Explain the froth floatation of concentrating ores.

In this method gangue is remove from sulphide ores. In this process, a suspension of the powdered ore is made with water. Suitable collectors and froth stabilizer are added. Collectors (e.g. pine oils, fatty acid, xanthates, etc) enhance non-wettability of the mineral particles and froth stabilize (e.g., cresols, aniline) stabilize the forth. The mineral particles wet by oils while the gangue particles by water. A rotating paddle agitates the mixture and draws air in it. As a result, froth is formed which carries the mineral particles. The froth is light and is skimmed off. It is then dried for recovery of the ore particles.