7643. Potassium Iodide

Nomenclature

CAS number: 7681-11-0
Potassium iodide (KI); Jodid (Merck KGaA); Thyroblock (Horner); Thyrojod (Henning).
IK; mol wt 166.00.
I 76.45%, K 23.55%.
KI.

Description and references

Potassium iodide of commerce contains about 99.5% KI. Prepd from HI and KHCO3. Purification by melting in dry hydrogen: Lingane, Kolthoff, Inorg. Synth. 1, 163 (1939). Continuous electrolytic process for large scale industrial prepn: Morylott, Elkins, US 2989450 (1961 to Dow). Toxicity data: Hildebrandt, Arch. Exp. Pathol. Pharmakol. 96, 292 (1923). Use in the treatment of radiation poisoning resulting from a nuclear accident: W. K. Waterfall, Br. Med. J. 281, 988 (1980); Bull. N.Y. Acad. Med. 57, 395 (1981).

Properties

Colorless or white, cubical crystals, white granules, or powder. Slightly deliquescent in moist air; on long exposure to air becomes yellow due to liberation of iodine, and small quantities of iodate may be formed; light and moisture accelerate the decompn. Aq solns also become yellow in time due to oxidation, but a small amount of alkali prevents it. d 3.12. mp 680° (volatilizes at higher temp). One gram dissolves in 0.7 ml water, 0.5 ml boiling water, 22 ml alcohol, 8 ml boiling alcohol, 51 ml abs alcohol, 8 ml methanol, 75 ml acetone, 2 ml glycerol, about 2.5 ml glycol. Potassium iodide solns readily dissolve elemental iodine. The aq soln is neutral or, usually, slightly alkaline. pH: 7-9. 30 g KI with 21 ml water gives 30 ml of a saturated soln at 25°. Approx LD i.v. in rats: 285 mg/kg (Hildebrandt). Incompat. Alkaloidal salts, chloral hydrate, tartaric and other acids, calomel, potassium chlorate, metallic salts.

Use

Manuf photographic emulsions; in animal and poultry feeds to the extent of 10-30 parts per million; in table salt as a source of iodine and in some drinking water; also in analytical chemistry for iodometric titrations. Reducing agent.

Therapeutic Category

Antifungal; expectorant; iodine supplement.

Therapeutic Category (Veterinary)

In actinobacillosis, actinomycosis. For simple goiter. As expectorant. In iodine deficiency and in chronic poisoning with lead or mercury. Orally only, not by injection. Externally for treatment of bursal enlargements.

Keywords

Antifungal (Synthetic); Expectorant; Replenishers/Supplements; Iodine