Dihydroxy bezladely derivatives functionalized mesoporous silica SBA-15 for the sorption of U(VI)

Three different modified SBA-15 have been synthesized by a post-grafting method using 3,4-dihydroxy benzaldehyde (OHBA), 2,4-dihydroxy benzaldehyde (MHBA), 2,4-dihydroxy acetophenone (RATP). These materials were characterized by NMR, TEM, FT-IR and elemental analysis. Batch experiments have been conducted to study the effects of pH, temperature, adsorbent dosage, ionic strength, shaking time, initial concentration of metal ion, and coexisting ions on uranium(VI) sorption behaviors of pure and functional SBA-15. In addition, the adsorption of U(VI) could be well-described by the Langmuir, Freundlich isotherms and pseudo-second kinetic models. The results suggest the sorption capacity and selectivity of SBA-15 were improved after functionalization. (author)