Iranian Journal of

Background and Objectives: Among the different types of antibiotics, tetracycline antibiotics are the second most common group around the world that their entrance into domestic sewage can result in contamination of water sources. The aim of this study was to investigate the efficacy of the nano-sonocatalytic process on removal of tetracycline antibiotics from aqueous solutions. Materials and Methods: In this study, the effectiveness of ultrasonic irradiation without and with TiO₂ nanoparticles and hydrogen peroxide were studied in tetracycline antibiotics removal. For this purpose, a reactor different concentrations of tetracycline was exposed to two irradiation frequencies of 35 and 130 KHz. Concentration of residual antibiotic was measured using HPLC equipped with a C18 reverse phase column and a UV detector. Results: It was found that the efficacy of ultrasonic irradiation alone in removal of this pollutant was negligible and at the best conditions only 20.3% removal was achieved at the frequency of 35 KHz. Addition of TiO2 nanoparticles improved the removal efficiency the removal rate increased with the increase in TiO₂ concentration until 250 mg/L, after which it remained approximately stable. The best removal efficiency was achieved by adding 100 mg/l hydrogen peroxide to US/TiO₂ process at pH 4 in which 94.3% removal was achieved after 60 minute. Conclusion: The results of this study showed that the sonocatalytic process using TiO₂ nanoparticles and along with adding H₂O₂ as an oxidant is very effective and can be used for removal of tetracycline antibiotics from aqueous solutions.