title: Abatement of Polychoro-1,3-butadienes in Aqueous Solution by Ozone, UV Photolysis, and Advanced Oxidation Processes (O3/H2O2and UV/H2O2).
abstract: The abatement of 9 polychloro-1,3-butadienes (CBDs) in aqueous solution by ozone, UV-C(254 nm) photolysis, and the corresponding advanced oxidation processes (AOPs) (i.e., O3/H2O2and UV/H2O2) was investigated. The following parameters were determined for 9 CBDs: second-order rate constants for the reactions of CBDs with ozone (kO3) (<0.1-7.9 × 103M-1s-1) or with hydroxyl radicals (k•OH) (0.9 × 109- 6.5 × 109M-1s-1), photon fluence-based rate constants (k') (210-2730 m2einstein-1), and quantum yields (Φ) (0.03-0.95 mol einstein-1). During ozonation of CBDs in a natural groundwater, appreciable abatements (>50% at specific ozone doses of 0.5 gO3/gDOC to ∼100% at ≥1.0 gO3/gDOC) were achieved for tetra-CBDs followed by (Z)-1,1,2,3,4-penta-CBD and hexa-CBD. This is consistent with the magnitude of the determined kO3and k•OH. The formation of bromate, a potentially carcinogenic ozonation byproduct, could be significantly reduced by addition of H2O2. For a typical UV disinfection dose (400 J/m2), various extents of phototransformations (10-90%) could be achieved. However, the efficient formation of photoisomers from CBDs with E/Z configuration must be taken into account because of their potential residual toxicity. Under UV-C(254 nm) photolysis conditions, no significant effect of H2O2addition on CBDs abatement was observed due to an efficient direct phototransformation of CBDs.
authors.affiliation: School of Architecture, Civil and Environmental Engineering (ENAC), École Polytechnique Fédérale de Lausanne (EPFL) , 1015 Lausanne, Switzerland.
authors.forename: Minju
authors.identifier: 0000-0001-9115-1274
authors.initials: M
authors.lastname: Lee
authors.affiliation: Eawag, Swiss Federal Institute of Aquatic Science and Technology , Ueberlandstrasse 133, 8600 Dübendorf, Switzerland.
authors.forename: Tony
authors.identifier: 0000-0002-3051-6249
authors.initials: T
authors.lastname: Merle
authors.affiliation: EMPA, Swiss Federal Laboratories for Materials Science and Technology , 8600 Dübendorf, Switzerland.
authors.forename: Daniel
authors.identifier: 0000-0002-9335-9527
authors.initials: D
authors.lastname: Rentsch
authors.affiliation: Eawag, Swiss Federal Institute of Aquatic Science and Technology , Ueberlandstrasse 133, 8600 Dübendorf, Switzerland.
authors.forename: Silvio
authors.identifier: 0000-0001-6848-947X
authors.initials: S
authors.lastname: Canonica
authors.affiliation: School of Architecture, Civil and Environmental Engineering (ENAC), École Polytechnique Fédérale de Lausanne (EPFL) , 1015 Lausanne, Switzerland.|Eawag, Swiss Federal Institute of Aquatic Science and Technology , Ueberlandstrasse 133, 8600 Dübendorf, Switzerland.
authors.forename: Urs
authors.initials: U
authors.lastname: von Gunten
mesh_terms: D006861:Hydrogen Peroxide; D010084:Oxidation-Reduction; D010126:Ozone; D010782:Photolysis; D014466:Ultraviolet Rays; D018508:Water Purification
chemical_list: D010126:Ozone; D006861:Hydrogen Peroxide