A unified approach to the analysis of polar organic by-products of oxidation in aqueous matrices

Information on the identification and occurrence of polar by-products of oxidation in water treatment is limited due to the difficulty in isolating these compounds from the aquatic matrix. A scheme has been developed which permits the simultaneous recovery and pre-concentration of mono- and multifunctional carbonyl-containing species from a single aqueous sample. Subsequent target-specific derivatization permits the identification of aldo- and ketoacids and hydroxy carbonyl species as well as aldehydes, ketones, dialdehydes and ketoaldehydes. The same aqueous sample can be pre-concentrated on an in-line ion exchange column for analysis of organic acids by ion chromatography. An additional sample can be analyzed through selective generation of OH radicals forming a fluorophore for determination of organic peroxides. Positive chemical ionization ion trap mass spectrometry is effectively utilized for identification of the derivatized carbonyl-containing species and following structural confirmation through analysis of standards, the analysis scheme is applied to ozonated aqueous solutions. A cationic polymer, commonly used in drinking water treatment, produces trace levels of each of the derivatized fractions. An ozonated surface water is analyzed for the carbonyl-containing species and also for the formation of peroxides.