Corrosion inhibition of brass in presence of terdentate ligands in chloride solution

The inhibition of two terdentate ligands, 2-[(E)-pyridin-2-ylimino)methyl)]phenol and 2-[(pyridin-2-ylamino)methyl]phenol, abbreviated L1 and L2 respectively, on the corrosion of brass in 0.10 M NaCl solution under various conditions, has been studied by means of the potentiostatic polarization and AC impedance methods. The studies show that terdentate ligands, L1 and L2 inhibit the corrosion of brass in chloride solution and that the inhibiting efficiency increases with an increase in their concentrations. Self-assembled films of these substances were also prepared on the brass surface. These films improved significantly the protecting ability of brass surface to corrosion in 0.10 M NaCl solution. When the films were modified with benzotriazole (BTA), the quality and corrosion resistance of films improved markedly.