Elution of Uranium and Transition Metals from Amidoxime-Based
Polymer Adsorbents for Sequestering Uranium from Seawater
Horng-Bin Pan
Li-Jung Kuo
Chien M. Wai
Naomi Miyamoto
Ruma Joshi
Jordana
R. Wood
Jonathan E. Strivens
Christopher J. Janke
Yatsandra Oyola
Sadananda Das
Richard T. Mayes
Gary A. Gill
10.1021/acs.iecr.5b03307.s001
https://acs.figshare.com/articles/journal_contribution/Elution_of_Uranium_and_Transition_Metals_from_Amidoxime_Based_Polymer_Adsorbents_for_Sequestering_Uranium_from_Seawater/2104636
High-surface-area amidoxime and carboxylic
acid grafted polymer
adsorbents developed at Oak Ridge National Laboratory were tested
for sequestering uranium in a flowing seawater flume system at the
PNNL-Marine Sciences Laboratory. FTIR spectra indicate that a KOH
conditioning process is necessary to remove the proton from the carboxylic
acid and make the sorbent effective for sequestering uranium from
seawater. The alkaline conditioning process also converts the amidoxime
groups to carboxylate groups in the adsorbent. Both Na<sub>2</sub>CO<sub>3</sub>–H<sub>2</sub>O<sub>2</sub> and hydrochloric
acid elution methods can remove ∼95% of the uranium sequestered
by the adsorbent after 42 days of exposure in real seawater. The Na<sub>2</sub>CO<sub>3</sub>–H<sub>2</sub>O<sub>2</sub> elution method
is more selective for uranium than conventional acid elution. Iron
and vanadium are the two major transition metals competing with uranium
for adsorption to the amidoxime-based adsorbents in real seawater.
Tiron (4,5-dihydroxy-1,3-benzenedisulfonic acid disodium salt, 1 M)
can remove iron from the adsorbent very effectively at pH around 7.
The coordination between vanadium(V) and amidoxime is also discussed
based on our <sup>51</sup>V NMR data.
2015-11-30 00:00:00
Oak Ridge National Laboratory
51 V NMR data
carboxylic acid
hydrochloric acid elution methods
FTIR
CO
KOH conditioning process
seawater flume system
Uranium
amidoxime
sequestering uranium
adsorbent
vanadium