Corrosion inhibition of pure copper using Pisonia Grandis leaves extract in acid Environment

The inhibition effect of Pisonia grandis leaves extract on corrosion of copper in 1.0 N hydrochloric acid was investigated by mass loss measurements with various exposure time and temperature. The present investigation revealed that the percentage of inhibition efficiency is increased with increase of inhibitor concentration and decreased with rise in period of contact. In temperature studies, the observed results reflect that the percentage of inhibition efficiency is decreased with increase of temperature and it suggests that the mechanism follows physical adsorption. The thermodynamic parameters (viz; Ea, ΔH, ΔGads, ΔS) were evaluated for corrosion inhibition process which suggests that the adsorption is exothermic, spontaneous and physisorption. This inhibitor follows Langmuir adsorption isotherm. The protective layer formed on metal surface was analyzed by using spectroscopic studies viz; UV, FT-IR, XRD, SEM and EDX techniques.