SYNERGISTIC CORROSION INHIBITION EFFECT OF MILD STEEL IN SEA WATER BY 2-AMINO PYRIDINE - Zn2+ SYSTEM

Abstract

The corrosion inhibition efficiency of 2-Amino Pyridine (2AP) in controlling the corrosion of Mild steel immersed in Sea water for three days in the presence and absence of Zn2+ has been studied by weight loss method. The formulation consisting of 250 ppm of 2AP and 50 ppm Zn2+ offers 97% inhibition efficiency. The synergistic effect exists between 2AP and Zn2+ system. The influence of sodium lauryl sulphate (SLS)between 2AP and Zn2+ system control the microbial corrosion.Polarization study shows that the best formulation system controls anodic reaction predominantly. The AC impedance spectral studies reveal that the protective film formed on the metallic surface.The FTIR spectra study leads to the conclusion that the Fe2+ -2AP complex formed on anodic sites of the metal surface controlling the anodic reaction and Zn(OH)2 formed on the cathodic sites of the metal surface controlling the cathodic reaction. The mechanism of corrosion inhibition is proposed based on the results obtained from weight loss study and polarization study. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were used to investigate the nature of protective film formed on the Mild steel surface and for explaining the mechanistic aspects of the inhibition process