Preparation and characterization of magnetic rectorite/iron oxide nanocomposites and its application for the removal of the dyes

The superparamagnetic Fe3O4 nanoparticles were synthesized on the rectorite (REC) to prepare the adsorbent of magnetic REC (REC-Fe3O4), which was explored to adsorb three dyes, namely methylene blue (MB), neutral red (NR) and methyl orange (MO). Characterization of REC-Fe3O4 by Fourier transform infrared spectroscopy, transmission electron microscopy and X-ray diffraction showed that REC was attached with clusters of Fe3O4 nanoparticles. And the galleries in the REC were partially exfoliated when Fe3O4 were formed on the new surface of REC. There were still some galleries, which were not exfoliated in REC-Fe3O4. Magnetic properties revealed that REC-Fe3O4 was superparamagnetic with a saturation magnetization (19.14 emu/g). The adsorption behavior of REC and REC-Fe3O4 illustrated that it exhibited good adsorption for MB and NR, while the adsorption of MO was very little. And REC-Fe3O4 was easily separated from the aqueous solution in a magnetic field.

► Fe3O4 nanoparticles were synthesized on REC to obtain magnetic sorbent REC-Fe3O4.
► REC-Fe3O4 was characterized.
► The galleries were partially exfoliated, Fe3O4 formed on the new surface of REC.
► Three dyes were adsorbed by REC and REC-Fe3O4.
► The adsorption for dyes was increased by REC when Fe3O4 attached on REC.