TY - JOUR
T1 - Efficient Uranium Capture by Polysulfide/Layered Double Hydroxide Composites
AU - Ma, Shulan
AU - Huang, Lu
AU - Ma, Lijiao
AU - Shim, Yurina
AU - Islam, Saiful M.
AU - Wang, Pengli
AU - Zhao, Li Dong
AU - Wang, Shichao
AU - Sun, Genban
AU - Yang, Xiaojing
AU - Kanatzidis, Mercouri G.
PY - 2015/3/18
Y1 - 2015/3/18
N2 - There is a need to develop highly selective and efficient materials for capturing uranium (normally as UO22+) from nuclear waste and from seawater. We demonstrate the promising adsorption performance of Sx-LDH composites (LDH is Mg/Al layered double hydroxide, [Sx]2- is polysulfide with x = 2, 4) for uranyl ions from a variety of aqueous solutions including seawater. We report high removal capacities (qm = 330 mg/g), large KdU values (104-106 mL/g at 1-300 ppm U concentration), and high % removals (>95% at 1-100 ppm, or ∼80% for ppb level seawater) for UO22+ species. The Sx-LDHs are exceptionally efficient for selectively and rapidly capturing UO22+ both at high (ppm) and trace (ppb) quantities from the U-containing water including seawater. The maximum adsorption coeffcient value KdU of 3.4 × 106 mL/g (using a V/m ratio of 1000 mL/g) observed is among the highest reported for U adsorbents. In the presence of very high concentrations of competitive ions such as Ca2+/Na+, Sx-LDH exhibits superior selectivity for UO22+, over previously reported sorbents. Under low U concentrations, (S4)2- coordinates to UO22+ forming anionic complexes retaining in the LDH gallery. At high U concentrations, (S4)2- binds to UO22+ to generate neutral UO2S4 salts outside the gallery, with NO3- entering the interlayer to form NO3-LDH. In the presence of high Cl- concentration, Cl- preferentially replaces [S4]2- and intercalates into LDH. Detailed comparison of U removal efficiency of Sx-LDH with various known sorbents is reported. The excellent uranium adsorption ability along with the environmentally safe, low-cost constituents points to the high potential of Sx-LDH materials for selective uranium capture.
AB - There is a need to develop highly selective and efficient materials for capturing uranium (normally as UO22+) from nuclear waste and from seawater. We demonstrate the promising adsorption performance of Sx-LDH composites (LDH is Mg/Al layered double hydroxide, [Sx]2- is polysulfide with x = 2, 4) for uranyl ions from a variety of aqueous solutions including seawater. We report high removal capacities (qm = 330 mg/g), large KdU values (104-106 mL/g at 1-300 ppm U concentration), and high % removals (>95% at 1-100 ppm, or ∼80% for ppb level seawater) for UO22+ species. The Sx-LDHs are exceptionally efficient for selectively and rapidly capturing UO22+ both at high (ppm) and trace (ppb) quantities from the U-containing water including seawater. The maximum adsorption coeffcient value KdU of 3.4 × 106 mL/g (using a V/m ratio of 1000 mL/g) observed is among the highest reported for U adsorbents. In the presence of very high concentrations of competitive ions such as Ca2+/Na+, Sx-LDH exhibits superior selectivity for UO22+, over previously reported sorbents. Under low U concentrations, (S4)2- coordinates to UO22+ forming anionic complexes retaining in the LDH gallery. At high U concentrations, (S4)2- binds to UO22+ to generate neutral UO2S4 salts outside the gallery, with NO3- entering the interlayer to form NO3-LDH. In the presence of high Cl- concentration, Cl- preferentially replaces [S4]2- and intercalates into LDH. Detailed comparison of U removal efficiency of Sx-LDH with various known sorbents is reported. The excellent uranium adsorption ability along with the environmentally safe, low-cost constituents points to the high potential of Sx-LDH materials for selective uranium capture.
UR - http://www.scopus.com/inward/record.url?scp=84925238697&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84925238697&partnerID=8YFLogxK
U2 - 10.1021/jacs.5b00762
DO - 10.1021/jacs.5b00762
M3 - Article
AN - SCOPUS:84925238697
VL - 137
SP - 3670
EP - 3677
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
SN - 0002-7863
IS - 10
ER -