Editing Niobium (section)

==Production==
[[File:World Niobium Production 2006.svg|upright=1.4|thumb|Niobium producers in 2006 to 2015 |alt=Grey and white world map with Brazil colored red representing 90% of niobium world production and Canada colored in dark blue representing 5% of niobium world production]]

After the separation from the other minerals, the [[mixed oxide]]s of tantalum [[tantalum pentoxide|{{chem2|Ta2O5}}]] and niobium [[Niobium pentoxide|{{chem2|Nb2O5}}]] are obtained. The first step in the processing is the reaction of the oxides with [[hydrofluoric acid]]:<ref name="ICE" />

:{{chem2|Ta2O5 + 14 HF → 2 H2[TaF7] + 5 H2O}}
:{{chem2|Nb2O5 + 10 HF → 2 H2[NbOF5] + 3 H2O}}

The first industrial scale separation, developed by [[Switzerland|Swiss]] [[chemist]] [[Jean Charles Galissard de Marignac|de Marignac]], exploits the differing [[Solubility|solubilities]] of the complex niobium and tantalum [[fluoride]]s, dipotassium oxypentafluoroniobate monohydrate ({{chem2|K2[NbOF5]*H2O}}) and dipotassium heptafluorotantalate ({{chem2|K2[TaF7]}}) in water. Newer processes use the liquid extraction of the fluorides from [[aqueous]] solution by [[organic solvents]] like [[cyclohexanone]].<ref name="ICE" /> The complex niobium and tantalum fluorides are extracted separately from the [[organic solvent]] with water and either precipitated by the addition of [[potassium fluoride]] to produce a potassium fluoride complex, or precipitated with [[ammonia]] as the pentoxide:<ref name="HollemanAF" />

:{{chem2|H2[NbOF5] + 2 KF → K2[NbOF5]↓ + 2 HF}}

Followed by:
:{{chem2|2 H2[NbOF5] + 10 NH4OH → Nb2O5↓ + 10 NH4F + 7 H2O}}

Several methods are used for the [[Reduction (chemistry)|reduction]] to metallic niobium. The [[electrolysis]] of a [[Molten salt|molten mixture]] of {{chem2|K2}}[{{chem2|NbOF5}}] and [[sodium chloride]] is one; the other is the reduction of the fluoride with [[sodium]]. With this method, a relatively high purity niobium can be obtained. In large scale production, {{chem2|Nb2O5}} is reduced with hydrogen or carbon.<ref name="HollemanAF" /> In the [[aluminothermic reaction]], a mixture of [[iron oxide]] and niobium oxide is reacted with [[aluminium]]:
:{{chem2|3 Nb2O5 + Fe2O3 + 12 Al → 6 Nb + 2 Fe + 6 Al2O3}}

Small amounts of oxidizers like [[sodium nitrate]] are added to enhance the reaction. The result is [[aluminium oxide]] and [[ferroniobium]], an alloy of iron and niobium used in steel production.<ref>{{cite book|title = Progress in Niobium Markets and Technology 1981–2001|author = Tither, Geoffrey|url = https://www.cbmm.com/portug/sources/techlib/science_techno/table_content/images/pdfs/oppening.pdf |date = 2001| publisher=Niobium 2001 Limited |isbn = 978-0-9712068-0-9|editor = Minerals, Metals and Materials Society|url-status = dead|archive-url = https://web.archive.org/web/20081217100553/http://www.cbmm.com.br/portug/sources/techlib/science_techno/table_content/images/pdfs/oppening.pdf|archive-date = 17 December 2008|df = dmy-all}}</ref><ref>{{cite book|title=The Production of Ferroniobium at the Niobec mine 1981–2001 |first=Claude |last=Dufresne |author2=Goyette, Ghislain |url=https://www.cbmm.com/portug/sources/techlib/science_techno/table_content/sub_1/images/pdfs/start.pdf |date=2001 |publisher=Niobium 2001 Limited |isbn=978-0-9712068-0-9 |editor = Minerals, Metals and Materials Society |url-status=dead |archive-url=https://web.archive.org/web/20081217100559/http://www.cbmm.com.br/portug/sources/techlib/science_techno/table_content/sub_1/images/pdfs/start.pdf |archive-date=17 December 2008 }}</ref> Ferroniobium contains between 60 and 70% niobium.<ref name="tesla" /> Without iron oxide, the aluminothermic process is used to produce niobium. Further purification is necessary to reach the grade for [[superconductive]] alloys. [[Electron beam melting]] under vacuum is the method used by the two major distributors of niobium.<ref name="Aguly" /><ref name="Chou">{{cite journal|journal = The Iron and Steel Institute of Japan International|volume = 32|date = 1992|issue = 5|doi = 10.2355/isijinternational.32.673|title = Electron Beam Melting and Refining of Metals and Alloys|first = Alok|last = Choudhury|author2=Hengsberger, Eckart |pages = 673–681|doi-access = free}}</ref>

{{as of|2013}}, [[Companhia Brasileira de Metalurgia e Mineração|CBMM]] from Brazil controlled 85 percent of the world's niobium production.<ref name="lucchesi2013">{{Citation
 |last1=Lucchesi |first1=Cristane |last2=Cuadros|first2=Alex |date=April 2013 |title=Mineral Wealth |type=paper |magazine=[[Bloomberg Markets]] |page=14}}</ref> The [[United States Geological Survey]] estimates that the production increased from 38,700 tonnes in 2005 to 44,500 tonnes in 2006.<ref name="USGSCS2006">{{cite web |url=http://minerals.usgs.gov/minerals/pubs/commodity/niobium/colummcs06.pdf |title=Niobium (Columbium) |first=John F. |last=Papp |publisher=USGS 2006 Commodity Summary |access-date=20 November 2008 |archive-date=17 December 2008 |archive-url=https://web.archive.org/web/20081217100548/http://minerals.usgs.gov/minerals/pubs/commodity/niobium/colummcs06.pdf |url-status=live }}</ref><ref name="USGSCS2007">{{cite web |url=http://minerals.usgs.gov/minerals/pubs/commodity/niobium/colummcs07.pdf |title=Niobium (Columbium) |first=John F. |last=Papp |publisher=USGS 2007 Commodity Summary |access-date=20 November 2008 |archive-date=5 August 2017 |archive-url=https://web.archive.org/web/20170805170910/https://minerals.usgs.gov/minerals/pubs/commodity/niobium/colummcs07.pdf |url-status=live }}</ref> Worldwide resources are estimated to be 4.4 million tonnes.<ref name="USGSCS2007" /> During the ten-year period between 1995 and 2005, the production more than doubled, starting from 17,800 tonnes in 1995.<ref name="USGSCS1997">{{cite web|url = http://minerals.usgs.gov/minerals/pubs/commodity/niobium/230397.pdf|title = Niobium (Columbium)|first = John F.|last = Papp|publisher = USGS 1997 Commodity Summary|access-date = 20 November 2008|archive-date = 11 January 2019|archive-url = https://web.archive.org/web/20190111003407/https://minerals.usgs.gov/minerals/pubs/commodity/niobium/230397.pdf|url-status = live}}</ref> Between 2009 and 2011, production was stable at 63,000 tonnes per year,<ref>[http://minerals.usgs.gov/minerals/pubs/commodity/niobium/mcs-2011-niobi.pdf Niobium (Colombium)] {{Webarchive|url=https://web.archive.org/web/20120708152542/http://minerals.usgs.gov/minerals/pubs/commodity/niobium/mcs-2011-niobi.pdf |date=8 July 2012 }} U.S. Geological Survey, Mineral Commodity Summaries, January 2011</ref> with a slight decrease in 2012 to only 50,000 tonnes per year.<ref>[http://minerals.usgs.gov/minerals/pubs/commodity/niobium/mcs-2016-niobi.pdf Niobium (Colombium)] {{Webarchive|url=https://web.archive.org/web/20160306095041/http://minerals.usgs.gov/minerals/pubs/commodity/niobium/mcs-2016-niobi.pdf |date=6 March 2016 }} U.S. Geological Survey, Mineral Commodity Summaries, January 2016</ref>

{| class="wikitable" style="text-align:right;"
|+ Mine production (t)<ref name="USGSNiobi">{{cite web |author=Cunningham, Larry D. |url=http://minerals.usgs.gov/minerals/pubs/commodity/niobium/ |title=USGS Minerals Information: Niobium (Columbium) and Tantalum |publisher=Minerals.usgs.gov |date=5 April 2012 |access-date=17 August 2012 |archive-date=28 January 2013 |archive-url=https://web.archive.org/web/20130128101220/http://minerals.usgs.gov/minerals/pubs/commodity/niobium/ |url-status=live }}</ref> (USGS estimate)<ref>{{Cite web|url=https://www.usgs.gov/centers/nmic/niobium-columbium-and-tantalum-statistics-and-information|title=Niobium (Columbium) and Tantalum Statistics and Information &#124; U.S. Geological Survey|access-date=2 December 2021|archive-date=6 March 2019|archive-url=https://web.archive.org/web/20190306043939/https://minerals.usgs.gov/minerals/pubs/commodity/niobium/mcs-2019-tanta.pdf|url-status=live}}</ref><ref>{{Cite web|url=https://www.statista.com/statistics/1271222/production-volume-of-niobium-in-nigeria/|title=Nigeria: Production volume of niobium|access-date=2 December 2021|archive-date=2 December 2021|archive-url=https://web.archive.org/web/20211202045325/https://www.statista.com/statistics/1271222/production-volume-of-niobium-in-nigeria/|url-status=live}}</ref>
|-
! scope="col" | Country
! scope="col" | 2000
! scope="col" | 2001
! scope="col" | 2002
! scope="col" | 2003
! scope="col" | 2004
! scope="col" | 2005
! scope="col" | 2006
! scope="col" | 2007
! scope="col" | 2008
! scope="col" | 2009
! scope="col" | 2010
! scope="col" | 2011
! scope="col" | 2012
! scope="col" | 2013
! scope="col" | 2014
! scope="col" | 2015
! scope="col" | 2016
! scope="col" | 2017
! scope="col" | 2018
! scope="col" | 2019
! scope="col" | 2020
|-
| style="text-align:left;"| {{flag|Brazil}} || 30,000 || 22,000 || 26,000 || 29,000 || 29,900 || 35,000 || 40,000 || 57,300 || 58,000 || 58,000 || 58,000 || 58,000|| 63,000|| 53,100|| 53,000|| 58,000|| 57,000|| 60,700|| 59,000|| 88,900|| 59,800 
|-
| style="text-align:left;"| {{flag|Canada}} || 2,290 || 3,200 || 3,410 || 3,280 || 3,400 || 3,310 || 4,167 || 3,020 || 4,380 || 4,330 || 4,420 || 4,630|| 5,000|| 5,260|| 5,000|| 5,750|| 6,100|| 6,980|| 7,700|| 6,800|| 6,500
|-
| style="text-align:left;"| {{flag|Australia}} || 160 || 230 || 290 || 230 || 200 || 200 || 200 || ? || ? || ? || ? || ?|| ?|| ?|| ?|| ?|| ?|| ?|| ?|| ?|| ?
|-
| style="text-align:left;"| {{flag|Nigeria}} || 35 || 30 || 30 || 190 || 170 || 40 || 35 || ? || ? || ? || ? || ?|| ?|| ?|| ?|| 29|| 104|| 122|| 181|| 150|| ?
|-
| style="text-align:left;"| {{flag|Rwanda}} || 28 || 120 || 76 || 22 || 63 || 63 || 80 || ? || ? || ? || ? || ?|| ?|| ?|| ?|| ?|| ?|| ?|| ?|| ?|| ?
|-
| style="text-align:left;"| {{flag|Mozambique}} || ? || ? || 5 || 34 || 130 || 34 || 29 || ? || ? || 4 || 10|| 29|| 30|| 20|| ?|| ?|| ?|| ?|| ?|| ?|| ?
|-
| style="text-align:left;"| {{flag|Democratic Republic of the Congo|name=Congo D.R.}} || ? || 50 || 50 || 13 || 52 || 25 || ? || ? || ? || ? || ? || ?|| ?|| ?|| ?|| ?|| ?|| ?|| ?|| ?|| ?
|-
| [[World]] || 32,600 || 25,600 || 29,900 || 32,800 || 34,000 || 38,700 || 44,500 || 60,400 || 62,900 || 62,900 || 62,900 || 63,000|| 50,100|| 59,400|| 59,000|| 64,300|| 63,900|| 69,100|| 68,200|| 97,000|| 67,700
|}

Lesser amounts are found in Malawi's Kanyika Deposit ([[Kanyika mine]]).