Editing Manganese (section)

== Production ==
{{see also|Manganese production by country}}
A significant proportion of the manganese ore mined, around 85% in the United States, is used in iron and [[steel]] production, such as in the production of [[ferromanganese]].<ref>{{cite web |author1=Ji-Eun Kim |title=Manganese Statistics and Information |url=https://www.usgs.gov/centers/national-minerals-information-center/manganese-statistics-and-information |website=USGS |publisher=National Minerals Information Center |access-date=23 April 2025 |language=en}}</ref> For the production of ferromanganese, the manganese ore is mixed with iron ore and carbon, and then reduced either in a blast furnace or in an [[electric arc furnace]].<ref name="IndMin">{{cite book|title=Industrial Minerals & Rocks: Commodities, Markets, and Uses |edition=7th|publisher=SME|date=2006|isbn=978-0-87335-233-8|chapter=Manganese|first=L. A.|last=Corathers |author2=Machamer, J. F. |chapter-url=https://books.google.com/books?id=zNicdkuulE4C&pg=PA631|pages=631–636}}</ref> The resulting ferromanganese has a manganese content of 30–80%.<ref name="Holl"/> Pure manganese used for the production of iron-free alloys is produced by [[Leaching (metallurgy)|leaching]] manganese ore with [[sulfuric acid]] and a subsequent [[electrowinning]] process.<ref name="hydrometI">{{cite journal|doi=10.1016/j.hydromet.2007.08.010 |title=Manganese metallurgy review. Part I: Leaching of ores/secondary materials and recovery of electrolytic/chemical manganese dioxide|date=2007|last=Zhang|first=Wensheng|author2=Cheng, Chu Yong|journal=Hydrometallurgy|volume=89 |pages=137–159|issue=3–4|bibcode=2007HydMe..89..137Z }}</ref>

[[File:Manganese Process Flow Diagram.jpg|thumb|upright=1.75|alt=Contains reactions and temperatures, as well as showing advanced processes such as the heat exchanger and milling process.|Process flow diagram for a manganese refining circuit]]
A more progressive extraction process involves directly reducing (a low grade) manganese ore by [[heap leaching]]. This is done by [[Percolation|percolating]] natural gas through the bottom of the heap; the natural gas provides the heat (needs to be at least 850&nbsp;°C) and the reducing agent (carbon monoxide). This reduces all of the manganese ore to manganese oxide (MnO), which is a leachable form. The ore then travels through a [[Mill (grinding)|grinding]] circuit to reduce the particle size of the ore to between 150 and 250 μm, increasing the surface area to aid leaching. The ore is then added to a leach tank of sulfuric acid and [[Iron(II)|ferrous iron]] (Fe<sup>2+</sup>) in a 1.6:1 ratio. The iron reacts with the [[manganese dioxide]] (MnO<sub>2</sub>) to form [[iron hydroxide]] (FeO(OH)) and elemental manganese (Mn).<ref name="ManganeseRecovery"/>

This process yields greater than 90% recovery of the manganese. For further purification, the manganese can then be sent to an [[electrowinning]] facility.<ref name="ManganeseRecovery">{{cite web|url=http://www.americanmanganeseinc.com/wp-content/uploads/2011/08/American-Manganese-Phase-II-August-19-2010-Final-Report-Internet-Version-V2.pdf|title=The Recovery of Manganese from low grade resources: bench scale metallurgical test program completed|date=2010|author=Chow, Norman|author2=Nacu, Anca|author3=Warkentin, Doug|author4=Aksenov, Igor|author5=Teh, Hoe|name-list-style=amp|publisher=Kemetco Research Inc.|url-status=dead|archive-url=https://web.archive.org/web/20120202065633/http://www.americanmanganeseinc.com/wp-content/uploads/2011/08/American-Manganese-Phase-II-August-19-2010-Final-Report-Internet-Version-V2.pdf|archive-date=2 February 2012}}</ref>