title: Evaluation of the relationship between bulk organic precursors and disinfection byproduct formation for advanced oxidation processes.
abstract: Advanced oxidation processes (AOPs) are gaining traction as they offer mineralization potential rather than transferring contaminants between media. However, AOPs operated with limited energy and/or chemical inputs can exacerbate disinfection byproduct (DBP) formation, even as precursors such as dissolved organic carbon, UV254, and specific UV absorbance (SUVA) decrease. This study examined the relationship between DBP precursors and formation using TiO2 photocatalysis experiments, external AOP and non-AOP data, and predictive DBP models. The top-performing indicator, SUVA, generally correlated positively with trihalomethanes and haloacetic acids, but limited-energy photocatalysis yielded contrasting negative correlations. The accuracy of predicted DBP values from models based on bulk parameters was generally poor, regardless of use and extent of AOP treatment and type of source water. Though performance improved for scenarios bounded by conditions used in model development, only 0.5% of the model/dataset pairings satisfied all measured parameter boundary conditions, thereby introducing skepticism toward model usefulness. Study findings suggest that caution should be employed when using bulk indicators and/or models as a metric for AOP mitigation of DBP formation potential, particularly for limited-energy/chemical inputs.
authors.affiliation: Marquette University, P.O. Box 1881, Milwaukee, WI 53201-1881, United States. Electronic address: Brooke.Mayer@marquette.edu.
authors.forename: Brooke K
authors.initials: BK
authors.lastname: Mayer
authors.affiliation: Arizona State University, P.O. Box 875306, Tempe, AZ 85287-5306, United States.
authors.forename: Erin
authors.initials: E
authors.lastname: Daugherty
authors.affiliation: Arizona State University, P.O. Box 875306, Tempe, AZ 85287-5306, United States.
authors.forename: Morteza
authors.initials: M
authors.lastname: Abbaszadegan
mesh_terms: D002384:Catalysis; D004203:Disinfection / Q000379:methods*; D008962:Models, Theoretical; D010084:Oxidation-Reduction; D055668:Photochemical Processes; D010865:Pilot Projects; D014025:Titanium / Q000737:chemistry; D022882:Trihalomethanes / Q000032:analysis* / Q000737:chemistry; D014466:Ultraviolet Rays; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000737:chemistry; D018508:Water Purification / Q000379:methods*
chemical_list: D022882:Trihalomethanes; D014874:Water Pollutants, Chemical; C009495:titanium dioxide; D014025:Titanium
keywords: Advanced oxidation; Disinfection byproduct; Haloacetic acid; Model; Titanium dioxide photocatalysis; Trihalomethane