Editing Platinum group (section)

== Production ==
[[File:PtMetalExtraction II.jpg|thumb|right|Process flow diagram for the separation of the platinum group metals.]]
The production of individual platinum group metals normally starts from residues of the production of other metals with a mixture of several of those metals. Purification typically starts with the anode residues of gold, copper, or nickel production. This results in a very energy intensive extraction process, which leads to environmental consequences. Carbon dioxide emissions are expected to rise as a result of increased demand for platinum metals and there is likely to be expanded mining activity in the [[Bushveld Igneous Complex]] because of this. Further research is needed to determine the environmental impacts.<ref>{{cite web|url=https://www.researchgate.net/publication/257673542|title=Anthropogenic Platinum Enrichment in the Vicinity of Mines in the Bushveld Igneous Complex, South Africa|last=Sebastien|first=Rauch|date=November 2012|access-date=14 February 2020}}</ref>  Classical purification methods exploit differences in [[chemical reactivity]] and [[solubility]] of several compounds of the metals under extraction.<ref name="Hunt2">{{cite journal|last=Hunt|first=L. B.|author2=Lever, F. M.|year=1969|title=Platinum Metals: A Survey of Productive Resources to industrial Uses|url=http://www.platinummetalsreview.com/pdf/pmr-v13-i4-126-138.pdf|journal=Platinum Metals Review|volume=13|issue=4|pages=126&ndash;138|doi=10.1595/003214069X134126138 |access-date=2009-10-02}}</ref>  These approaches have yielded to new technologies that utilize [[solvent extraction]].

Separation begins with dissolution of the sample.  If ''[[aqua regia]]'' is used, the chloride complexes are produced.  Depending on the details of the process, which are often trade secrets, the individual PGMs are obtained as the following compounds: the poorly soluble [[Ammonium hexachloroiridate|(NH<sub>4</sub>)<sub>2</sub>IrCl<sub>6</sub>]] and [[Ammonium hexachloroplatinate|(NH<sub>4</sub>)<sub>2</sub>PtCl<sub>6</sub>]], PdCl<sub>2</sub>(NH<sub>3</sub>)<sub>2</sub>, the volatile OsO<sub>4</sub> and RuO<sub>4</sub>, and [[Pentaamminechlororhodium dichloride|[RhCl(NH<sub>3</sub>)<sub>5</sub>]Cl<sub>2</sub>]].<ref name="Bernardis2">Bernardis, F. L.; Grant, R. A.; Sherrington, D. C. "A review of methods of separation of the platinum-group metals through their chloro-complexes" Reactive and Functional Polymers 2005, Vol. 65,, p. 205-217.  {{doi|10.1016/j.reactfunctpolym.2005.05.011}}</ref>

===Production in nuclear reactors===
{{main article|Synthesis of precious metals}}
Significant quantities of the three light platinum group metals—ruthenium, rhodium and palladium—are formed as [[fission product]]s in nuclear reactors.<ref>{{cite journal |url = http://www.technology.matthey.com/pdf/pmr-v14-i3-088-092.pdf |title=Platinum Metals from Nuclear Fission – an evaluation of their possible use by the industry |author=R. J. Newman, F. J. Smith |journal=Platinum Metals Review |volume=14 |issue=3 |year=1970 |pages=88|doi=10.1595/003214070X1438892 }}</ref> With escalating prices and increasing global demand, reactor-produced [[noble metal]]s are emerging as an alternative source. Various reports are available on the possibility of recovering fission noble metals from [[spent nuclear fuel]].<ref>{{cite journal |url=http://www.technology.matthey.com/pdf/pmr-v47-i2-074-087.pdf |title=Recovery of Value Fission Platinoids from Spent Nuclear Fuel; PART I: general considerations and basic chemistry |author=Zdenek Kolarik, Edouard V. Renard |journal=Platinum Metals Review |volume=47 |issue=2 |year=2003 |page=74|doi=10.1595/003214003X4727487 }}</ref><ref>{{cite journal |url=http://www.technology.matthey.com/pdf/79-90-pmr-apr05.pdf |doi=10.1595/147106705X35263 |title=Potential Applications of Fission Platinoids in Industry |year=2005 |last1=Kolarik |first1=Zdenek |last2=Renard |first2=Edouard V. |journal=Platinum Metals Review |volume=49 |pages=79 |issue=2|doi-access=free }}</ref><ref>{{cite journal |url=http://www.technology.matthey.com/pdf/pmr-v47-i3-123-131.pdf |title=Recovery of Value Fission Platinoids from Spent Nuclear Fuel; PART II: Separation process |author=Zdenek Kolarik, Edouard V. Renard |journal=Platinum Metals Review |volume=47 |issue=3 |year=2003 |page=123|doi=10.1595/003214003X473123131 }}</ref>