Effect of several natural water constituents on bromate formation during ozonation

Synthetic water matrices containing ammonia, bicarbonate, hydrogen peroxide, and natural organic matter were studied to identify the effects of these compounds (individually arid in combination) on bromate formation. Ammonia alone was observed to significantly reduce bromate formation through the sequestering of brominated intermediates as bromamines. Natural organic matter reacted quickly with bromamines, which could impair the ability of ammonia to block bromate formation. Bicarbonate was observed to generally promote bromate formation in otherwise pure water, but bicarbonate worked synergistically with ammonia to reduce bromate formation by a greater factor than ammonia alone, due to OH radical scavenging. Experiments showed that hydrogen peroxide lowered the effectiveness of ammonia to block bromate formation.