title: Rapid Selective Circumneutral Degradation of Phenolic Pollutants Using Peroxymonosulfate-Iodide Metal-Free Oxidation: Role of Iodine Atoms.
abstract: The development of environmentally friendly, oxidation-selective advanced oxidation processes (AOPs) for water decontamination is important for resource recovery, carbon dioxide abatement, and cost savings. In this study, we developed an innovative AOP using a combination of peroxymonosulfate (PMS) and iodide ions (I-) for the selective removal of phenolic pollutants from aqueous solutions. The results showed that nearly 100% degradation of phenol, bisphenol A, and hydroquinone was achieved after reaction for 4 min in the presence of 65 μM PMS and 50 μM I-. PMS-I-oxidation had a wide effective pH range, with the best performance achieved under circumneutral conditions. The ratio between [PMS] and [I-] influenced the degradation, and the optimal ratio was approximately 1.00 for the degradation of the phenols. Neither sulfate nor hydroxyl radicals were found to be the active species in PMS-I-oxidation. Instead, we found evidence that iodide atoms were the dominant oxidants. In addition, both Cl-and Br-also promoted the degradation of phenol in PMS solution. The results of this work may promote the application of reactive halogen species in water treatment.
authors.affiliation: Department of Civil Engineering, The University of Hong Kong , Pokfulam, Hong Kong.
authors.forename: Yong
authors.initials: Y
authors.lastname: Feng
authors.affiliation: Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University , Hung Hom, Hong Kong.
authors.forename: Po-Heng
authors.initials: PH
authors.lastname: Lee
authors.affiliation: State Key Laboratory of Pollution Control and Resources Reuse, School of Environmental Science & Engineering, Tongji University , Shanghai 200092, People's Republic of China.
authors.forename: Deli
authors.initials: D
authors.lastname: Wu
authors.affiliation: Department of Civil Engineering, The University of Hong Kong , Pokfulam, Hong Kong.
authors.forename: Kaimin
authors.identifier: 0000-0002-6461-3207
authors.initials: K
authors.lastname: Shih
mesh_terms: D007454:Iodides; D007455:Iodine; D008670:Metals; D010084:Oxidation-Reduction; D010545:Peroxides; D014874:Water Pollutants, Chemical
chemical_list: D007454:Iodides; D008670:Metals; D010545:Peroxides; D014874:Water Pollutants, Chemical; D007455:Iodine