Bromate is a potential carcinogen and formed in treatment of bromide-containing water using ozone-based technologies.So

the study on bromate formation during removal of organic pollutions is necessary for applying UV/O3 process.The effects of water background

initial MTBE concentration

ozone dosage and dosing method on removal of methyl tert-butyl ether(MTBE)and formation of bromate were studied.Besides

the mechanism of action for ozone dosing method was explored.The results showed that MTBE removal rates obtained by UV/O3 process in ultrapure water and tap water were 93.5% and 88.67%

and bromate concentration were 18.01 μg·L-1 and 12.13 μg·L-1

respectively

which were higher than the standard value of 10 μg·L-1.The promotion of initial MTBE concentration inhibited bromate formation

but longer reaction time were compulsory since MTBE concentration was required to be lower than proposed concentration of 5 μg·L-1.In this case

bromate formation was eventually enhanced.Increase of ozone dosage was favorable for MTBE removal

but caused decline of the utilization rate of ozone and the promotion of bromate formation.Comparing three ozone dosing methods in which the same ozone dosage of 5 mg·min·L-1 was applied

the highest hydroxyl radical(·OH)exposure and minimum ozone exposure were obtained in the method at ozone concentration of 0.75 mg·L-1 and reaction time of 120 min.Therefore

the concentrations of MTBE and bromate in water both met the standard values after treatment.