Bromine prodn. from aq. acid bromide soln. - by treating with aq. hydrogen peroxide soln. and aq. bromate soln., giving high yield and purity

摘要

In the prodn. of pure Br2 by mixing aq. acid solns. contg. Br-ions with aq. H2O2 solns. and distilling the Br2 formed from the reaction mixt., the solns. are mixed at room temp. and then reacted at elevated temp., then the reaction is treated and reacted with an aq. alkali bromate soln. at least equiv. to the residual Br-ions at elevated temp. and the Br2 liberated is distilled from this mixt. Over 99% of the Br-ions in the soln., esp. a HBr absorption soln., can be recovered in the form of Br2 of high purity. In an example, Br2 was recovered in 99.5% yield from a 62% HBr soln. by Reacting with 35% H2O2 soln. for 2 h at 15-20 degrees C and 2 h at 40 degrees C, adding 25% NaBrO3 soln. and reacting 30 min. at 40 degrees C, then distilling off the Br2 formed.