Evaluation of Phosphate Tridecyl Ethoxylate Triethanolamine Salt as a Corrosion Inhibitor in CO2-O2 Environment for Carbon Steel

Abstract

Investigation of corrosion inhibitors on CO2-saturated aqueous solution with O2 contamination is limited. Hence, this study investigated the corrosion behavior of phosphate ester inhibitor towards carbon steel corrosion in a simulated CO2-O2 environment by potentiodynamic polarization technique and electrochemical impedance spectroscopy. It was shown that the PE prevents the corrosion attack in the presence of CO2-O2, reaching an efficiency of 90.7% with 25 ppm in 3.5 wt% NaCl solution at 25 oC. Furthermore, the superficial characterization of carbon steel was studied by scanning electronic microscopy which supported that the inhibitor protects against corrosion. The varying temperatures showed that PE adsorbed on the steel surface by a physical process and obeyed the Langmuir isotherm.

Keywords

• Inhibitor
• phosphate ester
• CO2 corrosion
• O2 corrosion