Electrospun Cellulose Acetate–Polycaprolactone/Chitosan Core–Shell Nanofibers for the Removal of Cr(VI)

Abstract

Core–shell‐structured cellulose acetate–polycaprolactone/chitosan (CA–PCL/CS) nanofibers with excellent removal performance of hexavalent chromium (Cr(VI)) are developed by coaxial electrospinning. The effect of core‐to‐shell ratio on adsorption capability is studied. The results show that all core–shell‐structured fibers possess higher adsorption capability and good durability in acidic environment compared with the CS powder adsorbent. CA–PCL/CS fibers with core‐to‐shell ratio of 0.442 have a maximum adsorption capability of 126 mg g −1 at room temperature. The adsorption kinetics reveals that chemisorption serves as the rate‐determining step by notable electron transfer, share, or exchange between adsorbents and adsorbates. The adsorption equilibrium data of the core–shell‐structured CA–PCL/CS fiber adsorbents are all well described by the Freundlich isotherm model, indicating the multilayer adsorption process. Herein, it is highlighted that the core–shell‐structured CA–PCL/CS nanofibers have a promising prospect in removing Cr(VI) ions from waste water.