Corrosion inhibitors (IC) is called chemical compounds which, when present in the corrosion system in sufficient concentration reduces the corrosion
rate without significantly altering the concentration of any corrosive reagent.
Corrosion inhibitors may be chemical compounds and compositions. The content of the corrosion inhibitor in the medium should be small.
The action of the corrosion inhibitors due to a change of the surface state of the metal due to adsorption inhibitor or the formation of sparingly soluble metal cation compounds. Protective layers created corrosion inhibitors always applied thinner coatings. Corrosion inhibitors may act in two ways: reduce the active surface area, or change the activation energy of the corrosion process.
Protection against corrosion by corrosion inhibitors has been widely used in many branches of modern industry and agriculture: the transportation of gas and oil by pipelines, to save metal in between the operating period to protect against corrosion of fuel and lubricants, as well as water- salt, acid, alkaline, aqueous-organic or organic media in fresh and sea water when corrosion in atmospheric conditions and soil.