Results and discussion
Synthesis and characterization
Nano-Fe3O4, is produced as previously described [2] by the
combination of Fe(II) and Fe(III) in an alkaline solution to form the
hydroxide precipitate forms of Fe(OH)2 and Fe(OH)3, respectively.
Simultaneous precipitation and adsorption of these two hydroxides
occur for the formation of Fe3O4 with the loss of water
molecule. The produced nano-Fe3O4 particles can be collected and
separated from the aqueous solution by the action of an external
magnetic field. The second synthesized sorbent, in this work, is
based on the addition and surface encapsulation of nano-Fe3O4 by
DOP to form the nano-Fe3O4-DOP sorbent. Finally, the third
modified magnetic nano-sorbent was based on the direct reaction
of triethylentetramine (TETA), as a nitrogen containing sequestering
agent, with nano-Fe3O4-DOP for the formation of a newly
synthesized nano-Fe3O4-DOP-TETA sorbent. The three magnetic
nano-sorbents were characterized by several instrumental and
surface techniques such as thermal gravimetric analysis (TGA),
Fourier transform-infrared (FT-IR), scanning electron microscopy
(SEM) and high resolution transmission electron microscopy
(HR-TEM).