Gum kondagogu modified magnetic nano-adsorbent: An efficient protocol for removal of various toxic metal ions

Gum kondagogu (GK) modified magnetic iron oxide nanoparticles (MNP) have been prepared by co-precipitating Fe2 + and Fe3 + ions using ammonia solution in presence of GK biomacromolecules. The TEM analysis revealed the presence of nearly spherical size iron oxide particles with diameters in the range of 8−15 nm; while the XRD results confirmed the crystallinity of iron oxide nanoparticles. The magnetic measurements demonstrated the ferromagnetic behavior of GK − MNP with a magnetic saturation value of ~ 60 emu/g. The removal efficiencies for a variety of metal cations by the GK − MNP were determined quantitatively in the order: Cd2 + > Cu2 + > Pb2 + > Ni2 + > Zn2 + > Hg2 + at a pH of 5.0 ± 0.1 and at a temperature of 30.0 ± 1.0 °C. A maximum of 106.8 mg/g and a minimum of 35.07 mg/g adsorption capacities were observed for the Cd2 + and Hg2 + ions, respectively using the Langmuir isotherm model.

► Gum kondagogu grafted magnetic nanoparticles synthesized by aqueous precipitation.
► Magnetic composite composed of spherical iron oxide nanoparticles of size 8–15 nm.
► Magnetization value of ~ 60 emu/g estimated for the magnetic nanocomposite.
► Removal efficiency of magnetic nano-adsorbent verified for various toxic metals.