Corrosion Inhibition of Mild Steel in Seawater by 2,4,6-Triamino-3-Pentadecylphenyl Acetate Derived from Cashew Nut Shell Liquid
The corrosion inhibition performance of 2,4,6-triamino-3-pentadecylphenyl acetate on mild steel in seawater at stationary condition, 30 °C and pH 8 was investigated using potentiodynamic polarization and electrochemical impedance spectroscopy. The maximum inhibition efficiency of 93% was found in the presence of 300 ppm of 2,4,6-triamino-3-pentadecylphenyl acetate for both potentiodynamic polarization and electrochemical impedance spectroscopy techniques. The potentiodynamic polarization curves show that 2,4,6-triamino-3-pentadecylphenyl acetate acts as a mixed type inhibitor which influences more the anodic processes. The Nyquist plots revealed that the polarization resistance (Rp) increases whereas the double-layer capacitance (Cdl) and corrosion current density (icorr) decrease as the concentrations of the inhibitors increase due to the formation of a protective layer of inhibitor over the mild steel surface. The results obtained from the two electrochemical techniques are in good agreement. The adsorption of 2,4,6-triamino-3-pentadecylphenyl acetate on the mild steel surface obeyed Langmuir adsorption isotherm.
Keywords: Cashew nut shell liquid; 2,4,6-triamino-3-pentadecylphenyl acetate; corrosion inhibitor; mild steel; seawater.
Copyright for articles published in this journal is retained by the journal.
This journal provides immediate open access to its content on the principle that making research freely available to the public supports a greater global exchange of knowledge