A process for co-producing anhydrous hydrogen bromide and a purified bisulfate salt by (a) reacting a bromide salt with sulfuric acid to produce crude hydrogen bromide and crude bisulfate salt; (b) purifying the crude hydrogen bromide to produce anhydrous hydrogen bromide; and (c) removing bromide from the crude bisulfate salt to form a purified bisulfate salt. There are also provided improvements in the bisulfate purification and bromine removal, whereby bromine is removed from the system by a distillation process and the bromide is removed from the crude bisulfate via a spray drying process.