The Corrosion Inhibition of Carbon Steel Using Corn Oil-Derived Surfactants

Promoted by the growing interest in eco-friendly products to substitute fossil-derived materials, this research aims to convert renewable feedstocks into chemicals with lower toxicity and production costs. In this study, we investigated the synthesis pathways to convert corn oil into bio-based surfactants and their application in corrosion inhibition. We studied various reaction sequences and extraction systems to synthesize the bio-surfactant. Fourier transform-infrared spectroscopy (FT-IR) and nuclear magnetic resonance analysis (NMR) were used to characterize the bio-surfactant structures. The surface activity of the bio-surfactant was tested using drop shape analysis. The corrosion inhibition properties of the synthesized bio-surfactant in brine were investigated on C1018 carbon steel using weight-loss analysis and electrochemical impedance spectroscopy (EIS). The results of the spectroscopy analysis confirmed the amphipathic structure of the bio-surfactant. The surface tension test showed a decrease in distilled water surface tension by 35% compared to 47.5% using commercial surfactant at a concentration of 2000 ppm. Weight-loss and electrochemical measurements confirmed that the corrosion rate decreased with increasing concentration of the bio-surfactant.