Abstract

Inhibitive action of stearamidopropyl dimethylamine (SAPDA) which considered as cationic surfactant against the corrosion of carbon steel in a 0.5 M HCl solutions was investigated using electrochemical impedance spectroscopy (EIS), linear polarization resistance (LPR) and potentiodynamic polarization techniques. This investigated compound was found to act as effective corrosion inhibitor for the tested system. The polarization data indicated that this surfactant acts as mixed type inhibitor. The inhibition efficiency increased with increasing cationic surfactant concentration and decreased with raising the temperature. The adsorption of the cationic surfactant on the carbon steel surface followed the Langmuir adsorption isotherm model.

Keywords

Carbon steel, Acid corrosion, Cationic surfactant, EIS, LPR