Inhibitive action of alkaloids and non alkaloid fractions of the ethanolicextracts of Phyllanthus amarus on the corrosion of mild steel in HCl solution
The corrosion inhibition of mild steel in 2.0 MHCl solution by non-alkaloidal and alkaloidal fractions of the extracts of Phyllanthus amarus (NAEPA and AEPA respectively) was studied using gravimetric and gasometric techniques at 303 and 323 K. The results revealed that the extracts functioned as good corrosion inhibitors. Inhibition efficiency was found to increase with the concentration of the extracts. The inhibition efficiency was found to increase with temperature for NAEPA and increase with decrease in temperature for AEPA. A mechanism of chemical and Physical adsorption is proposed for NAEPA and AEPA respectively. The adsorption of the inhibitors followed the Langmuir adsorption isotherm.
KEYWORDS: Phyllanthus amarus, mild steel, alkaloid, corrosion inhibition.