Corrosion inhibition properties of iodide ionic liquids for API 5L X52 steel in acid medium

A mechanism for describing the corrosion inhibition of API 5L X52 steel in 1 M H2SO4 employing two ionic liquids (ILs) with imidazolium-derived cations and iodide anion as corrosion inhibitors (CIs) at stationary and dynamic states is proposed. The adsorption process occurred firstly through the adsorption of iodide ions (I-) on the metal surface as a result of the coulombic force, which promoted the subsequent adsorption of the imida-zolium cation. The maximal inhibition efficiency (IE) values for the ILs ranged from 91 to 95 %. Likewise, the XPS, computed tomography, SEM and AFM results supported the obtained IEs.