The use of Brugmansia arborea as a green corrosion inhibitor for AISI 1018 carbon steel in acid media

Abstract

This study shows the inhibitory activity of the hexane, acetone and methanol extracts of Brugmansia arborea (B. arborea) during the corrosion of 1018 steel in 0.5 M of H2SO4. This was carried out by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization curves (PDP) techniques. The maximum efficiency for the three extracts was registered with 400 and 500 ppm concentrations, obtaining 98% by EIS and 80% by PDP. Through PDP, an inhibition behavior of the cathodic type was determined. During the residence time test, B. arborea reached a maximum inhibition efficiency of 98% at 24 h with acetone extract and at 20 h with methanol extract. The compound's chemical structure present in B. arborea was analyzed by the Fourier Transform infrared spectroscopy technique, and the presence of functional groups such as the amines was observed. The reason why an inhibitory activity is attributed to these compounds is because they contain nitrogen that may easily form complexes that are strongly adsorbed creating a thin layer on the metallic surface.