Which of the following method used for the concentration of copper pyrites?

Froth floatation process

The correct answer is option 3. Froth floatation process.

The method used for the concentration of copper pyrites is Froth floatation process.

Copper pyrites, also known as chalcopyrite, has the chemical formula \(CuFeS_2\). It is a sulfide mineral with metallic luster and brass-yellow color, often containing traces of gold and silver.

Froth flotation is based on the different wetting properties of the ore and the gangue particles. In this process, the finely ground ore is mixed with water to form a slurry. Collectors (like xanthates) are added to the slurry to increase the hydrophobicity of the desired mineral particles. Frothers (like pine oil) are added to create a stable froth. Air is blown into the slurry, and the hydrophobic particles attach to the air bubbles and rise to the surface, forming a froth layer. The froth, enriched in the desired mineral, is skimmed off from the surface, while the hydrophilic (water-attracting) gangue particles remain in the slurry and are discarded.

Froth flotation is particularly effective for sulfide ores, including copper pyrites, because these minerals naturally have good floatability. The process can selectively separate sulfide minerals from non-sulfide minerals and other impurities, enhancing the concentration of copper. This method is widely used in the mining industry for the concentration of copper ores, including chalcopyrite.