Evaluation of the anticorrosion performance of peel garlic extract as corrosion inhibitor for ASTM 1020 carbon steel in acidic solution

Resumo

Metallic corrosion can be delayed using corrosion inhibitors. However, several industrial corrosion inhibitors
are toxic and harmful to the environment and to the human health. In this context, in the last decades, research
has been developed to investigate the performance of low toxicity corrosion inhibitors as green inhibitors
obtained from vegetables, which are environmentally acceptable. The present work studied the corrosion
inhibition efficiency of peel garlic extract (Allium sativum. L.) for possible replacement of benzotriazole
(BTAH) on the corrosion inhibition of ASTM 1020 carbon steel (CS-1020) in 0.5 mol.L-1 hydrochloric acid
media. Weight loss measurements, anodic and cathodic potentiodynamic curves and electrochemical impedance
(EIS) experiments were carried out. The Fourier transformed infrared spectroscopy (FTIR) was carried
out to evaluate the chemical compounds. The morphological characterization was obtained to observe the
inhibitor effect in the corrosion products on substrate surface. The results showed that the addition of both
inhibitors effectively hinder the corrosion process and indicated their adsorption on the electrode surface. The
inhibiting efficiency of the peel garlic extract was only slightly inferior to BTAH showing that the former
inhibitor can be an environmentally friendly option to toxic inhibitors. The FTIR analysis showed the presence
of chemical compounds which presents antioxidant properties.