title: Oxidizing capacity of periodate activated with iron-based bimetallic nanoparticles.
abstract: Nanosized zerovalent iron (nFe0) loaded with a secondary metal such as Ni or Cu on its surface was demonstrated to effectively activate periodate (IO4-) and degrade selected organic compounds at neutral pH. The degradation was accompanied by a stoichiometric conversion of IO4- to iodate (IO3-). nFe0 without bimetallic loading led to similar IO4- reduction but no organic degradation, suggesting the production of reactive iodine intermediate only when IO4- is activated by bimetallic nFe0 (e.g., nFe0-Ni and nFe0-Cu). The organic degradation kinetics in the nFe0-Ni(or Cu)/IO4- system was substrate dependent: 4-chlorophenol, phenol, and bisphenol A were effectively degraded, whereas little or no degradation was observed with benzoic acid, carbamazepine, and 2,4,6-trichlorophenol. The substrate specificity, further confirmed by little kinetic inhibition with background organic matter, implies the selective nature of oxidant in the nFe0-Ni(or Cu)/IO4- system. The comparison with the photoactivated IO4- system, in which iodyl radical (IO3•) is a predominant oxidant in the presence of methanol, suggests IO3• also as primary oxidant in the nFe0-Ni(or Cu)/IO4- system.
authors.affiliation: Center for Water Resource Cycle, Korea Institute of Science and Technology , Seoul 136-791, Korea.
authors.forename: Hongshin
authors.initials: H
authors.lastname: Lee
authors.forename: Ha-Young
authors.initials: HY
authors.lastname: Yoo
authors.forename: Jihyun
authors.initials: J
authors.lastname: Choi
authors.forename: In-Hyun
authors.initials: IH
authors.lastname: Nam
authors.forename: Sanghyup
authors.initials: S
authors.lastname: Lee
authors.forename: Seunghak
authors.initials: S
authors.lastname: Lee
authors.forename: Jae-Hong
authors.initials: JH
authors.lastname: Kim
authors.forename: Changha
authors.initials: C
authors.lastname: Lee
authors.forename: Jaesang
authors.initials: J
authors.lastname: Lee
mesh_terms: D002733:Chlorophenols / Q000737:chemistry; D004777:Environment; D006863:Hydrogen-Ion Concentration; D007501:Iron / Q000737:chemistry*; D007700:Kinetics; D008027:Light; D053758:Nanoparticles / Q000737:chemistry*; D016877:Oxidants / Q000737:chemistry; D010084:Oxidation-Reduction; D010316:Particle Size; D010504:Periodic Acid / Q000737:chemistry*
chemical_list: D002733:Chlorophenols; D016877:Oxidants; D010504:Periodic Acid; C029107:4-chlorophenol; C009288:metaperiodate; D007501:Iron