flotation, in mineral processing, method used to separate and concentrate ores by altering their surfaces to a hydrophobic or hydrophilic condition—that is, the surfaces are either repelled or attracted by water.

Why flotation is used for fine particles only?

Understanding the limits of fine particle flotation is the key to the selective separation of fine mineral particles. Fine particles have low collision efficiencies with gas bubbles and float slowly.

What is froth flotation process used for?

Froth flotation is used to raise the low mineral concentrations in ores to concentrations that can be more economically processed. A concentration of 25–30% is suitable for economical smelting of copper.