title: Abatement of the inhibitory effect of chloride anions on the photo-Fenton process.
abstract: The inhibition of the photo-Fenton (Fe2+/Fe3+, H2O2, UV light) degradation of synthetic phenol wastewater solutions by chloride ions is shown to affect primarily the photochemical step of the process, having only a slight effect on the thermal or Fenton step. Kinetic studies of the reactions of oxoiron (IV) (FeO2+) with phenol indicate that, if FeO2+ is formed in the photo-Fenton degradation, its role is probably minor. Finally, it is shown that, for both a synthetic phenol wastewater and an aqueous extract of Brazilian gasoline, the inhibition of the photo-Fenton degradation of the organic material in the presence of chloride ion can be circumvented by maintaining the pH of the medium at or slightly above 3 throughout the process, even in the presence of significant amounts of added chloride ion (0.5 M).
authors.affiliation: Instituto de Química, Universidade de São Paulo, CP 26077, São Paulo 05513-970, Brazil.
authors.forename: Amilcar Júnior
authors.initials: AJ
authors.lastname: Machulek
authors.forename: José E F
authors.initials: JE
authors.lastname: Moraes
authors.forename: Carolina
authors.initials: C
authors.lastname: Vautier-Giongo
authors.forename: Cristina A
authors.initials: CA
authors.lastname: Silverio
authors.forename: Leidi C
authors.initials: LC
authors.lastname: Friedrich
authors.forename: Cláudio A O
authors.initials: CA
authors.lastname: Nascimento
authors.forename: Monica C
authors.initials: MC
authors.lastname: Gonzalez
authors.forename: Frank H
authors.initials: FH
authors.lastname: Quina
mesh_terms: D000838:Anions; D002384:Catalysis; D002712:Chlorides / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D010777:Photochemistry
chemical_list: D000838:Anions; D002712:Chlorides