Ammonium hexafluorotitanate
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| ImageFile = (NH4)2TiF6.svg
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| Section1 = {{Chembox Identifiers
| CASNo = 16962-40-6
| CASNo_Ref = {{Cascite|correct|CAS}}
| ChemSpiderID = 9496500
| EC_number = 241-036-9
| PubChem = 11321546
| SMILES = [NH4+].[NH4+].F[Ti-2](F)(F)(F)(F)F
| StdInChI=1S/6FH.2H3N.Ti/h6*1H;2*1H3;/q;;;;;;;;+4/p-4
| StdInChIKey=NMGYKLMMQCTUGI-UHFFFAOYSA-J
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| Section2 = {{Chembox Properties
| H=8 | Ti=1 | F=6|N = 2
| MolarMass =
| Appearance = white solid
| Density = 1.675g/cm3
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| Section3 = {{Chembox Hazards
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| Section8 = {{Chembox Related
| OtherAnions = Hexafluorosilicate
Hexafluorotitanic acid
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Ammonium hexafluorotitanate is the inorganic compound with the chemical formula (NH4)2[TiF6]. A colorless salt, the compound consists of ammonium ions and the hexafluorotitanate dianion.
Synthesis
The compound is encountered in the extraction of titanium from its principal ore ilmenite: the ore is treated with excess ammonium fluoride:{{cite book |doi=10.1002/9780470132364.ch22|chapter=Extraction of Titanium(IV) Oxide from Ilmenite |year=1957 |last1=Bichowsky |first1=Foord Von |title=Inorganic Syntheses |pages=79–82 |isbn=9780470132364|volume=V }}
::{{chem2|FeTiO3 + 10 NH4F -> (NH4)2FeF4 + (NH4)2TiF6 + 6 H2O}}
After removal of iron impurities, the titanium is recovered as a hydrated titanium dioxide by treatment of the aqueous extract of the hexafluoride with ammonia:
::{{chem2|(NH4)2TiF6 + 4 NH3 + 2 H2O -> TiO2 + 6 NH4F}}
Structure
Many salts of hexafluorotitanate have been characterized by X-ray crystallography. In the lattice [TiF6]2- octahedra interact with the ammonium cations by hydrogen bonds.{{cite journal |doi=10.1107/S0567740882007195|title=Hydrogen bonding in Diammonium Hexafluorotitanate |year=1982 |last1=Tun |first1=Z. |last2=Brown |first2=I. D. |journal=Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry |volume=38 |issue=6 |pages=1792–1794 |bibcode=1982AcCrB..38.1792T }}
References
{{Inorganic-compound-stub}}
{{fluorine compounds}}
{{titanium compounds}}