Which substance is used as a stabilizer in the froth flotation process?

In the froth flotation process, the objective is to separate valuable minerals from the ore through selective adhesion to air bubbles. A stabilizer plays a crucial role in ensuring that the froth formed is stable, allowing the valuable minerals to remain buoyant while the unwanted materials sink.

Aniline, which is an organic compound, acts as a reagent in the flotation process as it can alter the surface properties of minerals, enhancing their ability to attach to air bubbles, and thereby helping to stabilize the froth. By modifying the hydrophobicity of the minerals, aniline promotes the formation of a more stable froth, which is essential for effective separation.

Other substances listed have different roles: starch, for instance, is commonly used in mineral processing but primarily functions as a depressant rather than a stabilizer. Sodium carbonate adjusts pH levels, thus impacting the flotation process indirectly, while calcium sulfate is generally involved as a reagent for other chemical purposes but does not primarily act in enhancing froth stability.

Overall, the role of aniline in modulating surface interactions makes it a suitable stabilizer in the froth flotation process.