Corrosion Inhibition of Aluminum by Psidium Guajava Seeds in HCl Solution

Abstract

The corrosion inhibition and adsorption of ethanol extracts of Psidium guajava seeds (EEPgS), for aluminum in 0.5 N HCl solutions, were investigated using conventional weight loss, FTIR spectroscopy and SEM analysis techniques. The results showed that EEPgS performed well as inhibitor for the corrosion of aluminum in hydrochloric acid media. FTIR results showed that the inhibition mechanism was by adsorption process, through the functional groups present in the extract. Inhibition efficiency increased with increasing concentration of the plant extract, but decreased with the temperature rise. The weight loss data were fitted into a number of isotherms, though Langmuir model was found to be the best fit. The SEM photographs confirmed the protection offered by the extract on the surface of the metal.Keywords: Psidium guajava; aluminum; corrosion; inhibitor; adsorption. IntroductionIndustrial processes such as prickling and acid cleaning often involve contact between a metal and aggressive solution, consequently, the metal is prone to corrosion. In order to reduce the menace due to corrosion of industrial installations, several steps have been adopted. However, one of the best options available for protecting metals against corrosion involves the use of corrosion inhibitors [1][2]. The majority of well-known inhibitors are organic compounds containing hetero atoms, such as O, N, S, and multiple bonds, which allow an adsorption on the metal surface [3]. These compounds adsorb on metal surface and block the active surface sites to reduce the corrosion rate. Adsorption may take place by four different mechanisms through organic molecules at the metal/solution interface: (a) electrostatic attraction between the charged molecules and the charged metal, (b) interaction of uncharged electron pairs in

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Chrysanthemum Flower Extract as a Green Inhibitor for Aluminium Corrosion in Alkaline Medium

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Performance of Anticorrosive Measures of Steel in Concrete Infrastructure by Plant‐Based Extracts

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