Inhibition study of Erioglaucine disodium salt on carbon steel in hydrochloric acid medium using weight loss, electrochemical and thermodynamic properties

Abstract

The corrosion inhibitory action of Erioglaucine disodium salt (EDS) on carbon steel in acid medium was evaluated by weight loss measurement, impedance and polarization studies. The increased inhibitory action against corrosion in the presence of inhibitor with increased of Erioglaucine disodium salt concentration. The effect of concentration and temperature studies were performed on the inhibition effect. The adsorption efficiency of Erioglaucine disodium salt was corroborated with high capacitive loop of Nyquist plot. The polarization behavior of Erioglaucine disodium salt concentration has been recorded showed it behaved as mixed type nature in acid medium. The enhancement in the inhibition action on the carbon steel has increased with increasing inhibitor concentration. The Langmuir adsorption isotherm gave information about the adsorption mode with carbon steel. Thermodynamic properties (ΔS∗, ΔH∗, ΔG° and Ea) of the Erioglaucine of the adsorption reaction were measured from the temperature effect. The hydrogen gas evolution measurement showed the strong adsorption nature of the inhibitor with the metal surface. The surface protection effect of Erioglaucine disodium salt on the carbon steel has studied with SEM and FTIR analysis.