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Pitting of 316L Stainless Containers From Bleach Due to Industrial Electrolysis of Sea Water

My company is designing hypochlorite (bleach) decontamination equipment to reduce the pitting corrosion of the required use of 316L stainless steel containers holding sea water for industrial sea water electrolysis. I am the design researcher and engineer. We wish to minimize this corrosion that occurs while the hypochlorite decomposing device is accomplishing its objective. 316L stainless steel is being used because of its excellent resistance to chloride ion of the sea water but it is still quite sensitive to attack by hypochlorite ion. It is desirable in our application not to switch from stainless steel to plastic containers as the plastic may be sensitive to ultraviolet light which is part of our technology. How can I protect the stainless steel - is there any satisfactory protective plating available? Can Cathodic Protection of the stainless steel container be used effectively? How does the hypochlorite break down the passivated chromium III oxide protective layer and attack the metals composing the stainless steel alloy, i.e., the chromium, iron, manganese, nickel etc.? Understanding the process chemically might shed some insight on solutions. Any suggestions would be most welcomed.

Reed Phillips Maryland
Product Designer and Researcher - Glen Cove, New York
May 16, 2009