Dealing with excess or expired plating additives is a crucial aspect of maintaining electroplating solutions. Over time, these additives accumulate and form organic impurities in the plating tank, which can adversely impact the quality of the plating. It is essential to regularly treat these organic impurities to ensure the proper functioning of the plating solution.

When the coating appears bright but lacks good dispersing ability, leading to peeling and cracking, it is often a result of the presence of organic impurities. It is challenging to completely remove these impurities if the proper method is not employed. The key treatment process involves first treating the plating solution with hydrogen peroxide, followed by heating and the addition of an appropriate amount of activated carbon. In cases of high levels of organic impurities, potassium permanganate is used for treatment. This involves adjusting the pH to 3, heating to 60-80 °C, and adding a specified amount of pre-dissolved potassium permanganate for thorough removal, followed by filtration and pH adjustment.

For organic pollutants that cannot be removed by the above method, such as those from animal glue or wax prototypes, tannic acid is added to the plating solution. This results in the formation of flocs, which can be removed after sufficient precipitation. Combining this treatment with activated carbon treatment can effectively eliminate all organic impurities, ensuring the quality of the plating solution.