Corrosion Inhibition Character of Azure B for Mild Steel in Hydrochloric Acid Solution

摘要

The corrosion inhibition behavior of azure B (AB) on mild steel in 0.5 M hydrochloric acid mediumwas investigated by gravimetric, potentiodynamic polarization and electrochemical impedancemeasurements. The inhibition efficiency of AB showed an improvement with increasing concentrationup to a critical value of AB, beyond this concentration no further effectiveness is observed. Theadsorption of AB on mild steel surface was found to obey Langmuir adsorption isotherm. Thesynergetic effect was also studied between AB and KI, and the addition of KI enhances the inhibitionefficiency of AB significantly. Quantum chemical parameters were used to correlate the inhibitionefficiency and molecular structure of AB. Further, the surface adsorbed film was analyzed by scanningelectron microscopy.