ENERGY CONSERVATION IN THE CHLORINE - ALKALI INDUSTRY
A small reduction in cell voltage of e.g. 150 mV on 3 V at a given current density represents a saving in electric energy of 5 %. The voltage of the cell is determined by the overvoltages at both electrodes with the main contribution coming from the cathodic overvoltage required for the hydrogen evolution. Two types of low overvoltage coatings based on (Ni,Co)S for the H-2 cathode and producing very active hydrogen evolution cathodes have been developed and tested in a chlorine - alkali environment. The electrodeposited and Teflon bonded coatings gave the results : +126 mV and +68 mV vs the Dynamic Hydrogen Electrode (D.H.E.) at 1 A/cm2, electrolyte 5 M NaOH, 80 degrees C, compared to over +350 mV for standard steel cathodes. The tests have also shown that the electrodes should not be left at open circuit when they are used in alkali solution. However, the addition of less than 0.1 M Na-2S to the NaOH electrolyte during open circuit regained the original performance of the oxidized NiS electrode.
Bibliographic Reference: EUR 10085 EN (1985), MF, 86 P., BFR 150, BLOW-UP COPY BFR 430, EUROFFICE, LUXEMBOURG, POB 1003
Availability: Can be ordered online
Record Number: 1989124047000 / Last updated on: 1987-01-01
Available languages: en