Synergistic effect of potassium iodide in controlling the corrosion of steel in acid medium by Mentha pulegium extract

摘要

The effect of the mixture of various concentrations of KI and Mentha pulegium extract on the corrosion of steel in 1M HCl has been investigated using weight loss methods. The study revealed that steel is more efficiently inhibited by M. pulegium in the presence of KI than a pure extract of M. pulegium. The inhibition efficiencies increased with an increased concentration of the additives. The highest inhibition efficiency of 84.34 % was observed with single M. pulegium extract at 33 %. An improved inhibition efficiency of 90.59 % was observed with the mixture of 33 % M. pulegium extract and 3 mM KI at 298 K in 1M HCl. Inhibition efficiency increased with temperature from 308-338 K. The adsorption of inhibitor molecules on the metal surface followed Temkin isotherm.