Editing Vanadium (section)

== Production ==
[[File:Vanadium-production(en).svg|thumb|Vanadium production trend]]
[[File:Vanadium crystal vakuum sublimed.jpg|thumb|left|Vacuum sublimed vanadium [[dendrite (crystal)|dendritic]] crystals (99.9%)]]

Vanadium metal is obtained by a multistep process that begins with roasting crushed ore with [[sodium chloride|NaCl]] or [[sodium carbonate|Na<sub>2</sub>CO<sub>3</sub>]] at about 850&nbsp;°C to give [[sodium metavanadate]] (NaVO<sub>3</sub>). An aqueous extract of this solid is acidified to produce "red cake", a polyvanadate salt, which is reduced with [[calcium]] metal. As an alternative for small-scale production, vanadium pentoxide is reduced with [[hydrogen]] or [[magnesium]]. Many other methods are also used, in all of which vanadium is produced as a [[byproduct]] of other processes.<ref name="Moskalyk">{{cite journal |last1=Moskalyk |first1=R.R |last2=Alfantazi |first2=A.M |date=September 2003 |title=Processing of vanadium: a review |journal=Minerals Engineering |volume=16 |issue=9 |pages=793–805 |bibcode=2003MiEng..16..793M |doi=10.1016/S0892-6875(03)00213-9}}</ref> Purification of vanadium is possible by the [[crystal bar process]] developed by [[Anton Eduard van Arkel]] and [[Jan Hendrik de Boer]] in 1925. It involves the formation of the metal iodide, in this example [[vanadium(III) iodide]], and the subsequent decomposition to yield pure metal:<ref>{{cite journal |last1=Carlson |first1=O. N. |last2=Owen |first2=C. V. |date=1961 |title=Preparation of High-Purity Vanadium Metalb by the Iodide Refining Process |journal=Journal of the Electrochemical Society |volume=108 |issue=1 |pages=88 |doi=10.1149/1.2428019}}</ref>
:2 V + 3 I<sub>2</sub> {{eqm}} 2 VI<sub>3</sub>

[[File:FerroVanadium.jpg|thumb|Ferrovanadium chunks]]

Most vanadium is used as a [[steel]] alloy called [[ferrovanadium]]. Ferrovanadium is produced directly by reducing a mixture of vanadium oxide, iron oxides and iron in an electric furnace. The vanadium ends up in [[pig iron]] produced from vanadium-bearing magnetite. Depending on the ore used, the slag contains up to 25% of vanadium.<ref name="Moskalyk" />