Inhibition of Carbon Steel Corrosion in Perchloric Acid Solution by Povidone Iodine

In this study, the influence of Povidone iodine (PVP-I) on the corrosion behavior of carbon steel in perchloric acid solution has been investigated using weight loss method and scanning electron microscopy (SEM). The effect of temperature, immersion time, and concentration of inhibitor on the corrosion of carbon steel were also studied. The effect of temperature on corrosion behavior in the presence of inhibitor was studied in the temperature range of 20–60 °C. The inhibition efficiency increases with increased inhibitor concentration and reaches its maximum of 97.09%. Scanning electron microscopy (SEM) was used to investigate the morphology of the carbon before and after immersion in 1.0 M HClO4 solution containing 130mg L-1 of Povidone iodine. Surface analysis revealed improvement of corrosion resistance in presence of PVP-I. The kinetic and thermodynamic parameters (Ea, K, ΔGads, ΔHads and ΔSads) were evaluated. Adsorption of PVP-I on the carbon steel surface follows the Langmuir isotherm model.