[Electrolysis of seawater, stainless steel anode, severe corrosion]
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This post was last edited by dadi520 on 2011-2-14 at 13:08. Hello brothers, I have some questions and would appreciate some answers. Thank you. The situation is as follows: Seawater is electrolyzed directly in flowing seawater, with a flow rate of 2 m/s. Anode: a certain type of stainless steel; Cathode: copper. “Due to certain limitations, we had no choice but to use stainless steel for the anode.” When 304L stainless steel is used as the anode, severe corrosion occurs—pitting corrosion and intergranular corrosion ensue; the material becomes brittle and turns black. The same problems occur when duplex steel 2205 or titanium is used! 317L is a bit better, but it still corrodes. In any case, corrosion does occur; however, there is a type of stainless steel that suffers very little pitting corrosion – the material simply thins evenly, and even after thinning it remains as shiny as new. But I have no idea which type of stainless steel it is. Can my friends help me figure it out? I’m extremely grateful!
Reply to 2# hui622: Is Monel okay? Should I add N or Mo? Thanks
Have you ever tried the iridium anode mesh?
I’ve learned it; take a look. Ordinary 304 steel will definitely suffer from severe corrosion
Reply to 4# zhulangcan: Thanks. No, but that one is quite expensive
Reply to 6# dadi520: There’s no way around it. Materials used in seawater electrolysis generally suffer from corrosion. It’s still a test of one-time investment
In electrolysis, at the anode, when using metal materials, is it possible to avoid corrosion? What is the electrode reaction of your anode? What is the electrode potential? Based on this, one must then select an appropriate anode material. This anode material is used for conducting electricity; if the wrong material is chosen, the result will be that one essentially “anodizes” oneself!
The corrosion resistance of stainless steel relies on passivation, which involves increasing the overpotential; however, in the case of electrolysis, increasing the overpotential is very detrimental
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The content above is worth considering.