Density 1.263 g/cm³ | Appearance Pale yellow powder | |
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Potassium ethyl xanthate is an organosulfur compound with the chemical formula CH3CH2OCS2K. It is a pale yellow powder that is used in the mining industry for the separation of ores. Unlike the related sodium ethyl xanthate, the potassium salt exists as an anhydrous salt.
Contents
Production and properties
Xanthate salts are prepared by the action of alcohols on carbon disulfide. The alkoxide is generated in situ from potassium hydroxide:
CH3CH2OH + CS2 + KOH → CH3CH2OCS2K + H2O
Potassium ethyl xanthate is a pale yellow powder that is relatively stable at high pH but rapidly hydrolyses at pH <9 at 25 °C. Unlike the sodium derivative, potassium xanthate crystallizes as the anhydrous salt and is nonhygroscopic.
Applications
Potassium ethyl xanthate is predominantly used in the mining industry as flotation agent for extraction of the ores of copper, nickel, and silver. The method exploits the affinity of these "soft" metals for the organosulfur ligand. Potassium xanthate is a useful reagent for preparing xanthate esters from alkyl and aryl halides. The resulting xanthate estes are useful intermediates in organic synthesis.
Safety
The LD50 is 683 mg/kg (oral, rats) for potassium ethyl xanthate.
