Corrosion inhibition of carbon steel in hydrochloric acid: Elucidating the performance of an imidazoline-based surfactant

A combination of electrochemical measurement and interface analysis have been applied to characterise the interaction OMID, an exemplar imidazoline-based corrosion inhibitor, with carbon steel in 1 M hydrochloric acid. Corrosion inhibition efficiency data indicate that excellent performance is achieved well below critical micelle concentration. High resolution X-ray photoelectron spectra demonstrate that, as rate decreases, evolves towards one comprising OMID bound film-free steel. This latter result provides key input for those researchers attempting predict inhibitor functionality through atomic scale interfacial modelling, so identify next generation chemistries.