FORMATION OF ALDEHYDES DURING OZONATION

This study investigated the formation of aldehydes after ozonation of three real and three model waters reconstituted from hydrophobic organ ic material. The four main aldehyde species formaldehyde, acetaldehyde , glyoxal, and methyl glyoxal were analyzed. Formaldehyde was the domi nant species formed as a result of ozonation. The different waters var ied greatly with respect to aldehyde production under similar treatmen t conditions. Studies conducted with model waters allowed for explorin g aldehyde formation as a function of various water quality parameters . Overall, the hydrophobic organic extracts appeared to have greater a ldehyde formation potential than the hydrophilic organics. Aldehydes w ere formed in direct proportion to the total organic carbon (TOC) conc entration of the water at a 1:1 ozone-to-TOC ratio. Greater aldehyde f ormation was observed at lower ozonation pH values. Bromide ion and in organic carbon added to model waters appeared to have no effect on ald ehyde production. Finally, Assimilable Organic Carbon (AOC) measuremen ts exhibited a strong correlation between aldehyde production and AOC production.