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A pure form of B2O3

U.S. Borax Boric Oxide is ideal when boric acid is required without alkali metals and moisture. This hard, glassy, granular product is water-soluble at a much slower rate than boric acid—and reacts exothermically when wetted. When exposed to the atmosphere, it slowly absorbs water, reverting to boric acid.

Boric oxide applications

What can our boric oxide do for you?

U.S. Borax Boric Oxide is a powerful tool in the production of specialty glasses, ceramics, enamels, and welding/soldering fluxes.

U.S. Borax Boric Oxide enhances industrial formulations

  • Reduces melting temperatures, increases thermal resistance and mechanical strength, and enhances aqueous and chemical durability in various glass formulations

  • Produces elemental boron in ceramic manufacturing

  • Acts as an excellent solvent for metallic oxides at high temperatures

  • Acts as a catalyst in the conversion and synthesis of many organic compounds, as well as in the preparation of boron halides, sodium borohydride, metallic borates, and borate esters

Boric Oxide

Borc oxide improves industrial processes and product performance

  • Increases the yields, strength, and scratch- and chemical-resistance of ceramic products

  • Binds magnesia-based refractory bricks

  • Stabilizes dolomite refractory bricks

Boric Oxide

Technical details

The normal glassy form of boric oxide has no definite melting point. It begins to soften at about 325 °C (617 °F) and subsequently flows above 450 °C (842 °F).

Boric oxide is a hygroscopic product. Avoid exposure to water or humidity, which can cause caking. If wetted, the project reacts exothermically, forming boric acid, so maintaining the integrity of the packaging is also essential.

Approximately 56.3 kg of boric oxide are the chemical equivalent of 100 kg of boric acid.

The reaction of boric oxide with water is highly exothermic.

Chemical and physical properties

› Molecular weight: 69.62

› Specific gravity: 1.84

› Appearance: Hard, glassy granules

› Melting point: 450 °C to 465 °C (842 °F to 869 °F)

› Stability: Hygroscopic; avoid exposure to water or humidity and maintain packaging integrity to prevent caking and the formation of boric acid.

Chemical composition (theoretical)

Boric oxide, B2O3: 100%

Containers: Products may be available in bulk, IBCs, or small bags

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