IMPROVED OPERATION AND REGENERATION OF PERMSELECTIVE ION-EXCHANGE MEMBRANES IN BRINE ELECTROLYSIS CELLS

摘要

Operating and regenerating a membrane-type electrolysis cell for prodn. of halogen and alkali from aq. brine comprises the following steps; (a) using as feed a brine which, immediately before becoming part of the anolyte, has a hardness(expressed as ppm(a) of 5ppm or less and a 'carbon oxide' content(as ppm CO2) of 70ppm or less; and (b) regenerating the membrane by contacting it on one or both sides with a soln. capable of dissolving the multivalent cation cpds. fouling the membrane, the soln. having a lower pH than that of the electrolyte during normal electrolysis.