Titanium anodes have a certain service life during electrolysis operations. When the voltage rises to almost no current passes through, the titanium anode becomes inactive, a phenomenon known as anode passivation. The reasons for titanium anode passivation are as follows:

1. Coating peeling: The titanium anode titanium substrate and the coating titanium anode are active internally, and the electrochemical reaction is only the titanium active coating. The coating and matrix are not strong enough, and if they detach from the titanium substrate, to some extent, the titanium anode will lose its function. (Can be divided into crushed peeling, convex belly peeling, and cracked peeling)

2. Coating cracks: During the electrolysis process, a new ecological oxygen titanium anode is generated, and some of the emissions between the interface active coating and electrolyte, and then leave the anode surface to generate oxygen/chlorine to solve the problem; Due to cracks in the active coating and the adsorption of another part of oxygen on the anode surface, the active coating inside the titanium anode diffuses or migrates to the interface between the coating and the titanium substrate. Then, oxygen is chemically adsorbed on the titanium substrate surface to form a non-conductive oxide film (TiO2) with titanium, resulting in reverse resistance. Or the electrolyte may invade through cracks in the coating, causing slow oxidation of the titanium substrate and corrosion of the interface with the active coating, causing the ru iridium titanium active coating to peel off, resulting in an increase in the titanium anode potential. The increase in potential further promotes the dissolution of the coating and the oxidation of the titanium based material.

3. RUO2 dissolution: reduces the occurrence of oxygen and can slow down the formation of oxide films. When the total current density of electrolysis increases, the increase in chlorine production rate is much greater than the increase in oxygen production rate. Therefore, an increase in current density is beneficial for reducing the oxygen content in chlorine. Pre oxidation of the titanium substrate to form an oxide film can increase the bonding force between the active coating and the titanium substrate in the titanium anode, making the coating firm and preventing the active coating from falling off and dissolving.

4. Oxide saturation: The active coating is composed of non stoichiometric RuO2- and TiO2, which belong to oxygen deficient oxides. Non stoichiometric oxides are actually the activation centers of chlorine discharge. The more such oxides there are, the more active centers there are, and the better the activity of the titanium anode. The conductivity of titanium anode is generated by the isomorphic RuO2 and TiO2 after heat treatment. There are some oxygen gaps in the performance of twisted n-type mixed crystals. When these oxygen gaps are filled with oxygen, the overpotential rapidly increases, leading to passivation.