Corrosion Inhibition of Mild Steel in Hydrochloric Acid Medium Using a Plant Extract as a Green Inhibitor

Abstract

Mild steel is widely used in industry but corrodes readily in acidicenvironments such as those encountered during acid cleaning and pickling,and inhibitors are added to reduce this attack. Plant extracts have attractedattention as green inhibitors that are inexpensive, non-toxic, andenvironmentally acceptable, in contrast to many conventional inhibitors. This paper reports the corrosion inhibition of mild steel in hydrochloric acidmedium using a plant extract as a green inhibitor. The inhibition was studiedby weight-loss and electrochemical methods at several inhibitor concentrations and temperatures, and the adsorption of the inhibitor on thesteel surface was analysed. The results show that the plant extract acted as an effective inhibitor, the inhibition efficiency increasing with inhibitorconcentration and decreasing with temperature, reaching a high value at thehighest concentration tested. The electrochemical measurements confirmedthe reduction in corrosion rate, and the adsorption of the inhibitor followedthe Langmuir isotherm. The study demonstrates that the plant extract is aneffective green corrosion inhibitor for mild steel in acidic medium anddiscusses the inhibition mechanism.  KEYWORDS: Corrosion Inhibition, Mild Steel, Green Inhibitor, Plant Extract, Hydrochloric Acid, Inhibition Efficiency, Adsorption.