CitriSurf Citric Acid Passivation
The CitriSurf® citric acid cleaning and passivation process is based on cutting edge technology using safe and environmentally friendly citric acid to remove the free iron from the surface of stainless steel.
Stainless steel is comprised of a mixture of metals, primarily iron, chromium, nickel and in some cases molybdenum and manganese along with other materials in small quantities. It is this unique blend that allows the special property of corrosion resistance by forming an outer protective passive oxide layer. Stainless steel surfaces can be made highly resistant to corrosion if they are properly cleaned and passivated prior to use. Even with 300 series austenitic stainless steel, once a corrosion site has started, it will only get worse, being continuous and self-catalyzing. In corrosive environments the growth of the corrosion site will accelerate rapidly! Thus, proper cleaning and passivation of surfaces prior to use is essential to achieve maximum resistance to corrosion.
Corrosion prevention with Citric passivation using CitriSurf technology has proven to be a vast improvement over the traditional nitric acid formulations. After stripping the iron from the surface, the citric acid forms a water-soluble complex with the iron ions, tying them up so that they are no longer able to have a negative impact. The CitriSurf bath will not allow the iron to precipitate again like nitric acid is known to do. In addition, citric acid does not pose the health and environmental hazards that are present with nitric acid. By their very nature, CitriSurf products are non toxic, non-corrosive and biodegradable. Citric acid is the natural organic acid found in oranges and other citrus fruits. It is Generally Regarded As Safe (GRAS) and is commonly used in many foods and beverages. This means that CitriSurf is compatible with the environment and can usually be disposed into sanitary sewage systems with minimal waste treatment to meet environmental agency approvals.