ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

The inhibition performance of sulfaguanidine as corrosion inhibitor of iron: an insight from mathematical, statistical, and density functional theory studies

Nabaa B. Ali, Adiba A. Mahmmod, Anees A. Khadom, Mustafa M. Kadhim, and Ahmed A. Al-Amiery

Department of Chemical Engineering, College of Engineering, University of Diyala, Baquba City, Iraq

E-mail: aneesdr@gmail.com

Received: 6 May 2025  Accepted: 22 August 2025

Abstract:

In the present work, the inhibition performance of sulfaguanidine (SG) as a corrosion inhibitor of iron was investigated mathematically via regression and statistical analysis and theoretically via quantum chemical calculations. Four models were proposed, including a linear model (LM), a linear model with interaction (LIM), a quadratic model with interaction (QIM), and a kinetics model (KM). Among the mathematical models, the QIM was the most accurate one, with a 0.9943 correlation coefficient. The kinetics model demonstrated a correlation coefficient of 0.9954. These models showed that the effect of temperature on the corrosion was more significant than the effect of inhibitor concentration. On the other hand, quantum chemical calculations indicate that the difference between HOMO–LUMO (ΔE) was 0.199 eV, which indicates a high reactivity of SG. The strong adsorption is due to a donor–acceptor bonding connection between the Fe surface and the SG molecules, which has been studied in more detail.

Keywords: Organic corrosion inhibitor; Regression; Statistical analysis; Density functional theory; Electronic structure; Adsorption behavior

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-025-04346-4

Chemical Papers 79 (12) 8733–8751 (2025)