GB585728A - Improvements in or relating to the recovery of bromine from hydrogen bromide - Google Patents

Abstract

Hydrogen bromide mixed with an oxygen-containing gas in a volume ratio of oxygen to hydrogen bromide exceeding one to four is passed through a reactor at 800-1200 DEG C. and preferably at 800-1000 DEG C. to recover bromine. The excess oxygen-containing gas preferably suffices to absorb the heat of reaction. An oxidation catalyst, e.g., cerium oxide on refractory support, e.g., pumice or silica may be used. In the presence of, e.g., excessive diluent steam, the reaction temperature may be maintained by an admixture of combustible gas, e.g., hydrogen. Residual oxygen gases after bromine removal may be recycled to the reactor to maintain a 4 to 5 times excess. As shown the gas mixture catalysed in the reactor 1 and cooled by a water spray in the cooler 7, passes to the condenser 10 and scrubber 12 where it is scrubbed by, e.g., sodium bromide solution. Gas discharged at 13 is recycled to the reactor. The condenser and scrubber condensates are stripped of bromine in the fractionating column 11 and the <PICT:0585728/III/1> bromide liquor recycled to the scrubber. The bromine passes to a condenser 17 and separator 18, the liquid bromine being removed and the bromine water recycled to the spray cooler 7. Unreacted hydrogen bromide in the effluent reactor gas is converted to bromine by adding chlorine at 20. The Provisional Specification discloses the use of a 700-1200 DEG C. temperature range. U.S.A. Specification 2,163,877 is referred to.