title: Evolution of absorbance spectra of ozonated wastewater and its relationship with the degradation of trace-level organic species.
abstract: This study examined the evolution of absorbance spectra of wastewater ozonated using varying initial ozone concentrations or treatment times; concomitant changes of concentrations of trace-level pharmaceuticals were also quantified. The absorbance of ozonated wastewater decreased due to the degradation of chromophores in effluent organic matter (EfOM). The relative decrease of absorbance (DeltaA/A(0)) ranged from < 30% for lambda < 250 nm to > 80% for lambda > 320 nm. The removal of atenolol, carbamazepine, DEET, diclofenac, gemfibrozil, ibuprofen, iopromide, naproxen, propranolol, sulfamethoxazole, trimethoprim, and p-chlorobenzoic acid was strongly correlated with DeltaA/A(0) values. The observed features were hypothesized to correspond to the engagement of kinetically distinct groups of EfOM chromophores. Modeling of the evolution of EfOM absorbance and concurrent degradation of trace-level organic species based on this hypothesis confirmed its applicability and utility for practical applications and theoretical exploration.
authors: Department of Civil and Environmental Engineering, Box 352700, University of Washington, Seattle, Washington 98195-2700, USA.
authors: Venkateswarlu
authors: V
authors: Nanaboina
authors: Gregory V
authors: GV
authors: Korshin
mesh_terms: D003358:Cosmetics / Q000302:isolation & purification; D007700:Kinetics; D008956:Models, Chemical; D009930:Organic Chemicals / Q000302:isolation & purification*; D010084:Oxidation-Reduction; D010126:Ozone / Q000032:analysis*; D004364:Pharmaceutical Preparations / Q000302:isolation & purification; D013057:Spectrum Analysis; D014865:Waste Disposal, Fluid; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*
chemical_list: D003358:Cosmetics; D009930:Organic Chemicals; D004364:Pharmaceutical Preparations; D014874:Water Pollutants, Chemical; D010126:Ozone