THE USE OF ECO-FRIENDLY WILD ONION EXTRACT (URGINEA MARITIMA) AS CORROSION INHIBITOR FOR CARBON STEEL IN HYDROCHLORIC ACID

Abstract

Even though various synthetic compounds have a well action as anticorrosive, they are not cheap and are toxic to both environment and humans. Nevertheless, in C-steel, there is a vital concern, which is serious corrosion issues happen through exposure to environments of aggressive acidity i.e., descaling, oil well solutions of acidity, and pickling. Hence, this study aimed to evaluate the inhibition effect of wild onion (WO) extract as an eco-friendly inhibitor on the behavior of corrosion for C-steel in 0.5 M HCl through the conventional weight loss approach. Various concentrations (0%, 0.5%, 1%, 1.5%, 2%, and 2.5%) of inhibitor in various times of immersion (2, 4, and 8 h) and at different temperatures (25°C, 35°C and 45°C) were investigated for their C-steel corrosion inhibition in corrosive media. In the presence and absence of the inhibitor, the corrosion rate (CR) was investigated as affected by temperature. The concentration of the inhibitor and temperature-controlled the inhibition efficiency %E of the inhibitor. At the existence of wild onion extract, the ideal efficiency of inhibition for C-steel was 98.95%, 88.99%, and 86.79% at 2.5% inhibitor concentrations at the preceding temperatures, respectively. It was noticed that adsorption was spontaneous and physical as proved through adsorption value of free energy ΔG°ads (‒13.5 kJ/mol) and also fitted Langmuir adsorption isotherm. The surface coverage θ and corrosion current density Icorr data confirmed the previous result where inhibition is due to the adsorption of physical nature for the components of the additive on the C-steel surface.