An Investigation on the Performance of an Imidazoline Based Commercial Corrosion Inhibitor on CO2 Corrosion of Mild Steel

The performance of an Imidazoline based commercial corrosion inhibitor on CO2 corrosion of mild steel was investigated in a Cl- containing solution employing linear polarization resistance (LPR), potentiodynamic polarization and monitoring corrosion potential techniques. Experimental results showed that an increase of the commercial inhibitor concentration up to 500 ppm increases the RP value and produces an efficiency of 90 percent. The increase of a test solution temperature at 60°C caused an increase on RP value compared to RP measured at room temperature this suggests adsorption of the inhibitor is promoted by temperature. Plot of c/θ versus inhibitor concentration (c) using different methods showed a straight line with a slope very close to unity, indicating that adsorption of the investigated commercial inhibitor on steel/saturated CO2 solution obeys the Lungmuir adsorption isotherm.