Study of inhibition and adsorption properties of mild steel corrosion by expired pharmaceutical Gentamicin drug in hydrochloric acid media

Abstract

This experiment avoids pollution and recycles of the drugs and also promotes economically benefited inhibitor. In this experiment expired Gentamicin drug was under studied for testing its inhibitive effect on mild steel in 1 M HCl acid medium with the weight loss and electrochemical techniques. The Various parameters were calculated such as corrosion rate, inhibition efficiency and surface coverage. The weight loss method shows that the inhibition efficiency increases when inhibitor concentration, immersion period and temperature increases.Obtained results in electrochemical Impedance and weight loss studies are very much excellent agreement with each other. Thermodynamic parameter like free energy value was negative, that shows spontaneous adsorption of inhibitor on the surface of the mild steel. The adsorption nature of the inhibitor on the surface of mild steel was under conformity with Langmuir adsorption isotherm. The mild steel surface morphology, with and without inhibitor was studied by using scanning electron microscopy.