Abstract
Three novel di-quaternary ammonium salts were synthesized, characterized, and tested as corrosion inhibitors for API X65 steel pipeline in 1 M HCl. The inhibition effect of the prepared compounds was studied by EIS, Tafel polarization and weight loss measurements. Polarization curves revealed that the prepared compounds act as mixed type inhibitors. It was found that the inhibition efficiency increased with increasing the compound concentration and decreasing the temperature and also is dependent on the molecular structures. Adsorption of the prepared compounds on API X65 steel pipeline surface is a physical adsorption and obeys the Langmuir's isotherm. (C) 2013 Elsevier Ltd. All rights reserved.