Abstract: Electrolyzer for the extraction of a substance from an electrolytic bath.The electrolyzer comprises an anode and a cathode immersed in the bath. The cathode, in which the substance is formed, surrounds the anode. The electrolyzer also comprises means for confining the substance in the vicinity of the cathode and for guiding said substance along and towards the upper end of the cathode, together with means for collecting the substance at said end. These confinement and guidance means comprises at least one grid layer located in the vicinity of the cathode and passing along the same.Application to the production of alkaline metals or alkaline earth metals.

Abstract: A horizontal electrolyzer comprises a mercury cathode, an anode located above the cathode and an inclined diaphragm separating the cathode from the anode, the cathode, diaphragm and anode being substantially parallel. The cathode consists of mercury flowing longitudinally in a plurality of channels which are vertically offset with respect to each other.