REMOVAL OF BROMINE FROM GASEOUS HYDROGEN BROMIDE

摘要

A new, highly selective way of removing bromine contamination from a gaseous stream comprised of hydrogen bromide and bromine is described. Such process technology involves non-catalyzed free radical (benzylic) bromination of an alkylene- bridged aromatic hydrocarbon and/or certain alkyl-substituted aromatic hydrocarbons and recovering the purified gaseous HBr. Because of the high selectivity of the bromination on the aliphatic bridges or side-chains, virtually no ring bromination occurs, and this enables recovery of the bromine values in the form of HBr. Thus preferably, the bromine is recovered as HBr from the scrubbing liquid by subjecting the scrubbing liquid to thermal or catalytic dehyrobromination. In plant operations, the gaseous HBr purified in the process can then be introduced into a compressor to produce either liquid or gaseous HBr for storage under pressure. Alternatively, the purified gaseous HBr can be fed directly into one or more reactions in which HBr is used as a reactant.