A theoretical and experimental study of phosphate ester inhibitors for AISI 1018 in carbon dioxide‐saturated 3.5 wt% NaCl solution

Abstract

Phosphate ester was investigated as a corrosion inhibitor for AISI 1018 carbon steel in carbon dioxide‐saturated chloride solutions at different temperatures and pressures. The corrosion tests were realized by electrochemical techniques, weight loss measurements, bubble tests, and a high‐pressure/high‐temperature autoclave system. The corrosion tests demonstrated that the investigated molecule is an excellent corrosion inhibitor. The inhibiting effect is even bigger at high pressure and temperature than at atmospheric pressure and room temperature. The thermodynamic parameters were calculated and determined to obey the Langmuir isotherm. Polarization studies revealed that the evaluated inhibitor is a mixed type.

Study of the Efficiency of the Amino Acid L-Histidine as a Corrosion Inhibitor of 1018 Carbon Steel in Saline Solution Without and with CO2 Saturation

“…The reference electrode was made of Hastelloy alloy, while the counter electrode was manufactured using a platinum plate with an area of 2.45 cm 2 . The conventional reference electrode (Ag/AgCl or saturated calomel) typically employed in electrochemical assays proves unsuitable for this system, as the inhibitor infiltrates the porous tip, contaminating the internal solution 21 .…”