Method of operating a diaphragm electrolytic cell

Abstract

Described is a method for improving the operation of an electrolytic cell having an anolyte compartment, a catholyte compartment and a synthetic diaphragm separating the compartments, wherein liquid anolyte is introduced into the anolyte compartment and flows through the diaphragm into the catholyte compartment, which method involves introducing particulate material comprising halocarbon polymer short fiber, e.g., fluorocarbon polymer short fiber, into the anolyte compartment in amounts sufficient to lower the flow of liquid anolyte through the diaphragm into the catholyte compartment. In the case of an electrolytic cell wherein aqueous alkali metal chloride, e.g., sodium chloride, anolyte is introduced continuously into the anolyte compartment, thereby to produce a catholyte liquor containing alkali metal hydroxide and hypochlorite ion, the foregoing method is useful for decreasing the concentration of hypochlorite ion in the catholyte liquor and oftentimes increasing the concentration of alkali metal hydroxide in the catholyte liquor. Also describes adding at least one member chosen from halocarbon polymer microfibril, halocarbon polymer fiber, clay mineral, oxides and/or hydroxides of alkaline earth metals, and zirconium oxide/hydroxide in conjunction with the halocarbon polymer short fiber to the anolyte compartment, e.g., while the cell is operating.