Uranium(III) chloride

Uranium(III) chloride
Names
	IUPAC name Uranium(III) chloride
	Other names Uranium chloride; Uranium trichloride; Hypouranous chloride
Identifiers
CAS Number	10025-93-1 ;
3D model (JSmol)	Interactive image;
ChemSpider	146484 ;
PubChem CID	167444;
UNII	1SW3X68G1K ;
CompTox Dashboard (EPA)	DTXSID40894889 ;
	InChI InChI=1S/3ClH.U/h31H;/q;;;+3/p-3 Key: SAWLVFKYPSYVBL-UHFFFAOYSA-K ; InChI=1/3ClH.U/h31H;/q;;;+3/p-3 Key: SAWLVFKYPSYVBL-DFZHHIFOAG;
	SMILES Cl[U](Cl)Cl;
Properties
Chemical formula	UCl3
Appearance	Green crystalline solid
Density	5.500 g/cm3, liquid
Melting point	837 °C (1,539 °F; 1,110 K)
Boiling point	1,657 °C (3,015 °F; 1,930 K)
Solubility in water	Soluble
Structure
Hybridisation	Tricapped trigonal prismatic
Hazards
Flash point	Non-flammable
Autoignition; temperature	Non-flammable
Related compounds
Related compounds	Uranium(IV) chloride,; Uranium(V) chloride,; Uranium(VI) chloride
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). verify (what is ?) Infobox references

Uranium(III) chloride, UCl₃, is a water soluble salt of uranium. UCl₃ is used mostly to reprocess spent nuclear fuel. Uranium(III) chloride is synthesized in various ways from uranium(IV) chloride; however, UCl₃ is less stable than UCl₄.

Preparation

There are two ways to synthesize uranium(III) chloride. The following processes describe how to produce uranium(III) chloride.

(1) In a mixture of NaCl-KCl at 670–710 °C, add uranium tetrachloride with uranium metal.

3UCl₄ + U → 4UCl₃^[1]

(2) Heat uranium(IV) chloride in hydrogen gas.

2UCl₄ + H₂ → 2UCl₃ + 2HCl^[2]

Properties

In solid uranium(III) chloride each uranium atom has nine chlorine atoms as near neighbours, at approximately the same distance, in a tricapped trigonal prismatic configuration.^[3]

Uranium(III) chloride is a green crystalline solid at room temperature. UCl₃ melts at 837 °C and boils at 1657 °C. Uranium(III) chloride has a density of 5500 kg/m³ or 5.500 g/cm³.

Its composition by weight:

Chlorine: 30.84%

Uranium: 69.16%

Its formal oxidative states:

Chlorine: −1

Uranium: +3

This salt is very soluble in water and is also very hygroscopic. UCl₃ is more stable in a solution of hydrochloric acid.^[4]

Uses

Reagent

Uranium(III) chloride is used in reactions with tetrahydrofuran (THF) and sodium methylcyclopentadiene to prepare various uranium metallocene complexes.^[5]

Catalyst

Uranium(III) chloride is used as a catalyst during reactions between lithium aluminium hydride (LiAlH₄) and olefins to produce alkyl aluminate compounds.^[6]

Molten form

The molten form of uranium(III) chloride is a typical compound in pyrochemical processes as it is important in the reprocessing of spent nuclear fuels.^[7] UCl₃ is usually the form that uranium takes as spent fuel in electrorefining processes.^[7]^[8]

Hydrates

There are three hydrates of uranium(III) chloride:

UCl₃^.2H₂O^.2CH₃CN
UCl₃^.6H₂O
UCl₃^.7H₂O

Each are synthesized by the reduction of uranium(IV) chloride in methylcyanide (acetonitrile), with specific amounts of water and propionic acid.^[9]

Precautions

While there are no long-term data on the toxic effects thas UCl₃, it is important to minimize exposure to this compound when possible.

Similar to other uranium compounds that are soluble in water, UCl₃ is likely absorbed into the blood through the alveolar pockets of the lungs within days of exposure. Exposure to uranium(III) chloride leads to toxicity of the renal system.^[10]

References

^ Serrano, K.; Taxil, P.; Dugne, O.; Bouvet, S.; Puech, E. J. Nucl. Mater. 2000, 282, 137–145.
^ Remsen, Ira. Inorganic Chemistry. New York: Henry Holt and Company, 1890.
^ Wells A.F. (1984) Structural Inorganic Chemistry 5th edition Oxford Science Publications ISBN 0-19-855370-6
^ Comey, Arthur M.; Hahn, Dorothy A. A Dictionary of Chemical Solubilities: Inorganic. New York: The MacMillan Company, 1921.
^ Brenna, J.G.; Anderson, R.A.; Zalkin, A. Inorg. Chem. 1986, 25, 1756–1760.
^ Le Marechal, J.F.; Ephritikhine, M.; Folcher, G. J. Organomet. Chem. 1986, 309, C1–C3.
^ ^a ^b Okamoto, Y.; Madden, P.; Minato, K. J. Nucl. Mater. 2005, 344, 109–114.
^ Okamoto, Y.; Kobayashi, F.; Ogawa, T. J. Alloys Compd. 1998, 271, 355–358.
^ Mech, A.; Karbowick, M.; Lis, T. Polyhedron. 2006, 25, 2083–2092.
^ Bertell, Rosalie. "Gulf War Veterans and Depleted Uranium." May 1999. Available: http://ccnr.org/du_hague.html

External links

Uranium(III) chloride information at Webelements
Uranium(III) chloride International Bio-Analytical Industries, Inc.
Depleted Uranium: All the Questions about DU and Gulf War Syndrome are Not Yet Answered

[1] Serrano, K.; Taxil, P.; Dugne, O.; Bouvet, S.; Puech, E. J. Nucl. Mater. 2000, 282, 137–145.

[2] Remsen, Ira. Inorganic Chemistry. New York: Henry Holt and Company, 1890.

[3] Wells A.F. (1984) Structural Inorganic Chemistry 5th edition Oxford Science Publications ISBN 0-19-855370-6

[4] Comey, Arthur M.; Hahn, Dorothy A. A Dictionary of Chemical Solubilities: Inorganic. New York: The MacMillan Company, 1921.

[5] Brenna, J.G.; Anderson, R.A.; Zalkin, A. Inorg. Chem. 1986, 25, 1756–1760.

[6] Le Marechal, J.F.; Ephritikhine, M.; Folcher, G. J. Organomet. Chem. 1986, 309, C1–C3.

[okamoto1-7] Okamoto, Y.; Madden, P.; Minato, K. J. Nucl. Mater. 2005, 344, 109–114.

[8] Okamoto, Y.; Kobayashi, F.; Ogawa, T. J. Alloys Compd. 1998, 271, 355–358.

[9] Mech, A.; Karbowick, M.; Lis, T. Polyhedron. 2006, 25, 2083–2092.

[10] Bertell, Rosalie. "Gulf War Veterans and Depleted Uranium." May 1999. Available: http://ccnr.org/du_hague.html

[1]

[2]

[3]

[4]

[5]

[6]

[7]

[8]

[9]

[10]