Investigating the removal of tetracycline antibiotic from aqueous solution using synthesized Fe3O4@cuttlebone magnetic nanocomposite

Abstract

The presence of antibiotics in aqueous media, and subsequently, their transfer to the environment and the entry of these compounds into the body of living organisms cause disturbances in living organisms and ecosystems. This study was aimed to evaluate the removal efficiency of tetracycline (TC) antibiotics from aqueous media by synthesized Fe3O4@Cuttlebone (Cb) magnetic nanocomposite. The Fe3O4@Cb magnetic nanocomposite was synthesized by co-precipitation method under green conditions and structurally investigated using the following techniques: Fourier transform infrared, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, mapping, X-ray diffraction, Brunauer-Emmett-Teller, and vibrating-sample magnetometer. Parameters affecting removal such as pH (3–11), initial concentration of TC (4–20 mg/L), adsorbent dosage (0.05–0.25 g/L), and contact time (15–115 min) were evaluated. The response surface methodology based on central composite design was used by Design-Expert 11 software to design the experiments and find the optimal conditions. The Fe3O4@Cb magnetic nanocomposite was synthesized at the nanometer scale (approximately 31 nm) with magnetic properties and high specific surface area. The quadratic model was identified as the best model by the software. The R2 and p values of lack of fit were 0.9723 and 0.0535, respectively. The optimal conditions for the removal of TC were pH 5, initial TC concentration of 8 mg/L, adsorbent dosage of 0.2 g/L, and contact time of 90 min. The maximum removal efficiency of TC using Fe3O4@Cb magnetic nanocomposite in synthetic conditions and simulated real wastewater was 80.15% and 75.34%, respectively. The Fe3O4@Cb magnetic nanocomposite had an effective potential to remove TC from aqueous solution.