(393bd) Magnetic Carbon Nanocomposites for Environmental Remediation

In-situ fabricated Fe@Fe₂O₃/graphene magnetic nanocomposites (MGNCs) and Fe@Fe₂O₃/polypropylene magnetic nanocomposites (MPPNCs) are tested  for the Cr (VI) removal from polluted water and their removal performances and efficiencies are compared. Both nanocomposites have demonstrated extremely fast Cr (VI) removal performances from polluted water, with the MGNCs exhibiting relatively higher removal efficiency with an almost complete removal of Cr (VI) within 5 min as compared to that of 10 min by MPPNCs.  The saturation magnetization of the MGNCs (96.3 emu/g) is also found to be greater than that of the MPPNCs (32.5 emu/g). The pH effect on the Cr(VI) removal efficiencies of the NCs is also investigated and the adsorbents have been found to exhibit much higher adsorption capacities in acidic solutions than in alkali solutions. Kinetic investigations reveal the pseudo-second order adsorption of Cr (VI) in both the cases. The significantly reduced treatment periods and easy recycling of the adsorbents from the liquid suspensions in a more energetically and economically sustainable way owing to their large saturation magnetizations makes these nanocomposites promising for the efficient removal of hazardous Cr (VI) from polluted water.