Photodegradation of tetracycline antibiotics in aqueous solution by UV/ZnO

AbstractPhotodegradation of three tetracycline antibiotics (TCs), tetracycline (TTC), oxytetracycline (OTC), and chlorotetracycline (CTC), by UV/ZnO were studied. The effects of ZnO concentration (0.5–2.0 g L−1) and solution pH (5–11) were evaluated. Results revealed that the photodegradation of TCs were enhanced by increasing ZnO dosage and solution pH. The TOC rose first and then fell during the photodegradation of TTC and CTC, which could be explained by the reaction sequences, i.e. adsorption, degradation, and then mineralization. Acute toxicity assessment indicated an obvious inhibitory effect and the increased toxicity of TCs photodegradation products on the growth of Photosbacterium phosphoreum T3 once the photodegradation reaction started. This research firstly investigated the photodegradation of TCs under UV/ZnO process, which would have a potential significance for the practical treatment of TCs wastewater.