Abstract
The ionic liquids, 1-butyl-3-methylimidazolium hexafluorophosphate [BMIM][PF6], N-ethylpyridiniumtrifluoroacetate [EtPy][CF3COO] and N-ethylpyridiniumtetrafluoroborate [EtPy][BF4], affected the reduction and precipitation of uranium by Clostridium sp. to a varying degree. Characterization of uranium association with the ionic liquids showed that uranium formed a monodentate complex with the anion BF4- and PF6- of [EtPy][BF4] and [BMIM][PF6], respectively; and a bidentate complex with carboxylate of [EtPy][CF3COO]. Bioreduction of U(VI) was influenced by the type of complex formed: monodentate complexes were readily reduced whereas the bidentate complex of U(VI) with [CF3COO] was recalcitrant. [EtPy][BF4] affected the rate and extent of precipitation of the reduced uranium; at higher concentration the reduced U(IV) remained in the solution phase. The results suggest that by tuning the properties of ionic liquids they may be valuable candidates for uranium biotreatment.
Original language | English (US) |
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Pages (from-to) | 752-756 |
Number of pages | 5 |
Journal | Bioresource Technology |
Volume | 136 |
DOIs | |
State | Published - May 2013 |
Externally published | Yes |
Keywords
- Bioreduction
- Clostridium sp.
- Ionic liquids
- Precipitation
- Uranium
ASJC Scopus subject areas
- Bioengineering
- Environmental Engineering
- Renewable Energy, Sustainability and the Environment
- Waste Management and Disposal