Inhibition of the Corrosion of Carbon Steels by Trehalose Lipid Surfactants

By using corrosion-electrochemical and quantum-chemical methods, we investigate the inhibition of the process of corrosion of carbon steel by trehalose lipid surfactants. It is shown that this substance efficiently inhibits the corrosion processes in steel in a medium of artificial acid rain. Upon attainment of the critical concentration of micelle formation equal to ≈ 0.3 g/liter, the subsequent increase in the micelle content in the corrosive medium does not lead to a noticeable increase in the protective anticorrosion effect. The mechanism of corrosion inhibition is realized by the adsorption of trehalose lipid surfactant (TLS) molecules on the surface of steel by hydrophilic carbonyl and hydroxyl groups according to the donor–acceptor mechanism accompanied by the formation of a barrier film. An additional introduction of small amounts of poorly soluble zinc phosphate in the medium inhibited by the TLS noticeably weakens the corrosion of carbon steel. The degree of its protection becomes as high as 93–96%. This composition guarantees a higher degree of protection of carbon steel in the medium of artificial acid rain than its separate components.