Sorption of Uranium and other Metal Ions on Amine-Functionalized Silica Materials

Abstract

Sorption of U(VI) and other metal ions on amine-functionalized silica was studied, including aminopropylsilica (APS), 3-(ethylenediamino)propyl silica (ENPS), and 3-[2-(2-aminoethylamino)ethylamino]propyl silica (DIENPS). DIENPS showed the strongest and fastest sorption for U(VI) that can be described by Langmuir isotherm, suggesting U(VI) was sorbed at well-defined and energetically identical sites independent from each other. The sorption efficiency of DIENPS follows the order: U(VI) > Fe(III) > Cu(II) > Pb(II) > Ni(II) > Mg(II) > Sr(II). Results demonstrate that the amine-functionalized silica materials could be used as efficient sorbents to remove uranium and hazardous metal ions in environmental remediation.

Keywords:

• uranium
• sorption
• amine-functionalized silica

Notes

* Equation (3) is valid only when the volumes of the aqueous solutions in the sorption and desorption experiments are identical.

Additional information

Funding

The preparation of the functionalized silica materials was conducted at University of Padova (UP), Italy, and supported by the Heavy Element Chemistry Program, Office of Basic Energy Science of the U. S. Department of Energy (DOE) through a subcontract with UP. The sorption experiments were conducted at Lawrence Berkeley National Laboratory (LBNL) and supported by the Fuel Resources Program, Fuel Cycle Research and Development Program, Office of Nuclear Energy of the U.S. DOE, under Contract No. DE-AC02-05CH11231.