A novel amido-amine based cationic surfactant, namely, 3-decanoylamino-propyl-ethyl-dimethyl-ammonium iodide
(DAEI) was synthesized and its chemical structure was confirmed using FTIR spectroscopy and 1H NMR spectra. The
surface activities of synthesized compound were investigated. Free energies of adsorption and micellization processes
were calculated. The inhibition effect of synthesized surfactant on the corrosion of aluminum in 0.5 M HCl solution was
investigated using weight loss, hydrogen evolution and potentiodynamic polarization techniques. It was found that this
inhibitor acts as a mixed-type inhibitor as well as the inhibition efficiency increases with increasing the inhibitor
concentration, but decreases with raising temperature. Langmuir adsorption isotherm fits well with the experimental data.
Thermodynamic functions for the adsorption process in 0.5 M HCl were determined and explained.