Corrosion Inhibition Efficiency of Terminalia Catappa Leaves Extracts on Stainless Steel in Hydrochloric Acid

Abstract

Abstract Corrosion inhibition potential of Terminalia catappa leaves extract was investigated using Grade 304 austenitic stainless steel in 1.0 M HCl solution with a view to finding natural, eco-friendly, low-cost and readily available corrosion inhibitor. The corrosion inhibitory characteristics of the extract were investigated by utilizing gravimetric measurements and microstructural surface changes obtained from scanning electron microscopy (SEM). This study was carried out in the absence and presence of Terminalia catappa inhibitor (0.01-0.09 g/ml) and temperatures (30-50 °C). Data obtained from weight loss experiments and adsorption isotherms (El-Awady, Temkin, and Freundlich) indicated that Terminalia catappa leaf extract repressed the corrosion of stainless steel in acidic media by 96.8 % at 30 °C and conforms to physisorption adsorption mechanism. Inhibition efficiency (% IE) of the extract improved with increasing extract concentration but declined with rising temperature.