Mild Steel corrosion Inhibition using Bredelia ferruginea Extract in Acidic Medium Adetukasi Adekunle*, Olasunkanmi Ajayi Babatunde, Elvis Okoronkwo Afamefuna Ekiti State College of Health Science and Technology Ijero-Ekiti, Federal University of Technology Akure, Federal University of Technology, Akure *Corresponding Author E-mail: adekunle.adetukasi@gmail.com
Online published on 19 December, 2019. Abstract The mild steel corrosion using Bredelia ferruginea extract in acidic medium was carried out using gravimetric method of corrosion studies, scanning electron microscopy was used to carry out surface morphology of mild steel, Fourier transform infrared spectroscopy was used to determine the phytochemistry of plant extracts and to investigate the adsorption mechanism of inhibitor molecule deposited on the metal surface. It was found that both the Stem bark and leaf of Bf extracts retarded the corrosion of mild steel in 1.0 M HCl solution. The inhibition efficiency increased with increase in extract concentration but decreased with decrease in concentration of plant extract. It was also observed that the inhibition efficiency of the bark which is 96.15% is higher than the leaf of 94.58%. The values of activation energy (Ea) obtained is suggestive of physical adsorption mechanism while the values of Gibbs free energy (ΔG0) obtained indicated a spontaneous adsorption of the extract components on the metal surface. The data obtained from kinetic treatment followed a pseudo first order reaction. The adsorption of Bf extract onto the mild steel surface followed Temkin, Lanqmuir and Freundlich adsorption isotherm models. The result obtained from indicated the presence of a good protective film upon adsorption of inhibitor molecules onto the mild steel surface, which was responsible for inhibition of corrosion. Investigation of phytochemical constituents showed that the extracts contained alkaloids, flavonoids, saponins, tannins, glycoside and saponins glycosides. The stem bark and leaf of plant investigated showed a good potential for green corrosion inhibitors. Top Keywords Corrosion, Bredelia ferruginea, Inhibition, Mild Steel, phytochemical constituents, gravimetric method. Top |