Hydrogen and bromine production from concentrated sea-water

In salt production from sea-water, water is evaporated in open ponds and then crude salt is crystallized in crystallization ponds. The mother liqor from crystallization ponds; which is called bittern, is discharged back to the sea. Bromine concentration in bittern is approximately 1000 ppm which is fifteen times higher than in sea-water. In this study, bittern from the Izmir-Camalti salt production unit was electrolyzed to evolve bromine instead of chlorine at the anode by using special electrodes which had an overvoltage which avoided chlorine evolution. Under controlled cell potential, production of hydrogen at the cathode and pure bromine at the anode was achieved. (C) 1997 International Association for Hydrogen Energy.