Sodium metasilicate

Sodium metasilicate (CAS 6834-92-0) is an inorganic sodium salt supplied as a white granular powder, commercially known under trade names including Simet A, Orthosil, Crystamet, and Crystamet. It carries no E-code designation and is distinct from liquid sodium silicate, commonly called water glass, though the two terms are sometimes used interchangeably in industry.

In water treatment, sodium metasilicate functions as a corrosion inhibitor by forming a protective silicate film on metal pipe surfaces, and as a coagulation aid that destabilises suspended particles for easier removal. In textile and paper processing, its high alkalinity drives saponification of fats and oils during scouring and pulp cleaning operations.

Sodium metasilicate is available in anhydrous and pentahydrate grades and is subject to REACH registration requirements for industrial supply within the EU. Buyers should confirm grade specification against intended application, as purity and hydration state affect both handling and performance. Standard packaging includes 25 kg bags and bulk quantities.