Anticorrosive assay-guided isolation of active phytoconstituents from Anthemis pseudocotula extracts and a detailed study of their effects on the corrosion of mild steel in acidic media.

Journal Article

Publication Abstract

In this study, anticorrosive properties of various extracts (methanolic, aqueous methanolic and water
extracts) of Anthemis pseudocotula for mild steel in 1.0 M HCl media is screened for the first time. Among
the various tested extracts, the methanolic extract of A. pseudocotula shows the highest corrosion
inhibition activity. Anticorrosive assay-guided isolation of this methanolic extract results in the isolation of
a highly potent anticorrosive compound, APB (luteolin-7-O-b-D-glucoside). The anticorrosive effects of
APB on mild steel in 1.0 M HCl media were evaluated in detail using gravimetric, Tafel plots, linear
polarization, electrochemical impedance spectroscopy and SEM and EDS techniques. Tafel plots reveal
that APB acts as a mixed-type inhibitor. The adsorption behaviour of this green inhibitor on the mild-steel
surface obeys the Langmuir adsorption isotherm. A surface morphology study through SEM and EDS
analysis displays a noteworthy upgraded surface morphology of the mild steel plate in the presence of the
green inhibitor in 1.0 M HCl media. The results obtained from electrochemical tests and weight loss
measurements are in good agreement which shows excellent inhibition efficiency for the natural
compound APB.