Uranium(III) hydride: Difference between revisions

Uranium(III) hydride
Names
	Other names Uranium(III) hydride; Uranium trihydride; Hypouranous hydride
Identifiers
CAS Number	13598-56-6 ;
3D model (JSmol)	Interactive image; Interactive image;
ChemSpider	25935465 ;
PubChem CID	71308292;
CompTox Dashboard (EPA)	DTXSID1042522 ;
	InChI InChI=1S/U.3H Key: XOTGRWARRARRKM-UHFFFAOYSA-N ;
	SMILES [UH3]; [H-].[H-].[H-].[U+3];
Properties
Chemical formula	UH; 3
Molar mass	241.05273 g mol−1
Appearance	brownish grey to brownish black pyrophoric powder
Density	10.95 g cm−3
Solubility in water	Reacts
Structure
Crystal structure	Cubic, cP32
Space group	Pm3n, No. 223
Lattice constant	a = 664.3 pm
Hazards
Flash point	Pyrophoric
Safety data sheet (SDS)	ibilabs.com
	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

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Uranium hydride, also called uranium trihydride (UH₃), is an inorganic compound and a hydride of uranium.

Properties

Uranium hydride is a highly toxic, brownish grey to brownish black pyrophoric powder or brittle solid. Its density at 20 °C is 10.95 g cm⁻³, much lower than that of uranium (19.1 g cm⁻³). It has a metallic conductivity, is slightly soluble in hydrochloric acid and decomposes in nitric acid.

Two crystal modifications of uranium hydride exist, both cubic: an α form that is obtained at low temperatures and a β form that is grown when the formation temperature is above 250 °C.^[5] After growth, both forms are metastable at room temperature and below, but the α form slowly converts to the β form upon heating to 100 °C.^[3] Both α- and β-UH₃ are ferromagnetic at temperatures below ~180 K. Above 180 K, they are paramagnetic.^[6]

Formation in uranium metal

Hydrogen gas reaction

Exposure of uranium metal to hydrogen leads to hydrogen embrittlement. Hydrogen diffuses through metal and forms a network of brittle hydride over the grain boundaries. Hydrogen can be removed and ductility renewed by annealing in vacuum.^[7]

Uranium metal heated to 250 to 300 °C (482 to 572 °F) reacts with hydrogen to form uranium hydride. Further heating to about 500 °C will reversibly remove the hydrogen. This property makes uranium hydrides convenient starting materials to create reactive uranium powder along with various uranium carbide, nitride, and halide compounds.^[5] The reversible reaction proceeds as follows:^[2]

2 U + 3 H₂ ⇌ 2 UH₃

Uranium hydride is not an interstitial compound, causing the metal to expand upon hydride formation. In its lattice, each uranium atom is surrounded by 6 other uranium atoms and 12 atoms of hydrogen; each hydrogen atom occupies a large tetrahedral hole in the lattice.^[8] The density of hydrogen in uranium hydride is approximately the same as in liquid water or in liquid hydrogen.^[9] The U-H-U linkage through a hydrogen atom is present in the structure.^[10]

Water reaction

Uranium hydride forms when uranium metal (e.g. in Magnox fuel with corroded cladding) becomes exposed to water or steam, with uranium dioxide as byproduct:^[8]

7 U + 6 H₂O → 3 UO₂ + 4 UH₃

The resulting uranium hydride is pyrophoric; if the metal (e.g. a damaged fuel rod) is exposed to air afterwards, excessive heat may be generated and the bulk uranium metal itself can ignite.^[11] Hydride-contaminated uranium can be passivated by exposure to a gaseous mixture of 98% helium with 2% oxygen.^[12] Condensed moisture on uranium metal promotes formation of hydrogen and uranium hydride; a pyrophoric surface may be formed in absence of oxygen.^[13] This poses a problem with underwater storage of very special spent nuclear fuel in spent fuel ponds (nuclear fuel from commercial nuclear plants does NOT contain any uranium metal). Depending on the size and distribution on the hydride particles, self-ignition can occur after an indeterminate length of exposure to air.^[14] Such exposure poses risk of self-ignition of fuel debris in radioactive waste storage vaults.^[15]

Uranium hydride exposed to water evolves hydrogen. In contact with strong oxidizers this may cause fire and explosions. Contact with halocarbons may cause a violent reaction.^[16]

Other chemical reactions

Polystyrene-impregnated uranium hydride powder is non-pyrophoric and can be pressed, however its hydrogen-carbon ratio is unfavorable. Hydrogenated polystyrene was introduced in 1944 instead.^[17]

Uranium deuteride is said to be usable for design of some types of neutron initiators.

Uranium hydride enriched to about 5% uranium-235 is proposed as a combined nuclear fuel/neutron moderator for the Hydrogen Moderated Self-regulating Nuclear Power Module. According to the aforementioned patent application, the reactor design in question begins producing power when hydrogen gas at a sufficient temperature and pressure is admitted to the core (made up of granulated uranium metal) and reacts with the uranium metal to form uranium hydride.^[18] Uranium hydride is both a nuclear fuel and a neutron moderator; apparently it, like other neutron moderators, will slow neutrons sufficiently to allow for fission reactions to take place; the uranium-235 atoms within the hydride also serve as the nuclear fuel. Once the nuclear reaction has started, it will continue until it reaches a certain temperature, approximately 800 °C (1,500 °F), where, due to the chemical properties of uranium hydride, it chemically decomposes and turns into hydrogen gas and uranium metal. The loss of neutron moderation due to the chemical decomposition of the uranium hydride will consequently slow — and eventually halt — the reaction. When temperature returns to an acceptable level, the hydrogen will again combine with the uranium metal, forming uranium hydride, restoring moderation and the nuclear reaction will start again.^[18]

On heating with diborane, uranium hydride produces uranium boride.^[19] With bromine at 300 °C, uranium(IV) bromide is produced. With chlorine at 250 °C, uranium(IV) chloride is produced. Hydrogen fluoride at 20 °C produces uranium(IV) fluoride. Hydrogen chloride at 300 °C produces uranium(III) chloride. Hydrogen bromide at 300 °C produces uranium(III) bromide. Hydrogen iodide at 300 °C produces uranium(III) iodide. Ammonia at 250 °C produces uranium(III) nitride. Hydrogen sulfide at 400 °C produces uranium(IV) sulfide. Oxygen at 20 °C produces triuranium octoxide. Water at 350 °C produces uranium dioxide.^[20]

Uranium hydride ion may interfere with some mass spectrometry measurements, appearing as a peak at mass 239, creating false increase of signal for plutonium-239.^[21]

History

Uranium hydride slugs were used in the "tickling the dragon's tail" series of experiments to determine the critical mass of uranium.^[22]

Uranium hydride and uranium deuteride were suggested as a fissile material for a uranium hydride bomb. The tests with uranium hydride and uranium deuteride during Operation Upshot–Knothole were disappointing, however. During the early phases of the Manhattan Project, in 1943, uranium hydride was investigated as a promising bomb material; it was abandoned by early 1944 as it turned out that such a design would be inefficient.^[23]

Applications

Hydrogen, deuterium, and tritium can be purified by reacting with uranium, then thermally decomposing the resulting hydride/deuteride/tritide.^[24] Extremely pure hydrogen has been prepared from beds of uranium hydride for decades.^[25] Heating uranium hydride is a convenient way to introduce hydrogen into a vacuum system.^[26]

The swelling and pulverization at uranium hydride synthesis can be used for preparation of very fine uranium metal, if the powdered hydride is thermally decomposed.

Uranium hydride can be used for isotope separation of hydrogen, preparing uranium metal powder, and as a reducing agent.

Uranium tritide (UT) is used for the safe and efficient storage of tritium, since gaseous tritium is harder to contain and work with. UT is formed by combining tritium and uranium at room temperature. The tritium can be later extracted by heating the UT. Tritium and its decay product ³He are extracted at different temperatures.^[27]

References

^ Carl L. Yaws (2008). Thermophysical properties of chemicals and hydrocarbons. William Andrew. pp. 307–. ISBN 978-0-8155-1596-8. Retrieved 11 October 2011.
^ ^a ^b Egon Wiberg; Nils Wiberg; Arnold Frederick Holleman (2001). Inorganic chemistry. Academic Press. pp. 239–. ISBN 978-0-12-352651-9. Retrieved 11 October 2011.
^ ^a ^b Gerd Meyer; Lester R. Morss (1991). Synthesis of lanthanide and actinide compounds. Springer. pp. 44–. ISBN 978-0-7923-1018-1. Retrieved 11 October 2011.
^ Bartscher W.; Boeuf A.; Caciuffo R.; Fournier J.M.; Kuhs W.F.; Rebizant J.; Rustichelli F (1985). "Neutron diffraction study of b-UD3 AND b-UH3". Solid State Commun. 53: 423–426. doi:10.1016/0038-1098(85)91000-2.
^ ^a ^b Seaborg, Glenn T. (1968). "Uranium". The Encyclopedia of the Chemical Elements. Skokie, Illinois: Reinhold Book Corporation. p. 782. LCCCN 68-29938.
^ K. H. J. Buschow (2005). Concise encyclopedia of magnetic and superconducting materials. Elsevier. pp. 901–. ISBN 978-0-08-044586-1. Retrieved 11 October 2011.
^ I. N. Toumanov (2003). Plasma and high frequency processes for obtaining and processing materials in the nuclear fuel cycle. Nova Publishers. p. 232. ISBN 1-59033-009-9. Retrieved 2010-02-07.
^ ^a ^b Amit Arora (2005). Text Book Of Inorganic Chemistry. Discovery Publishing House. p. 789. ISBN 81-8356-013-X. Retrieved 2010-02-07.
^ Peter Gevorkian (2009). Alternative Energy Systems in Building Design (GreenSource Books). McGraw Hill Professional. p. 393. ISBN 978-0-07-162147-2. Retrieved 2010-02-07.
^ G. Singh (2007). Environmental Pollution. Discovery Publishing House. ISBN 978-81-8356-241-6. Retrieved 2010-02-07.
^ "Rust never sleeps". Bulletin of the Atomic Scientists. 50 (5): 49. 1994. Retrieved 2010-02-07.
^ "EMSP". Teton.if.uidaho.edu. Archived from the original on 2009-09-30. Retrieved 2010-02-07.
^ OECD Nuclear Energy Agency (2006). Advanced nuclear fuel cycles and radioactive waste management. OECD Publishing. p. 176. ISBN 92-64-02485-9. Retrieved 2010-02-07.
^ Abir Al-Tabbaa; J. A. Stegemann (2005). Stabilisation/Solidification Treatment and Remediation: Proceedings of the International Conference on Stabilisation/Solidification Treatment and Remediation, 12–13 April 2005, Cambridge, UK. Taylor & Francis. p. 197. ISBN 0-415-37460-X. Retrieved 2010-02-07.
^ International Conference on Nuclear Decom 2001: ensuring safe, secure and successful decommissioning: 16–18 October 2001 Commonwealth Conference and Events Centre, London UK, Issue 8. John Wiley and Sons. 2001. p. 278. ISBN 1-86058-329-6. Retrieved 2010-02-07.
^ "Uranium & Insoluble Compounds". Osha.gov. Archived from the original on 2010-03-22. Retrieved 2010-02-07.
^ Lillian Hoddeson; et al. (2004). Critical Assembly: A Technical History of Los Alamos During the Oppenheimer Years, 1943–1945. Cambridge University Press. p. 211. ISBN 0-521-54117-4. Retrieved 2010-02-07.
^ ^a ^b Peterson, Otis G. (2008-03-20). "Patent Application 11/804450: Self-regulating nuclear power module". United States Patent Application Publication. United States Patent and Trademark Office, Federal Government of the United States, Washington, DC, USA. Retrieved 2009-09-05.
^ Harry Julius Emeléus (1974). Advances in inorganic chemistry and radiochemistry. Vol. 16. Academic Press. p. 235. ISBN 0-12-023616-8. Retrieved 2010-02-07.
^ Simon Cotton (2006). Lanthanide and actinide chemistry. John Wiley and Sons. p. 170. ISBN 0-470-01006-1. Retrieved 2010-02-07.
^ Kenton James Moody; Ian D. Hutcheon; Patrick M. Grant (2005). Nuclear forensic analysis. CRC Press. p. 243. ISBN 0-8493-1513-1. Retrieved 2010-02-07.
^ "Photo – Tickling the Dragon's Tail". Mphpa.org. 2005-08-03. Archived from the original on 2010-02-18. Retrieved 2010-02-07.
^ Moore, Mike (July 1994). "Lying well". Bulletin of the Atomic Scientists. 50 (4): 2. Bibcode:1994BuAtS..50d...2M. doi:10.1080/00963402.1994.11456528. Retrieved 2010-02-07.
^ E. E. Shpil'rain (1987). Thermophysical properties of lithium hydride, deuteride, and tritide and of their solutions with lithium. Springer. p. 104. ISBN 0-88318-532-6. Retrieved 2010-02-07.
^ Yuda Yürüm (1995). Hydrogen energy system: production and utilization of hydrogen and future aspects. Springer. p. 264. ISBN 0-7923-3601-1. Retrieved 2010-02-07.
^ Fred Rosebury (1992). Handbook of electron tube and vacuum techniques. Springer. p. 121. ISBN 1-56396-121-0. Retrieved 2010-02-07.
^ "NIS - Tritium Uses" (PDF). NIS Nuclear Info. 2022. Retrieved 2024-12-12.

[1] Carl L. Yaws (2008). Thermophysical properties of chemicals and hydrocarbons. William Andrew. pp. 307–. ISBN 978-0-8155-1596-8. Retrieved 11 October 2011.

[wib-2] Egon Wiberg; Nils Wiberg; Arnold Frederick Holleman (2001). Inorganic chemistry. Academic Press. pp. 239–. ISBN 978-0-12-352651-9. Retrieved 11 October 2011.

[mor-3] Gerd Meyer; Lester R. Morss (1991). Synthesis of lanthanide and actinide compounds. Springer. pp. 44–. ISBN 978-0-7923-1018-1. Retrieved 11 October 2011.

[4] Bartscher W.; Boeuf A.; Caciuffo R.; Fournier J.M.; Kuhs W.F.; Rebizant J.; Rustichelli F (1985). "Neutron diffraction study of b-UD3 AND b-UH3". Solid State Commun. 53: 423–426. doi:10.1016/0038-1098(85)91000-2.

[EncyChem782-5] Seaborg, Glenn T. (1968). "Uranium". The Encyclopedia of the Chemical Elements. Skokie, Illinois: Reinhold Book Corporation. p. 782. LCCCN 68-29938.

[6] K. H. J. Buschow (2005). Concise encyclopedia of magnetic and superconducting materials. Elsevier. pp. 901–. ISBN 978-0-08-044586-1. Retrieved 11 October 2011.

[7] I. N. Toumanov (2003). Plasma and high frequency processes for obtaining and processing materials in the nuclear fuel cycle. Nova Publishers. p. 232. ISBN 1-59033-009-9. Retrieved 2010-02-07.

[google1-8] Amit Arora (2005). Text Book Of Inorganic Chemistry. Discovery Publishing House. p. 789. ISBN 81-8356-013-X. Retrieved 2010-02-07.

[9] Peter Gevorkian (2009). Alternative Energy Systems in Building Design (GreenSource Books). McGraw Hill Professional. p. 393. ISBN 978-0-07-162147-2. Retrieved 2010-02-07.

[10] G. Singh (2007). Environmental Pollution. Discovery Publishing House. ISBN 978-81-8356-241-6. Retrieved 2010-02-07.

[11] "Rust never sleeps". Bulletin of the Atomic Scientists. 50 (5): 49. 1994. Retrieved 2010-02-07.

[12] "EMSP". Teton.if.uidaho.edu. Archived from the original on 2009-09-30. Retrieved 2010-02-07.

[13] OECD Nuclear Energy Agency (2006). Advanced nuclear fuel cycles and radioactive waste management. OECD Publishing. p. 176. ISBN 92-64-02485-9. Retrieved 2010-02-07.

[14] Abir Al-Tabbaa; J. A. Stegemann (2005). Stabilisation/Solidification Treatment and Remediation: Proceedings of the International Conference on Stabilisation/Solidification Treatment and Remediation, 12–13 April 2005, Cambridge, UK. Taylor & Francis. p. 197. ISBN 0-415-37460-X. Retrieved 2010-02-07.

[15] International Conference on Nuclear Decom 2001: ensuring safe, secure and successful decommissioning: 16–18 October 2001 Commonwealth Conference and Events Centre, London UK, Issue 8. John Wiley and Sons. 2001. p. 278. ISBN 1-86058-329-6. Retrieved 2010-02-07.

[16] "Uranium & Insoluble Compounds". Osha.gov. Archived from the original on 2010-03-22. Retrieved 2010-02-07.

[critas-17] Lillian Hoddeson; et al. (2004). Critical Assembly: A Technical History of Los Alamos During the Oppenheimer Years, 1943–1945. Cambridge University Press. p. 211. ISBN 0-521-54117-4. Retrieved 2010-02-07.

[USPatApp11804450-18] Peterson, Otis G. (2008-03-20). "Patent Application 11/804450: Self-regulating nuclear power module". United States Patent Application Publication. United States Patent and Trademark Office, Federal Government of the United States, Washington, DC, USA. Retrieved 2009-09-05.

[19] Harry Julius Emeléus (1974). Advances in inorganic chemistry and radiochemistry. Vol. 16. Academic Press. p. 235. ISBN 0-12-023616-8. Retrieved 2010-02-07.

[20] Simon Cotton (2006). Lanthanide and actinide chemistry. John Wiley and Sons. p. 170. ISBN 0-470-01006-1. Retrieved 2010-02-07.

[21] Kenton James Moody; Ian D. Hutcheon; Patrick M. Grant (2005). Nuclear forensic analysis. CRC Press. p. 243. ISBN 0-8493-1513-1. Retrieved 2010-02-07.

[22] "Photo – Tickling the Dragon's Tail". Mphpa.org. 2005-08-03. Archived from the original on 2010-02-18. Retrieved 2010-02-07.

[23] Moore, Mike (July 1994). "Lying well". Bulletin of the Atomic Scientists. 50 (4): 2. Bibcode:1994BuAtS..50d...2M. doi:10.1080/00963402.1994.11456528. Retrieved 2010-02-07.

[24] E. E. Shpil'rain (1987). Thermophysical properties of lithium hydride, deuteride, and tritide and of their solutions with lithium. Springer. p. 104. ISBN 0-88318-532-6. Retrieved 2010-02-07.

[25] Yuda Yürüm (1995). Hydrogen energy system: production and utilization of hydrogen and future aspects. Springer. p. 264. ISBN 0-7923-3601-1. Retrieved 2010-02-07.

[26] Fred Rosebury (1992). Handbook of electron tube and vacuum techniques. Springer. p. 121. ISBN 1-56396-121-0. Retrieved 2010-02-07.

[27] "NIS - Tritium Uses" (PDF). NIS Nuclear Info. 2022. Retrieved 2024-12-12.

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@@ Line 1: / Line 1: @@
-{{about|UH<sub>3</sub>|the low temperature molecular compound |Uranium(IV) hydride}}
+{{about|UH<sub>3</sub>|the low temperature molecular compound UH<sub>4</sub>|Uranium(IV) hydride}}
 {{Chembox
 | Verifiedfields = changed
 | Watchedfields = changed
 | verifiedrevid = 470619917
-| OtherNames = Uranium(III) hydride<ref>{{cite book|author=Carl L. Yaws|title=Thermophysical properties of chemicals and hydrocarbons|url=https://books.google.com/books?id=31O4upzTHQwC&pg=PA307|accessdate=11 October 2011|year=2008|publisher=William Andrew|isbn=978-0-8155-1596-8|pages=307–}}</ref><br />
+| OtherNames = Uranium(III) hydride<ref>{{cite book|author=Carl L. Yaws|title=Thermophysical properties of chemicals and hydrocarbons|url=https://books.google.com/books?id=31O4upzTHQwC&pg=PA307|access-date=11 October 2011|year=2008|publisher=William Andrew|isbn=978-0-8155-1596-8|pages=307–}}</ref><br />
-Uranium trihydride<ref name=wib>{{cite book|author1=Egon Wiberg|author2=Nils Wiberg|author3=Arnold Frederick Holleman|title=Inorganic chemistry|url=https://books.google.com/books?id=Mtth5g59dEIC&pg=PA239|accessdate=11 October 2011|year=2001|publisher=Academic Press|isbn=978-0-12-352651-9|pages=239–}}</ref><ref name=mor>{{cite book|author1=Gerd Meyer|author2=Lester R. Morss|title=Synthesis of lanthanide and actinide compounds|url=https://books.google.com/books?id=bnS5elHL2w8C&pg=PA44|accessdate=11 October 2011|year=1991|publisher=Springer|isbn=978-0-7923-1018-1|pages=44–}}</ref><br />Hypouranous hydride
+Uranium trihydride<ref name=wib>{{cite book|author1=Egon Wiberg|author2=Nils Wiberg|author3=Arnold Frederick Holleman|title=Inorganic chemistry|url=https://books.google.com/books?id=Mtth5g59dEIC&pg=PA239|access-date=11 October 2011|year=2001|publisher=Academic Press|isbn=978-0-12-352651-9|pages=239–}}</ref><ref name=mor>{{cite book|author1=Gerd Meyer|author2=Lester R. Morss|title=Synthesis of lanthanide and actinide compounds|url=https://books.google.com/books?id=bnS5elHL2w8C&pg=PA44|access-date=11 October 2011|year=1991|publisher=Springer|isbn=978-0-7923-1018-1|pages=44–}}</ref><br />Hypouranous hydride
 |Section1={{Chembox Identifiers
 | CASNo = 13598-56-6
@@ Line 11: / Line 11: @@
 | ChemSpiderID = 25935465
 | ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
+| PubChem = 71308292
 | SMILES = [UH3]
 | SMILES1 = [H-].[H-].[H-].[U+3]
@@ Line 21: / Line 22: @@
 | Formula = {{Chem|UH|3}}
 | MolarMass = 241.05273 g mol<sup>−1</sup>
+| Appearance = brownish grey to brownish black [[pyrophoric]] powder
 | Density = 10.95 g cm<sup>−3</sup>
 | Solubility = Reacts
@@ Line 27: / Line 29: @@
 | CrystalStruct = Cubic, [[Pearson symbol|cP32]]
 | SpaceGroup = Pm{{overbar|3}}n, No. 223
-| LattConst_a = 664.3 pm<ref>{{cite journal|journal = Solid State Commun|year = 1985|volume = 53|pages = 423–426|title = Neutron diffraction study of b-UD3 AND b-UH3|authors = Bartscher W., Boeuf A., Caciuffo R., Fournier J.M., Kuhs W.F., Rebizant J., Rustichelli F|doi=10.1016/0038-1098(85)91000-2}}</ref>
+| LattConst_a = 664.3 pm<ref>{{cite journal|journal = Solid State Commun|year = 1985|volume = 53|pages = 423–426|title = Neutron diffraction study of b-UD3 AND b-UH3|author=Bartscher W. |author2=Boeuf A. |author3=Caciuffo R. |author4=Fournier J.M. |author5=Kuhs W.F. |author6=Rebizant J. |author7=Rustichelli F |doi=10.1016/0038-1098(85)91000-2}}</ref>
 }}
 |Section5={{Chembox Hazards
@@ Line 38: / Line 40: @@
 ==Properties==
-Uranium hydride is a highly toxic, brownish gray to brownish black [[pyrophoric]] powder or brittle solid. Its density at 20&nbsp;°C is 10.95, much lower than that of uranium (19.1). It has a metallic conductivity, is slightly soluble in [[hydrochloric acid]] and decomposes in [[nitric acid]].
+Uranium hydride is a highly toxic, brownish grey to brownish black [[pyrophoric]] powder or brittle solid. Its density at 20&nbsp;°C is 10.95 g cm<sup>−3</sup>, much lower than that of uranium (19.1 g cm<sup>−3</sup>). It has a metallic conductivity, is slightly soluble in [[hydrochloric acid]] and decomposes in [[nitric acid]].
-Two crystal modifications of uranium hydride exist, both cubic: an α form that is obtained at low temperatures and a β form that is grown when the formation temperature is above 250&nbsp;°C.<ref name="EncyChem782"/> After growth, both forms are metastable at room temperature and below, but the α form slowly converts to the β form upon heating to 100&nbsp;°C.<ref name=mor>{{cite book|author1=Gerd Meyer|author2=Lester R. Morss|title=Synthesis of lanthanide and actinide compounds|url=https://books.google.com/books?id=bnS5elHL2w8C&pg=PA44|accessdate=11 October 2011|year=1991|publisher=Springer|isbn=978-0-7923-1018-1|pages=44–}}</ref> Both α- and β-UH<sub>3</sub> are [[ferromagnetism|ferromagnetic]] at temperatures below ~180 K. Above 180 K, they are paramagnetic.<ref>{{cite book|author=K. H. J. Buschow|title=Concise encyclopedia of magnetic and superconducting materials|url=https://books.google.com/books?id=N9mvytGEBtwC&pg=PA901|accessdate=11 October 2011|year=2005|publisher=Elsevier|isbn=978-0-08-044586-1|pages=901–}}</ref>
+Two crystal modifications of uranium hydride exist, both cubic: an α form that is obtained at low temperatures and a β form that is grown when the formation temperature is above 250&nbsp;°C.<ref name="EncyChem782"/> After growth, both forms are metastable at room temperature and below, but the α form slowly converts to the β form upon heating to 100&nbsp;°C.<ref name=mor>{{cite book|author1=Gerd Meyer|author2=Lester R. Morss|title=Synthesis of lanthanide and actinide compounds|url=https://books.google.com/books?id=bnS5elHL2w8C&pg=PA44|access-date=11 October 2011|year=1991|publisher=Springer|isbn=978-0-7923-1018-1|pages=44–}}</ref> Both α- and β-UH<sub>3</sub> are [[ferromagnetism|ferromagnetic]] at temperatures below ~180 K. Above 180 K, they are paramagnetic.<ref>{{cite book|author=K. H. J. Buschow|title=Concise encyclopedia of magnetic and superconducting materials|url=https://books.google.com/books?id=N9mvytGEBtwC&pg=PA901|access-date=11 October 2011|year=2005|publisher=Elsevier|isbn=978-0-08-044586-1|pages=901–}}</ref>
 ==Formation in uranium metal==
@@ Line 46: / Line 48: @@
 ===Hydrogen gas reaction===
-Exposition of uranium metal to hydrogen leads to [[hydrogen embrittlement]]. Hydrogen diffuses through metal and forms a network of brittle hydride over the [[grain boundary|grain boundaries]]. Hydrogen can be removed and ductility renewed by [[annealing (metallurgy)|annealing]] in [[vacuum]].<ref>{{cite book|url=https://books.google.com/books?id=eSAkBkAZ-J4C&pg=PA232|title=Plasma and high frequency processes for obtaining and processing materials in the nuclear fuel cycle|publisher=Nova Publishers|year=2003|isbn=1-59033-009-9 |page=232|author=I. N. Toumanov|accessdate=2010-02-07}}</ref>
+Exposure of uranium metal to hydrogen leads to [[hydrogen embrittlement]]. Hydrogen diffuses through metal and forms a network of brittle hydride over the [[grain boundary|grain boundaries]]. Hydrogen can be removed and ductility renewed by [[annealing (metallurgy)|annealing]] in [[vacuum]].<ref>{{cite book|url=https://books.google.com/books?id=eSAkBkAZ-J4C&pg=PA232|title=Plasma and high frequency processes for obtaining and processing materials in the nuclear fuel cycle|publisher=Nova Publishers|year=2003|isbn=1-59033-009-9 |page=232|author=I. N. Toumanov|access-date=2010-02-07}}</ref>
-Uranium metal heated to 250 to 300 [[Celsius|°C]] (482 to 572 [[Fahrenheit|°F]]) reacts with [[hydrogen]] to form '''uranium hydride'''. Further heating to about 500&nbsp;°C will reversibly remove the hydrogen. This property makes uranium hydrides convenient starting materials to create reactive uranium powder along with various uranium [[carbide]], [[nitride]], and [[halide]] compounds.<ref name="EncyChem782">{{Cite book |title=The Encyclopedia of the Chemical Elements |chapter=Uranium |year=1968 |authorlink=Glenn T. Seaborg |first=Glenn T. |last=Seaborg |publisher=Reinhold Book Corporation |location=[[Skokie, Illinois]] |page=782|id=LCCCN 68-29938}}</ref> The reversible reaction proceeds as follows:<ref name=wib>{{cite book|author1=Egon Wiberg|author2=Nils Wiberg|author3=Arnold Frederick Holleman|title=Inorganic chemistry|url=https://books.google.com/books?id=Mtth5g59dEIC&pg=PA239|accessdate=11 October 2011|year=2001|publisher=Academic Press|isbn=978-0-12-352651-9|pages=239–}}</ref>
+Uranium metal heated to 250 to 300 [[Celsius|°C]] (482 to 572 [[Fahrenheit|°F]]) reacts with [[hydrogen]] to form '''uranium hydride'''. Further heating to about 500&nbsp;°C will reversibly remove the hydrogen. This property makes uranium hydrides convenient starting materials to create reactive uranium powder along with various uranium [[carbide]], [[nitride]], and [[halide]] compounds.<ref name="EncyChem782">{{Cite book |title=The Encyclopedia of the Chemical Elements |chapter=Uranium |year=1968 |author-link=Glenn T. Seaborg |first=Glenn T. |last=Seaborg |publisher=Reinhold Book Corporation |location=[[Skokie, Illinois]] |page=782|id=LCCCN 68-29938}}</ref> The reversible reaction proceeds as follows:<ref name=wib>{{cite book|author1=Egon Wiberg|author2=Nils Wiberg|author3=Arnold Frederick Holleman|title=Inorganic chemistry|url=https://books.google.com/books?id=Mtth5g59dEIC&pg=PA239|access-date=11 October 2011|year=2001|publisher=Academic Press|isbn=978-0-12-352651-9|pages=239–}}</ref>
 :2 U + 3 H<sub>2</sub> {{eqm}} 2 UH<sub>3</sub>
-Uranium hydride is not an [[interstitial compound]], causing the metal to expand upon hydride formation. In its [[crystal structure|lattice]], each uranium atom is surrounded by 6 other uranium [[atom]]s and 12 atoms of [[hydrogen]]; each hydrogen atom occupies a large tetrahedral hole in the lattice.<ref name="google1">{{cite book|url=https://books.google.com/books?id=u0ZdEdgLlP0C&pg=PA789|title=Text Book Of Inorganic Chemistry|author=Amit Arora|page=789|publisher=Discovery Publishing House|year=2005 |isbn=81-8356-013-X|accessdate=2010-02-07}}</ref> The density of hydrogen in uranium hydride is approximately the same as in liquid water or in [[liquid hydrogen]].<ref>{{cite book|url=https://books.google.com/books?id=VW7Nl0L0GeoC&pg=PA393|title=Alternative Energy Systems in Building Design (GreenSource Books)|author=Peter Gevorkian|page=393|publisher=McGraw Hill Professional|year=2009|isbn=0-07-162147-4 |accessdate=2010-02-07}}</ref> The U-H-U linkage through a hydrogen atom is present in the structure.<ref>{{cite book|url=https://books.google.com/books?id=0l3bYxwBWMcC&pg=PA218|title=Environmental Pollution |author=G. Singh|publisher=Discovery Publishing House|year=2007|isbn=81-8356-241-8 |accessdate=2010-02-07}}</ref>
+Uranium hydride is not an [[interstitial compound]], causing the metal to expand upon hydride formation. In its [[crystal structure|lattice]], each uranium atom is surrounded by 6 other uranium [[atom]]s and 12 atoms of [[hydrogen]]; each hydrogen atom occupies a large tetrahedral hole in the lattice.<ref name="google1">{{cite book|url=https://books.google.com/books?id=u0ZdEdgLlP0C&pg=PA789|title=Text Book Of Inorganic Chemistry|author=Amit Arora|page=789|publisher=Discovery Publishing House|year=2005 |isbn=81-8356-013-X|access-date=2010-02-07}}</ref> The density of hydrogen in uranium hydride is approximately the same as in liquid water or in [[liquid hydrogen]].<ref>{{cite book|url=https://books.google.com/books?id=VW7Nl0L0GeoC&pg=PA393|title=Alternative Energy Systems in Building Design (GreenSource Books)|author=Peter Gevorkian|page=393|publisher=McGraw Hill Professional|year=2009|isbn=978-0-07-162147-2 |access-date=2010-02-07}}</ref> The U-H-U linkage through a hydrogen atom is present in the structure.<ref>{{cite book|url=https://books.google.com/books?id=0l3bYxwBWMcC&pg=PA218|title=Environmental Pollution |author=G. Singh|publisher=Discovery Publishing House|year=2007|isbn=978-81-8356-241-6 |access-date=2010-02-07}}</ref>
 ===Water reaction===
-Uranium hydride forms when uranium metal in e.g. [[Magnox]] fuel with corroded [[Cladding (nuclear fuel)|cladding]] becomes exposed to water; the reaction proceeds as follows:
+Uranium hydride forms when uranium metal (e.g. in [[Magnox]] fuel with corroded [[Cladding (nuclear fuel)|cladding]]) becomes exposed to water or steam, with [[uranium dioxide]] as byproduct:<ref name="google1"/>
 :7 U + 6 H<sub>2</sub>O → 3 UO<sub>2</sub> + 4 UH<sub>3</sub>
-The resulting uranium hydride is pyrophoric;  if the metal (e.g. a damaged [[fuel rod]]) is exposed to air afterwards, excessive heat may be generated and the bulk uranium metal itself can ignite.<ref>{{cite journal|url=https://books.google.com/books?id=bAwAAAAAMBAJ&pg=PA49|page=49|title=Rust never sleeps|journal=Bulletin of the Atomic Scientists |publisher=Books.google.com |year= 1994|accessdate=2010-02-07|volume=50|issue=5}}</ref> Hydride-contaminated uranium can be [[Passivation (chemistry)|passivated]] by exposition to a gaseous mixture of 98% [[helium]] with 2% [[oxygen]].<ref>{{cite web|url=http://teton.if.uidaho.edu/emsp/overviewflowviz.html |title=EMSP |publisher=Teton.if.uidaho.edu |date= |accessdate=2010-02-07}}</ref> Condensed moisture on uranium metal promotes formation of hydrogen and uranium hydride; a pyrophoric surface may be formed in absence of oxygen.<ref>{{cite book|url=https://books.google.com/books?id=hcPYAAANpGYC&pg=PT16|title=Advanced nuclear fuel cycles and radioactive waste management|page=176|author=OECD Nuclear Energy Agency|publisher=OECD Publishing|year= 2006|isbn=92-64-02485-9|accessdate=2010-02-07}}</ref> This poses a problem with underwater storage of [[spent nuclear fuel]] in [[spent fuel pond]]s. Depending on the size and distribution on the hydride particles, self-ignition can occur after an indeterminate length of exposure to air.<ref>{{cite book|url=https://books.google.com/books?id=CrIz5k3ALv8C&pg=PA197|title=Stabilisation/Solidification Treatment and Remediation: Proceedings of the International Conference on Stabilisation/Solidification Treatment and Remediation, 12–13 April 2005, Cambridge, UK|author1=Abir Al-Tabbaa |author2=J. A. Stegemann |page=197| publisher=Taylor & Francis|year=2005|isbn=0-415-37460-X|accessdate=2010-02-07}}</ref> Such exposure poses risk of self-ignition of fuel debris in radioactive waste storage vaults.<ref>{{cite book|url=https://books.google.com/books?id=UWURYnLlQzQC&pg=PA278|page=278|title=International Conference on Nuclear Decom 2001: ensuring safe, secure and successful decommissioning : 16–18 October 2001 Commonwealth Conference and Events Centre, London UK, Issue 8|publisher=John Wiley and Sons|year=2001|accessdate=2010-02-07|isbn=1-86058-329-6}}</ref>
+The resulting uranium hydride is pyrophoric;  if the metal (e.g. a damaged [[fuel rod]]) is exposed to air afterwards, excessive heat may be generated and the bulk uranium metal itself can ignite.<ref>{{cite journal|url=https://books.google.com/books?id=bAwAAAAAMBAJ&pg=PA49|page=49|title=Rust never sleeps|journal=Bulletin of the Atomic Scientists |year= 1994|access-date=2010-02-07|volume=50|issue=5}}</ref> Hydride-contaminated uranium can be [[Passivation (chemistry)|passivated]] by exposure to a gaseous mixture of 98% [[helium]] with 2% [[oxygen]].<ref>{{cite web |url=http://teton.if.uidaho.edu/emsp/overviewflowviz.html |title=EMSP |publisher=Teton.if.uidaho.edu |access-date=2010-02-07 |archive-url=https://web.archive.org/web/20090930205434/http://teton.if.uidaho.edu/emsp/overviewflowviz.html |archive-date=2009-09-30  }}</ref> Condensed moisture on uranium '''metal''' promotes formation of hydrogen and uranium hydride; a pyrophoric surface may be formed in absence of oxygen.<ref>{{cite book|url=https://books.google.com/books?id=hcPYAAANpGYC&pg=PT16|title=Advanced nuclear fuel cycles and radioactive waste management|page=176|author=OECD Nuclear Energy Agency|publisher=OECD Publishing|year= 2006|isbn=92-64-02485-9|access-date=2010-02-07}}</ref> This poses a problem with underwater storage of very special [[spent nuclear fuel]] in [[spent fuel pond]]s (nuclear fuel from commercial nuclear plants does NOT contain any uranium metal). Depending on the size and distribution on the hydride particles, self-ignition can occur after an indeterminate length of exposure to air.<ref>{{cite book|url=https://books.google.com/books?id=CrIz5k3ALv8C&pg=PA197|title=Stabilisation/Solidification Treatment and Remediation: Proceedings of the International Conference on Stabilisation/Solidification Treatment and Remediation, 12–13 April 2005, Cambridge, UK|author1=[[Abir Al-Tabbaa]] |author2=J. A. Stegemann |page=197| publisher=Taylor & Francis|year=2005|isbn=0-415-37460-X|access-date=2010-02-07}}</ref> Such exposure poses risk of self-ignition of fuel debris in radioactive waste storage vaults.<ref>{{cite book|url=https://books.google.com/books?id=UWURYnLlQzQC&pg=PA278|page=278|title=International Conference on Nuclear Decom 2001: ensuring safe, secure and successful decommissioning: 16–18 October 2001 Commonwealth Conference and Events Centre, London UK, Issue 8|publisher=John Wiley and Sons|year=2001|access-date=2010-02-07|isbn=1-86058-329-6}}</ref>
+Uranium hydride exposed to water evolves hydrogen. In contact with strong oxidizers this may cause fire and explosions. Contact with [[halocarbon]]s may cause a violent reaction.<ref>{{cite web |url=http://www.osha.gov/SLTC/healthguidelines/uraniuminsolublecompounds/recognition.html |title=Uranium & Insoluble Compounds |publisher=Osha.gov |access-date=2010-02-07 |archive-url=https://web.archive.org/web/20100322215227/http://www.osha.gov/SLTC/healthguidelines/uraniuminsolublecompounds/recognition.html |archive-date=2010-03-22  }}</ref>
-Uranium metal exposed to steam produces a mixture of uranium hydride and [[uranium dioxide]].<ref name="google1"/>
-Uranium hydride exposed to water evolves hydrogen. In contact with strong oxidizers this may cause fire and explosions. Contact with [[halocarbon]]s may cause a violent reaction.<ref>{{cite web|url=http://www.osha.gov/SLTC/healthguidelines/uraniuminsolublecompounds/recognition.html |title=Uranium & Insoluble Compounds |publisher=Osha.gov |date= |accessdate=2010-02-07}}</ref>
 ==Other chemical reactions==
-[[Polystyrene]]-impregnated uranium hydride powder is non-pyrophoric and can be pressed, however its hydrogen-carbon ratio is unfavorable. Hydrogenated polystyrene was introduced in 1944 instead.<ref name="critas">{{cite book|url=https://books.google.com/books?id=KoTve97yYB8C&pg=PA211|title=Critical Assembly: A Technical History of Los Alamos During the Oppenheimer Years, 1943–1945|isbn=0-521-54117-4|publisher=Cambridge University Press|year=2004|author=Lillian Hoddeson|page=211 |accessdate=2010-02-07|display-authors=etal}}</ref>
+[[Polystyrene]]-impregnated uranium hydride powder is non-pyrophoric and can be pressed, however its hydrogen-carbon ratio is unfavorable. Hydrogenated polystyrene was introduced in 1944 instead.<ref name="critas">{{cite book|url=https://books.google.com/books?id=KoTve97yYB8C&pg=PA211|title=Critical Assembly: A Technical History of Los Alamos During the Oppenheimer Years, 1943–1945|isbn=0-521-54117-4|publisher=Cambridge University Press|year=2004|author=Lillian Hoddeson|page=211 |access-date=2010-02-07|display-authors=etal}}</ref>
 Uranium deuteride is said to be usable for design of some types of [[neutron initiator]]s.
-Uranium hydride [[Nuclear enrichment|enriched]] to about 5% [[uranium-235]] is proposed as a combined [[nuclear fuel]]/[[neutron moderator]] for the [[Hydrogen Moderated Self-regulating Nuclear Power Module]]. According to the aforementioned patent application, the reactor design in question begins producing power when [[hydrogen]] gas at a sufficient temperature and pressure is admitted to the core (made up of granulated uranium metal) and reacts with the uranium metal to form uranium hydride.<ref name="USPatApp11804450">{{cite web |url=http://www.google.com/patents?id=_WGoAAAAEBAJ&zoom=4&pg=PA1|title=Patent Application 11/804450: Self-regulating nuclear power module |last=Peterson|first=Otis G. |date=2008-03-20 |work=United States Patent Application Publication |publisher=United States Patent and Trademark Office, Federal Government of the United States, Washington, DC, USA |accessdate=2009-09-05}}</ref> Uranium hydride is both a [[nuclear fuel]] and a [[neutron moderator]]; apparently it, like other neutron moderators, will slow neutrons sufficiently to allow for fission reactions to take place; the uranium-235 atoms within the hydride also serve as the nuclear fuel. Once the nuclear reaction has started, it will continue until it reaches a certain temperature, approximately {{convert|800|°C|-2}}, where, due to the chemical properties of uranium hydride, it chemically decomposes and turns into hydrogen gas and uranium metal. The loss of neutron moderation due to the chemical [[decomposition reaction|decomposition]] of the uranium hydride will consequently slow — and eventually halt — the reaction. When temperature returns to an acceptable level, the hydrogen will again combine with the uranium metal, forming uranium hydride, restoring moderation and the nuclear reaction will start again.<ref name="USPatApp11804450" />
+Uranium hydride [[Nuclear enrichment|enriched]] to about 5% [[uranium-235]] is proposed as a combined [[nuclear fuel]]/[[neutron moderator]] for the [[Hydrogen Moderated Self-regulating Nuclear Power Module]]. According to the aforementioned patent application, the reactor design in question begins producing power when [[hydrogen]] gas at a sufficient temperature and pressure is admitted to the core (made up of granulated uranium metal) and reacts with the uranium metal to form uranium hydride.<ref name="USPatApp11804450">{{cite web |url=https://patents.google.com/patent/US20080069289|title=Patent Application 11/804450: Self-regulating nuclear power module |last=Peterson|first=Otis G. |date=2008-03-20 |work=United States Patent Application Publication |publisher=United States Patent and Trademark Office, Federal Government of the United States, Washington, DC, USA |access-date=2009-09-05}}</ref> Uranium hydride is both a [[nuclear fuel]] and a [[neutron moderator]]; apparently it, like other neutron moderators, will slow neutrons sufficiently to allow for fission reactions to take place; the uranium-235 atoms within the hydride also serve as the nuclear fuel. Once the nuclear reaction has started, it will continue until it reaches a certain temperature, approximately {{convert|800|°C|-2}}, where, due to the chemical properties of uranium hydride, it chemically decomposes and turns into hydrogen gas and uranium metal. The loss of neutron moderation due to the chemical [[decomposition reaction|decomposition]] of the uranium hydride will consequently slow — and eventually halt — the reaction. When temperature returns to an acceptable level, the hydrogen will again combine with the uranium metal, forming uranium hydride, restoring moderation and the nuclear reaction will start again.<ref name="USPatApp11804450" />
+On heating with [[diborane]], uranium hydride produces [[uranium boride]].<ref>{{cite book|url=https://books.google.com/books?id=qi0vujzNSz4C&pg=PA235|title=Advances in inorganic chemistry and radiochemistry|volume=16|author= Harry Julius Emeléus|page=235|publisher=Academic Press|year=1974|isbn=0-12-023616-8 |access-date=2010-02-07|author-link=Harry Julius Emeléus}}</ref> With [[bromine]] at 300&nbsp;°C, [[uranium(IV) bromide]] is produced. With [[chlorine]] at 250&nbsp;°C, [[uranium(IV) chloride]] is produced. [[Hydrogen fluoride]] at 20&nbsp;°C produces [[uranium(IV) fluoride]]. [[Hydrogen chloride]] at 300&nbsp;°C produces [[uranium(III) chloride]]. [[Hydrogen bromide]] at 300&nbsp;°C produces [[uranium(III) bromide]]. [[Hydrogen iodide]] at 300&nbsp;°C produces [[uranium(III) iodide]]. [[Ammonia]] at 250&nbsp;°C produces [[uranium(III) nitride]]. [[Hydrogen sulfide]] at 400&nbsp;°C produces [[uranium(IV) sulfide]]. [[Oxygen]] at 20&nbsp;°C produces [[triuranium octoxide]]. Water at 350&nbsp;°C produces [[uranium dioxide]].<ref>{{cite book|url=https://books.google.com/books?id=SvAbtU6XvzgC&pg=PT12|title=Lanthanide and actinide chemistry|author=Simon Cotton|page=170|publisher=John Wiley and Sons|year=2006|isbn=0-470-01006-1 |access-date=2010-02-07}}</ref>
-'''Uranium zirconium hydride''' (UZrH), a combination of uranium hydride and [[zirconium(II) hydride]], is used as a fuel/moderator in the [[TRIGA]]-class reactors.
+Uranium hydride ion may interfere with some [[mass spectrometry]] measurements, appearing as a peak at mass 239, creating false increase of signal for plutonium-239.<ref>{{cite book|url=https://books.google.com/books?id=W3FnEOg8tS4C&pg=PA243|title=Nuclear forensic analysis|author1=Kenton James Moody |author2=Ian D. Hutcheon |author3=Patrick M. Grant |page=243|publisher=CRC Press|year=2005|isbn=0-8493-1513-1 |access-date=2010-02-07}}</ref>
-On heating with [[diborane]], uranium hydride produces [[uranium boride]].<ref>{{cite book|url=https://books.google.com/books?id=qi0vujzNSz4C&pg=PA235|title=Advances in inorganic chemistry and radiochemistry|volume=16|author= [[Harry Julius Emeléus]]|page=235|publisher=Academic Press|year=1974|isbn=0-12-023616-8 |accessdate=2010-02-07}}</ref> With [[bromine]] at 300&nbsp;°C, [[uranium(IV) bromide]] is produced. With [[chlorine]] at 250&nbsp;°C, [[uranium(IV) chloride]] is produced. [[Hydrogen fluoride]] at 20&nbsp;°C produces [[uranium(IV) fluoride]]. [[Hydrogen chloride]] at 300&nbsp;°C produces [[uranium(III) chloride]]. [[Hydrogen bromide]] at 300&nbsp;°C produces [[uranium(III) bromide]]. [[Hydrogen iodide]] at 300&nbsp;°C produces [[uranium(III) iodide]]. [[Ammonia]] at 250&nbsp;°C produces [[uranium(III) nitride]]. [[Hydrogen sulfide]] at 400&nbsp;°C produces [[uranium(IV) sulfide]]. [[Oxygen]] at 20&nbsp;°C produces [[triuranium octoxide]]. Water at 350&nbsp;°C produces [[uranium dioxide]].<ref>{{cite book|url=https://books.google.com/books?id=SvAbtU6XvzgC&pg=PT12|title=Lanthanide and actinide chemistry|author=Simon Cotton|page=170|publisher=John Wiley and Sons|year=2006|isbn=0-470-01006-1 |accessdate=2010-02-07}}</ref>
-Uranium hydride ion may interfere with some [[mass spectrometry]] measurements, appearing as a peak at mass 239, creating false increase of signal for plutonium-239.<ref>{{cite book|url=https://books.google.com/books?id=W3FnEOg8tS4C&pg=PA243|title=Nuclear forensic analysis|author1=Kenton James Moody |author2=Ian D. Hutcheon |author3=Patrick M. Grant |page=243|publisher=CRC Press|year=2005|isbn=0-8493-1513-1 |accessdate=2010-02-07}}</ref>
 ==History==
-Uranium hydride slugs were used in the "[[Demon core|tickling the dragon's tail]]" series of experiments to determine the [[critical mass]] of uranium.<ref>{{cite web|url=http://www.mphpa.org/classic/LA/Photo-Pages-2/LAP-217.htm |title=Photo – Tickling the Dragon's Tail |publisher=Mphpa.org |date=2005-08-03 |accessdate=2010-02-07}}</ref>
+Uranium hydride slugs were used in the "[[Demon core|tickling the dragon's tail]]" series of experiments to determine the [[critical mass]] of uranium.<ref>{{cite web |url=http://www.mphpa.org/classic/LA/Photo-Pages-2/LAP-217.htm |title=Photo – Tickling the Dragon's Tail |publisher=Mphpa.org |date=2005-08-03 |access-date=2010-02-07 |archive-date=2010-02-18 |archive-url=https://web.archive.org/web/20100218112800/http://www.mphpa.org/classic/LA/Photo-Pages-2/LAP-217.htm  }}</ref>
-Uranium hydride and uranium [[deuterium|deuteride]] were suggested as a [[fissile material]] for a [[uranium hydride bomb]]. The tests with uranium hydride and uranium deuteride during [[Operation Upshot–Knothole]] were disappointing, however. During the early phases of the [[Manhattan Project]], in 1943, uranium hydride was investigated as a promising bomb material; however, it was abandoned by the spring of 1944 as it turned out that such a design would be inefficient.<ref>{{cite journal|url=https://books.google.com/books?id=VAwAAAAAMBAJ&pg=PA2|page=2|title=Lying well|journal=Bulletin of the Atomic Scientists |publisher=Books.google.com |date= July 1994|accessdate=2010-02-07|volume=50|issue=4}}
+Uranium hydride and uranium [[deuterium|deuteride]] were suggested as a [[fissile material]] for a [[uranium hydride bomb]]. The tests with uranium hydride and uranium deuteride during [[Operation Upshot–Knothole]] were disappointing, however. During the early phases of the [[Manhattan Project]], in 1943, uranium hydride was investigated as a promising bomb material; it was abandoned by early 1944 as it turned out that such a design would be inefficient.<ref>{{cite journal|url=https://books.google.com/books?id=VAwAAAAAMBAJ&pg=PA2|page=2|title=Lying well|journal=Bulletin of the Atomic Scientists |date= July 1994|access-date=2010-02-07|volume=50|issue=4|doi=10.1080/00963402.1994.11456528|bibcode=1994BuAtS..50d...2M|last1=Moore|first1=Mike}}
 </ref>
 ==Applications==
-Hydrogen, [[deuterium]], and [[tritium]] can be purified by reacting with uranium, then thermally decomposing the resulting hydride/deuteride/tritide.<ref>{{cite book|url=https://books.google.com/books?id=MYCBJIKpC2gC&pg=PA104|title=Thermophysical properties of lithium hydride, deuteride, and tritide and of their solutions with lithium|page=104 |publisher=Springer|year=1987|isbn=0-88318-532-6|author=E. E. Shpil'rain |accessdate=2010-02-07}}</ref> Extremely pure hydrogen has been prepared from beds of uranium hydride for decades.<ref>{{cite book|url=https://books.google.com/books?id=Na8jRpkPffkC&pg=PA263|page=264 |title=Hydrogen energy system: production and utilization of hydrogen and future aspects|publisher=Springer|year= 1995|accessdate=2010-02-07|isbn=0-7923-3601-1|author=Yuda Yürüm}}</ref> Heating uranium hydride is a convenient way to introduce hydrogen into a vacuum system.<ref>{{cite book|url=https://books.google.com/books?id=yBmnnaODnHgC&pg=PA121|title=Handbook of electron tube and vacuum techniques|author=Fred Rosebury|page=121|publisher=Springer|year=1992|isbn=1-56396-121-0 |accessdate=2010-02-07}}</ref>
+Hydrogen, [[deuterium]], and [[tritium]] can be purified by reacting with uranium, then thermally decomposing the resulting hydride/deuteride/tritide.<ref>{{cite book|url=https://books.google.com/books?id=MYCBJIKpC2gC&pg=PA104|title=Thermophysical properties of lithium hydride, deuteride, and tritide and of their solutions with lithium|page=104 |publisher=Springer|year=1987|isbn=0-88318-532-6|author=E. E. Shpil'rain |access-date=2010-02-07}}</ref> Extremely pure hydrogen has been prepared from beds of uranium hydride for decades.<ref>{{cite book|url=https://books.google.com/books?id=Na8jRpkPffkC&pg=PA263|page=264 |title=Hydrogen energy system: production and utilization of hydrogen and future aspects|publisher=Springer|year= 1995|access-date=2010-02-07|isbn=0-7923-3601-1|author=Yuda Yürüm}}</ref> Heating uranium hydride is a convenient way to introduce hydrogen into a vacuum system.<ref>{{cite book|url=https://books.google.com/books?id=yBmnnaODnHgC&pg=PA121|title=Handbook of electron tube and vacuum techniques|author=Fred Rosebury|page=121|publisher=Springer|year=1992|isbn=1-56396-121-0 |access-date=2010-02-07}}</ref>
 The swelling and pulverization at uranium hydride synthesis can be used for preparation of very fine uranium metal, if the powdered hydride is thermally decomposed.
 Uranium hydride can be used for [[isotope separation]] of [[hydrogen]], preparing uranium metal powder, and as a [[reducing agent]].
+Uranium tritide (UT) is used for the safe and efficient storage of tritium, since gaseous tritium is harder to contain and work with. UT is formed by combining tritium and uranium at room temperature. The tritium can be later extracted by heating the UT. Tritium and its decay product <sup>3</sup>He are extracted at different temperatures.<ref>{{Cite web |date=2022 |title=NIS - Tritium Uses |url=https://www.nuclearinfo.org/wp-content/uploads/2022/05/Tritium_uses_nd..pdf |access-date=2024-12-12 |website=NIS Nuclear Info}}</ref>
 ==References==
-{{reflist|2}}
+{{reflist|30em}}
 {{uranium compounds}}
+{{hydrides by group}}
 [[Category:Metal hydrides]]
@@ Line 99: / Line 100: @@
 [[Category:Neutron moderators]]
 [[Category:Reducing agents]]
-[[Category:Uranium]]
+[[Category:Uranium(III) compounds]]
+[[Category:Ferromagnetic materials]]
+[[Category:Pyrophoric materials]]