title: Oxidation of flame retardant tetrabromobisphenol a by aqueous permanganate: reaction kinetics, brominated products, and pathways.
abstract: In this work, the most widely used brominated flame retardant tetrabromobisphenol A (TBrBPA) was shown to exhibit appreciable reactivity toward potassium permanganate [Mn(VII)] in water over a wide pH range of 5-10 with the maxima of second-order rate constants (kMn(VII) = 15-700 M(-1) s(-1)) at pH near its pKa values (7.5/8.5). A novel precursor ion scan (PIS) approach using negative electrospray ionization-triple quadrupole mass spectrometry (ESI-QqQMS) was adopted and further optimized for fast selective detection of brominated oxidation products of TBrBPA by Mn(VII). By setting PIS of m/z 79 and 81, two major products (i.e., 4-(2-hydroxyisopropyl)-2,6-dibromophenol and 4-isopropylene-2,6-dibromophenol) and five minor ones (including 2,6-dibromophenol, 2,6-dibromo-1,4-benzoquinone, and three dimers) were detected and suggested with chemical structures from their product ion spectra and bromine isotope patterns. Reaction pathways mainly involving the initial one-electron oxidation of TBrBPA and subsequent release and further reactions of 2,6-dibromo-4-isopropylphenol carbocation intermediate were proposed. The effectiveness of Mn(VII) for treatment of TBrBPA in real waters was confirmed. It is important to better understand the reactivity and toxicity of primary brominated products before Mn(VII) can be applied for treatment of TBrBPA-contaminated wastewater and source water.
authors.affiliation: Key laboratory of Green Chemical Engineering and Technology of College of Heilongjiang Province, College of Chemical and Environmental Engineering, Harbin University of Science and Technology , Harbin 150040, China.
authors.forename: Su-Yan
authors.initials: SY
authors.lastname: Pang
authors.forename: Jin
authors.initials: J
authors.lastname: Jiang
authors.forename: Yuan
authors.initials: Y
authors.lastname: Gao
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhou
authors.forename: Xiaoliu
authors.initials: X
authors.lastname: Huangfu
authors.forename: Yongze
authors.initials: Y
authors.lastname: Liu
authors.forename: Jun
authors.initials: J
authors.lastname: Ma
mesh_terms: D005411:Flame Retardants / Q000032:analysis*; D005618:Fresh Water / Q000737:chemistry; D007700:Kinetics; D015394:Molecular Structure; D010084:Oxidation-Reduction; D011075:Polybrominated Biphenyls / Q000032:analysis* / Q000737:chemistry; D011196:Potassium Permanganate / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D062065:Wastewater / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000737:chemistry; D018508:Water Purification / Q000379:methods*
chemical_list: D005411:Flame Retardants; D011075:Polybrominated Biphenyls; D011196:Potassium Permanganate; D062065:Wastewater; D014874:Water Pollutants, Chemical; C020806:tetrabromobisphenol A