bei Google ScholarTitelangaben
Bachmaf, Samer ; Planer-Friedrich, Britta ; Merkel, Broder J.:
Effect of sulphate, carbonate, and phosphate on the uranium(VI) sorption behaviour onto bentonite.
In: Radiochimica Acta.
Bd. 96
(2008)
Heft 6
.
- S. 359-366.
ISSN 0033-8230
DOI: https://doi.org/10.1524/ract.2008.1496
Abstract
Batch experiments were conducted to study the uranium U(VI) sorption onto bentonite as a function of pH (3 to 8), and initial U(VI) concentrations (5×10−6 and 5×10−5 M) in the presence and absence of sulfate, carbonate, and phosphate. Uranium sorption onto bentonite depended on the initial U(VI) concentration with a stronger sorption at lower concentrations and was high over a wide range of pH in the absence of complexing ligands. In the presence of 0.005M sulfate, U(VI) sorption was reduced at low pH values due to the competition between SO42− and the uranyl ion for sorption sites on the bentonite surface, or the formation of uranyl-sulfate complexes. In the presence of 0.003M carbonate, U(VI) sorption decreased sharply at a pH above 7, because of the formation of negatively charged uranyl-carbonate complexes, which are weakly adsorbed onto the bentonite. Uranium sorption onto bentonite was greatly enhanced in the presence of 0.003M phosphate. Kinetic batch experiments carried out for 5×10−5 M U(VI) at pH values of 3, 5, and 8 revealed that the sorption rate was generally rapid over the first 10 min of the experiments, then slowed down appreciably after 1 to 24 h. Sulfate had little effect on the kinetics of U(VI) sorption; both in the absence and presence of sulfate, sorption equilibrium was attained after 4 h. In the presence of carbonate, attainment of sorption equilibrium required more time than in its absence. The presence of 0.003M phosphate reduced the time required to reach sorption equilibrium across a wide range of pH compared to phosphate-free systems.
Weitere Angaben
| Publikationsform: | Artikel in einer Zeitschrift |
|---|---|
| Begutachteter Beitrag: | Ja |
| Zusätzliche Informationen: | BAYCEER80730 |
| Institutionen der Universität: | Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften > Fachgruppe Geowissenschaften > Professur Umweltgeochemie Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften > Fachgruppe Geowissenschaften > Professur Umweltgeochemie > Professur Umweltgeochemie - Univ.-Prof. Dr. Britta Planer-Friedrich Fakultäten Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften > Fachgruppe Geowissenschaften |
| Titel an der UBT entstanden: | Ja |
| Themengebiete aus DDC: | 500 Naturwissenschaften und Mathematik |
| Eingestellt am: | 05 Mai 2015 12:10 |
| Letzte Änderung: | 09 Jul 2020 06:24 |
| URI: | https://eref.uni-bayreuth.de/id/eprint/12819 |