• Where is Cleansol’s area of service?

Cleansol offers services to the South-Atlantic region, including:

– North Carolina
– South Carolina
– Georgia
– Virginia
– West Virginia
– Florida

• Are passivation services offered on-site or at Cleansol’s facilities?

We offer both options: Smaller parts and tube assemblies can be passivated in our facilities. Hygienic piping systems and larger pieces of equipment such as tanks or reactors will require mobilization to the client site.

• What is passivation?

Passivation is a chemical process designed to increase the corrosion resistance of stainless steel surfaces. Passivation effectively removes free iron and other foreign materials from the surface of the treated stainless steel.

• How long does the passive layer last after a passivation procedure?

Passivation will remove free iron in the surface of the stainless steel, creating a rich chromium oxide layer in the treated surface. There is no determined time frame for the passive layer to be active. It all depends on the existing conditions and parameters for each system, like temperature, medium or product handled in the system, sanitization cycles, etc.

• Is cleaning needed before passivation activities?

Cleaning is highly recommended prior to passivation because it will remove any contaminants from the surface of the stainless steel, providing full contact for the passivation solution.

• Is there a method to verify passivation?

Yes, there are several approved methods to test passivation, including Copper-Sulfate and Ferroxyl tests. Also, there are electronic devices in the market designed for passivity testing.

Cleansol has several methods available, but we prefer to use the Koslow Passi-Flash 3036 stainless steel passivation test kit which provides recordable data.

• Does Cleansol uses citric or nitric acid for passivation?

We can use either citric or nitric acid for passivation, however, our proprietary procedures are based on citric acid, as we consider it to be a safe and environmentally friendly alternative.

• What is the best product for passivation?

For a long time, nitric acid was used for passivation. As the market changed, several studies revealed citric acid as a good alternative for passivation, offering the advantage of being more user friendly and easier to dispose.

Right now, there are different passivation products in the market with proprietary recipes, most of them having citric acid as the main component.