As a multi-functional additive, what are the benefits of magnesium silicate?

Magnesium silicate is widely used as an anti-caking agent, adsorbent, and filler in food, pharmaceuticals, and cosmetics. It helps water treatment, prevents clumping in powdered products, aids in tableting, acts as an antacid, and is used to purify oils and remove impurities.

Adsorption

Magnesium silicate (MS) has been used for contaminant treatment due to its good adsorption capacity. To date, various kinds of magnesium silicate with unique structures and morphologies have been successfully prepared and used for wastewater treatment. Generally, a larger specific surface area corresponds to more adsorption sites to make the adsorbent have higher adsorption capacity. Much work has been done to control the surface morphology of MS to improve its adsorption capacity.Materials with hierarchical structure have broad application in adsorption, separation and purification, catalysis, sensor and electrochemistry due to their structures characteristics. Researchers prepared the mesoporous MS having hierarchical structure by hydrothermal process using mesoporous silica filled with carbon (C@SBA-15) as both silica source and assisted template, reported adsorption capacity of MB to be 382 mg/g^[1].

In the cosmetics industry, magnesium silicate's strong adsorption properties make it an ideal ingredient for pressed powder, loose powder, and oil-control creams, as it can absorb excess oil and keep makeup matte and dry for a long time.

Stability

Magnesium silicate is largely insoluble in water, but it can form colloidal dispersions. Magnesium silicate hydrate (M-S-H) phases, used in cements, show good stability and are stable in hydrated forms. It is highly stable, practically insoluble in water and organic solvents, and maintains structural integrity in cool, dry, well-closed containers^[2].

Safety

Magnesium silicate is generally classified as a GRAS (Generally Recognized As Safe) substance by the U.S. Food and Drug Administration (FDA), and is therefore commonly used as a food additive (anti-caking agent) and a cosmetic ingredient. However, excessive inhalation of dust may damage the respiratory system.

References

[1] Sun, Z., Srinivasakannan, C., Liang, J., Duan, X. (2019). Preparation of hierarchical magnesium silicate with excellent adsorption capacity. Ceramics International, 45 4, Pages 4590-4595. https://doi.org/10.1016/j.ceramint.2018.11.146

[2] House, K. L., Hao, Z., Liu, Y., Pan, L., O'Carroll, D. M., Xu, S. (2021). The integrity of synthetic magnesium silicate in charged compounds. Scientific Reports, 11 1, 23717. https://doi.org/10.1038/s41598-021-02930-8