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| Atomic Number: | 23 | Atomic Symbol: | V | | Atomic Weight: | 50.9414 | Electron Configuration: | 2-8-11-2 | | Shells: | 2,8,11,2 | Filling Orbital: | 3d3 | | Melting Point: | 1890oC ?? 10oC | Boiling Point: | 3380oC | | Uses: | tools, V2O5 as catalyst, dye, color-fixer
etc. |
History(Scandinavian goddess, Vanadis) Vanadium was first discovered by
del Rio in 1801. Unfortunately, a French chemist incorrectly declared that del
Rio's new element was only impure chromium. Del Rio thought
himself to be mistaken and accepted the French chemists's statement.
The element was rediscovered in 1830 by Sefstrom, who named the element in
honor of the Scandinavian goddess, Vanadis, because of its beautiful
multicolored compounds. It was isolated in nearly pure form by Roscoe, in 1867,
who reduced the chloride with hydrogen.
Vanadium of 99.3 to 99.8% purity was not produced until 1922.
SourcesVanadium is found in about 65 different minerals among which are
carnotite, roscoelite, vanadinite, and patronite, important sources of the
metal. Vanadium is also found in phosphate rock and certain iron ores, and is
present in some crude oils in the form of organic complexes. It is also found in
small percentages in meteorites.
Commercial production from petroleum ash holds promise as an important source
of the element. High-purity ductile vanadium can be obtained by reduction of
vanadium trichloride with magnesiumor with
magnesium-sodium mixtures.
Much of the vanadium metal being produced is now made by calcium reduction of V2O5 in a pressure vessel, an adaption of
a process developed by McKechnie and Seybair. Natural vanadium is a mixture of
two isotopes, 50V (0.24%) and 51V (99.76%). 50V is slightly radioactive, having
a half-life of > 3.9 x 1017 years. Nine other unstable isotopes
are recognized.
PropertiesPure vanadium is a bright white metal, and is soft and
ductile. It has good corrosion resistance to alkalis, sulfuric and hydrochloric
acid, and salt water, but the metal oxidizes readily above 660C.
The metal has good structural strength and a low fission neutron cross
section, making it useful in nuclear applications.
UsesVanadium is used in producing rust resistant and highspeed tools
steels. It is an important carbide stabilizer in making steels.
About 80% of the vanadium now produced is used as ferrovanadium or as a steel
additive. Vanadium foil is used as a bonding agent in cladding titanium to
steel. Vanadium pentoxide is used in ceramics and as a catalyst.
It is also used to produce a superconductive magnet with a field of 175,000
gauss.
HandlingVanadium and its compounds are toxic and should be handled with
care. The maximum allowable concentration of V2O5 dust in
air is about 0.05 (8-hour time-weighted average - 40-hour week).
CostsDuctile vanadium is commercially available. Commercial vanadium
metal, of about 95% purity, costs about $20/lb. Vanadium (99.9%) costs about
$100/oz.
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