Study on the synergistic corrosion inhibition effect of metal ion modified citrus peel extract on Q235 carbon steel in hydrochloric acid

Abstract

Corrosion inhibitors extracted from plants have good prospects for development, but the lack of outstanding corrosion inhibition efficiency is a serious problem. Therefore, in this paper, the extract of orange peel was used as a green corrosion inhibitor (Org), and in order to obtain excellent corrosion inhibition effect, it was combined with FeCl₃ and TiCl₄ to form two nanocomposite inhibitors, Org/Fe and Org/Ti, respectively. The corrosion inhibition performance and mechanism of the three corrosion inhibitors were investigated on carbon steel in 1.0 mol/L HCl solution. The weight loss and electrochemical results showed that the corrosion inhibition efficiencies of Org/Fe and Org/Ti were higher than that of Org, which indicated that Ti⁴⁺ and Fe³⁺ could effectively improve the corrosion inhibition performance of Org. The adsorption of Org, Org/Fe and Org/Ti on Q235 indicated that the adsorption belonged to Langmuir isothermal adsorption. The results of particle size analysis showed that Org/Fe and Org/Ti belonged to nanocomposite inhibitors. Theoretical calculations indicate that the addition of metal ions forms a dense protective film, thereby more effectively isolating the corrosive medium.