Corrosion inhibition potentiality of some benzimidazole derivatives for mild steel in hydrochloric acid: Electrochemical and weight loss studies

The adsorption and inhibition effects of three benzimidazole derivatives (BDD), namely: 2-(2-pyridyl) benzimidazole (PBD), 2-bromo-1H-benzimidazole (BrBD), and 2-chloro-benzimidazole (ClBD) on mild steel corrosion in 1 M HCl have been studied by electro-chemical and weight loss methods. Results showed that inhibition efficiency increases with concentration and maximum value was obtained at 5.10(-3) M concentration. From the results, it is concluded that the BDD inhibited mild steel corrosion in 1 M HCl by adsorbing on the metal surface. Polarization results showed that the BDD act as mixed type inhibitors. The adsorption of BDD onto the mild steel surface was described by the Langmuir adsorption isotherm.