Investigation on Two Salen Type Schiff base Compounds as Corrosion Inhibition of Copper in 0.5 M H2SO4

The inhibition of copper corrosion by two new Schiff bases under 0.5 M H2SO4 at 250C was studied by electrochemical tests (potentiodynamic polarization and AC impedance technique). These studies have shown that two Schiff bases are good inhibitors for copper in 0.5 M H2SO4. Results obtained reveal that, as the concentration of two Schiff bases increases, the polarization resistance values (Rt) increases, the double layer capacitance values (Cdl) decrease and inhibition efficiency increases. The inhibition process was attributed to the formation of an adsorbed film on the metal surface that protects the metal against corrosive agents. It was found that these two Schiff bases were chemically adsorbed on the copper surface and follow Langmuir isotherm. The Tafel polarization have shown that two Schiff bases act as anodic inhibitors.