Fabrication of alginate-based nanofibers loaded with ZnO nanoparticles for adsorption of tetracyclines from environmental waters

Residual tetracyclines (TCs) in the aquatic environment are a prominent issue due to their long environmental half-life and toxicity to the ecosystem and human health. Therefore, it is urgently necessary to develop low-cost and eco-friendly materials to remove TCs from environmental waters. Herein, the alginate-based nanofibers loaded with ZnO nanoparticles (ZnO/SA-NFs) were fabricated through an electrospinning approach. The nanofibers are porous materials with a Brunauer-Emmett-Teller surface area of 5.443 m(2) g(-1) and a pore diameter of 19.0 nm. The adsorption kinetics data favor the pseudo-second-order model, and the adsorption isotherms data follow the Liu model well. The adsorption capacities of tetracycline, oxytetracycline, and doxycycline were 248.6, 244.5, and 388.6 mg g(-1), respectively. The thermodynamic study suggested that the adsorption of TCs on ZnO/SA-NFs was spontaneous and endothermic. Research on the adsorption mechanism indicated that the synergistic action of ZnO and SA was responsible for improving the adsorption capacity of TCs. More importantly, this material showed excellent removal performance for TCs in actual water samples, suggesting that the composite nanofibers will have tremendous prospects in the remediation of TCs-contaminated water.