Removal of Pb(II) and Cu(II) from aqueous solution using multiwalled carbon nanotubesiron oxide magnetic composites

摘要

Multiwalled carbon nanotubes (MWCNTs)/iron oxide magnetic composites (named as MCs) werenprepared by co-precipitation method, and were characterised by scanning electron microscopen(SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) in detail. The preparednMCs were employed as an adsorbent for the removal of Pb(II) and Cu(II) ions from wastewater innheavy metal ion pollution cleanup. The results demonstrated that the sorption of Pb(II) and Cu(II)nions was strongly dependent on pH and temperature. The experimental data were well describednby Langmuir model, and the monolayer sorption capacity of MCs was found to vary from 10.02 ton31.25 mg/g for Pb(II) and from 3.11 to 8.92 mg/g for Cu(II) at temperature increasing from 293.15nto 353.15 K at pH 5.50. The sorption capacity of Pb(II) on MCs was higher than that of Cu(II), whichnwas attributed to their ionic radius, hydration energies and hydrolysis of their hydroxides. Thenthermodynamic parameters (i.e., DH0, DS0 and DG0) were calculated from temperature dependentnsorption isotherms, and the results indicated that the sorption of Pb(II) and Cu(II) ions on MCsnwere spontaneous and endothermic processes.