Shahriar Osfouri

Human health can be affected by heavy metals, so their elimination is essential. In recent years, electrospun nanofibers have attracted researchers' attention for their adsorption potential. In this work, by electrospinning Polyethylene oxide/Chitosan (PEO/CS) and Polyvinyl alcohol/Chitosan (PVA/CS), it is shown that PVA/CS nanofibers in a 90:10 ratio have appropriate morphological properties without beads. The number of beads and the diameter of nanofibers has increased with an increase in CS percentage. As a result of the TGA experiment, it was demonstrated that CS had excellent thermal stability, and adding it to the PVA made the nanofibers more resistant to thermal degradation. FTIR experiment showed that hydrogen bonds were formed when two polymers were mixed. Based on the XRD results, the nanofibers exhibit three peaks related to their crystallization at 12, 20, and 42°. Comparing the absorption of copper (Cu) and chromium (Cr) ions by PVA/CS nanofibers, it was found that Cr adsorption was better due to its higher positive charge density. Curve fitting results of experimental data on kinetic models showed that the first-order model is more suitable for Cr ion absorption, while the second-order pseudo-model and Elvich model are better for Cu ion absorption.