Thorium oxide dissolution in HNO3-HF mixture: kinetics and mechanism
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Marie Simonnet
Abstract
This paper is an attempt to find out thorium oxide dissolution mechanism in HNO3-HF mixture. In a previous paper, several parameters effects on thorium oxide dissolution have been described, with specific focus on hydrofluoric acid effect, which can lead to an increase of the dissolution rate if present in small amount, but precipitates as ThF4 at higher content. Based on this previous study, experimental data were fitted using several dissolution models in order to find out the best one. Finally, a revisited model based on literature and considering the ThF4 formation was proposed. It describes the main steps of dissolution and is able to fit the experimental data for a wide range of solution compositions. This point is crucial since it allows considering an extrapolation of the established model to not-yet-studied conditions.
Acknowledgements
The authors would like to thank ORANO and CNRS for financial support.
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©2019 Walter de Gruyter GmbH, Berlin/Boston
Artikel in diesem Heft
- Frontmatter
- Cross-section measurements and production of 72Se with medium to high energy protons using arsenic containing targets
- Thorium oxide dissolution in HNO3-HF mixture: kinetics and mechanism
- Highly efficient carbonaceous nanofiber/layered double hydroxide nanocomposites for removal of U(VI) from aqueous solutions
- Effect of solution acidity on the structure of amino acid-bearing uranyl compounds
- A novel method for the determination of uranium and free acidity in nuclear fuel process samples by extraction spectrophotometry
- Experimental investigation of photon attenuation parameters for different binary alloys
- Radiation protective characteristics of some selected tungstates
- New high temperature resistant heavy concretes for fast neutron and gamma radiation shielding
Artikel in diesem Heft
- Frontmatter
- Cross-section measurements and production of 72Se with medium to high energy protons using arsenic containing targets
- Thorium oxide dissolution in HNO3-HF mixture: kinetics and mechanism
- Highly efficient carbonaceous nanofiber/layered double hydroxide nanocomposites for removal of U(VI) from aqueous solutions
- Effect of solution acidity on the structure of amino acid-bearing uranyl compounds
- A novel method for the determination of uranium and free acidity in nuclear fuel process samples by extraction spectrophotometry
- Experimental investigation of photon attenuation parameters for different binary alloys
- Radiation protective characteristics of some selected tungstates
- New high temperature resistant heavy concretes for fast neutron and gamma radiation shielding
