Precipitated silica is a relatively pure form of the mineral silica, which is produced by the chemical process known as precipitation. In chemical precipitation, a solid forms from a liquid due to a chemical reaction. Precipitated silica is formed by mixing solutions of sodium silicate with sulfuric acid in water. A chemical reaction occurs, and pellets of pure silica form.

The physical properties of the resulting silica can vary slightly depending on the exact conditions under which the precipitation reaction takes place. Changes in temperature, concentration of the solutions used, and the ratio of the ingredients in the mixture can all alter the physical properties of the silica particles. Manufacturers manipulate these conditions to change the size and porosity of the silica grains.

Applications

• Filler, softener and performance improvement in rubber and plastics

• Cleaning, thickening and polishing agent in toothpastes for oral health care

• Food processing and pharmaceuticals additive as anti caking, thickening agent, absorbent to make liquids into powders.

• Food rheology modifier

• Defoamer