Question

How is a particular flux chosen for a particular metallurgical process?

Answer 1

A particular flux is chosen for a metallurgical process based on the nature of impurities in the ore:

1. If impurities are acidic (e.g., SiO₂, P₂O₅), a basic flux like CaO (lime) is used.
2. If impurities are basic (e.g., FeO, CaO), an acidic flux such as SiO₂ (sand) is chosen.
   The flux reacts with the impurities to form a fusible slag which floats over the molten metal and can be easily removed.