Novel P@SiO2 Nano-Composite as Effective Adsorbent to Remove Methylene Blue Dye from Aqueous Media.

Abstract: This work aims to prepare a novel phosphate-embedded silica nanoparticles (P@SiO2)
nanocomposite as an effective adsorbent through a hydrothermal route. Firstly, a mixed solution
of sodium silicate and sodium phosphate was passed through a strong acidic resin to convert it
into hydrogen form. After that, the resultant solution was hydrothermally treated to yield P@SiO2
nanocomposite. Using kinetic studies, methylene blue (MB) dye was selected to study the removal
behavior of the P@SiO2 nanocomposite. The obtained composite was characterized using several
advanced techniques. The experimental results showed rapid kinetic adsorption where the equi
librium was reached within 100 s, and the pseudo-second-order fitted well with experimental data.
Moreover, according to Langmuir, one gram of P@SiO2 nanocomposite can remove 76.92 mg of the
methylene blue dye. The thermodynamic studies showed that the adsorption process was sponta
neous, exothermic, and ordered at the solid/solution interface. Finally, the results indicated that
the presence of NaCl did not impact the adsorption behavior of MB dye. Due to the significant
efficiency and promising properties of the prepared P@SiO2 nanocomposite, it could be used as an
effective adsorbent material to remove various cationic forms of pollutants from aqueous solutions in
future works.