7610. Potassium Bifluoride

Nomenclature

CAS number: 7789-29-9
Potassium acid fluoride; potassium hydrogen fluoride.
F2HK; mol wt 78.10.
F 48.65%, H 1.29%, K 50.06%.
KF.HF.

Description and references

Prepd according to the eq KOH + 2HF = KHF2 + H2O: Lange, Eichler, Z. Phys. Chem. 129, 285 (1927); Kwasnik in Handbook of Preparative Inorganic Chemistry vol. 1, G. Brauer, Ed. (Academic Press, New York, 2nd ed., 1963) p 237. Made commercially from potassium carbonate and hydrofluoric acid.

Properties

Tetragonal crystals. Poisonous. d 2.37. mp 238.7°. Transformation pt 195°. Soly in water (g/100 ml): 30.1 (10°); 39.2 (20°); 114.0 (80°). Sol in dil alc. Insol in abs alc.

Caution

Corrosive and irritating to skin, mucous membranes.

Use

In the prepn of pure potassium fluoride; as an electrolyte in the manuf of fluorine; frosting glass; treating coal to prevent slag formation; flux for silver solders; catalyst in the alkylation of benzene with olefins.