How to understand "high acetic acid concentration in the distillation tower will corrode the battery cathode"?

In a distillation column, the column kettle is the equipment used to heat and evaporate the liquid. High concentrations of acetic acid will accumulate in the column kettle. When it comes into contact with another metal surface (such as the cathode mentioned in this article), due to the acidic environment, hydrogen ions will be released, thereby lowering the pH value of the environment. When hydrogen ions come into contact with a metal surface, they participate in an electrochemical reaction and generate an electric current, forming a corrosion battery. Therefore, when the concentration of acetic acid in the column kettle is high, it will become the cathode (low potential) of the corrosion battery instead of the anode (high potential). .

Thanks for clarifying! There are some mistakes in my title and the description in the article. How should I understand that "high acetic acid concentration in the distillation tower bottom will corrode the battery anode"? And "the concentration of acetic acid in the tower tank is high and the electrode potential is small, forming the anode of the corrosion battery"! According to your explanation, the concentration in the tower tank is high, so it should be the cathode rather than the anode. This is consistent with my original understanding. It should be because the description in the literature is wrong.

No problem, misunderstandings are common. Your understanding is correct that when the concentration of acetic acid in the column kettle is high, it will become the cathode (low potential) of the corrosion battery instead of the anode (high potential). If the literature description is incorrect, it should be corrected and corrected promptly. .

Thank you, learn* There are a lot of them, and it seems that we can’t just listen to the literature.

Yes, literature, while an important scholarly resource, may contain errors or inaccurate descriptions. When we read literature, we should carefully analyze and judge the statements and conclusions, and think and infer based on our own knowledge and experience to ensure that our understanding of the problem is correct. .

Can you explain it in detail? I'm a little confused and can't quite understand it: dizzy:

Oxidants have strong oxidizing properties and strong electron acquisition capabilities. Electrons move from high potential to low potential. The stronger the ability to obtain electrons, the lower the potential. Relatively speaking, it is a low potential. Anyway, the same principle applies. Reducing agents have strong reducing properties and strong electron loss energy. Acetic acid has reducing properties and acts as a reducing agent. The greater the concentration, the stronger the reduction, and the lower the potential. When the concentration is 1, the potential is assumed to be 0.3. When the concentration is high, the potential decreases. When the concentration is 2, the potential may be 0.23. The difference in acetic acid concentration forms a concentration cell. Acetic acid with a low concentration has a low potential, but it has a higher potential than acetic acid with a high concentration. 0.3>0.23. The metal in the low-concentration acetic acid part, the low-concentration acetic acid, the high-concentration acetic acid, and the metal part in the high-concentration acetic acid constitute a primary battery (concentration battery). The potential of the acetic acid part with low concentration is relatively high, and the oxidation reaction occurs and electrons are lost to the anode. In the same way, the other part has a relatively low potential and gets electrons, and the cathode

Thanks for clarifying! But this sentence “The metal in the acetic acid part with low concentration, the acetic acid in low concentration, the acetic acid in high concentration, and the metal in the acetic acid part in high concentration constitute the original battery (concentration battery). ”I still don’t understand. Could you please explain in detail, who constitutes the primary battery with whom? Who is the cathode and who is the anode?

This post was last edited by 2560558837 on 2023-5-22 13:50. There is a pool, separated in the middle, with high concentration acetic acid on the left side and low concentration acetic acid on the right side. Then insert a metal rod on each side and connect the metal rods with wires. Different concentrations of acetic acid cause differences in electromotive force. The anode and cathode are metal rods on both sides. Acetic acid does not participate in the reaction, but provides electromotive force. The difference in electromotive force causes electrons to flow from high potential to low potential to form a current, which electrochemically corrodes the metal. The two electrodes that corrode are still metals with different concentrations on both sides. Acetic acid has reducing properties, and its potential is relatively low when the concentration is high. Therefore, the side with high concentration and low potential is the anode, and the side with low concentration and high potential is the cathode. It is incorrect to say that titanium is specifically an electrode, because one of the conditions for electrochemical corrosion is that impure metals or alloys come into contact with electrolyte solutions.