ABSTRACT
The rate of ozone decomposition controls the yield of bromate and is influenced by water quality characteristics and water treatment parameters. Hypobromite ion (OBr−) and hydroxyl (HO) radical concentrations affect the extent and rate of bromate formation as well. Through the use of t-butanol as an HO radical scavenger, delineation of indirect HO radical and direct molecular ozone oxidation pathways are inferred. Approximately 75% of the bromate formation is controlled by HO radical mechanisms, while the remainder forms via molecular ozone mechanisms alone. Oxidation of bromine appears to be a critical oxidation step in either pathway.