Quantum modeling design of imidazoline-based corrosion inhibitors for oil industry applications

Abstract We applied the Density Functional Theory to investigate the performance of imidazoline-based corrosion inhibitors for protecting iron surfaces under aggressive environment containing O2, H2S or CO2. We found that the performance of these corrosion inhibitors correlates with their adsorption energies over the corroded surfaces, i.e., the better (worst) performance is reached under presence of CO2 (O2) because the adsorption energies are more (less) intense. Likewise, amino substituents attached to the imidazoline ring allow to form chelates with the corroded surfaces, substantially enhancing the inhibition performance. Additionally, benzene-based substituents help to the inhibition properties.