Patent ID: 7128824

Claim:
A method for the electrolysis of aqueous solutions of hydrogen chloride in order to produce chlorine, wherein the following process parameters are maintained for initial operation: the anode half-element is filled with a 5 to 20% strength by weight hydrochloric acid that contains at least 1 mg/l of free chlorine, the concentration of the hydrochloric acid is at least 5% by weight during initial operation, the volumetric flow of the hydrochloric acid through the anode half-element is set in such a way that, at the start of electrolysis, the velocity of the hydrochloric acid in the anode space is from 0.05 cm/s to 0.15 cm/s, the electrolysis is started with a current density of 0.5 to 2 kA/m 2 , and the current density is then increased continuously or discontinuously until the desired current density is reached.