An investigation of modified dialdehyde starch as a highly efficient green corrosion inhibitor for carbon steel in 1 M HCl medium: Synthesis, experimental and theoretical studies

• Published in: Industrial crops and products Vol. 215; p. 118534
• Main Authors: Chen, Mengjin, Chen, Siting, Pi, Jinyu, Chen, Shijian, Wang, Qi, Fu, Chaoyang
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-09-2024
• Subjects: Adsorption model; Electrochemical measurements; Green corrosion inhibitor; Starch derivative; Theoretical calculations; Electrochemical measurements; Adsorption model; Theoretical calculations; Starch derivative; Green corrosion inhibitor
• ISSN: 0926-6690; 1872-633X
• DOI: 10.1016/j.indcrop.2024.118534

Compared to small organic molecule corrosion inhibitors, polymer corrosion inhibitors offer numerous advantages in terms of adsorption coverage on the metal surface and the presence of multiple active sites for adsorption. A dialdehyde starch Schiff base was synthesized by modification of natural polymer starch and tetraethylene pentaamine, and it was characterized by X-ray diffraction, gel chromatography and thermogravimetry. The corrosion inhibition behaviors of dialdehyde starch Schiff base as an oligomer for low carbon steel in 1 M HCl were investigated. Compared to the common starch derivatives, the dialdehyde starch Schiff base has good water solubility and inhibition performance. The inhibition efficiency can reach 93.2% with 0.16 mM in 1 M HCl solution at 333 K. Double aldehyde starch Schiff base is a mixed corrosion inhibitor that mainly inhibits cathodic reactions. Its adsorption on the surface of carbon steel follows the Langmuir adsorption equation, and the nitrogen -containing groups in the molecules are adsorbed on the surface of the steel through physical and chemical reactions. Quantum chemical calculations confirmed the experimental results.
•Dialdehyde starch Schiff base with good water-solubility is synthesized and characterized.•Dialdehyde starch Schiff base as an oligomer exhibits excellent inhibition efficiency of 93.22%.•Dialdehyde starch Schiff base adsorbs onto steel surface through physical/chemical interactions of N-Fe.