Sono-activated persulfate oxidation of bisphenol A: Kinetics, pathways and the controversial role of temperature

Liquid chromatography time of flight mass spectrometry (LC-TOF-MS) analysis revealed the formation of twelve transformation by-products that accompany BPA sonodegradation in the presence of SPS. Based on their evolution profiles, a reaction mechanism is proposed consisting of two major pathways: (i) hydroxylation that can occur mainly in the aromatic ring through HO, SO4− radical attack and to a lesser extent in methyl groups, through hydrogen abstraction by HO radicals, with subsequent O2 addition, and (ii) scission of the bond between the isopropylidene carbon and the phenyl group.