Synthetic magnesium silicates are white, odorless, finely divided powders formed by the precipitation reaction of water-soluble sodium silicate (water glass) and a water-soluble magnesium salt such as magnesium chloride, magnesium nitrate or magnesium sulfate. The composition of the precipitate depends on the ratio of the components in the reaction medium, the addition of the correcting substances, and the way in which they are precipitated.
The molecular formula is typically written as MgO:XSiO2, where X denotes the average mole ratio of SiO2 to MgO. The product is hydrated and the formula is sometimes written MgO:XSiO2•H2O to show the water of hydration.
free-flowing white powder
Active Component (SiO2), %
Active Component (MgO), %
Loss on Drying (105°C, 2h), %
The very large active surface makes synthetic magnesium silicate useful for a wide variety of applications: purifying adsorbent (polyols, animal and vegetable oils, chromatography, dry cleaning, sugar, resins, odors); filler (rubber, ceramics, paper, glass, refractories); anti-caking agent (salt); catalyst; catalyst carrier; filter medium.