Study on the inhibition of Mild Steel Corrosion by Cationic Surfactant in HCl Medium

Abstract

The inhibition effect of N,N,N-trimethyldodecylammonium bromide(TDAB) as a cationic surfactant on the corrosion of mild steel in 1M HCl has been studied at different temperatures by weight loss, Tafel polarization and Electrochemical impedance spectroscopy. Morphology of the mild steel specimens were examined using scanning electron microscopy and AFM in presence and absence of inhibitor. The results show that TDAB is a good inhibitor, and the inhibition efficiency (IE) increases with the inhibitor concentration as well as increasing the temperature. The adsorption of inhibitor on the mild steel surface obeys the Langmuir adsorption isotherm equation. Polarization curves show that TDAB is a mixed-type inhibitor in hydrochloric acid. Activation parameters and thermodynamic parameters were also discussed. The results obtained from weight loss, polarizations and EIS are in good agreement.