Blackening of the anode outlet hose and excessive acidity in the primary brine

When filling the tank while the vehicle is in operation, the intrusion of chlorinated brine or chlorine will have no effect on the anode coating, but it may affect the cathode coating, as brine containing free chlorine exhibits a strong electrolytic effect in the battery. As for the discoloration of the anode outlet hose, it cannot be explained. If acidic brine is fed into the cell, it will cause the levels of calcium and magnesium ions to exceed acceptable limits significantly; the ion exchange membrane is likely to be damaged. Check the purity of chlorine gas at the cell’s outlet.

When chlorine enters the electrolyzer, it corrodes the cathode coating, causing the coating to peel off and the hoses to darken; however, it has no effect on the anode； We have only encountered the phenomenon of the cathode hose turning black; we have not seen the cathode hose turn black ； Saline entering the cell that is acidic, as well as prolonged exposure to such conditions, can reduce the service life of the ion exchange membrane and lower current efficiency.

Thank you for your responses. What I mainly want to know is why an overly acidic brine, when introduced into the tank, causes the tank temperature to rise, as well as why the pH of the fresh brine at the outlet increases. Some of our colleagues say that the rise in tank temperature is due to an increase in side reactions, but adding acid to the brine should suppress such side reactions; therefore, the pH of the fresh brine at the outlet should decrease, yet in our case it increases.

Excessively high tank temperature indicates too many side reactions at the anode. The high pH of weak saline water is due to intensified OH reverse osmosis across the ion membrane

The impurities deposited on the ion membrane are dissolved by the acidic saline you add, and likewise, the impurities and coating on your cell tank are also dissolved by the acidic saline. Although that is the case, there are still significant drawbacks. Ion membranes cannot withstand such strong acidity, and the coating on the anode is even less able to tolerate it. I wonder how long such strongly acidic brine has been circulating in the electrolyzer, and what the trend of the cell voltage is – whether it remains constant, doesn’t change, or increases slightly. One last thing I’d like to know is whether by \"turning black\" you mean that there is a black, powdery deposit on the anode outlet hose.

Once, the pH of the brine was too low, which caused calcium and magnesium to be washed off from the resin tower and carried into the electrolyzer. Good heavens, that was a quite serious production accident. . .

6# 181128425: After acidic saline was introduced, about ten hours passed, and the tank voltage neither increased nor decreased. The anode outlet is indeed in the condition you described.

This post was last edited by 181128425 on 2009-11-20 at 20:26. It is preliminarily judged that a small amount of the anode coating has peeled off, and the impurities on the ion membrane and the cell tanks have been dissolved. The impact isn’t very significant at the moment; it is estimated that one to two years will be needed, or several more incidents like this will have to occur before the effects become more noticeable. The solution for the hose is to remove the anode hose, wash it, or swap it with the cathode hose. The electrolyzer itself: shut down and clean the cell (make sure to clean it several times). By doing this, it prevents the impurities that are generated from accumulating in the cell channels and on the ion exchange membrane, thus avoiding any negative effects. One is to remove impurities from the hoses so as to facilitate better observation during subsequent production. For the rest, I’ll listen to the expert opinions