Electrolyzer shutdown: anode pure water penetration, cathode overflow
Thread Content
After the electrolytic cell is shut down, pure water is added to the anode every few hours; the addition of pure water stops once overflow occurs at the anode. Afterwards, the pure water in the anode chamber passes through the membrane and overflows at the cathode. Why is this? Shouldn’t the anode and cathode be at the same level? Why does only the cathode experience overflow after the addition of pure water stops? ? ?
Why is pure water added to the anode every few hours after parking, but not to the cathode? What is your liquid phase pressure difference? What is the gas phase pressure difference? How should I guess what the reason for your description is?
This indicates that the membrane has relatively large pinholes, and a drainage washing tank is used to test the membrane for leaks in order to confirm this.
Whether the system is stopped or not, water migration persists because the concentration of the catholyte remains high. After parking, the concentration of the catholyte decreases due to water migration; therefore, the cathode chamber needs to be circulated every few hours to maintain its concentration.
I guess the poster is referring to an osmotic pressure issue, where the side with lower concentration will penetrate into the side with higher concentration.
I really hadn’t paid attention before; I learned it now.
If the membrane is not damaged, it means that the concentration at the cathode is higher than that of the saline at the anode.