Effect of copper content of AISI 1018 mild carbon steel on inhibition efficiency of imidazoline-based corrosion inhibitor in CO2-saturated brine

The effects of the copper content (varied from 0.054 to 0.158 wt%) of AISI 1018 mild carbon steel and precorrosion treatments on the inhibition efficiency (& eta;) of an imidazoline-based corrosion inhibitor was investigated in CO2-saturated brine under dynamic flow conditions at 70 degrees C. An increase in the initial copper content of the steel results in a decrease in & eta; and a decrease in the rate of inhibitor adsorption due to the formation of a porous cementite film enriched with iron carbide and zero-valent copper, leading to an increase in galvanic corrosion.