title: Formation of mixed halogenated dibenzo-p-dioxins and dibenzofurans (PXDD/Fs).
abstract: This contribution investigates mechanistic and kinetic parameters pertinent to formation of mixed dibenzo-p-dioxins and dibenzofurans (PXDD/Fs) from the condensation reactions involving 2-chlorophenoxy (2-CPxy) and 2-bromophenoxy (2-BPxy) radicals. Keto-ether structures act as direct intermediates for the formation of DD, 1-MCDD, 1-MBDD, 1-B,6-CDD and 1-B,9-CDD molecules. Likewise, diketo adducts initiate the formation of 4-MCDF, 4-MBDF and 4-B,6-CDF compounds through interconversion and rearrangement reactions. As formation mechanisms of halogenated dibenzo-p-dioxins and dibenzofurans from precursors of brominated and chlorinated phenols are insensitive to substitution at meta and para sites, our mechanistic and kinetic analysis of reactions involving 2-BPxy and 2-CPxy should also apply to higher halogenated phenoxy radicals.
authors.affiliation: School of Engineering and Information Technology, Murdoch University, 90 South Street, Murdoch, WA 6150, Australia.
authors.forename: Anam
authors.initials: A
authors.lastname: Saeed
authors.affiliation: School of Engineering and Information Technology, Murdoch University, 90 South Street, Murdoch, WA 6150, Australia. Electronic address: M.Altarawneh@murdoch.edu.au.
authors.forename: Mohammednoor
authors.initials: M
authors.lastname: Altarawneh
authors.affiliation: School of Engineering and Information Technology, Murdoch University, 90 South Street, Murdoch, WA 6150, Australia.
authors.forename: Bogdan Z
authors.initials: BZ
authors.lastname: Dlugogorski
mesh_terms: D001572:Benzofurans / Q000737:chemistry*; D004147:Dioxins / Q000737:chemistry*; D004785:Environmental Pollutants / Q000737:chemistry*; D054879:Halogenation; D006846:Hydrocarbons, Halogenated / Q000737:chemistry*; D007700:Kinetics; D008956:Models, Chemical; D015394:Molecular Structure; D044367:Phase Transition; D010636:Phenols / Q000737:chemistry
chemical_list: D001572:Benzofurans; D004147:Dioxins; D004785:Environmental Pollutants; D006846:Hydrocarbons, Halogenated; D010636:Phenols; C042329:phenoxy radical; C023614:dibenzofuran; C020887:dibenzo(1,4)dioxin
keywords: Bromophenol; Chlorophenol; Polyhalogenated dibenzo-p-dioxins and dibenzofurans (PXDD/Fs); Reaction mechanism; Reaction rate constants