Ammonium hexafluorotitanate

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.

Ammonium hexafluorotitanate

Identifiers
CAS Number	16962-40-6 Y
3D model (JSmol)	Interactive image
ChemSpider	9496500
ECHA InfoCard	100.037.291
EC Number	241-036-9
PubChem CID	11321546
CompTox Dashboard (EPA)	DTXSID30937653
InChI InChI=1S/6FH.2H3N.Ti/h6*1H;2*1H3;/q;;;;;;;;+4/p-4 Key: NMGYKLMMQCTUGI-UHFFFAOYSA-J
SMILES [NH4+].[NH4+].F[Ti-2](F)(F)(F)(F)F
Properties
Chemical formula	F6H8N2Ti
Molar mass	197.935 g·mol−1
Appearance	white solid
Density	1.675g/cm3
Related compounds
Other anions	Hexafluorosilicate Hexafluorotitanic acid
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Synthesis

The compound is encountered in the extraction of titanium from its principal ore ilmenite: the ore is treated with excess ammonium fluoride:^[1]

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:

(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.^[2]