title: Degradation of antibiotics norfloxacin by Fenton, UV and UV/H2O2.
abstract: This study aimed to evaluate the degradation of the antibiotic norfloxacin, using direct photolysis (UV), photolysis with hydrogen peroxide (UV/H2O2) and Fenton's oxidation processes. Initially, it was evaluated the behavior of the antibiotic norfloxacin on direct photolysis, in order to see if the process could be a pertinent way to eliminate the drug in water treatment stations. The results showed that the use of direct photolysis was not effective in the degradation of the antibiotic, reaching a degradation rate of 85% and a mineralization rate of 2% in 7 h of reaction; leading to the formation of intermediates products. To optimize the UV treatment, it was used the combined UV/H2O2 process. Several concentrations of hydrogen peroxide (0.7, 1.4, 2.1, 2.8, 3.5 and 4.2 mmol/L) at pH 7 were tested. The concentration of 2.1 mmol/L reached a degradation rate of 100% in 100 min of reaction. Based on this result, the speed of the reaction at pH 2, 3, 5, and 10 was evaluated for that same concentration of H2O2. The shortest reaction time (60 min) was verified at pH 2 and 3. For the treatment using Fenton oxidation, a degradation rate of 60% of the compound and a mineralization rate of 55% was obtained in 60 min. The study revealed that the Fenton oxidation and UV/H2O2 can be used for norfloxacin removal, reaching respectively degradation rates of 100% and 60%, and mineralization rates of 55% and 32%.
authors.affiliation: Department of Sanitary and Environmental Engineering, Federal University of Minas Gerais, 6627 Antônio Carlos Avenue, Campus Pampulha, Belo Horizonte, MG, Brazil. Electronic address: lucilainevaleria@yahoo.com.br.
authors.forename: Lucilaine Valéria de Souza
authors.initials: LV
authors.lastname: Santos
authors.affiliation: Department of Chemistry, Federal University of Minas Gerais, 6627 Antônio Carlos Avenue, Campus Pampulha, Belo Horizonte, MG, Brazil.
authors.forename: Alexandre Moreira
authors.initials: AM
authors.lastname: Meireles
authors.affiliation: Department of Sanitary and Environmental Engineering, Federal University of Minas Gerais, 6627 Antônio Carlos Avenue, Campus Pampulha, Belo Horizonte, MG, Brazil.
authors.forename: Liséte Celina
authors.initials: LC
authors.lastname: Lange
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000528:radiation effects*; D052918:Environmental Restoration and Remediation / Q000379:methods*; D006861:Hydrogen Peroxide / Q000737:chemistry*; D007501:Iron; D009643:Norfloxacin / Q000737:chemistry*; D010084:Oxidation-Reduction; D010777:Photochemistry; D010782:Photolysis; D014466:Ultraviolet Rays; D014874:Water Pollutants, Chemical / Q000528:radiation effects*; D018508:Water Purification / Q000379:methods*
chemical_list: D000900:Anti-Bacterial Agents; C045076:Fenton's reagent; D014874:Water Pollutants, Chemical; D006861:Hydrogen Peroxide; D007501:Iron; D009643:Norfloxacin
keywords: Fenton's oxidation; Norfloxacin; Photolysis; UV/H(2)O(2)