DESCRIPTION
Calcium Silicate occurs as a white to off-white, free-flowing powder that remains so after absorbing relatively large amounts of water or other liquids. It is a hydrous or anhydrous silicate with varying proportions of CaO and SiO2. It is manufactured by two distinct processes identified by the form of silica used, either diatomaceous earth or precipitated silica. Diatomaceous earth-based products are produced through hydrothermal reaction processes, which combine natural, or flux-calcined diatomaceous earth with hydrated lime to produce synthetic mineral forms of gyrolite and tobermorite. Precipitated or other silica-based products are produced by reacting sodium silicate and calcium oxide. It is insoluble in water, but it forms a gel with mineral acids. The pH of 1:20 aqueous slurry is between 8.4 and 12.5.