Potassium Ethyl Xanthate, Potassium O-ethyl Dithiocarbonate, Potassium Ethyl Xanthogenate, Potassium Ethyl Dithiocarbonate, KEX, 140-89-6

Potassium Ethyl Xanthate, Potassium O-ethyl Dithiocarbonate, Potassium Ethyl Xanthogenate, Potassium Ethyl Dithiocarbonate, KEX, 140-89-6

Chemical Identity

• Name: Potassium Ethyl Xanthate

• CAS No: 140-89-6

• Formula: C₃H₅OS₂K

• Appearance: Pale yellow powder or pellets, sometimes liquid formulations.

• Molar Mass: ~160.29 g/mol

• Density: ~1.26 g/cm³

• Melting Point: ~225–226 °C (decomposes before boiling)

Mechanism of Action in Flotation

• KEX is a collector reagent used in mineral flotation.

• It adsorbs onto the surface of sulfide minerals (copper, zinc, lead) and makes them hydrophobic, enabling attachment to air bubbles.

• Compared to Sodium Ethyl Xanthate (SEX), the potassium salt form is more stable and often preferred for storage and handling.

• Its short ethyl chain provides high selectivity, making it suitable for ores where precision separation is needed.

Applications

• Copper ores → chalcopyrite and other copper sulfides.

• Zinc ores → sphalerite, often with activators like copper sulfate.

• Lead ores → galena flotation.

• Mixed sulfide ores → when selective separation is required.

Advantages

• High selectivity → reduces unwanted mineral recovery.

• Stable potassium salt → better shelf life compared to sodium form.

• Versatile forms → available as powder, pellets, or liquid, adaptable to different processing setups.

Limitations

• Lower collecting strength compared to longer-chain xanthates (like PAX).

• Not ideal for refractory ores where stronger collectors are needed.

• Environmental concerns → degradation can release carbon disulfide (CS₂), which is toxic.

Xanthate – Sectoral Suitability Table