... rust remover for metal, reducing environmental po Sodium metasilicate pentahydrate is strongly alkaline, having strong capacity of ... for metal (zinc, aluminum, etc.). Therefore, sodium metasilicate pentahydrate is widely used for the manufacture of a variety ... , water retention agent, etc.PropertiesSodium metasilicate pentahydrate is an inorganic white powder or crystalline granules, non-toxic, ...