Abstract
The dissolution rate and solubility of NaBiO 3 have been investigated in nitric acid systems ranging from 4 to 6 M HNO 3 and were found to be 58-76 μg/cm 2 ·d and 490-830 mM, respectively. The presence of 50 mM U(VI) drastically increased the solubility to 540-1200 mM, while rates of dissolution were relatively unchanged. The solubility of NaBiO 3 increased with an increase in U(VI) concentrations at 4 M HNO 3 , with log-log analysis indicating a one-to-one complex between Bi and U and infrared spectroscopic evidence monitoring uranyl stretching, suggesting complex formation. Absorbance spectra were obtained experimentally and computationally with an absorbance band in the range of 450-600 nm that has been attributed to Bi(V). The ingrowth and decay of Bi(V) in solution was also studied as a function of mass of solid NaBiO 3 present, acidity, and temperature. The activation energies of dissolution and decomposition were calculated to be 39 ± 4 and 61 ± 6 kJ/mol, respectively. These results indicate that dissolution of NaBiO 3 into the respective Na + and BiO 3 - occurs prior to undergoing reduction, a process which conventionally has been believed to occur in the reverse order.
| Original language | English |
|---|---|
| Pages (from-to) | 15341-15349 |
| Number of pages | 9 |
| Journal | Inorganic Chemistry |
| Volume | 57 |
| Issue number | 24 |
| DOIs | |
| State | Published - Dec 17 2018 |
| Externally published | Yes |
Funding
This submitted report has been authored by Texas A&M University, under award no. DE-NE0008653 with the U.S. Department of Energy. The publisher, by accepting the article for publication, acknowledges that the United States Government retains a nonexclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for the United States Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (http://energy. gov/downloads/doe-public-access-plan). This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. This work was sponsored by the Nuclear Energy University Program, Office of Nuclear Energy, U.S. Department of Energy, under award no. DENE0008653. We want to acknowledge Dr. Luis H. Ortega of the Fuel Cycle and Materials Laboratory in the Department of Nuclear Engineering at Texas A&M University who aided in obtaining the SEM images for the particle size determination and EDS measurements. We also want to thank Dr. Lisa M. Pereź of the Laboratory for Molecular Simulation for computational resources and the Texas A&M University Laboratory for Synthetic−Biologic Interactions for use of the ATR−FTIR.