SARACAINDICA (ASOKA) LEAVES EXTRACT AS CORROSION INHIBITOR FOR MILD STEEL IN POTABLE WATER- A BIOREMEDIATION METHOD

摘要

The inhibitive effect of the Saraca indica (Asoka) leaf extract on the corrosion of mild steel in potable water was investigated by using weight loss, open circuit potential measurements and potentiostatic polarization techniques. The threshold concentration of the inhibitor was found to be 500 ppm. At stagnant condition, this concentration of inhibitor shows an inhibition efficiency of 92.4%. The inhibitor was suitable for protecting the mild steel under stimulated conditions also. The corrosion rate was measured at different intervals of immersion of mild steel sample in electrolyte to understand the mechanism of inhibition. The organic part of the leaf extract adsorbed on the surface of the metal and makes a complex on the surface of the metal. This layer will adhere firmly on the metal surface and not depleted with time, temperature and turbulence conditions.