N. O. Eddy *
Department of Chemistry Ahmadu Bello University Zaria, Kaduna State, Nigeria
Received 23 February 2009; accepted 23 October 2009
Abstract
Inhibitive and adsorption properties of ethanol extract of Phyllanthus amarus for the corrosion of mild steel in H2SO4 were investigated using gravimetric, thermometric and gasometric methods. Ethanol extract of Phyllanthus amarus leaves is a good adsorption inhibitor for the corrosion of mild steel in H2SO4. Thermodynamic consideration indicates that the adsorption of the extract is exothermic and spontaneous. Also, the adsorption characteristic of the inhibitor is consistent with the assumptions of Langmuir adsorption isotherm. From the results and findings of the study, a physical adsorption mechanism is proposed for the adsorption of ethanol extract of Phyllanthus amarus on mild steel surface. The inhibition potentials of ethanol extract of Phyllanthus amarus leaves are enhanced by its phytochemical constituents.
Keywords: corrosion, inhibition, Phyllanthus amarus.
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*Corresponding author. E-mail address: nabukeddy@yahoo.com ]]>