Corrosion Control of Carbon Steel in 1.0 M HCl Using 2-(1H-benzimidazol-2-ylmethyl)-1H-benzimidazole: Weight Loss, Adsorption, SEM, and DFT Study

Authors

• Mohanad Muzahem Khalaf, School of Materials and Mineral Resources Engineering, Engineering Campus, Universiti Sains Malaysia, 14300 Nibong Tebal, Penang, MalaysiaFollow
• F. F. Sayyid, College of Production Engineering and Metallurgy, University of technology, Baghdad, 10001, IraqFollow
• Ayad Abbood Abdulhasan, Department of Mechanical Engineering, Universiti Tenaga Nasional, Selangor, MalaysiaFollow

Abstract

The corrosion inhibition performance of 2-(1H-benzimidazol-2-ylmethyl)-1H-benzimidazole for carbon steel in 1.0 M HCl was investigated using weight loss measurements, adsorption isotherm analysis, scanning electron microscopy (SEM), and density functional theory (DFT) calculations. The weight loss results showed that inhibition efficiency increased with inhibitor concentration and reached 95.5% at 1000 ppm. Adsorption of the inhibitor molecules on the carbon steel surface followed the Langmuir adsorption isotherm, indicating the formation of an adsorbed protective layer. SEM micrographs showed that the inhibited metal surface was smoother and less damaged than the uninhibited surface. DFT calculations, including HOMO and LUMO analysis, provided molecular-level insight into the adsorption behavior of the inhibitor. The combined experimental and theoretical results indicate that 2-(1H-benzimidazol-2-ylmethyl)-1H-benzimidazole is an effective inhibitor for carbon steel in acidic medium.

Recommended Citation

Khalaf, Mohanad Muzahem; Sayyid, F. F.; and Abdulhasan, Ayad Abbood (2026) "Corrosion Control of Carbon Steel in 1.0 M HCl Using 2-(1H-benzimidazol-2-ylmethyl)-1H-benzimidazole: Weight Loss, Adsorption, SEM, and DFT Study," AUIQ Conference Proceedings: Vol. 2: Iss. 1, Article 7.
DOI: https://doi.org/10.70176/3107-2682.1015
Available at: https://acp.alayen.edu.iq/journal/vol2/iss1/7