A method and a device for producing hydrochloric acid by contacting a hydrochloric-acid-containing gas with an aqueous washing liquid are disclosed. A chloride-forming substance is added to the washing liquid, so that the hydrochloric acid in the gas not only is bound by the chloride-forming substance as a chloride salt, but also is absorbed by the washing liquid as 'free' hydrochloric acid. Optionally, the washing liquid is then concentrated by stripping of water. Subsequently, sulphuric acid is added to the washing liquid to drive off hydrochloric acid from the chloride salt. Finally, hydrochloric acid is distilled from the washing liquid. The device includes a scrubber (1) having inlets (2, 10, 11, 12) and outlets (5, 13), a distillation unit (25) having inlets (27, 24) and an outlet (29), and optionally an evaporation unit (14) having an inlet (16) communicating with the scrubber outlet (13), and an outlet (24) communicating with the distillation-unit inlet.
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