Synthesis, characterization and adsorption properties of Fe3O4 /MWCNT magnetic nanocomposites

In this work, a simple and efficient chemical method to prepare Fe3O4 magnetic nanoparticles decorated on multi-walled carbon nanotube (Fe3O4/MWCNT nanocomposites) was presented. Fe3O4 nanoparticles were prepared by chemical co-precipitation of Fe2+ and Fe3+ in alkaline solution. The average particle size diameter of the particles was approximately 12 nm. A mixture between the obtained colloidal solution of Fe3O4 nanoparticles and the colloidal dispersion of acid functionalized MWCNT in water resulted in uniformly Fe3O4 nanoparticles deposited on carbon nanotube. In basic solution, Fe3O4 nanoparticles were stably attracted to carboxylate groups (MWCNT-COO-) on the surface. The presence of Fe3O4 nanoparticles and their surface conjugation to MWCNT have been confirmed by XRD, TEM and FT-IR techniques. The effect of Fe3O4 loading on the X-ray diffraction patterns were determined to investigate their chemical and phase composition. Magnetic evaluation of the synthesized magnet revealed a strong magnetic separation property. The sorption properties of Fe3O4/MWCNT composites for the removal of methylene blue from aqueous solution were investigated. The effect of contact time and initial concentration of MB on the adsorption were fully studied. The result kinetic data were well followed by the pseudo-second-order model.