Study of Corrosion of Zinc in Nitric acid and Its Inhibition

Present study was carried out to evaluate loss on corrosion of zinc metal in various concentration of nitric acid and responsible for the protection of zinc metal used aromatic amines (Toludines, Nitroanilines, Chloroanilines) and aliphatic amines (ethanolamine, ethylamine). The corrosion of copper loss increases with increase in all acid concentration. The corrosion loss is affected by the presence of diffusion oxygen, nature of complex reaction taking place and also the nature of protective film. Inhibition efficiency was increased in all studied at all inhibitor of aromatic amino acid inhibitors with the increase. In all types of aromatic amino o-chloro aniline, m nitroaniline are proved an excellent inhibitor. Aliphatic amines ethanolamine in all it proved an excellent inhibitor of acid in all. Thermodynamics parameters like energy of activation (Ea), free energy of adsorption (¿G °), heat of adsorption (Qads), enthalpy (¿H) and Entropy (¿S) are also studied. Tafel slope in presence of inhibitors anodic and cathodic process indicate their effect on both the corrosion of zinc in nitric acid.