title: Comparative study of the destruction of polychlorinated dibenzo-p-dioxins and dibenzofurans during Fenton and electrochemical oxidation of landfill leachates.
abstract: Two advanced oxidation processes (AOPs) that provide a broad-spectrum contaminant destruction option were applied to the treatment of the leachates, namely electrochemical and Fenton oxidation. Despite the similar efficiency in the oxidation of major organic contaminants, approximately 90% reduction of chemical oxygen demand after 180 min, our results showed a different behaviour of both AOPs in the oxidation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). A concentration reduction of 73% for 1,2,3,4,6,7,8-HpCDD and of 71% for OCDD was reached after 180 min of electrochemical oxidation and the total toxic equivalent of the sample was reduced in 58%. However, Fenton oxidation followed a different trend and for similar operation times, it was detected an increase in the concentration of several PCDD/Fs congeners, specially stressed for the major congeners 1,2,3,4,6,7,8-HpCDD, OCDD and OCDF, and in the total toxicity of the sample between 12.5% and 128%. Comparison of the results and the rationale behind their difference are finally discussed.
authors.affiliation: Dpto. Ingeniería Química y Q.I. ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Vallejo
authors.forename: M F
authors.initials: MF
authors.lastname: San Román
authors.forename: A
authors.initials: A
authors.lastname: Irabien
authors.forename: I
authors.initials: I
authors.lastname: Ortiz
mesh_terms: D001572:Benzofurans / Q000032:analysis / Q000737:chemistry*; D000072338:Dibenzofurans, Polychlorinated; D055664:Electrochemical Techniques; D006861:Hydrogen Peroxide / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D000072317:Polychlorinated Dibenzodioxins / Q000031:analogs & derivatives* / Q000032:analysis / Q000737:chemistry; D012037:Refuse Disposal / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry*
chemical_list: D001572:Benzofurans; D000072338:Dibenzofurans, Polychlorinated; C045076:Fenton's reagent; D000072317:Polychlorinated Dibenzodioxins; D014874:Water Pollutants, Chemical; D006861:Hydrogen Peroxide; D007501:Iron