Corrosion issue of the frame in Asahi Kasei electrolyzers
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The last edit to this post was made by sunjl1981 on 2013-1-6 at 19:50. The frame of the Kyocera high-density natural circulation electrolysis cell is sealed by using glue and gaskets during use, resulting in a very small contact area with the electrolyte. The question is: Is there an anti-corrosion coating on the frame of the unit cell? If so, what is the coating? If not, will corrosion occur? The cases of the cathode and anode can be discussed separately. # ， ， &
The cathode hardly corrodes, while the anode does corrode
Finally, someone answered: Is there a coating on the frame of the anode in that new cell slot?
The frame of the unit cell anode is coated, while the cathode made of nickel does not have any anti-corrosion coating. The anode coating is made of palladium and extends about 2 centimeters wide from the inner edge of the frame. Since the inner edge of the anode’s rubber gasket is covered with a Teflon anti-corrosion gasket, corrosion generally does not occur. However, if the Teflon gasket is damaged and corrosive substances penetrate beyond the coating on the frame, the anode solution will cause corrosion of the frame
The anode plate is made of titanium, as is the frame – so why is it the frame that gets corroded by the anode solution?
Intergranular corrosion of free chlorine :P
It is caused by crevice corrosion at the seal. Some titanium equipment manufacturers also experience this phenomenon. It should have a coating for protection!
I’ve heard that hydrogen embrittlement can also cause corrosion, but I’m not familiar with the details. Please feel free to share your insights
Hydrogen embrittlement occurs only in an environment of high temperature and high hydrogen concentration. Additionally, the anode surfaces of new models of electrolytic cells now use titanium-palladium alloys instead of palladium coatings. This way, there is no need to replat with palladium when replacing the gasket later.