Application de l'electrode a poudre bipolaire au couplage de deux processus d'electrolyse

Abstract

Plate powder electrodes made from compressed activated carbon, allow the coupling of two electrolytic processes. The powder electrode is bipolar. Two electrolysers with different processes work in series, actuated by the same current. The coupled processes are such that hydrogen is produced on the face of the electrode serving as cathode and oxygen on the face serving as anode: the gasses are not formed free but are absorbed by the active carbon and afterwards react to form water. Thus the electrode retains its capacity to absorb hydrogen and oxygen indefinitely. Results obtained by the method for the simultaneous production of zinc and chlorine, copper and chlorine and zinc, chlorine and sodium hydroxide, are described. In all cases, energy consumption per unit mass of electrolysis product is relatively small. Thus, at 32°C, the simultaneous production of 1 Kg of zinc from zinc sulphate and 1·08 Kg of chlorine from 10% hydrochloric acid requires 2·68 KWh, and that of 1 Kg of copper from the sulphate and 1·005 Kg of chlorine from 10% hydrochloric acid requires 1·60 KWh. Analytical data on the passage of ions through the powder electrode, and potentiometric measurements, show that current passes through the electrode partly through the carbon grains and partly through the solution in the intergranular pores. The presence of oxygen on anodic and hydrogen on cathodic carbon grains is suggested.