Bromine salt is present in sea water and is recovered from water in brine wells and out of the Dead Sea. The salt of bromine, bromide, is collected out of seawater by treating the seawater with a chlorine gas and then flushing the seawater and chlorine gas with air; the result of the reaction causes bromide to be oxidized to bromine. This process is used for large scale bromine isolation purposes.
Bromine can be isolated on a small scale laboratory setting by reacting solid sodium bromide salt with sulphuric acid. From this reaction, bromine gas is formed; additional amounts of sulphuric acid will oxidize the bromine gas to form pure bromine and sulfur dioxide. This reaction will only work with sodium bromide salt; it will not work if using the bromide salt containing chlorides or fluorides.
Pure bromine is toxic when inhaled and is corrosive to human tissue; this element must be handled carefully in its isolated form.