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For tools
| Atomic Number: |
23 |
| Atomic Symbol: |
V |
| Atomic Weight: |
50.9414 |
| Electron Configuration: |
[Ar]4s23d3 |
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.
Sources
Vanadium 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 magnesium or 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.
Properties
Pure 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 660oC.
The metal has good structural strength and a low fission neutron cross section, making
it useful in nuclear applications.
Uses
Vanadium is used in producing rust resistant and high speed 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.
Handling
Vanadium 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).
Costs
Ductile 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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