Effect of L-methionine on the passivation, corrosion and inhibition behavior of tin in alkaline medium

The inhibition effect of L-methionine (L-Met) on the corrosion of tin in carbonate medium in presence of chloride ions has been studied by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization technics. Temperature effect on the corrosion behavior with the addition of L-Met studied in the range of temperature from 298 to 328 K. The inhibition efficiency decreases slightly with the increase in the temperature. Results show that L-Met is a good inhibitor and inhibition efficiency reach 82% at 10−3M. The adsorption of this compound on aluminum surface obeys Langmuir’s adsorption isotherm. The kinetic and thermodynamic parameters were determined and discussed. SEM analysis revealed that the addition of inhibitor retards the corrosion processes, where the grain boundary attacks were completely hindered by the adsorbed inhibitor molecules
Applied Journal of Environmental Engineering Science, Vol 4, No 3 (2018)