Comprehensive Analysis of the Effect of New Efficient and High Temperature Resistant Imidazoline Derivatives on the Corrosion Inhibition Performance of Q235: Experimental and Theoretical Studies

Abstract

Background: Imidazoline derivatives were widely used in the field of metal corrosion protection due to the low toxicity and excellent corrosion inhibition performance. In order to further reduce synthesis costs and improve corrosion inhibition performance, oleic acid, diethylenetriamine, and anisaldehyde were used as raw materials to synthesize imidazole Schiff corrosion inhibitors (HM), and the corrosion inhibition mechanism on Q235 in 1.0 mol/L HCl solution was studied rigorously. Method: The corrosion inhibition ability was verified using weight loss and electrochemical experiments. Scanning electron microscope (SEM), energy dispersive spectrometer (EDS), and X‐ray photoelectron spectroscopy (XPS) were used to detect and analyze the protective film formed on the surface of Q235 after weight loss. Density functional theory (DFT) demonstrated the adsorption sites and reaction activity of the corrosion inhibitor, Molecular Dynamics (MD) further validated the corrosion inhibition mechanism. Significant Findings: Imidazoline corrosion inhibitor could form a stable protective film on the surface of Q235. With the concentration increased of HM, the corrosion inhibition efficiency increased gradually, and with the temperature increased, the corrosion inhibition efficiency decreased gradually. At the optimal concentration, the corrosion inhibition rate could reach 98.98%. HM belonged to a mixed type corrosion inhibitor that mainly suppresses the cathode and could spontaneously adsorb on the metal surface, following the Langmuir isotherm for adsorption.