Black Wattle Tannin As Steel Corrosion Inhibitor

Figure 2

(a) FTIR spectrum of the black wattle tannin and (b) FTIR spectrum of the blue-black precipitate formed in the bulk of the electrolyte after one hour of immersion of steel in aerated 0.1 mol L⁻¹ Na₂SO₄ solution (pH 6.0) in the presence of acacia tannin.