Adsorption process of fluoride from drinking water with magnetic core-shell Ce-Ti@Fe3O4 and Ce-Ti oxide nanoparticles

Abstract Synthesized magnetic core-shell Ce-Ti@Fe 3 O 4 nanoparticles were tested, as an adsorbent, for fluoride removal and the adsorption studies were optimized. Adsorption capacity was compared with the synthesized Ce-Ti oxide nanoparticles. The adsorption equilibrium for the Ce-Ti@Fe 3 O 4 adsorbent was found to occur in 3 O 4 nanoparticles, respectively. The physical sorption mechanism was estimated using the Dubinin-Radushkevich model. An anionic exchange process between the OH − group on the surface of the Ce-Ti@Fe 3 O 4 nanomaterial and the F − was involved in the adsorption. Moreover, thermodynamic parameters proved the spontaneous process for the adsorption of fluoride on Ce-Ti@Fe 3 O 4 nanoparticles. The reusability of the material through magnetic recovery was demonstrated for five cycles of adsorption-desorption. Although the nanoparticles suffer slight structure modifications after their reusability, they keep their adsorption capacity. Likewise, the efficiency of the Ce-Ti@Fe 3 O 4 was demonstrated when applied to real water to obtain a residual concentration of F − below the maximum contaminated level, 1.5 mg/L (WHO, 2006).