Corrosion Inhibition and Adsorption Mechanism of Eugenol on Copper in HCl Medium

Resumo

The corrosion of copper has been received much attention due to its high affected to everyday life and industry. Eugenol is abundant natural product and can be extracted from Cloves. This work eugenol was used as inhibitor for copper corrosion. The effect of eugenol concentration, immersion time and temperature has been studied. The results showed that eugenol can protect corrosion with inhibition efficiencies of 70% (1.2 M HCl environment at 303 K). The HPLC, FT-IR and SEM techniques have been employed to characterize and to study surface morphology. Furthermore, the sorption isotherms have been evaluated and revealed the adsorption mechanism is best described by the Frumkin isotherms with the free energy of –15.68 k J mol^–1 and consistent with the physical adsorption. Quantum chemical calculation has been also used and discussed relating to corrosion inhibition.