Justicia adhatoda (Vasaka) Leaf Extracts as Eco-friendly Corrosion Inhibitor for Mild Steel in Potable Water

The corrosion inhibition efficiency of the vasaka leaf extract for protecting mild steel in potable water (neutral aqueous medium) was studied by weight loss, Open circuit potential monitoring and potentiometric polarization methods. The inhibition test was performed in potable water rather than deionized water because inhibitors are normally applied in neutral and industrial waters. The extract of vasaka leaf has been found to show significant corrosion inhibition of mild steel in neutral aqueous environment. The inhibition efficiency increases with increasing the concentration of leaf extract and decreases with temperature. The inhibition efficiency calculated based on weight loss method was found to be above 95% when the electrolyte contain 700 ppm of the inhibitor. The results of different techniques used to measure the inhibition efficiency of the leaf extract are well co-related with each other.