Empirical and quantum chemical studies on the corrosion inhibition performance of some novel synthesized cationic gemini surfactants on carbon steel pipelines in acid pickling processes

Three novel cationic gemini surfactants were synthesized and their effect on the corrosion of carbon steel in 15% HCl solution was investigated using weight loss, electrochemical impedance spectroscopy, potentiodynamic polarization, surface analysis (SEM and EDX) and quantum chemical methods. The surface parameters of the synthesized surfactants were calculated from the surface tension and conductivity measurements The results revealed that the prepared surfactants were effectively inhibited the carbon steel corrosion in 15% HCl. Analysis of polarization data indicates that all surfactants act as mixed type inhibitors. The inhibitors adsorption on the metal surface obeyed Langmuir isotherm. The correlation between empirical and theoretical results was discussed. (C) 2016 Elsevier Ltd. All rights reserved.