Corrosion inhibition performance of multi-phytoconstituents from Eucalyptus bark extract on mild steel corrosion in 5% HCl solution

• Published in: International journal of environmental science and technology (Tehran) 2023-03, Vol.20 (3), p.2441-2454
• Main Authors: Aslam, J., Mobin, M., Huda, Aslam, A., Aslam, R.
• Format: Article
• Language: English
• Subjects: Aquatic Pollution; Earth and Environmental Science; Ecotoxicology; Environment; Environmental Chemistry; Environmental Science and Engineering; Original Paper; Soil Science & Conservation; Waste Water Technology; Water Management; Water Pollution Control
• ISSN: 1735-1472; 1735-2630
• DOI: 10.1007/s13762-022-04152-5

The phytochemical constitute of ethanol bark extract of Eucalyptus and its application in inhibiting corrosion of mild steel in 5% HCl solution were investigated. The phytochemical evaluation of eucalyptus crude extract showed the presence of alkaloids, flavonoids, saponins, terpenoids, anthraquinones and steroids, tannins, and glycosides. The corrosion inhibition of mild steel (MS) in 5% HCl solution by Eucalyptus extract was carried out using weight loss, electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization (PDP) measurements at 30, 40, 50, and 60 °C. The results suggest that Eucalyptus extract shows the maximum 98.2% inhibition efficiency at 900 ppm extract concentration in 5% HCl. Also, the adsorption isotherm analysis indicated that the adsorption was the spontaneous and mixed type that followed the Langmuir adsorption law. The surface morphology study via SEM micrograph affirmed the adsorption of Eucalyptus bark (EB) extract constituents on the surface of the mild steel.