Abstract
In the scheme of spent fuel reprocessing by using sulfides, selective sulfurization of rare-earths in the fuel is considered followed by either magnetic separation or selective leaching of rare-earth sulfides from uranium oxides such as UO2. In this paper, sulfurization behavior of rare-earth oxides was investigated by XRD and TG methods in the presence of CS2. From the results of thermogravimetric study the sulfurization of europium proceeds as follows; sulfurization from Eu2O3 to Eu3S4 occurs at ca. 400 °C, then the Eu3S4 decomposes to EuS via non-stoichiometric sulfides at temperatures between 450 and 700 °C. From the results of thermogravimetry for Nd2O3, it was found that the weight curve showed monotonic increase from ca. 600 to 1000 °C. At 1000 °C, the value of weight increase was close to that for the formation of Nd2S3 from Nd2O3. The XRD result of the 1000 °C product showed a formation of a single phase of Nd2S3 which is compared with the thermogravimetric result as well as our previous results. The selective sulfurization of rare-earths in the mixture of rare-earth and uranium oxides was discussed by both experimental results and thermodynamical consideration.
Original language | English |
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Pages (from-to) | 669-672 |
Number of pages | 4 |
Journal | Journal of Alloys and Compounds |
Volume | 451 |
Issue number | 1-2 |
DOIs | |
Publication status | Published - 2008 Feb 28 |
Keywords
- Carbon disulfide
- Europium
- Neodymium
- Sulfurization
- Thermogravimetry
ASJC Scopus subject areas
- Mechanics of Materials
- Mechanical Engineering
- Metals and Alloys
- Materials Chemistry