The Effect of new reduced form of Schiff-base Ligands on corrosion inhibition of API 5L in seawater

Abstract Three synthesized Schiff base named 2,2’- (((2,2-dimethylpropane-1,3-diyl)bis(azanediyl)bis(methylene)disphenol (I1), 4,4’- (((2,2-dimethylpropane-1,3-diyl)bis(azanediyl)bis(methylene)bis(2-methoxyphenol) (I2) and 6,6’- (((2,2-dimethylpropane-1,3-diyl)bis(azanediyl)bis(methylene)bis(2-methoxyphenol) (I3) were evaluated as corrosion inhibitors for API 5L grade B steel in the artificial seawater by electrochemical impedance, polarization and Quantum chemical calculations methods. The results showed that all three compounds act as good inhibitors for carbon steel, but the I3 has the best inhibition efficiency of about 58% at 1mg/L. The results of density functional theory method were consistent with the experimental results.