Contents

Potassium ethyl xanthate

Potassium ethyl xanthate

Names
Preferred IUPAC name Potassium O-ethylcarbonodithioate
Other names Potassium ethylxanthogenate Potassium ethylxanthate Potassium-O-ethyl dithiocarbonate
Identifiers
CAS Number	140-89-6 Y
3D model (JSmol)	Interactive image
ChEMBL	ChEMBL2380738
ChemSpider	8491 Y
ECHA InfoCard	100.004.946
EC Number	205-439-3
PubChem CID	2735045
UNII	1A6K3Y576K Y
CompTox Dashboard (EPA)	DTXSID6042315
InChI InChI=1S/C3H6OS2.K/c1-2-4-3(5)6;/h2H2,1H3,(H,5,6);/q;+1/p-1 Y Key: JCBJVAJGLKENNC-UHFFFAOYSA-M Y InChI=1S/C3H6OS2.K/c1-2-4-3(5)6;/h2H2,1H3,(H,5,6);/q;+1/p-1
SMILES [K+].[S-]C(=S)OCC
Properties
Chemical formula	CH3CH2OCS2K
Molar mass	160.29 g·mol−1
Appearance	Pale yellow powder
Density	1.263 g/cm3[1]
Melting point	225 to 226 °C (437 to 439 °F; 498 to 499 K)
Boiling point	decomposes
Acidity (pKa)	approximately 1.6
Hazards
GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H228, H302, H315, H319, H332, H335
Precautionary statements	P210, P240, P241, P261, P264, P270, P271, P280, P301+P312, P302+P352, P304+P312, P304+P340, P305+P351+P338, P312, P321, P330, P332+P313, P337+P313, P362, P370+P378, P403+P233, P405, P501
Related compounds
Other cations	Sodium ethyl xanthate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Y verify (what is YN ?) Infobox references

Chemical compound

Potassium ethyl xanthate (KEX) 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. It is a potassium salt of ethyl xanthic acid.

Production and properties[edit]

Xanthate salts are prepared by the action of alkoxidesoncarbon disulfide. The alkoxide is often generated in situ from potassium hydroxide:^[2]

CH₃CH₂OH + CS₂ + KOH → CH₃CH₂OCS₂K + H₂O

Potassium ethyl xanthate is a pale yellow powder that is stable at high pH, but rapidly hydrolyses below pH = 9:

CH₃CH₂OCS₂K + H⁺ → CH₃CH₂OH + CS₂ + K⁺

Oxidation gives diethyl dixanthogen disulfide:

4 CH₃CH₂OCS₂K + 2 H₂O + O₂ → 2 (CH₃CH₂OCS₂)₂ + 4 KOH

KEX is a source of ethylxanthate coordination complexes. For example (CH₃CH₂OCS₂)₃M have been prepared from KEX for M = Cr, In, Co.^{[clarification needed][3]}

Applications[edit]

Potassium ethyl xanthate is used in the mining industry as flotation agent for extraction of the ores of copper, nickel, and silver.^[4] 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 esters are useful intermediates in organic synthesis.^[5]

Safety[edit]

The LD₅₀ is 103 mg/kg (oral, rats) for potassium ethyl xanthate.^[4]

References[edit]