Corrosion Inhibition of Zn in a 0.5 M HCl Solution by Ailanthus Altissima Extract

Abstract

The inhibiting effect of Ailanthus altissima aqueous extract, as a corrosion inhibitor for Zn in a 0.5 M HCl solution, has been evaluated by weight loss (WL), hydrogen evolution (HE), potentiodynamic polarization (PP), electrochemical impedance spectroscopy (EIS) and electrochemical frequency modulation (EFM) techniques. Obtained results showed that this extract offered good protection against Zn corrosion, and exhibited high inhibition efficiencies. The IE was found to increase with an increasing extract dose. Results revealed that this extract acted as a mixed-type inhibitor, and adsorbed onto the Zn surface following Temkin isotherm. Obtained results were justified from the study of surface morphology.Keywords: ailanthus altissima extract; HCl; Zn, corrosion inhibition, WL, HE, PP, EIS, EFM and surface morphology. IntroductionA corrosion inhibitor is a chemical that interacts well with a metal surface, by an adsorption process, to form a thin film/layer that protects the metal surface reducing the movement/diffusion of ions to the latter, or increasing its electrical resistance [1][2]. Zn is one of the most important non-ferrous metals, which finds extensive use in metallic coating. Zn corrodes in a solution with a pH lower than 6 and higher than 12.5, but, within this range, the corrosion is very slow [3]. Under aggressive conditions, Zn metal undergoes corrosion, gaining white colored rust [4,5]. Normally, white rust is observed in galvanized materials, and its occurrence remains a serious commercial problem. In controlling or slowing down the formation of white rust, the search for new inhibitors is essential [6]. A significant method to protect the metals from corrosion is the addition of species

Green inhibitor of carbon steel corrosion in 1 M hydrochloric acid:Eruca sativaseed extract (experimental and theoretical studies)

“…Because of its advantages, such as quick testing, direct corrosion current values without the need for past knowledge of Tafel constants, and the fact that it is non-destructive, EFM is used in this study. 125 This method, like EIS, uses a tiny AC signal, but it differs in a few aspects, such as the fact that it can simultaneously apply two sine waves at different frequencies to the cell. Because the current is a non-linear function of potential excitation, the current response in this approach includes frequency components and input frequencies, which are the sum, multiples, and variance of the two input frequencies.…”

Experimental, Statistical Modelling and Molecular Dynamics Simulation Concept of Sapium ellipticum Leaf Extract as Corrosion Inhibitor for Carbon Steel in Acid Environment

“…Considering the difference in E corr between the unprotected and the protected medium SE is regarded as a mixed-type inhibitor. [30][31][32][33] In conclusion, the trend of inhibition in Table 5 is due to intermolecular relationship between the protonated SE molecules and valence electrons on the Fe surface.…”

Artichoke Extract as an Eco-Friendly Corrosion Inhibitor for Zinc in 1 M Hydrochloric Acid Solution

“…Thence for scale elimination and cleaning of zinc surfaces by acidic solutions, it is required to use inhibitors [3]. The employment of the plant extracts as inhibitors to lower the dissolution of metals in several typical industrial solutions was performed by several authors [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18]. Inhibitors from plant extracts are characterized by its renewable resources, facilely obtainable, low cost and don't form any harmful effects on the environment [19].…”