Corrosion Inhibition of Mild Steel in Hydrochloric Acid Solution by an Isatin-aniline Compound

Abstract

Recently the researchers go to the eco-friendly corrosion inhibitors. In the present investigation, isatin which found in many plants, Isatis tinctoria, Calanthe discolor and Couroupita guianensis has been used as corrosion inhibitor. An isatin-aniline compound, namely ethyl 4-amino-N-(3-isatinyl) benzoate (AIB), was successfully synthesized in high yield and its inhibition impact on corrosion of MS (mild steel) in hydrochloric acid as corrosive solution was examined via weight loss and Scanning electron microscope techniques. The results acquired appeared that AIB has employ perfect as a corrosion inhibitor at low concentrations towards mild steel in HCl bath. The impact of temperature on the corrosion behavior of MS in corrosive bath with presence of (250) ppm of AIB has been investigated in the range of temperatures (303-333) K. The thermodynamic parameters for inhibiting process were investigated to find out the mechanism of corrosion inhibition of MS acid bath.