Acid corrosion inhibitors are chemicals that are added to acidic environments to reduce the rate of metal corrosion. Their main functions include:
- Surface Protection: They form a protective film or barrier on the metal surface, preventing direct contact between the acid and the metal.
- Passivation: They facilitate the formation of a passive oxide layer on the metal surface, which is more resistant to acidic attack.
- Adsorption: They adsorb onto the metal surface, either physically or chemically, reducing the active sites available for corrosive reactions.
- Complex Formation: They react with metal ions to form stable complexes, reducing the rate of metal dissolution.
- Reduction of Hydrogen Evolution: They decrease the rate of hydrogen evolution, which is often a byproduct of metal corrosion in acidic environments.
Overall, acid corrosion inhibitors are used to prolong the life of metal structures, reduce maintenance costs, and prevent failure in various industrial applications such as pipelines, boilers, and acid cleaning processes.