<i>Glaucium</i> Extract as an Effective Green Corrosion Inhibitor for a Mild Steel in High Concentrated Sulfuric Acid Solution

Abstract In this study, the objective was to evaluate the inhibitive corrosion performance of the Glaucium extract (GL) in sulfuric acid solution (15% vol). This was examined using both gravimetric and electrochemical methods, with a variation in the extract concentration, the immersion time spent, and the temperature. The highest inhibition efficiency, up to the 95%, was shown. at a concentration of 1250 ppm. The inhibitor maintained a comparatively high level of performance under all tested conditions, although a gradual decrease in efficiency that was noted with increasing temperature and longer immersion time. Based on the Langmuir isothermal model, findings indicate that GL functions as a mixed inhibitor for the mild steel. The effects on the surface were shown through different surface characterizations such as scanning electron microscope (SEM) coupled with energy‐dispersive spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR), and X‐ray diffraction (XRD). These techniques affirmed the adsorbed protective film attributed to the GL that effectively covers the surface. This highlights the inhibitor's strong protection, with clear evidence of its adsorption onto the studied material.