Process for regenerating hydrochloric acid from pickling plants

摘要

In order to reduce pollutants in the waste gas of regeneration plants for spent hydrochloric acid from pickling plants a process is provided, comprising the thermal decomposition of iron chloride in the spent pickling acid to iron oxide and gaseous hydrochloric acid, wherein to the spent pickling acid at least one compound is admixed which contains nitrogen having a low oxidation number, for example ammonium compounds, ammonia, urea or amides.