Acid Potassium Chloride Zinc Electroplating Brightener

There are two kinds of iron impurities in the bath: one is iron bivalent, the other is iron trivalent. The plating solution can still produce normally when the content of ferric iron reaches 10g/L, which may be related to the fact that ferric iron cannot produce electrochemical co-deposition with zinc on the cathode. The bivalent iron in the bath is more sensitive, so that the range of current density is significantly reduced, especially affecting the quality of the coating at the high current density. In the hull cell experiment, it was found that at 0.2g/L iron, nearly 20mm of the high current end appeared scorched and rough area, and at 0.3g/L, almost half of the sample appeared scorched and rough area, while the coating in the low current area was gray. This plating solution for rolling plating, will appear close to the wall of the rolling plating coating serious scorch, this is the common black spot potassium chloride rolling plating, that is, the barrel eye mark. Generally in production, when the iron content is greater than 5g/L, the coating in the low current density area will appear yellow. The treatment method of this fault is to add 30% hydrogen peroxide in the plating solution, the ratio is 0.5-1ml/L per liter of the plating solution, and then stir fully, adjust the PH value of the plating solution to 6, and then filter the plating solution to remove the iron in the plating solution.