Australian Government: National Pollutant Inventory: Boron and compounds
Boron is an extremely valuable mineral and it is used in many products from cookware and medicine to nuclear waste storage and space exploration. Boron compounds are mainly used in borosilicate glass products, but are also used in agriculture, in fire retardants, and in soaps and detergents.
Boron is used in special-purpose alloys, in cementation of iron, as oxygen scavenger for copper and other metals, as fibres and filaments in composites with metals or ceramics, as semiconductor, for nuclear reactors, as a shield for nuclear radiation and in instruments used for detecting neutrons. Boron is used in pyrotechnic flares (distinctive green colour), for rockets (as an igniter), in boron-coated tungsten wires and in high temperature brazing alloys.
Applications for specific boron compounds follow.
Borates are used mostly to produce glass. They are also used in fire retardants, leather tanning industries, cosmetics, photographic materials, soaps and cleaners, adhesives and for high-energy fuel. Some pesticides used for cockroach control and some wood preservatives also contain borates.
Borax is used in soldering metals, as a cleansing flux in welding, in the manufacture of glazes and enamels (e.g. for covering steel of refrigerators and washing machines), in tanning, in cleaning compounds, to artificially age wood, as a preservative against wood fungus (either alone or with other antiseptics), and in fireproofing fabrics. It is also used for curing and preserving skins, in cockroach control and as a water softener in washing powders.
Boric acid is used for weatherproofing and fireproofing fabrics, as a preservative, in the manufacture of cements, crockery, porcelain, enamels, glass, borates, leather, carpets, hats, soaps, and artificial gems, and in nickel-plating baths. It is also used in the manufacture of cosmetics, in ointments and eye washes, as a mild antiseptic, in printing and dyeing, in photography, for impregnating wicks, for hardening steel, in welding flux, copper brazing, as an insecticide for cockroaches and carpet beetles, and in fungus control for citrus fruits.
Boron oxide is used in metallurgy, in the analysis of silicon dioxide in silicates, in blowpipe analysis, for the production of boron, in heat-resistant glassware, as a fire-resistant additive for paints, in electronics and as an herbicide.
Boron carbide is used as an abrasive, in the manufacture of hard and chemical-resistant ceramics or wear-resistant tools, in the refractory industry, in light weight cermets, in armour tiles, in radiation protection and shielding, in the nuclear industry in control rods in nuclear reactors (high capture cross-section to absorb thermal neutrons), as raw material for producing other boron containing materials (e.g. titanium boride), and in solid fuel (propellant for ducted rockets).
Boron nitride is used as a refractory material, laboratory reagent, and abrasive. Boron trichloride is used in the manufacture and purification of metal alloys, in bonding of iron and steel, in soldering fluxes, and in the manufacture of electrical resistors. It is also used to extinguish magnesium fires in heat resisting furnaces.
Boron trifluoride is widely used to promote various organic reactions. Boron filaments are high-strength, lightweight materials that are used in fibre optics research and for advanced aerospace structures.