Electrochemical and Computational Studies of Some Triazepine Carboxylate Compounds as Acid Corrosion Inhibitors for Mild Steel

• Published in: Journal of bio- and tribo-corrosion Vol. 4; no. 3; pp. 1 - 18
• Main Authors: Alaoui, K., Touir, R., Galai, M., Serrar, H., Ouakki, M., Kaya, S., Tüzün, B., Boukhris, S., Ebn Touhami, M., El Kacimi, Y.
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.09.2018; Springer Nature B.V
• Subjects: Biomaterials; Chemistry and Materials Science; Computer applications; Corrosion; Corrosion and Coatings; Corrosion inhibitors; Corrosion prevention; Corrosion products; Hydrochloric acid; Investigations; Low carbon steels; Materials Science; Parameters; Scanning electron microscopy; Solid Mechanics; Steel; Surface roughness; Tribology; Triazepines carboxylate derivatives; Electrochemical measurements; Mild steel corrosion inhibition; Quantum chemical simulation
• ISSN: 2198-4220; 2198-4239
• DOI: 10.1007/s40735-018-0154-z

The adsorption and corrosion inhibition properties of three triazepines carboxylate substituted compounds, namely, ethyl 4,9-bis(4-chlorophenyl)-8-cyano-3-hydroxy-2,7-dioxo-1,2,5,7-tetrahydropyrido[1,2-b]triazepine-10-carboxylate (2Cl–Et), methyl 4,9-bis(4-chlorophenyl)-8-cyano-3-hydroxy-2,7-dioxo-1,2,5,7-tetrahydropyrido[1,2-b]triazepine-10-carboxylate (2Cl–Me), and ethyl 9-(4-chlorophenyl)-8-cyano-3-hydroxy-2,7-dioxo-4-(p-tolyl)-1,2,5,7-tetrahydropyrido[1,2-b]triazepine-10-carboxylate (Cl–Me–Et) on mild steel corrosion in 1.0 M of hydrochloride acid were investigated by using weight loss, electrochemical, and theoretical investigations. It is found that these compounds act as excellent inhibitors and their inhibition efficiencies follow the order: 2Cl–Me > 2Cl–Et > Cl–Me–Et, and they depend on the type of the substituent. In addition, the possible relations between the experimental and theoretical parameters were discussed. It is found that the theoretical parameters confirmed those obtained by experimental studies. Surface roughness morphology for mild steel before and after hydrochloric acid attack is investigated and discussed using 3D-profilometry images. The scanning electron microscope (SEM) images of the corrosion product confirmed the protection offered by triazepines carboxylate derivatives on the surface of the metal immersed in both media.