1,10,-Phenanthroline as Corrosion Inhibitor for Mild Steel in Sulfuric Acid Solution

1,10,-Phenanthroline (Phen) has been examined as a corrosion inhibitor for mild steel in 1 N H₂SO₄ acid solution by weight-loss and gasometric methods. Studies have also been made in 1 N HCl solution to compare the efficiency of the inhibitor in both acids. Activation energy in the presence and in the absence of the inhibitor has also been evaluated. Galvanostatic polarization data indicate that the compound is predominantly a cathodic inhibitor.