Bisphenol A reactions with hydroxyl radicals: diverse pathways determined between deionized water and tertiary treated wastewater solutions

The oxidative reactions of bisphenol A (BPA) with radiolytically generated hydroxyl radicals were studied in both deionized water and tertiary treated wastewaters. In deionized water, bisphenol A reacts with the hydroxyl radical by addition to the aromatic ring, k = 6.9 x 10(9) (+/- 0.2) M-1 s(-1), to eventually form the prominent, long-lived, hydroxylated intermediate product. In contrast, in tertiary treated water solutions, although the initial hydroxyl radical addition reaction occurs, the hydroxylation is averted, and a different mechanistic pathway ensues. The removal constant for the hydroxyl radical reaction with BPA is 0.45 +/- 0.04 mu mol/kGy, corresponding to an overall degradation efficiency of 76%.