title: Kinetics and modeling of sulfonamide antibiotic degradation in wastewater and human urine by UV/H2O2 and UV/PDS.
abstract: Sulfonamide antibiotics have been frequently detected in the aquatic environment and are of emerging concern due to their adverse bio-effect and potential of inducing antibiotic resistance. This study investigated the degradation kinetics of sulfonamide antibiotics in synthetic wastewater and hydrolyzed human urine by low pressure (LP) UV, UV/H2O2 and UV/peroxydisulfate (PDS). Direct photolysis rates of sulfonamide antibiotics varied and depended on the structures. Sulfonamides with a five-membered heterocyclic group underwent faster direct photolysis. For indirect photolysis processes, second-order rate constants of sulfonamide antibiotics with hydroxyl radical, sulfate radical and carbonate radical were determined, which were (6.21-9.26) × 10(9), (0.77-16.1) × 10(10) and (1.25-8.71) × 10(8) M(-1) s(-1), respectively. A dynamic model was applied and successfully predicted the degradation kinetics of sulfonamides in different water matrices. In synthetic wastewater, carbonate radical contributed to approximately 10% of the overall removal, whereas in synthetic hydrolyzed urine, carbonate radical was the dominant reactive species to degrade sulfonamides. Sulfonamide antibiotics were eliminated more efficiently in synthetic hydrolyzed urine than in synthetic wastewater and UV/PDS was more efficient than UV/H2O2 to degrade most sulfonamides. Energy evaluation showed that UV/PDS costs less energy than LPUV and UV/H2O2 under the experimental conditions applied in this study, particularly for sulfonamides whose indirect photolysis overweighed direct photolysis. By varying UV dose and oxidant dose, the UV/H2O2 process can be optimized to achieve higher efficiency than the UV/PDS process in synthetic wastewater.
authors.affiliation: School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China.
authors.forename: Ruochun
authors.initials: R
authors.lastname: Zhang
authors.affiliation: School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China.
authors.forename: Yongkui
authors.initials: Y
authors.lastname: Yang
authors.affiliation: School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, United States.
authors.forename: Ching-Hua
authors.initials: CH
authors.lastname: Huang
authors.affiliation: School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China. Electronic address: zhaolin@tju.edu.cn.
authors.forename: Lin
authors.initials: L
authors.lastname: Zhao
authors.affiliation: School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, United States. Electronic address: sunpeizhe@gatech.edu.
authors.forename: Peizhe
authors.initials: P
authors.lastname: Sun
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry; D006801:Humans; D006861:Hydrogen Peroxide / Q000737:chemistry*; D007700:Kinetics; D010084:Oxidation-Reduction; D010782:Photolysis; D013449:Sulfonamides; D014466:Ultraviolet Rays; D062065:Wastewater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry
chemical_list: D000900:Anti-Bacterial Agents; D006861:Hydrogen Peroxide; D013449:Sulfonamides; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Advanced oxidation processes; Carbonate radical; Energy-cost evaluation; Kinetic modeling; Source separated urine; Sulfonamide antibiotics