Corrosion Inhibition Efficiency Using Mg / Al Hydrotalcite Impregnated with 2-Mercaptoimidazole on API 5L X70 in HCl 1M

This work provides an affordable strategy to enhance the corrosion resistance of hydrotalcite with 2-mercaptoimidazole. The corrosion protection of the API 5L X70 steel immersed in HCl 1M is described by mixture of Mg/Al hydrotalcites impregnated with the organic corrosion inhibitor 2-mercaptoimidazole (HT-2-MI). The effect of this mixture concentration on the efficiency of corrosion inhibition was determined using the techniques of electrochemical impedance spectroscopy and polarization curves. A maximum efficiency of 91% was reached with HT-2MI (20 ppm). Thermodynamic analysis showed that the hydrotalcite+ 2-MI studied followed a physical-chemisorption process in the metal surface.