Efficient, rapid and simple adsorption method by polydopamine polystyrene nanofibers mat for removal of multi-class antibiotic residues in environmental water

Polydopamine polystyrene nanofibers mat (PDA-PS NFsM) was prepared as an adsorbent for the simultaneous removal of multiple antibiotic residues in environmental water for the first time. PDA-PS NFsM can directly be used to adsorb 18 antibiotic residues belonging to 8 classes without any pretreatment of water samples. The adsorption process was completed within 5 min. All antibiotics could be removed at the same time, and the removal rate of each target was above 85%. Moreover, the used PDA-PS NFsM can be easily separated from the environmental water by taking out directly, and can be reused for 10 times after simple regeneration. The thermodynamic and kinetic properties of PDA-PS NFsM adsorption of antibiotic residues were further investigated consequently. It was found that the adsorptions of PDA-PS NFsM to the targets were spontaneous and endothermic process (ΔG<0, ΔH>0, ΔS>0). The results of adsorption kinetic experiments illustrated that the adsorption process was rapid, the adsorption equilibrium of which can be reached in 5 min. Adsorption isotherm experiments proved that the adsorption process of PDA-PS NFsM was consistent with Langmuir adsorption (R2 > 0.994), and the maximum adsorption capacity of PDA-PS NFsM towards all targets were 123.76 mg g-1. The developed method is rapid and simple, and can efficiently adsorb and remove a variety of antibiotics in environmental water, which has good practical application prospect.