Abstract: The invention relates to a process for the preparation of superazeotropic hydrochloric acid from metal chloride solutions, e.g. spent pickling solutions. The process is characterized in that the metal chloride solutions are thermally decomposed with the formation of a hydrochloric gas, that the hydrochloric gas is processed in a manner known per se into a superazeotropic mixture of hydrogen chloride and water, the superazeotropic gas mixture being condensed to yield a superazeotropic hydrochloric acid. The invention further relates to a process for ore and/or metal processing employing superazeotropic hydrochloric acid prepared according to the invention.