Inhibition of corrosion of mild steel in well water by an aqueous extract of soapnut (Sapindus Trifoliatus)

Inhibition efficiency of an aqueous extract soapnut (Sapindus Trifoliatus) and Zn2+in controlling corrosion mild steel in well water at room temperature has been evaluated by using weight loss method, polarization study AC impedance spectra. Dynamic light scattering Vickers hardness have also employed. Weight method reveals that the formulation consisting 10 ml 50 ppm Zn2+ 97 % inhibition immersed water. Synergism parameters suggest a synergistic effect exists between Zn2+. Adsorption isotherm metal surface obeys Langmuir adsorption isotherm. Polarization inhibitor system functions as anodic type inhibitor. spectra confirm protective film formed on surface. (DLS) is nano meter scale. The was increases system.