Background: Improper use of antibiotics and their discharge into the environment have serious and dangerous consequences. About 30-30% of antibiotics are not metabolized in the body and enter the environment through urine and feces, so the main source of antibiotics in the environment is wastewater treatment plant effluent. The aim of this study was to investigate the removal efficiency of ciprofloxacin (CIP) from aqueous media by molecularly imprinted polymer (MIP). Methods: This study is an experimental-laboratory study performed in a reactor with a discontinuous system. In this study, the effect of parameters such as solution pH, adsorbent dose, initial concentration of CIP, reaction contact time and reaction temperature on the reduction rate the antibiotics amoxicillin and CIP were administered. Results: Results showed that removal efficiency for both antibiotics was increased with increasing contact time and adsorbent mass and initial antibiotics concentration while decreased with increasing solution pH and the best pH to remove was neutral pH. Equilibrium data were analyzed by Freundlich and Langmuir isotherm models and the results showed that the data from Langmuir isotherm had a higher correlation coefficient. In addition, the reaction rate was performed with pseudo-first-order and pseudo-second-order models, and the data were consistent with pseudo second order kinetic kinetics. According to result of thermodynamic study, entropy changes (ΔS O ), enthalpy changes (ΔH O ) and Gibbs free energy (ΔG O ) were negative that represent the adsorption process is spontaneous and exothermic. Conclusion:The results of this study showed that the process of adsorption of MIP is a very effective process for removing the CIP from aqueous solutions.

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Background: Antibiotics have lasting effects on the environment. Among the properties of these substances are non-biodegradable, carcinogenic, high toxicity, and an increase in antibiotic-resistant bacteria. Therefore, they should be removed from aqueous solutions and the point of this think was to adsorb amoxicillin (AMO) by magnetic graphene oxide nanocomposite (MGO). Methods: The adsorption behavior of AMO was studied in a series of batch experiments as a function of pH (3-11), contact time (0-120 min), and AMO concentration (10-100 mg/L) different MGO dosages (0.1-1 g/L). The structures of MGO were confirmed by scanning electron microscope (SEM), and the X-ray diffraction (XRD). Results:The results revealed in optimized conditions (pH=3, contact time=75 min, AMO concentration= 10mg/L and adsorbent dose=0.75 g/L) maximum adsorption capacity and removal efficiency of AMO were 98.41 mg/g, respectively. The thermodynamical parameters showed that the sorption method was endothermal and spontaneous. Conclusion: MGO nanoparticles have extended capabilities such as easy and rapid separation from solution and high potential in removing AMO, so, it can be introduced as an appropriate adsorbent for removal of this antibiotics from water and wastewater.