The Inhibition Effect of Bis-Benzimidazole Compound For Mild Steel in 0.5 M HCl Solution

摘要

The compound BBMB was synthesized from the dehydration reaction o-phenylenediamine and 1, 4- benzendicarboxylic acid in polyphosphoric acid. The effectiveness of BBMB as corrosion inhibitor formild steel in 0.5 M HCl solution was investigated by various techniques such as weight lossmeasurement, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS). Theresults of these investigations showed enhancement in inhibition efficiencies with the increase inBBMB concentration and even at the concentration 0.01 mM the IE% exceeded 80%. BBMBsuppressed both mild steel dissolution and hydrogen reduction processes acting as a mixed-typeinhibitor. The excellent inhibition effectiveness of BBMB was also verified by scanning electronmicroscope (SEM). BBMB precluded mild steel corrosion by blocking the active sites on mild steelsurface. The adsorption of BBMB on mild steel surface obeyed Langmuir adsorption isotherm.