Sulfonated poly(arylene ether nitrile)/polypyrrole core/shell nanofibrous mat: an efficient absorbent for the removal of hexavalent chromium from aqueous solution

BACKGROUNDSulfonated poly(arylene ether nitrile)/polypyrrole core/shell nanofibrous mats were prepared by an electrospinning technique, followed by in situ polymerization of pyrrole monomer. Their removal of hexavalent chromium (Cr (VI)) from aqueous solution was systematically investigated. The structure and composition of core/shell PEN/PPy nanofibrous mats were examined and confirmed by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). RESULTSThe adsorption results revealed that the adsorption capacity of core/shell PEN/PPy nanofibrous mats increased with the decrease of initial solution pH and the adsorption process can be described by the pseudo-second-order model. These core/shell PEN/PPy nanofibrous mats showed high Cr (VI) adsorption capacity up to 165.3 mg g(-1) at room temperature, which can largely be maintained after four adsorption/desorption cycles. Furthermore, the adsorption isotherms of PEN/PPy nanofibrous mats for Cr(VI) removal fitted the Langmuir isotherm model. The adsorption mechanism of electrostatic attraction between PEN/PPy nanofibrous mats was also presented. CONCLUSIONThe core/shell PEN/PPy nanofibrous mats in the form of flexible membrane allowed easy handling during application, and can be considered a stable and effective adsorbent for removal of heavy metals and other anionic contaminants from wastewater. (c) 2017 Society of Chemical Industry