THREE-COMPARTMENT CELL WITH SELF-PRESSURIZED BUFFER COMPARTMENT

摘要

The invention describes a self-pressurized threecompartment membrane cell and a process for electrolyzing aqueous alkali metal halide solutions at low cell voltages and high cathode current efficiencies. Electrochemicallyactive electrodes are physically bondea to ion-exchange permselective membranes which divide the cell into three compartments. The mass transport characteristics of the membranes are selected so that water brought into the center or buffer compartment along with the halide ions tends to exceed water transport out of the compartment thereby to increase the pressure in the buffer compartment until equilibrium conditions are reached. This results in good electrode-to-current collector contact, as the electrochemically-active electrodes which are bonded to the membranes are forced against their corresponding current collectors.