Antimony trioxide

Antimony trioxide is an inorganic compound with the formula Sb_2O_3. It is the most important commercial compound of antimony. Antimony trioxide is found in nature as the minerals valentinite and senarmontite. Like most polymeric oxides, Sb_2O_3 dissolves in aqueous solutions with hydrolysis.

Properties

Antimony trioxide is a white crystalline solid. It is insoluble in water but is soluble in acid solutions and alkalies. Antimony trioxide can be used as a flame retardant in combination with halogenated materials. The combination of the halogens and the antimony is effective in changing the molecular structure of the flame, thus inhibiting flame propagation.

Production

Antimony trioxide is produced by the oxidation of antimony metal or as a by-product of the smelting of antimony metal ores. The most common method of production is the oxidation of antimony metal in the presence of air. This process yields antimony trioxide directly. Alternatively, the roasting of antimony sulfide ores produces antimony trioxide as a by-product.

Uses

The primary use of antimony trioxide is as a flame retardant synergist in plastics, rubbers, textiles, and adhesives. It has also been used in white pigments, such as paint and paper. In the glass industry, it serves as a fining agent or as a degasser (to remove bubbles). Antimony trioxide is also used in the production of glass, ceramics, and enamels.

Health and Safety

Exposure to antimony trioxide can occur via inhalation, ingestion, or skin contact. The compound is considered to be a potential occupational carcinogen. The International Agency for Research on Cancer (IARC) has classified antimony trioxide as possibly carcinogenic to humans (Group 2B). Proper safety measures, including the use of personal protective equipment, are essential when handling antimony trioxide to minimize health risks.

Environmental Impact

Antimony trioxide can have adverse effects on the environment. It can contaminate water sources and soil, affecting aquatic life and potentially entering the food chain. Measures should be taken to prevent the release of antimony trioxide into the environment and to ensure safe disposal of waste containing this compound.