Sodium Bromide

Sodium bromide is extensively used medically as a hypnotic, anticonvulsant and a sedative. It is also used in conjunction with chlorine as a disinfectant for hot tubs and swimming pools.

Chemical Formula
NaBr
CAS Number
7647-15-6

Characteristics

Molar Weight
102.894g/mol
Melting Point
747 °C
Boiling Point
1,390 °C
Flash Point
800 °C
Density
3.21
Forms
White, Crystalline

Uses and applications

Key applications

  • Disinfectant
  • Medicines
  • Water treatment
  • Cleaning products
  • Petroleum production
  • Pharmaceuticals

General information about Sodium Bromide

Sodium bromide (NaBr) is the sodium salt of hydrobromic acid. It belongs to the halide group and is used in numerous industrial processes. Sodium bromide plays an important role in water treatment, energy production, the oil and gas industry and polymer chemistry in particular due to its chemical reactivity and stability.
Reaction with oxidising agents such as chlorine, sodium hypochlorite or ozone produces hypobromous acid - a powerful antimicrobial agent that efficiently kills bacteria, viruses, fungi and algae. Bromine-based disinfectants are considered to be more temperature- and pH-stable than chlorine-based alternatives and produce less odour, making them particularly attractive for industrial applications.
Properties of sodium bromide
Sodium bromide is a white, crystalline powder that dissolves well in water and ethanol. The aqueous solution is slightly acidic and hygroscopic, i.e. it attracts water.
Industrially, sodium bromide is produced by the reaction of sodium hydroxide (caustic soda) or sodium carbonate with hydrogen bromide. Alternatively, it is produced by reacting iron(II,III) bromide with sodium carbonate. After the reaction, crystallisation and drying take place to obtain pure sodium bromide.
Water being filled into treatment tank for hydrotesting

Sodium bromide in water treatment

In water treatment, sodium bromide serves as a disinfectant and biocide. Reaction with oxidising agents forms hypobromous acid, which has a broad antimicrobial spectrum of activity. Typical areas of application include:
  • Swimming pool maintenance: disinfection at high temperatures and pH values.
  • Industrial water treatment: control of microbial contamination in cooling towers and closed water systems.
  • Wastewater disinfection: use in sewage treatment plants for the hygienic treatment of purified wastewater.
  • Oil and gas production: prevention of biofouling in pipelines and tanks.
Sodium bromide is characterised in these applications by stable effectiveness under variable process conditions and lower odour development compared to chlorine compounds.
Hand of man wearing orange rubber gloves is use a hose to clean the tile floor.

Sodium bromide in the cleaning industry

In cleaning chemistry, sodium bromide is used in industrial cleaning agents and disinfectants. It helps to remove organic contaminants, biofilms and microorganisms that form on surfaces in production or cooling systems.
Due to its oxidative effect, sodium bromide contributes to increasing process hygiene and preventing microbial contamination.

Sodium bromide in the oil and gas industry

Sodium bromide is a key component in technical processes in oil and gas production. It is used in particular for the production of heavy fluids (drilling and settling fluids) that regulate the hydrostatic pressure in the borehole and prevent formation damage. Applications:
  • Drilling fluids: control of pressure and stability in the borehole.
  • Filling fluids: cleaning and preparation of the borehole for extraction.
  • Workover fluids: use in maintenance work on existing boreholes.
  • Corrosion protection: component of chemical formulations that protect metal parts in highly saline and corrosive environments.
Due to its high density, thermal stability and chemical inertness, sodium bromide is an efficient and safe component of modern drilling technologies.

Sodium bromide in the energy industry

In energy production, sodium bromide is used in various systems due to its chemical reactivity and stability. The main applications are:
  • Power plant water: biocide in cooling towers, heat exchangers and pipe systems to prevent biological fouling.
  • Zinc-bromine redox flow batteries: electrolyte in large-scale energy storage systems for wind and solar energy; enables reversible electrochemical reactions for efficient electricity storage.
  • Thermochemical storage: Component of materials that chemically store thermal energy and release it again when needed.
  • Mercury emission control: Additive in coal-fired power plants that oxidises elemental mercury, thereby facilitating its separation in filters.
In addition, sodium bromide is used in certain chemical processes in the energy industry, such as gas purification or hydrogen production.

Sodium bromide in the plastics and polymer industry

In polymer chemistry, sodium bromide acts as a catalyst, additive or reagent. Its applications extend to the manufacture, modification and stabilisation of numerous plastics; important applications include, for example:
  • Radical initiators: component of initiator systems in the radical polymerisation of polyethylene, polystyrene or polyacrylates.
  • Flame retardants: production of brominated polymers and additives for fire-retardant plastics, e.g. in electronic housings, construction products and vehicle parts.
  • Polymer modification: introduction of bromine atoms to improve chemical resistance, thermal stability and UV resistance.
  • Specialty polymers: use in membranes for fuel cells or water treatment, as well as in conductive or antimicrobial plastics.
Through these diverse applications, sodium bromide contributes significantly to improving the safety, performance and quality of modern polymer materials.

Summary

Sodium bromide is a versatile inorganic salt with high industrial relevance. Its importance ranges from water disinfection to drilling technology and energy production to polymer production.
The combination of chemical stability, antimicrobial effect and thermal resistance makes sodium bromide an indispensable auxiliary material in numerous industrial processes - especially those involving high temperatures, variable pH values or corrosive environments.