Extracting Ellagic Acid from the Pomegranate Fruit Peels and its Application as an Inhibitor of Carbon Steel ۴۵ Corrosion in Different Media

This study suggests a solution to the corrosion issue faced by carbon steel by reducing corrosion and improving protection using a natural inhibitor, ellagic acid. The inhibitor ellagic acid is extracted from pomegranate fruit peels. It was characterized using Fourier Transform Infrared Spectroscopy (FTIR). Using the electrochemical polarization technique, the corrosion behavior of carbon steel ۴۵ in ۱M of hydrochloric acid (HCl) and a saline medium (artificial seawater ۳.۵% NaCl) was investigated before and after using the different concentrations of inhibitor ellagic acid (۰.۰۱ and ۰.۰۵) M at four temperatures: ۲۹۸, ۳۰۳, ۳۱۳, and ۳۲۳ K. The thermodynamic parameter of the corrosion behavior of carbon steel in two media under study, which include: energy activation Ea (۱۵.۱۰۱-۶.۷۳۸ kJ/mole) enthalpy ∆H*(۱۳.۲۱۰۵-۴.۸۴۷ kJ/mole), entropy ∆S*(-۰.۱۴۴۴- (-۰.۱۹۳۲) J/mole), and free Gibbs energy ∆G*(۰.۰۵۵ -۰.۰۶۱kJ/mole) for ۱M HCl and energy activation Ea (۴.۲۱۶۴۹-۲۲.۲۵۳۶ kJ/mol), enthalpy ∆H* (۲.۳۲۵۲۹-۲۰.۳۶۲۴ kJ/mol), entropy ∆S*(-۰.۱۸۶۱- (-۰.۱۵۴۶۵) J/mol), and free Gibbs energy ∆G*(۰.۰۵۶۸-۰.۰۶۵۶kJ/mole) for ۳.۵% NaCl before and after using the inhibitor, were also studied. The result showed that the inhibition efficiency values in the sodium chloride solution containing the inhibitor ranged from ۹۳-۹۷% at a concentration of ۰.۰۱ M and ranged from ۹۷-۹۹ % at a concentration of ۰.۰۵ M, and the inhibition efficiency values in the hydrochloric acid solution containing the inhibitor ranged from ۹۱-۹۴% at a concentration of ۰.۰۱ M and ranged from (۹۵-۹۶)% at a concentration of ۰.۰۵ M. Atomic Force Microscopy (AFM) analysis of the electrodeposited layers shows a protective coating layer of ellagic acid on carbon steel (C۴۵).

کلیدواژه ها:

ellagic acid ، pomegranate fruit peels ، natural inhibitor ، Corrosion Inhibition ، carbon steel (C ۴۵)