Uranyl and Arsenate Cosorption on Aluminum Oxide Surface
Abstract
In this study, we examined the effects of simultaneous adsorption of aqueous arsenate and uranyl onto aluminum oxide over a range of pH and concentration conditions. Arsenate was used as a chemical analog for phosphate, and offers advantages for characterization via X-ray absorption spectroscopy. By combining batch experiments, speciation calculations, X-ray absorption spectroscopy, and X-ray diffraction, we investigated the uptake behavior of uranyl, as well as the local and long-range structure of the final sorption products. In the presence of arsenate, uranyl sorption was greatly enhanced in the acidic pH range, and the amount of enhancement is positively correlated to the initial arsenate and uranyl concentrations. At pH 4-6, U L{sub III-} and As K-edge EXAFS results suggest the formation of surface-sorbed uranyl and arsenate species as well as uranyl arsenate surface precipitate(s) that have a structure similar to tr{umlt o}gerite. Uranyl polymeric species or oxyhydroxide precipitate(s) become more important with increasing pH values. Our results provide the basis for predictive models of the uptake of uranyl by aluminum oxide in the presence of arsenate and (by analogy) phosphate, which can be especially important for understanding phosphate-based uranium remediation systems.
- Authors:
- Publication Date:
- Research Org.:
- Brookhaven National Lab. (BNL), Upton, NY (United States). National Synchrotron Light Source
- Sponsoring Org.:
- Doe - Office Of Science
- OSTI Identifier:
- 980669
- Report Number(s):
- BNL-93587-2010-JA
Journal ID: ISSN 0016-7037; GCACAK; TRN: US201015%%2054
- DOE Contract Number:
- DE-AC02-98CH10886
- Resource Type:
- Journal Article
- Journal Name:
- Geochimica et Cosmochimica Acta
- Additional Journal Information:
- Journal Volume: 73; Journal Issue: 10; Journal ID: ISSN 0016-7037
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 36 MATERIALS SCIENCE; ABSORPTION SPECTROSCOPY; ADSORPTION; ALUMINIUM; ARSENATES; BEHAVIOR; OXIDES; PH VALUE; RANGE; SORPTION; SURFACES; UPTAKE; URANIUM; X-RAY DIFFRACTION; national synchrotron light source
Citation Formats
Tang, Y, and Reeder, R. Uranyl and Arsenate Cosorption on Aluminum Oxide Surface. United States: N. p., 2009.
Web. doi:10.1016/j.gca.2009.02.003.
Tang, Y, & Reeder, R. Uranyl and Arsenate Cosorption on Aluminum Oxide Surface. United States. https://doi.org/10.1016/j.gca.2009.02.003
Tang, Y, and Reeder, R. 2009.
"Uranyl and Arsenate Cosorption on Aluminum Oxide Surface". United States. https://doi.org/10.1016/j.gca.2009.02.003.
@article{osti_980669,
title = {Uranyl and Arsenate Cosorption on Aluminum Oxide Surface},
author = {Tang, Y and Reeder, R},
abstractNote = {In this study, we examined the effects of simultaneous adsorption of aqueous arsenate and uranyl onto aluminum oxide over a range of pH and concentration conditions. Arsenate was used as a chemical analog for phosphate, and offers advantages for characterization via X-ray absorption spectroscopy. By combining batch experiments, speciation calculations, X-ray absorption spectroscopy, and X-ray diffraction, we investigated the uptake behavior of uranyl, as well as the local and long-range structure of the final sorption products. In the presence of arsenate, uranyl sorption was greatly enhanced in the acidic pH range, and the amount of enhancement is positively correlated to the initial arsenate and uranyl concentrations. At pH 4-6, U L{sub III-} and As K-edge EXAFS results suggest the formation of surface-sorbed uranyl and arsenate species as well as uranyl arsenate surface precipitate(s) that have a structure similar to tr{umlt o}gerite. Uranyl polymeric species or oxyhydroxide precipitate(s) become more important with increasing pH values. Our results provide the basis for predictive models of the uptake of uranyl by aluminum oxide in the presence of arsenate and (by analogy) phosphate, which can be especially important for understanding phosphate-based uranium remediation systems.},
doi = {10.1016/j.gca.2009.02.003},
url = {https://www.osti.gov/biblio/980669},
journal = {Geochimica et Cosmochimica Acta},
issn = {0016-7037},
number = 10,
volume = 73,
place = {United States},
year = {Thu Jan 01 00:00:00 EST 2009},
month = {Thu Jan 01 00:00:00 EST 2009}
}