Studies on the Inhibition Characteristics of Eriochrome Black-T during the Corrosion of Zinc in Acid Media

The corrosion of zinc in acidic medium in the presence of Eriochrome Black-T (EBT) as inhibitor has been studied at four temperatures (303, 313,323 and 333 K) by weight-loss method. The percent inhibiton efficiency, the rate of corrosion (mils per year) and the surface coverage have been evaluated. The heat of adsorption and the activation energy have also been calculated for the corrosion inhibition process. Finally, the free energy change for the corrosion inhibition process has been determined. It is observed that, EBT acts as a good inhibitor for the corrosion of zinc at low temperatures. At higher temperature and at lower concentrations (10^-9M) it rather acts in a catalytic manner.