Hydrochloric acid purification process

A process for treating a gas stream comprising hydrochloric acid, hydrofluoric acid and fluorinated/oxygenated compounds, comprising successively subjecting the gas stream to the following stages:

• a stage of catalytic hydrolysis;
• a stage of washing with an acid solution;
• a stage of adsorption of impurities by active charcoal;
• and
• a stage of adiabatic or isothermal absorption of the hydrochloric acid in an aqueous solution, thereby making it possible to collect hydrochloric acid solution.

A plant for the treatment of a gas stream comprising hydrochloric acid, hydrofluoric acid and fluorinated/oxygenated compounds, comprising:

• a pipe for feeding a gas stream comprising hydrochloric acid, hydrofluoric acid and fluorinated/oxygenated compounds to a catalytic hydrolysis unit;
• a washing unit, fed, on the one hand, by a pipe for collecting the hydrolyzed gas stream resulting from the catalytic hydrolysis unit and, on the other hand, by a pipe for introducing an acid solution;
• a unit for adsorption of impurities comprising a bed of active charcoal, which unit is fed by a pipe for collecting the washed gas stream resulting from the washing unit;
• a unit for adiabatic or isothermal absorption, fed, on the one hand, by a pipe for collecting the purified stream resulting from the adsorption unit and, on the other hand, by a pipe for introducing an aqueous solution;
• and
• a pipe for collecting a hydrochloric acid solution at the outlet of the adiabatic absorption unit.