Equilibrium, Kinetic and Thermodynamic Study of Magnetic Polyaniline/Graphene Oxide Based Nanocomposites for Ciprofloxacin Removal from Water

In the present study, an adsorbent based on polyaniline-magnetic graphene oxide nanocomposite (MGO@PANI) was synthesized via in situ polymerization of an aniline monomer using ammonium persulfate as an oxidant in acidic medium for enhanced removal of ciprofloxacin (CIP) from aqueous solution. The surface functionality, morphology and elemental composition of the newly synthesized MGO@PANI were analyzed by FT-IR, FE-SEM, and EDX techniques. The adsorption efficacy of MGO@PANI was evaluated by monitoring the adsorption behavior of CIP antibiotic from aqueous samples. The effective factors on CIP adsorption such as solution pH, adsorbent dosage, contact time, concentration and temperature were investigated. The results revealed that MGO@PANI exhibits high adsorption efficiency with 97% removal of CIP (pH 6, dosage 20 mg, time 30 min at room temperature). The experimental data were well fitted to Freundlich adsorption isotherm suggesting multilayer pattern for adsorption process and the adsorption kinetics followed pseudo-second-order kinetics. Additionally, the thermodynamic study revealed that the CIP adsorption onto MGO@PANI was endothermic and indicated chemisorption mechanism.