Cambodia

Barium Carbonate

Extensively employed within the ceramics sector as a component in glazes, it functions as a flux, enabling the creation of distinctive colors that are challenging to achieve through alternative methods. In the brick, earthenware, and pottery industries, it is introduced to induce efflorescence.

Synonyms
Witherite
Chemical Formula
BaCO3
CAS Number
25070-31-9, 513-77-9

Characteristics

Molar Weight
197.335g/mol
Melting Point
811 °C
Boiling Point
1.360 °C
Density
4.275
Forms
Crystals, White

Uses and Applications

Key applications

  • Detergent
  • Building & Construction products
  • Paint and Coatings

Barium carbonate

Barium carbonate (BaCO3) is the carbonate of the alkaline earth metal barium. In nature, it occurs as the mineral ‘witherite’. The salt is used in the construction and paint industries, among others.

Properties

Barium carbonate is a chemical compound of barium, carbon and oxygen. The white, crystalline powder is odourless and practically insoluble in water, but decomposes in nitric and hydrochloric acid. At temperatures above 1,300 degrees Celsius, barium carbonate decomposes at atmospheric pressure to form barium oxide and carbon dioxide.
The salt is produced industrially at 40 to 90 degrees Celsius by the reaction of barium sulphide with carbon dioxide or sodium carbonate. The introduction of carbon dioxide into a slurry of barium hydroxide in water is another way of producing barium carbonate.
Mason worker plastering brick wall

Barium carbonate in the construction industry

Barium carbonate is used in the construction industry in the manufacture of building ceramics, tiles and bricks, among other things.
One of the main applications is the prevention of so-called efflorescence (formation of white, crystalline deposits on the surface due to soluble salts) in bricks and tiles to improve aesthetics.
For certain specialised applications, barium carbonate is used as an additive in cement and concrete. In this way, manufacturers achieve specific properties for their products, such as increased density or improved resistance to chemicals.
Barium carbonate also contributes ot he quality and durability of building materials: It improves the resistance of concrete and cement to so-called sulphate attacks. Sulphates can attack the structure of concrete and cause damage in certain environments, such as in soils with a high sulphate content or in sewers. The addition of barium carbonate reduces the risk of such damage as it reacts with the sulphates to form insoluble barium sulphate.

Barium carbonate in the paint and varnish industry

Barium carbonate is used in the paint and varnish industry primarily due to its properties as a filler and its reactivity. It is used as a filler in paints and varnishes to increase volume and reduce costs. Barium carbonate also serves as a carrier for pigments and optimises their dispersibility in paint and varnish mixtures. This achieves uniform colour distribution and intensity.
Barium carbonate also helps to increase the hardness and abrasion resistance of paints and varnishes. This improves the durability and resistance of coatings to mechanical stress and weathering.
As in the construction industry, barium carbonate reacts with sulphates in paints and varnishes and prevents the formation of undesirable efflorescence or other chemical reactions that could impair the quality of the coating.
Barium carbonate is used in special formulations for corrosion protection. It is used in anti-corrosion coatings to protect metals from oxidative and chemical attacks.
Barium carbonate is also used as a matting agent, which reduces the gloss of paints and varnishes and produces matt or satin surfaces.
Polymer applications

Barium carbonate in the polymer industry

Barium carbonate is mainly used as an additive and filler in the polymer industry. As a filler, it increases the volume and density of the material and improves the mechanical properties and thus its processability and flowability. The physical and chemical properties of polymers can also be modified by adding barium carbonate. This includes an increase in hardness, rigidity and abrasion resistance.
Barium carbonate also serves as a stabiliser to improve the thermal resistance of polymers. It helps to prevent the polymer from degrading at high temperatures during processing.
In certain polymers used in environments with high sulphate concentrations, barium carbonate increases the material's resistance to sulphate attack.
Due to ist high density, barium carbonate can be used in polymers developed for radiation protection applications. It increases the density ft he polymer and thus improves ist shielding properties against radiation.

Other areas of application for barium carbonate

Barium carbonate is used in the glass industry to clarify glass. It is also a component of special glass mixtures.
In metallurgy, barium carbonate is used to remove sulphur compounds from steel.
The salt produces green colours in fireworks. It is also used in pesticides such as rat poison.
In addition, the substance is the end product in the detection of carbon dioxide with barite water. It is also used in small quantities in the automotive industry for storage catalytic converters.
Barium carbonate serves as a starting material for the production of barium sulphate (BaSO₄) indirectly in the pharmaceutical industry. Barium sulphate is widely used in the pharmaceutical industry. It is mainly used as a contrast agent in radiology.