Abstract: Laboratory investigations (polarization and electrochemical impedance spectroscopy) were performed in order to assess the effectiveness and the inhibition mechanism of new synthesized imidazoline derivative inhibitor to prevent corrosion of steel in saltwater saturated with carbon dioxide. The inhibitor efficiencies and thermodynamic parameters were calculated. The inhibition efficiency increased with the increase in inhibitor concentration, but increased then decreased with temperature. It was seen that the adsorption of imidazoline derivative on steel fitted the Langmuir isothermequation. The electrochemical results have also been supplemented by quantumchemical analysis.

Key words: EIS, Potentiodynamic polarization, Corrosion inhibitor, Langmuir isotherm, Quantum chemistry