Electrospinning of polyacrylonitrile nanofibers embedded with zerovalent iron and cerium oxide nanoparticles, as Cr(VI) adsorbents for water treatment

Zerovalent iron (ZVI) and cerium oxide (CeO2) nanoparticles (NPs) embedded in polyacrylonitrile nanofibers (NFs) were obtained via electrospinning. Each NF was characterized using Fourier transform infrared spectroscopy and X-ray diffraction. The scaffold morphology and average diameter of the NFs were determined using scanning electron microscopy (SEM). Energy dispersive X-ray spectroscopy (EDS) mapping and Raman spectroscopy were used to characterize the NPs dispersion in the NFs. The Cr(VI) removal efficiency (%E) of ZVI and CeO2 NPs was compared with the efficiency of their corresponding NFs. CeO2 NPs showed 79% Cr(VI) removal; the efficiency was better for their NFs (96%). Regeneration of ZVI NFs was 98 %E. ZVI NPs were the best adsorbent with 99.9% efficiency. An adsorption mechanism was proposed using Langmuir, Freundlich, and Temkin isotherm models. SEM-EDS analyses revealed that Cr adsorbed on the NP and NF surfaces. (c) 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 137, 48663.