Sorption capacities of chitosan/polyethylene oxide (PEO) electrospun nanofibers used to remove ibuprofen in water

Pharmaceutical residues coming from urban wastewater were recognized as a major source of pollution for the aquatic environment. Their occurrence in most municipal effluent seems to indicate that conventional wastewater treatments have only a limited ability to remove such substances from sewage. Therefore, the undesired effects caused by these emergent contaminants on the environment force the authorities to consider new measures to treat and recycle contaminated water. In this study, electrospun nanofibers made of chitosan and poly(ethylene oxide) (PEO) were used to remove the anti-inflammatory drug ibuprofen in solution. The electrospinning parameters such as the mixture solution concentration, applied voltage, distance needle-collector, and flow rate were optimized to get the best nanofiber morphology characterized by scanning electron microscopy (SEM). With the use of a high-performance liquid chromatography with ultraviolet diode array detection (HPLC-UV DAD) system, sorption tests were performed by modifying experimental conditions, e.g. pH, concentration of ibuprofen, and temperature of the tested solutions. Langmuir, Freundlich, and Dubinin-Radushkevich (DR) adsorption models were compared for the mathematical description of adsorption equilibria. Kinetic assays showed that the adsorption of chitosan nanofiber followed a pseudo-second-order model. After 20 min of exposure, 25 mg of nanofiber had removed 70% of the initial ibuprofen concentration.