Method for removing rouging from stainless steel

A method for removing rouge formation on stainless steel, the method comprising the steps of separately contacting a stainless steel substrate having rouging with each of the following solutions:

• an alkaline oxidizing solution comprising permanganate and/or bromate compound, or any of the corresponding salts as an oxidizing agent;
• a neutral or alkaline reducing solution comprising dithionite, sulphite, bisulphite, disulfite, any of the corresponding salts and/or a combination thereof as a reducing agent;
• and,
• an acidic reducing solution comprising at least 5.0×10−3 to at most 1.0×10−1 mol/l of complexing anions and at least 1.35×10−5 to at most 9.0×10−5 mol/l of Fe2+;
• wherein the method comprises contacting the stainless steel substrate with the solutions in the following order:
• first with said alkaline oxidizing solution, second with said neutral or alkaline reducing solution, and third with said acidic reducing solution, or
• first with said alkaline oxidizing solution, second with said acidic reducing solution, and third with said neutral or alkaline reducing solution,
• thereby removing rouging from said stainless steel substrate.