title: Degradation of quinolone antibiotic, norfloxacin, in aqueous solution using gamma-ray irradiation.
abstract: This study reports the efficiency of gamma-ray irradiation to degrade quinolone antibiotic, norfloxacin, in aqueous solution. Laboratory batch experiments were conducted to determine the "pseudo-first" order degradation kinetics of norfloxacin in the concentration ranges of 3.4-16.1 mg L(-1) by gamma-ray irradiation. The dose constant was found to be dependent on the initial concentration of norfloxacin and gamma-ray irradiation dose rate (D r). The saturation of norfloxacin sample solutions with N2, air or N2O, and the presence of tert-butanol and 2-propanol showed that (•)OH played more crucial role in the degradation of norfloxacin. The second order rate constants of (•)OH, eaq (-), and (•)H with norfloxacin were calculated to be 8.81 × 10(9), 9.54 × 10(8), and 1.10 × 10(9) M(-1) s(-1), respectively. The effects of various additives including CO3 (2-), HCO3 (-), NO3 (-), NO2 (-), and thiourea and the pH of the medium on the degradation of norfloxacin were also investigated. Norfloxacin degradation was lower in surface water and wastewater than in ultrapure water. Several degradation byproducts of norfloxacin were identified from which the possible degradation pathway was proposed.
authors.affiliation: Radiation and Environmental Chemistry Laboratory, National Centre of Excellence in Physical Chemistry, University of Peshawar, Peshawar, 25120, Pakistan. murtazasayed@upesh.edu.pk.|Department of Chemistry, COMSATS Institute of Information Technology, Abbotabad, 22060, Pakistan. murtazasayed@upesh.edu.pk.
authors.forename: Murtaza
authors.identifier: http://orcid.org/0000-0002-2194-8058
authors.initials: M
authors.lastname: Sayed
authors.affiliation: Radiation and Environmental Chemistry Laboratory, National Centre of Excellence in Physical Chemistry, University of Peshawar, Peshawar, 25120, Pakistan.
authors.forename: Javed Ali
authors.initials: JA
authors.lastname: Khan
authors.affiliation: Radiation and Environmental Chemistry Laboratory, National Centre of Excellence in Physical Chemistry, University of Peshawar, Peshawar, 25120, Pakistan.
authors.forename: Luqman Ali
authors.initials: LA
authors.lastname: Shah
authors.affiliation: Radiation and Environmental Chemistry Laboratory, National Centre of Excellence in Physical Chemistry, University of Peshawar, Peshawar, 25120, Pakistan.|Department of Environmental Sciences, COMSATS Institute of Information Technology, Vehari, 61100, Pakistan.
authors.forename: Noor S
authors.initials: NS
authors.lastname: Shah
authors.affiliation: Radiation and Environmental Chemistry Laboratory, National Centre of Excellence in Physical Chemistry, University of Peshawar, Peshawar, 25120, Pakistan. hmkhan@upesh.edu.pk.
authors.forename: Hasan M
authors.initials: HM
authors.lastname: Khan
authors.affiliation: Radiation and Environmental Chemistry Laboratory, National Centre of Excellence in Physical Chemistry, University of Peshawar, Peshawar, 25120, Pakistan.
authors.forename: Faiza
authors.initials: F
authors.lastname: Rehman
authors.affiliation: Department of Chemistry, COMSATS Institute of Information Technology, Abbotabad, 22060, Pakistan.
authors.forename: Abdur Rahman
authors.initials: AR
authors.lastname: Khan
authors.affiliation: Department of Chemistry, COMSATS Institute of Information Technology, Abbotabad, 22060, Pakistan.
authors.forename: Asad M
authors.initials: AM
authors.lastname: Khan
mesh_terms: D019840:2-Propanol; D000900:Anti-Bacterial Agents; D005720:Gamma Rays; D007700:Kinetics; D009643:Norfloxacin / Q000528:radiation effects*; D010084:Oxidation-Reduction; D062065:Wastewater; D014867:Water; D014874:Water Pollutants, Chemical / Q000528:radiation effects*; D018508:Water Purification; D060753:Water Quality
chemical_list: D019840:2-Propanol; D000900:Anti-Bacterial Agents; D009643:Norfloxacin; D062065:Wastewater; D014867:Water; D014874:Water Pollutants, Chemical
keywords: Additives; Degradation kinetics; Degradation pathways; Gamma-ray irradiation; Norfloxacin; Water decontamination