton could be adopted as an ecological and efficiency ways for the elimination of antibiotics.