Usage of Sodium silicate

Sodium silicate is used as the lead tube of buffer agent in domestic hot water system in the early 1920s. After hydrolysis in water, sodium silicate will generate the negatively charged colloidal particles. The particles migrate to the anode area forming a protective film. Protective film can form in the surface of cleaning metal and rust surface, but it is porous.

With the advantages of no poisonous and cheap, silicate has a corrosion inhibition to ball value, copper, aluminum and alloy. It can inhibit the brass's dezincification, but the dosage is higher than phosphate. So it is not suitable to be used in high hardness area of magnesium. The composite using of silicate and phosphate can improve the corrosion inhibition property.