Evaluation of 1-Hexadecylbenzimidazole as a Corrosion Inhibitor on Low Carbon Steel 15 % HCl Solution Interface

The performance of 1-Hexadecylbenzimidazole (HDBI) as an effective corrosion inhibitor of low carbon steel (LCS) in 15 % HCl solution was evaluated with different electrochemical techniques and weight loss measurements. HDBI was a mixed-type corrosion inhibitor with 50 mg L⁻¹ concentration achieving a 97 % corrosion inhibition efficiency in 15 % HCl solution at 25 °C. The nature of adsorption of HDBI on LCS in the corrosive medium was predicted to be chemisorption, as revealed by the Langmuir isotherm model and the thermodynamic study. Weight loss measurements of 50 mg L⁻¹ HDBI at a different temperature indicated the effectiveness of HDBI at elevated temperatures. The X-ray photoelectron spectroscopy (XPS) was used to ascertain the chemical state of the adsorbed HDBI on the LCS surface. The surface morphology analysis was investigated with a flame emission scanning electron microscope integrated with an energy dispersive spectrometer (FESEM-EDX).