Synthesis of amine-functionalized MCM-41 and its highly efficient sorption of U(VI)

Herein, the amine-functionalized MCM-41 mesoporous silica (denoted as MCM-41-NH2) was synthesized and applied to adsorption and recovery U(VI) ions from aqueous solutions. The results showed that the sorption of U(VI) on MCM-41-NH2 was strongly dependent on pH and ionic strength. The sorption was mainly dominated by outer-sphere surface complexation and the sorption equilibrium can be reached within 60 min. The maximum sorption capacity of MCM-41-NH2 for U(VI) was calculated to be 386.98 mg g−1 at pH 5.60, much higher than that of the other reported materials.