Hydrogen assisted magnesiothermic reduction

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The hydrogen assisted magnesiothermic reduction ("HAMR") process is a thermochemical process to obtain titanium metal from titanium oxides. [1] [2]

A technical challenge in the production of titanium metal is the formation of oxide impurities. The Kroll process, which is widely used commercially, addresses this challenge by converting titanium ore (an oxide) into titanium tetrachloride (TiCl4). This intermediate is readily purified. It is reduced to titanium metal with magnesium. This technology is both capital, energy, and carbon-intensive. One advantage of the Kroll process, and several like it, is that it starts with titanium ores (e.g., illmenite), not a purified dioxide.

The HAMR technology also entails a two step process, starting with TiO2 under an atmosphere of hydrogen gas. The product TiH2 can be further processed to titanium metal through standard methods. The reduction of titanium oxides to titanium metal using magnesium does not occur. The novelty of the HAMR process is the inclusion of hydrogen. [3]

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<span class="mw-page-title-main">Ilmenite</span> Titanium-iron oxide mineral

Ilmenite is a titanium-iron oxide mineral with the idealized formula FeTiO
3
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<span class="mw-page-title-main">Zirconium dioxide</span> Chemical compound

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<span class="mw-page-title-main">Titanium dioxide</span> Chemical compound

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2
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<span class="mw-page-title-main">Niobium dioxide</span> Chemical compound

Niobium dioxide, is the chemical compound with the formula NbO2. It is a bluish-black non-stoichiometric solid with a composition range of NbO1.94-NbO2.09. It can be prepared by reducing Nb2O5 with H2 at 800–1350 °C. An alternative method is reaction of Nb2O5 with Nb powder at 1100 °C.

The +4 oxidation state dominates titanium chemistry, but compounds in the +3 oxidation state are also numerous. Commonly, titanium adopts an octahedral coordination geometry in its complexes, but tetrahedral TiCl4 is a notable exception. Because of its high oxidation state, titanium(IV) compounds exhibit a high degree of covalent bonding.

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References

  1. Xia, Yang; Fang, Z. Zak; Zhang, Ying; Lefler, Hyrum; Zhang, Tuoyang; Sun, Pei; Huang, Zhe (2017). "Hydrogen Assisted Magnesiothermic Reduction (HAMR) of Commercial TiO2 to Produce Titanium Powder with Controlled Morphology and Particle Size". Materials Transactions. 58 (3): 355–360. doi: 10.2320/matertrans.MK201628 .
  2. Xia, Yang; Lefler, Hyrum D.; Zhang, Ying; Sun, Pei; Fang, Zhigang Zak (2020). "Hydrogen Assisted Magnesiothermic Reduction (HAMR) of TiO2 to Produce Titanium Metal Powder". Extractive Metallurgy of Titanium. pp. 165–179. doi:10.1016/b978-0-12-817200-1.00009-0. ISBN   9780128172001. S2CID   213342922.
  3. "asx.com.au, "TAO TO EXPLORE COMMERCIALIZATION OF LOW-CARBON, LOW-COST TITANIUM METAL POWDER IN THE USA"".