title: Activation of persulfate by irradiated magnetite: implications for the degradation of phenol under heterogeneous photo-Fenton-like conditions.
abstract: We show that phenol can be effectively degraded by magnetite in the presence of persulfate (S2O8(2–)) under UVA irradiation. The process involves the radical SO4(–•), formed from S2O8(2–) in the presence of Fe(II). Although magnetite naturally contains Fe(II), the air-exposed oxide surface is fully oxidized to Fe(III) and irradiation is required to produce Fe(II). The magnetite + S2O8(2–) system was superior to the corresponding magnetite + H2O2 one in the presence of radical scavengers and in a natural water matrix, but it induced phenol mineralization in ultrapure water to a lesser extent. The leaching of Fe from the oxide surface was very limited, and much below the wastewater discharge limits. The reasonable performance of the magnetite/persulfate system in a natural water matrix and the low levels of dissolved Fe are potentially important for the removal of organic contaminants in wastewater.
authors.forename: Paola
authors.initials: P
authors.lastname: Avetta
authors.forename: Alessia
authors.initials: A
authors.lastname: Pensato
authors.forename: Marco
authors.initials: M
authors.lastname: Minella
authors.forename: Mery
authors.initials: M
authors.lastname: Malandrino
authors.forename: Valter
authors.initials: V
authors.lastname: Maurino
authors.forename: Claudio
authors.initials: C
authors.lastname: Minero
authors.forename: Khalil
authors.initials: K
authors.lastname: Hanna
authors.forename: Davide
authors.initials: D
authors.lastname: Vione
mesh_terms: D019840:2-Propanol / Q000737:chemistry; D002244:Carbon / Q000737:chemistry; D005290:Ferric Compounds / Q000737:chemistry; D052203:Ferrosoferric Oxide / Q000032:analysis*; D005296:Ferrous Compounds / Q000737:chemistry; D006861:Hydrogen Peroxide / Q000737:chemistry; D017665:Hydroxyl Radical; D007501:Iron / Q000737:chemistry; D009930:Organic Chemicals / Q000737:chemistry; D010084:Oxidation-Reduction; D019800:Phenol / Q000737:chemistry*; D013431:Sulfates / Q000032:analysis*; D014867:Water / Q000737:chemistry
chemical_list: C045076:Fenton's reagent; D005290:Ferric Compounds; D005296:Ferrous Compounds; D009930:Organic Chemicals; D013431:Sulfates; D014867:Water; D017665:Hydroxyl Radical; D019800:Phenol; D002244:Carbon; D006861:Hydrogen Peroxide; D007501:Iron; D019840:2-Propanol; D052203:Ferrosoferric Oxide