Substitution Effect of two Oxygen Atoms by Sulphur Atoms in New Synthesized Benzodiazepine Molecules towards Mild Steel Corrosion Inhibition in Hydrochloric Acid

摘要

The corrosion inhibition of mild steel in molar HCl by two newly synthesized benzodiazepinederivatives, namely: 10-benzyl-pyrrolo[2,1-c][1,4]benzodiazepine-5,11-dione (BZD=2O), and 10- benzyl-pyrrolo[2,1c][1,4]benzodiazepine-5,11-dithione (BZD=2S); has been investigated at 308 Kusing electrochemical and weight loss measurements. The results showed that these compounds weregood inhibitors and the inhibiting efficiency increased with rise concentration of the studied inhibitors.Compound BZD=2S showed better protection properties even at higher temperatures. BZD=2S wasadsorbed on the mild steel surface according to a Langmuir isotherm adsorption model. The associatedkinetic and thermodynamic parameters for both metal dissolution and inhibition processes have beendetermined and discussed.