At room temperature, sodium bromide is odourless, slightly bitter and highly toxic. It can absorb moisture easily and has high solubility in water but poor solubility in alcohol. Sodium bromide aqueous solution is neutral with electronic conductivity. The anhydrous sodium bromide crystal will be precipitated out at 51°C with dihydrate compound forming at temperature lower than 51 °C.
There are 2 methods of manufacturing sodium bromide:
Method 1: Urea reduction:
Sodium carbonate is added to urea in hot water and fed into the reactor. Bromine is gradually added into the reactor to generate sodium bromide. After which, the mixture is filtered, evaporated and crystallized and sodium bromide particles are separated and dried to obtain dry sodium bromide. The reaction is as follow:
3Br2 + 3Na2CO3 + NH2CONH2 → 6NaBr + 4CO2 + N2 + 2H2O
Method 2: Neutralization method:
Add about 40% hydrobromic acid into the reactor, stir and slowly add 40% caustic solution for neutralization to ph level of 7.5~8 to generate sodium bromide. After which, sodium bromide is obtained by filtering the mixture, evaporation, crystallization and separating the crystals out using a centrifuge. The reaction is as follows:
HBr + NaOH → NaBr + H2O
Photography Industry: Used for the preparation of liquid photosensitive film.
Medical Industry: Used to produce diuretics and sedatives.