Green Chemistry Letters and Reviews (Oct 2021)
Paprika extract: a green inhibitor for mitigating carbon steel disintegration in 1 M HCl pickling solution
Abstract
In 1 M HCl pickling media, the paprika extract was used as an ecofriendly anti-corrosive material for carbon steel. Many strategies were utilized to estimate the mitigation efficacy such as potentiodynamic polarization (PP), frequency modulation (EFM), electrochemical impedance spectroscopy (EIS), and mass loss. Surface analyses were accomplished by scanning microscopy (SEM) and dispersion X-ray (EDX) techniques. The mitigation efficacy ameliorates with the concentration of extract and temperature. The inhibition is ascribed to the building of a protective coating at the surface of carbon steel that reduces its dissolution. The adsorption of Paprika extract on steel metal satisfied Langmuir, s model. The adsorption belongs to the physical and chemical types. The adsorption of the extract affected both anodic and cathodic reactions. Tafel curves demonstrated that the Paprika is a mixed inhibitor. The Nyquist curves confirmed that Paprika extract prohibits the disintegration of steel in acid media without changing the dissolution reaction mechanism. The adsorption of the Paprika extract on the carbon steel metal was confirmed by ATR - FTIR analysis and SEM examination. Using 300 ppm of Paprika extract, a maximum inhibitory efficacy of 95% was observed at 313 K.
Keywords