Anti-Corrosion Mechanism of Parsley Extract and Synergistic Iodide as Novel Corrosion Inhibitors for Carbon Steel-Q235 in Acidic Medium by Electrochemical, XPS and DFT Methods

Abstract

The parsley extract (PLE) was prepared using absolute ethyl alcohol. The PLE and synergistic iodide were firstly utilized as efficacious corrosion inhibitors to slow down the corrosion rate of carbon steel-Q235 in 0.5 mol/L H2SO4 solution. The anti-corrosion performance was researched by weight loss method, electrochemical tests, surface analysis and quantum chemistry calculation. Results of electrochemical and weight loss tests show that the synergetic PLE and I− exhibit the optimal corrosion inhibition efficiency 99%. The combined inhibitor displays the favorable long-term corrosion inhibition effect, and the inhibition efficiency can maintain more than 90% after 144 h immersion. The introduction of I− makes carbon steel surface with higher negative charge amount, which could be beneficial to the interaction between corrosion inhibitor and Fe atoms. The adsorption behavior obeys the Langmuir isotherm adsorption, and involves chemical and physical adsorption. On the basis of electrochemical consequences and theoretical calculation, the adsorption process and anti-corrosion mechanisms are further explored.

Inhibition of corrosion on API 5L X52 pipeline steel in acid media by Tradescantia spathacea

“…The adsorption process of the corrosion inhibitor is present when it replaces the water molecules and can be adsorbed on the metal surface ( Wan et al, 2021 ; Alao et al, 2022 ). To further develop the adsorption mechanism, Figure 3 displays different adsorption models to fit the obtained results of the weight loss tests used.…”

Synergetic Effect of Potassium Iodide and Miana (Coleus scutellaroides (L.) Benth.) Leaves Extract on Mild Steel in HCl Medium

“…Chemical absorption takes place at this point as a result of the formation of a chemical link between the inhibitor and the surface of the mild steel, creating a coordinating covalent bond. (Indah & Safnowandi, 2020;Untari et al, 2020;Wan et al, 2021).…”

“…According to the research findings, the adsorption of MLE molecules and potassium iodide on the mild steel surface is exothermic, or releases heat, as indicated by the negative value of ΔHads. There is more disorder in the solution when ΔSads is positive (Untari et al, 2020;Wan et al, 2021).…”

Plant wastes as alternative sources of sustainable and green corrosion inhibitors in different environments

“…It is interesting to remark that the likelihood of a given metal to serve as an anode (with respect to other metals) decreases as the value of the electrode potential decreases such that the noble metals (with very low electrode potential) are less susceptible to corrosion compared to metals like Zn and Fe, which can easily form ions in aggressive solutions. Consequently, corrosion is an electrochemical process that requires the setting up of an electrochemical cell (called corrosion cell) before it can proceed [9][10][11][12].…”