Uranyl nitrate
Structural formula | ||||||||||
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General | ||||||||||
Surname | Uranyl nitrate | |||||||||
Molecular formula |
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Brief description |
lemon-yellow, yellow-green fluorescent solid |
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External identifiers / databases | ||||||||||
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properties | ||||||||||
Molar mass | ||||||||||
Physical state |
firmly |
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density |
2.81 g cm −3 (13 ° C) |
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Melting point |
Decomposition> 100 ° C |
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solubility |
good in water (550 g l −1 at 20 ° C, hexahydrate) |
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Hazard and safety information | ||||||||||
Radioactive |
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As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . |
Uranyl nitrate (UO 2 (NO 3 ) 2 ) is a water-soluble yellow uranium salt . It can be obtained by reacting uranium salts with nitric acid .
properties
Uranyl nitrate dissolves very well in water, also in ethanol , acetone and ether , but not in benzene , toluene or chloroform . The yellow-green crystals of uranyl nitrate hexahydrate are triboluminescent . At higher temperatures it decomposes to uranium trioxide (UO 3 ).
use
Together with uranyl acetate , uranyl nitrate is used for negative contrasting in electron microscopes .
During reprocessing , uranyl nitrate is produced when the spent nuclear fuel (mostly UO 2 ) or yellow cake is dissolved in nitric acid . It is then converted in further steps to uranium hexafluoride , which is used for isotope separation and for the production of enriched uranium.
safety instructions
Uranyl nitrate is an oxidizing and highly toxic compound. In addition, there is a risk of accumulation in the human body, especially in the liver and kidneys . It is also toxic to aquatic organisms and can cause long-term damage to the aquatic world. Like all uranium compounds, it is radioactive . The activity depends on the isotopic composition of the uranium. In addition, uranyl nitrate has a fire-promoting effect and can lead to explosions when heated in contact with oxidizable substances.
Individual evidence
- ↑ a b c d e Entry on uranyl nitrate in the GESTIS substance database of the IFA , accessed on January 15, 2017(JavaScript required) .
- ↑ Not explicitly listed in Regulation (EC) No. 1272/2008 (CLP) , but with the specified labeling it falls under the group entry uranium compounds with the exception of those specified elsewhere in this Annex in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA) , accessed on February 1, 2016. Manufacturers or distributors can expand the harmonized classification and labeling .
- ↑ The hazards emanating from radioactivity do not belong to the properties to be classified according to the GHS labeling.
- ↑ DE Roberts, TS Modise: “Laser removal of loose uranium compound contamination from metal surfaces”, in: Applied Surface Science , 2007 , 253 , pp. 5258-5267; doi: 10.1016 / j.apsusc.2006.11.050 .
literature
- Ingmar Grenthe, Janusz Drożdżynński, Takeo Fujino, Edgar C. Buck, Thomas E. Albrecht-Schmitt, Stephen F. Wolf: Uranium , in: Lester R. Morss, Norman M. Edelstein, Jean Fuger (eds.): The Chemistry of the Actinide and Transactinide Elements , Springer, Dordrecht 2006; ISBN 1-4020-3555-1 , pp. 253-698; doi: 10.1007 / 1-4020-3598-5_5 .