The adsorption performance of tetracyclines on magnetic graphene oxide: A novel antibiotics absorbent

Abstract As an easy-recycling absorbent, magnetic graphene oxide (MGO) can potentially adsorb tetracyclines (TCs) effectively. This study aimed to explore the adsorption mechanism of TCs on MGO. The influences of different environmental factors, such as solution pH and temperature, on MGO adsorption performance were also investigated. The pseudo-second-order kinetic model and Freundlich isotherm model provided the better correlation for the experiment data, indicating that the control of adsorption was mostly by physical and chemical means. The thermodynamic parameters showed that the adsorption followed a spontaneous and endothermic process. MGO has a better performance on absorbing chlortetracycline (CTC) under alkaline conditions, whereas it showed the best absorption of tetracycline hydrochloride (TC) and oxytetracycline (OTC) at pH 3.3. The MGO has potential as an easy-recycling adsorbent for TCs removal from aqueous solutions.