Three novel bolaamphiphiles as corrosion inhibitors for carbon steel in hydrochloric acid: experimental and computational study

摘要

Three novel bolaamphiphiles were synthesized and investigated as corrosion inhibitors for carbon steel in 1M HCl using weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) measurements. The results reveal that the synthesized surfactants have a good inhibiting effect on the carbon steel in 1 M HCl solution. The results suggest that these inhibitors act as mixed-type inhibitors for acid corrosion of carbon steel. The adsorption of bolaamphiphiles on the carbon steel surface in 1M HCl was found to obey Langmuir isotherm. Polarization results show that, these inhibitors act as a mixed type inhibitors. The inhibitive effect of the investigated surfactants against the corrosion of carbon steel surface was studied by means of AM1 calculations. It was found that the inhibitor with 3-OH groups has the highest inhibition efficiency among the investigated inhibitors. Also, the study of adsorption of the inhibitors on the metal surface shows that the adsorption occurs through the charge biphenyl moiety and the lone pair of oxygen atoms of hydroxyl groups. The calculations showed that the surfactants with 3-OH has the highest inhibition efficiency which agrees well with the experimental data.