Manganese dioxide

Manganese dioxide (CAS 1313-13-9) is an inorganic mineral compound used as a drying catalyst, pigment, and oxidizing agent.

Where is Manganese dioxide used?

• Coatings: drying agent in alkyd and oil-based systems
• Pigments: brown-black coloration
• Printing inks: black pigment and drying promoter for fast set times
• Personal care: hair coloring and oxidative cosmetic formulations
• Adhesives and sealants: curing accelerator in polysulfide-based systems
• It catalyzes oxidative polymerization of drying oils to reduce cure times and improve film hardness.
• Cathode material in alkaline batteries.
• Coloring of glass.
• Water treatment systems.

Good to know: Particle size and purity specifications vary significantly depending on the specific end-use application.

Formulation notes

• In reduction-fired glazes, 5% manganese dioxide yields tan-brown coloration.

Typical specification

• Dissolves in most glaze melts at small amounts, but around the 5% threshold it precipitates and crystallizes.
• Particle size of this grade is 44–75 microns.
• Maximum silicon dioxide content is 15%.
• At large amounts in a glaze, around 20%, metallic surfaces are likely.
• Decomposes above 553°C, producing manganese(III) oxide and oxygen.

Regulatory status

• EU occupational exposure limit (EU-OEL) for manganese dioxide as Mn, respirable fraction, is 0.05 mg/m³ as TWA.
• Not classified as a substance of very high concern (SVHC).
• Manganese and its compounds are not listed as substances subject to restriction under REACH Annex XVII.
• Specific migration limit for manganese from plastic materials and articles intended to come into contact with food is 0.6 mg/kg of food or food simulant.

Storage, packaging and handling

• Store away from combustible substances and reducing agents.
• Very stable at room temperature.

Frequently asked questions about Manganese dioxide

In which reactions is manganese dioxide used as a selective oxidant?

It is used in organic synthesis as a selective oxidant for alcohols, oxidising unsaturated alcohols such as benzylic, allylic and propargylic alcohols faster than saturated alcohols.

What particle size is available for nano-manganese dioxide?

Nano-manganese dioxide (HN-MnO2-50) has a particle size of 50 nm.

What is the solubility of manganese dioxide?

It is practically insoluble in water but soluble in inorganic acids.

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