Corrosion Inhibition of Steel in HCl by 2–Aminoethyl diphenylborinate

Abstract

The corrosion behavior of C38 steel in HCl solution with different concentration of 2-Aminoethyl diphenylborinate C14H16BNO(DDB) was investigated by weight loss and electrochemical measurements. Results obtained reveal that DDB performs excellently as corrosion inhibitor for C38 steel in 1.0 M HCl. Potentiodynamic polarization studies have shown that DDB behaves as mixed -type inhibitors. Also, the inhibition efficiency was found to increase with increase of the inhibitor concentrations to reach 97.8 % at 2.10- 3M of DDB due to the adsorption of the inhibitor molecules on the metal surface and the adsorption follows Langmuir's adsorption isotherm. EIS spectra exhibit one capacitive loop and confirm the inhibitive ability. Double layer capacitance and charge transfer resistance values were derived from Nyquist plots obtained from impedance studies. Data obtained from EIS measurements, were analyzed to model the corrosion inhibition process through appropriate equivalent circuit model; a constant phase element (CPE) has been used.