Etude de l'inhibition de la corrosion de l'acier en milieu acide par l’extrait des feuilles de figuier.

Abstract

In this study, an aqueous extract of fig leaves (EFF) prepared by a simple and economical method is tested as a green inhibitor against corrosion of steel in acid medium. Anti-corrosive activity was evaluated using the mass loss method, polarization curves and electrochemical impedance spectroscopy. The powder of fig leaves was characterized by FTIR. This analysis showed that this powder is a very rich of bioactive compounds. To understand the adsorption mechanism, a thermodynamic study was carried out and different isotherms were studied. The results obtained confirm that this inhibitor can inhibit steel and its inhibitory efficiency can reach 72% and increases with temperature rise. EFF acts as mixed type inhibitor, adsorbs to the metal surface by chemisorption and obeys the Langmuir model. This inhibitor provides a good barrier against infiltration of the corrosive medium on the metal surface.