Recently, the BBC released a radio broadcast on the element Bromine. You can access the full podcast here.
Bromine is part of the halogen group of the periodic table but it is probably not as well-known as other elements of this group such as fluorine (used in toothpaste), chlorine (used in swimming pools) and iodine (used in antiseptics).
Two chemists independently discovered bromine in the 19th century while studying naturally occurring salt waters: Carl Jacob Lowig (German) and Antoine Balard ( French). They crystallized the salts and saturated the remaining liquid with chlorine. What was left behind after distillation was a dark red liquid: bromine. Bromine derives its name from the Greek word “brōmos” meaning stench. Bromine atoms are highly reactive but you will never come across bromine in its elemental form. It is omnipresent in the environment (sea, soil, air) in inorganic compounds, known also as bromides, and in natural bromo-organic compounds. Today, bromine is extracted from salt lakes that are especially rich with the element, mainly the Dead Sea.
The earliest use of bromine was in medicines. But today, one of the biggest use of bromine is in fire safety. Fire is a self-perpetuating chemical reaction between oxygen and a fuel in the gas phase. Bromine interferes with the chemistry of the flame. Bromine-based flame retardants have the ability to release active bromine atoms (called free radicals) which effectively quench the chemical reactions occurring in the flame, reducing the heat generated and slowing down or even preventing the burning process. In other words, these active bromine atoms queue-jump the oxygen and bond with the fuel, making it inert. We are surrounded by products made out of flammable materials, such as oil-based plastics and synthetics. Brominated flame retardants increase a product’s resistance to fire. They make ignition more difficult and slow down the spread of fire allowing people to escape and making fire-fighters’ intervention easier. Have a look at our information sheet on Bromine and Fire safety here // MISSING LINK.
Another important use of bromine is in mercury capture. Coal burning power plants are a large source for mercury release in the environment. Bromine-containing compounds are added to the coal or to the flue gas to oxidize the mercury present in the coal. This process enhances the overall removal of mercury by downstream pollution control equipment.
Bromine is also used in swimming pools and industrial cooling water systems to purify and disinfect water, in agriculture to prevent pests from attacking stored grain, in tires to improve their physical properties and in many more applications.
Bromine: saving lives, creating possibilities