| Abstract [eng] |
The use of antibiotics in human medicine, livestock, and aquaculture has increased significantly [1] and the dangers posed by pharmaceuticals and their reaction products have become common knowledge resulting in increased research activities [2]. Aside from the risk of supporting microbial antibiotic resistance, antibiotic residues can harm various trophic biological levels and human health, potentially causing ecotoxicological effects [3]. Although TiO2 has been widely applied a limited number of studies using TiO2 nanotube arrays for photocatalytic water treatment are available [4]. This study aimed to develop and test TiO2 nanotube arrays (NTAs) photocatalytic ozonation reactors, as one of the most effective advanced oxidation processes (AOP), to treat antibiotics in a model secondary effluent. MATERIALS AND METHODS TiO2 NTAs were prepared according to the description in [5]. Wastewater was prepared with a concentration of 10mg/l of Ciprofloxacin (CIP) in demineralized water. Using six AOPs (photolysis, ozonation, ozone photolysis, photocatalytic ozonation, UV photocatalysis and catalytic ozonation), experiments were carried out ranging from 5 minutes to 60 minutes. For ozone experiments, the concentration of ozone was approximately 5mg/l. RESULTS AND DISCUSSION The photocatalytic ozonation process was identified as the most effective process in the removal of CIP. CIP was degraded in 7 minutes, therefore, having a 100% efficiency. The pseudo-second-order kinetics varied from 1.01 x 10-1 min-1 to 1.33 x 10-1 min-1 based on the initial concentration of CIP in the model water. Photolytic treatment and photocatalytic ozonation resulted in 51–66% and 92–100% removal efficiency of antibiotic CIP. However, in all cases where ozone was used, there was complete removal of CIP. |
