Reactive Silica/Active Silica is silica which reacts with hydrofluoric acid. Reactive Silica is only used in phosphoric acid manufacturing plant when then reactive silica content is less in Rock Phosphate. When Rock phosphate reacts with Sulphuric Acid fluorine is evolved, reactive silica reacts with fluorine and Fluosilicic acid is formed which gets deposited in fuming chamber which is scraped and cleaned. When reactive silica content is less in rock phosphate fluorine is left free which corrugates the plant. To protect plant Reactive Silica is added externally in rock phosphate according to percentage require.
