Original Articles
A. Sirajunnisa, M. I. Fazal Mo
Abstract
The present work investigates corrosion inhibition of aluminium in 1N NaOH solution in presence of Vitex negundo (VNL) leaves extract as green corrosion inhibitor by using chemical and electrochemical techniques. It was found that the inhibition efficiency increased with increase of VNL extract and reached the maximum of 72.6% at 900 ppm of VNL extract. The results obtained from chemical and electrochemical measurements were in good agreement. The potentiodynamic polarization studies reveal that the VNL extract act as mixed type inhibitor. Adsorption of VNL extract on the surface of aluminium follows Langmuir adsorption isotherm. The surface characteristics of inhibited and uninhibited aluminium were investigated by scanning electron microscope studies. These results were supported by kinetic and thermodynamic parameters obtained from weight loss data at different temperatures studied.