Enhanced degradation of Tetrabromobisphenol A in water by a UV/base/persulfate system: Kinetics and intermediates

Tetrabromobisphenol A (TBBPA), one of the most frequently used brominated flame retardants (BFRs), is only soluble in strongly alkaline solutions where most advanced oxidation processes (AOPs) are inefficient or in organic solvents. It is highly desirable to develop an environmentally friendly cleanup technology for TBBPA which operates at alkaline pH without the need of organic solvents to enhance its solubility in water. In this study a favorable UV/base/persulfate (PS) system for rapid degradation of TBBPA in aqueous solution is reported. Increases of initial pH and PS concentrations have positive effects on the degradation of TBBPA and a high initial TBBPA concentration has a negative influence. The addition of Br^- has a negligible effect on the degradation of TBBPA. The low TOC removal and degradation intermediates of TBBPA identified by GC-MS suggested that TBBPA was degraded via the cleavage between the isopropyl group and one of the benzene rings rather than complete debromination and degradation. The present study provides a simple and green approach to detoxify TBBPA in water rather than using toxic organic solvents.