METHOD OF ELECTROLYSIS OF AQUEOUS SOLUTION OF HYDROCHLORIC ACID Russian patent published in 2001 - IPC

FIELD: electrochemical industry; methods of electrolysis of aqueous solutions of hydrochloric acid. SUBSTANCE: proposed method is conducted in electrolyzers which consists of at least one electrochemical cell including cathode and anode chambers made from titanium or its alloys; zones of cracking of both chambers are covered with protective electrocatalytic coat. Cathode chamber includes gas-diffusion cathode; it is separated from anode chamber containing anode made from corrosion-resistant substrate with electrocatalytic coat for separation of chlorine and perfluorinated ion-exchange cation-type diaphragm. At least, gas-diffusion cathode and diaphragm are in close contact relative to each other. Cathode chamber is additionally provided with inlet hole for supply of oxygen-containing gas and outlet hole for discharge of reaction water. Anode chamber has inlet hole for aqueous solution of hydrochloric acid to be electrolyzed; maximum concentration of acid is 20%; anode chamber is also provided with outlet hole for removal of exhausted solution at temperature not exceeding 60 C and chlorine produced. Oxidizing compound is added to aqueous solution of hydrochloric acid whose redox potential is equal to zero on normal hydrogen electrode scale in starting and stopping of at least one electrochemical cell. EFFECT: enhanced mechanical reliability of electrolyzer; reduced capital outlays. 21 cl, 2 dwg, 1 ex