Experimental and Computational Exploration of Chitin, Pectin, and Amylopectin Polymers as Efficient Eco-Friendly Corrosion Inhibitors for Mild Steel in an Acidic Environment: Kinetic, Thermodynamic, and Mechanistic Aspects

Ahmed Fawzy; Arafat Toghan; Nada Alqarni; Moataz Morad; Magdi E A Zaki; Moustafa M S Sanad; Abbas I Alakhras; Ahmed A Farag

doi:10.3390/polym15040891

Experimental and Computational Exploration of Chitin, Pectin, and Amylopectin Polymers as Efficient Eco-Friendly Corrosion Inhibitors for Mild Steel in an Acidic Environment: Kinetic, Thermodynamic, and Mechanistic Aspects

Polymers (Basel). 2023 Feb 10;15(4):891. doi: 10.3390/polym15040891.

Authors

Ahmed Fawzy^{1

2}, Arafat Toghan^{3

4}, Nada Alqarni⁵, Moataz Morad¹, Magdi E A Zaki³, Moustafa M S Sanad⁶, Abbas I Alakhras³, Ahmed A Farag⁷

Affiliations

¹ Chemistry Department, Faculty of Applied Sciences, Umm Al-Qura University, Makkah 21955, Saudi Arabia.
² Chemistry Department, Faculty of Science, Assiut University, Assiut 71516, Egypt.
³ Chemistry Department, College of Science, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh 11623, Saudi Arabia.
⁴ Chemistry Department, Faculty of Science, South Valley University, Qena 83523, Egypt.
⁵ Department of Chemistry, College of Science and Arts in Balgarn, University of Bisha, Bisha 61922, Saudi Arabia.
⁶ Central Metallurgical Research & Development Institute, P.O. Box 87, Helwan, Cairo 11421, Egypt.
⁷ Egyptian Petroleum Research Institute (EPRI), Cairo 11727, Egypt.

Abstract

Herein, the inhibition impacts of chitin, pectin, and amylopectin as carbohydrate polymers on the corrosion of mild steel in 0.5 M HCl were researched utilizing various experimental and theoretical tools. The acquired outcomes showed that the inhibition efficiencies (% IEs) of the tested carbohydrate polymers were increased by raising their concentrations and these biopolymers acting as mixed-kind inhibitors with major anodic ones. The acquired % IEs values were reduced with rising temperature. The higher % IEs of the tested polymers were inferred via powerful adsorption of the polymeric molecules on the steel surface and such adsorption obeyed the Langmuir isotherm. The computed thermodynamic and kinetic quantities confirmed the mechanism of physical adsorption. The kinetics and mechanisms of corrosion and its protection by polymeric compounds were illuminated. The results obtained from all the techniques used confirmed that there was good agreement with each other, and that the % of IEs followed the sequence: chitin > amylopectin > pectin.

Keywords: carbohydrate polymers; corrosion; experimental and theoretical studies; inhibitors; mild steel.

Grants and funding

RP-21-09-76/the Deanship of Scientific Research at Imam Mohammad Ibn Saud Islamic University (IMSIU) for funding and supporting this work through Research Partnership Program