Chemical elements
  Niobium
      Occurrence
      History
    Isotopes
    Energy
    Production
    Application
    Physical Properties
    Chemical Properties

Element Niobium, Nb, Transition Metal





History

Main article History of Niobium

Niobium was discovered by Charles Hatchett in 1801, who found it in columbite ore. Hatchett first mistakenly considered columbite as Siberian chromium ore. However, later he found out that the properties of the "new earth" were completely different and implied the existence of a new element. Despite the failure of attempts to extract this new metal, Hatchett called the element columbium after Christopher Columbus and the first name of America.

In 1802 tantalum was discovered by the Swedish chemist Anders Gustaf Ekeberg and named after the mythological character Tantalus because of the tantalizing problem of dissolving the oxide in acids. The mineral was called tantalite. In 1809 William Hyde Wollaston identified Hatchet's columbium Ekeberg's tantalum by the similar density. The problem was resolved in 1846 by Heinrich Rose and who, after thorough analysis of columbites and tantalites discovered the element. Since Rose was unaware of Hatchett's work, he gave the element a different name, niobium after Niobe, daughter of Tantalus in Greek mythology.


Occurrence

Main article Occurrence of Niobium

The crustal abundance of Niobium is 2x10-3 % by mass. In nature Niobium is associated by Tantalum. It occurs in the minerals columbite columbite-tantalite or coltan, pyrochlore and loparite. Columbite-tantalite (Fe,Mn)(Nb,Ta)2O6 contains 82-86% of Niobium and Tantalum oxides. If Niobium percentage exceeds that of Tantalum the mineral is called columbite, otherwise it is tantalite. Pyrochlore (Na,Ca,Ce)2(Nb,Ti)2(OH,F)O6 contains 37.5-65.6% of Nb2O5, and loparite (Na,Ca,Ce,Sr,Nb,Ti)O3 has 8-10% of the same oxide. Niobium minerals are slightly paramagnetic and radioactive because of Uranium-Thorium impurities. Columbite together with tantalite can be found in igneous pegmatites; columbite is an accessory constituent of various biotite granites as well as alkaline granites and, sometimes, in placer deposits in Nigeria. Columbite may be recovered from a tin smelting slag waste dump.

Pyrochlore occurs in carbonatites, in pegmatites associated with nepheline syenites and other alkalic rocks (Canada) as well as in sedentary products of syenites-carbonatites weathering (Brazil).

The world supply of niobium was 18 million tons in 1980. Nearly ninety percent of the United States' niobium supply comes from Brazil and Canada, which collectively mine some 32,000 tons of material annually.

Neighbours



Chemical Elements

22Ti
47.9
Titanium
23V
50.9
Vanadium
24Cr
52.0
Chromium
40Zr
91.2
Zirconium
41Nb
92.9
Niobium
42Mo
95.9
Molybdenum
72Hf
178.5
Hafnium
73Ta
180.9
Tantalum
74W
183.8
Tungsten

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