Debromination of Aqueous Chloride Solutions Using Ozone

The emission of bromine and chlorine into the gas phase during ozonation of acidic chloride solutions containing bromide ion impurities was investigated. The equilibrium composition of such solutions, additionally containing small amounts of chlorine and bromine compounds in oxidation states 0 and +1, was calculated. It was established that under oxidative conditions, the bromide ion is oxidized first. The main product is bromine chloride (BrCl), which exists in chloride solutions in equilibrium with the complex ion BrCl₂⁻ . Simultaneously, the slow oxidation of the chloride ion to Cl2 occurs. The kinetics of BrCl and Cl2 removal from the solution by a gas flow were studied. The possibility of using the BrCl₂⁻ ion formation reaction for the quantitative determination of Br– ions in chloride solutions was demonstrated.