Magnesium oxide

Magnesium oxide (CAS 1309-48-4), also known as magnesia or E530, is a high-temperature inorganic compound sourced from the calcination of magnesite or seawater-derived magnesium hydroxide.

Where is Magnesium oxide used?

• Steelmaking and cement: dead-burned magnesia grades line furnaces
• Agriculture: magnesium supplement to prevent grass tetany in livestock
• Food: anti-caking agent and acidity regulator
• Water treatment: neutralizes acidic effluents and stabilizes pH
• Pharmaceutical and cosmetic: antacid active and mild abrasive in oral care
• It offers stabilization without the sharp reactivity of lime.
• Used as a laxative for constipation.
• Used in replacement therapy for magnesium deficiency.

Good to know: Light-burned, hard-burned, and dead-burned forms are calcined at different temperatures to deliver distinct reactivity and surface area profiles.

Formulation notes

• Can interact with drugs whose absorption is pH-dependent.
• Light magnesium oxide has low bulk density and high specific surface area/reactivity, making it preferred in rubber and chemical applications.

Typical specification

• Magnesium oxide powder is available in purities from 94% to 99.6%.
• Magnesium oxide is available in technical, FCC, USP and EP grades.
• Magnesium oxide has high alkalinity and poor water solubility, which may require particle size control or suspension systems for homogeneous dispersion.

Regulatory status

• In the EU, magnesium oxide is added to food as E530 without quantity restrictions.
• Buyers should specify the required pharmacopoeia standard for magnesium oxide API, such as EP (Ph. Eur.), USP, JP, or BP.
• Magnesium oxide has ATC codes A02AA02, A12CC10, and A06AD02.
• Magnesium oxide is not classified as dangerous for transport (NONH).

Storage, packaging and handling

• Magnesium oxide requires protection from moisture during use and storage due to its low solubility and hygroscopicity.

Frequently asked questions about Magnesium oxide

What is the regulatory classification of magnesium oxide in Germany?

Magnesium oxide is classified as water hazard class 1 (WGK 1) in Germany.

Technical content is compiled and updated by the SoleChem product team from public technical sources; the certificate of analysis (COA) governs product-specific specifications.